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I've moved the blog

2010-07-27T07:03:00.003+01:00

I've moved all my photographic blogging to my new blog - www.allkins.co.uk.

I'll be slowly porting over some stuff from here and and adding a whole lot more content.

I'm back

2010-06-18T15:29:00.000+01:00

Well after what seems like an age (it has been over a year...) I'm finally finding time to take more pictures and write the blog.

The plan tomorrow (assuming the English summer perks up a bit) is to take the new Tamron 180mm macro lens to Stowe Gardens.

Will blog about the experience and post some pictures if I do.

Hertford RFC 1st XV vs. Luton

2009-02-07T09:41:00.021Z

Back to rugby again, this time Hertford's 1st XV playing local rivals Luton on 31st January.

The curtain raiser to the afternoon was a match between Hertford Under 9s and Luton Under 9s which was won convincingly by Hertford - 55-0. The juniors then formed a guard of honour for the players running out for the main event.

The senior match really was a game of two halves. Luton had the upper hand in the first half going in 8-14 in the lead and looking like the game was theirs. But Hertford staged a very impressive comeback in the second half - scoring 36 unanswered points.

Well done Hertford - a fantastic result and great rugby :-)

If you are a member of Hertford RFC and would like a copy of any of the pictures please get in touch using the details at the bottom of the page.

Under 9s Pictures

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2009

The main match - Hertford 1st XV vs. Luton

The full match report is on the Hertford RFC message board.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2009

Children of the Kindertransport

2009-02-02T22:41:00.006Z

One of less well known stories from just before WWII is the "Children of the Kindertransport".

Just before the outbreak of war approximately 10,000 Jewish children were evacuated from Germany to Britain after Kristallnacht, with many passing through London Liverpool Street station which I use every day. One of the children who was evacuated was sculptor Frank Meisler who was commissioned in 2006 to create a sculpture to commemorate the children who were admitted by and the generosity of the British.

Below is a photograph of the sculpture taken this morning in the snow (with my little Lumix LX3).

Click on the picture to see a larger version in Lightbox.
© Dominic Allkins, 2008

While 10,000 children did make it into Britain over 1.5 million didn't. A figure so mind boggling huge that it is almost unimaginable and is definitely tragic.

You can find more about the sculpture and Frank Meisler at this page on Frank Meisler's website.

Creating planets

2009-01-29T10:49:00.007Z

Whenever I have the time to get out with the camera it seems to be hosing down with rain :-( Don't you just love the British weather?

So inevitably I end up playing with Photoshop and trying out a few new things. Someone over at Dynax Digital posted a link to Photojojo about how to create 'planets' from panoramas - so I had a play.

The results are pretty cool - see below.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

Hertford RFC 2nd XV vs. Richmond Saxons

2009-01-17T19:25:00.003Z

A good afternoon was spent watching Hertford RFC 2nd XV beat Richmond Saxons convincingly 29-16. It was a good competitive game and a deserved scoreline.

This was the first time I'd tried out the Alpha 900 and 70-200G combination for sports photography since I bought it and I'm pretty pleased with the results below.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2009

Positively Tropical

2009-01-11T19:49:00.008Z

After the cold grey weather over the last couple of weeks today's temperature seemed positively tropical. OK, well maybe not, but it was a lot warmer than it has been.

The best bit of the day though was sunrise. Just stunning.

The images below were taken from my balcony and was the view I had from the kitchen this morning :-)

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

I also created a panorama which I'll detail in another tutorial in a couple of days. I'm getting this printed 5 feet wide and board mounted. It should look stunning.

Here is a larger version. (250K image)

Enjoy

Dominic

ps. There was almost no post-processing with these images. It's pretty much as I saw it. Incredible.

Seals and Pups on Boxing Day

2009-01-10T09:47:00.005Z

I've finally found a bit if time to start sorting our my pictures from the Christmas and New Year break - I took about 500 overall.

On Boxing Day I went for a walk along the sea defences at Waxham Beach on the Norfolk Coast to see and photograph the seals and their pups. Freezing cold but worth it to be able to get so close to such beautiful animals.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

They will be there again next year so if you wrap up warm you'll have a great day.

Fine tuning a landscape – Part Four – Cropping for Composition

2009-01-02T20:56:00.006Z

I had three main reasons for wanting to crop the final image.

Most importantly, I wanted to have the hedge as a lead-line from the bottom left of the final image to the Wrekin, drawing the eye across and up the frame
I wanted to get rid of the metal post in the end of the hedge
Finally, I wanted to remove some of the 'dead ground' at the front of the foreground

After cropping, I was left with the following final image.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

The final image is now printed and just waiting for a frame before hanging on the wall.

I hope that this series of posts has been interesting and that detailing the techniques I've used will come in useful if you ever find you need to do the same thing yourself.

Dominic

ps. The observant among you may have noticed that I used a different image second time around. I preferred the cloud formations in this one on closer inspection.

Fine tuning a landscape – Part Three – Fixing the Dynamic Range

2009-01-02T19:18:00.020Z

As I said in the first post in this series, the first time I posted this image was based on a bit of 'quick and dirty' post processing – about five minutes for one pass through Adobe Camera Raw. The result was acceptable for posting a resized image online, but not good enough quality for 100% viewing on screen or printing. To end up with an image that would give a high quality printed result needed a bit more time and attention.

The basic principle is to double process the RAW file in Adobe Camera Raw – first to make sure the exposure of the sky was correct and then a second processing for the foreground. The results of each of these two phases of processing are saved as TIFF or Photoshop files, loaded into Photoshop and merged with a bit of masking – detailed below.

Processing for the sky

It's worthwhile revisiting the original RAW file to have a look at the task in hand before detailing the process.

Click on the picture to see a larger version in Lightbox.
© Dominic Allkins, 2008

If you recall from the original post I didn't have time (due to two potentially impatient daughters) to work with graduated filters so I originally exposed for the sky as it is almost impossible to recover lost detail from blown-out highlights and much easier to deal with the under-exposed foreground. Even though the sky was nicely exposed with good cloud detail and nice blues, I wanted to achieve an effect with a bit more impact. To do so meant darkening the sky a little.

The Lightroom settings were pretty minimal (only making changes in the Basic tab) as you can see from the screengrab below.

Changes made

Exposure: -0.10
Blacks: 37
Clarity: +10
Vibrance: +20

This gave the following result:

Click on the picture to see a larger version in Lightbox.
© Dominic Allkins, 2008

This has given the sky a real boost, but obviously leaves a very underexposed foreground - but that's what I planned for. So next I fixed that.

Processing for the foreground

To correct the under-exposure of the foreground in the original shot meant I needed to lighten the foreground. I also decided to lift the green shoots of the new crop by boosting the Hue/Saturation and Luminance of the green. Again, changes were minimal. The screengrabs from the Lightroom tabs are:

Changes made

Exposure: +1.50
Fill Light: 13
Clarity: +10
Vibrance: +20
Green Hue: +5
Green Saturation: +10
Green Luminance: +15

Exposing for the foreground in this way gave the following result:

Click on the picture to see a larger version in Lightbox.
© Dominic Allkins, 2008

This time we see a nicely exposed foreground and a blown-out sky.

All that's left to do now is to blend the two images in Photoshop to get the image ready for cropping.

Blending in Photoshop

Blending the two images in Photoshop is a fairly simple process. I opened both the Lightroom processed files and created a layered Photoshop file containing both images - the sky exposed image as the base layer and the foreground exposed layer on top. With the foreground exposure selected I created a layer mask (click in the white circle in the rectangle) and using the paintbrush set to black paint out the area of the foreground exposure I wanted to mask out. For this image I also had to create a second Hue/Saturation layer for the lower branches of the tree on the foreground exposed image as they were still green. The layer panel below is from Photoshop.

This left me with the following image ready for final cropping.

Click on the picture to see a larger version in Lightbox.
© Dominic Allkins, 2008

>> Part Four – Cropping for Composition

Fine tuning a landscape – Part Two – Dealing with the Chromatic Aberrations

2009-01-01T20:08:00.015Z

Chromatic aberrations themselves are relatively easily to reduce or remove altogether in post-processing and I have detailed two different methods of dealing with this problem.

What causes chromatic aberrations?

You are most likely to find chromatic aberrations around areas for high contrast such as, in this case, the backlit tree. This effect is caused by the way lenses deal with the light passing through the lens and hitting the sensor. In fact, if you read most lens tests online you're almost certain to read about how much the lens suffers from chromatic aberrations. In fact, the test is often carried out using a backlit tree like that shown in this picture.

The better the lens, the less likely you are to see chromatic aberrations. This picture was taken with the Sony Carl Zeiss 16-80mm standard zoom lens which despite being a very high quality lens still shows this problem.

How to fix chromatic aberrations

There are a number of ways of dealing with chromatic aberrations, depending which software you use. Since I take all of my photographs in RAW format I tend to use the tools available in Adobe Camera Raw CS4 (ACR) or Adobe Lightroom 2 (the tools are the same for both pieces of software) for fixing this problem first which normally give a very good result. If I'm not entirely happy with the result from ACR I’ll also try fixing the chromatic aberrations with Photoshop CS4 as well. In this picture, the results from Photoshop were better so this was the final approach used for this photograph.

Fixing Chromatic Aberrations using ACR/Lightroom 2

The tools for fixing Chromatic Aberrations in ACR/Lightroom are found in slightly different places; either in the 'Lens Corrections' tab in ACR or the 'Detail' tab in Lightroom, but the tools are the same. The screengrab below (from Lightroom) shows the tools while the following two images show a 100% crop before and after correcting with ACR/Lightroom.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

We can clearly see that the chromatic aberrations are much better after attempting to fix in Lightroom, but there is still a small amount of fringing evident around the branches. Because of this I attempted to fix these in Photoshop CS4 directly.

Fixing Chromatic Aberrations using Photoshop CS4

Fixing Chromatic Aberrations using Photoshop CS4 is a little more involved and takes a little longer but can give better results. It is essentially a four step process, as follows:

Step One: I opened the image and zoomed into the tree area with the chromatic aberrations

Step Two: I created a Hue/Saturation adjustment layer by clicking the half black/half white circle at the bottom of the layers palette.

Step Three: In the Hue/Saturation tab, I then selected Magentas from the Edit drop-down.

Then, using the colour picker tools I clicked on an area of purple fringing in the photograph and dragged the saturation slider down - in this case to a value of -56.

Step Four: The final step was to make sure that I didn't de-saturate the selected colours in the rest of the image using a layer mask. This is easier than in sounds. With the Hue/Saturation layer selected, I made a selection around the tree using the lasso tool and then using a large black brush painted over the rest of the image.

If you do the same this is what you will then see in the layers palette.

The area in white around the tree has been masked out and the Saturation adjustments are not applied to the masked area.

Below are comparisons of the results from Lightroom 2 and Photoshop. You can see that the final result from Photoshop is better than that directly from Lightroom 2 which is why this technique was used.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

If you are using other software you should be able to easily find online the best approach to removing chromatic aberrations with your software.

Once the chromatic aberrations had been fixed, it was time to sort out the dynamic range issues.

>> Part Three – Fixing the Dynamic Range

Fine tuning a landscape – Part One

2009-01-01T19:25:00.012Z

A month or so ago I posted the picture below of a Shropshire landscape.

Click on the picture to see a larger version in Lightbox.
© Dominic Allkins, 2008

Overall, I am very happy with the composition of the picture for a number of reasons:

Landscapes that include the sky always (well nearly always) look better with an interesting sky. While we all love clear blue skies on warm days they generally add little to a landscape picture unless the clearness of the sky is integral to the composition.
There is a really interesting relationship between the foreground and background elements in the picture. We can see on the horizon The Wrekin (a dominant feature on the horizon in the area from just about any viewpoint) that nicely breaks-up the level horizon. In the foreground we have the lone tree in the hedge-line and the hedge itself provides a perfect 'lead line' to The Wrekin in the distance.
The sun behind the lone tree adds further drama to the scene – although this does in itself some create some of the problems that need fixing with the image.

On closer inspection there were a number of things that needed correcting in post-processing – some that could be corrected pretty quickly and some which needed a little more time and attention.

When I posted the original image I had only had about five minutes for some 'quick and dirty' post-processing so the result posted was not what it could be. I knew if I spent a bit more time then I could clean up some of the problems more effectively.

The best place to start is with an analysis of the original RAW file as it came out of the camera, highlighting the problems that needed fixing.

Analysis of the RAW file

The image below is the original RAW file straight from the camera, resized and saved for the web.

Click on the picture to see a larger version in Lightbox.
© Dominic Allkins, 2008

It doesn't take much when we look at the RAW file to see the main problems with this image when we have a look.

Dynamic Range. With the sun behind the tree (creating a very bright area) it was going to be almost impossible to expose both for the sky and the foreground. It was either a case of getting the exposure right to show foreground detail but ending up with 'blown out' highlights in the sky or expose for sky and leave the foreground under-exposed.

I chose the latter option – expose for the sky. Why? Two main reasons really; a) Over-exposed skies are almost impossible to recover in post-processing, and b) It's easier to recover detail from under-exposed areas, although doing so almost inevitably introduces another problem – noise.
Chromatic aberrations. What the h**l are Chromatic Aberrations I hear (some of) you ask? The simplest explanation is to show you. Taking a look at the 100% crop of the tree branches with the sun behind, what do we see?

Click on the picture to see a larger version in Lightbox.
© Dominic Allkins, 2008

The purple fringing around the branches are the Chromatic Aberrations. Fortunately they can be fixed pretty easily with today’s post-processing software.
Initial composition. Obviously the final image is the not the one that was shot – although not far off. I cropped the image to give, in my eyes, a more pleasing composition.

Clearly the biggest problem to deal with is the dynamic range, although with a little bit of planning it's not really that hard to deal with.

In an ideal world I wouldn't have to deal with these problems with post-processing.

Landscape photography, like any other type of photography, benefits most from a bit of pre-planning. If I had 'scoped out' the scene beforehand I would have known when the sun would be behind the tree and used a graduated neutral density (ND) filter to prevent the sky being blown out while exposing correctly for the foreground.

If you read the original post you'll know that I didn't have the opportunity to do any pre-planning (I was driving down a country road I use maybe once every other month and just happened upon the scene). Nor did I have that much time either - I had my two daughters with me in the car. They put up with me (most of the time) but I think to have had them sitting around in the car for half-an-hour while I messed around with my tripod and filters trying to get the 'perfect' shot would have tried even their patience I think.

Parts 2, 3 and 4 detail how I dealt with the identified problems with this photograph to end up with a picture that I’m really pleased with and, once I've got it framed, will hang nicely on my wall.

>> Part Two – Dealing with Chromatic Aberrations
>> Part Three – Fixing the Dynamic Range
>> Part Four – Cropping for composition

R & R at Christmas

2008-12-31T06:47:00.004Z

Well I'm back from my Christmas break just in time for the New Year celebrations. Plenty of pictures were taken which need sifting through, but I thought I'd post this for starters. It's the night time version (with extra Christmas decorations) of my pre-Christmas post and is always a beautiful sight. I'm not sure a photograph really does it justice, but without taking you all there's not much else I can do.

Click on the picture to see a larger version in Lightbox.
© Dominic Allkins, 2008

It really is a beautiful place to stand, contemplate and reflect.

Happy New Year.

Happy Christmas

2008-12-24T05:43:00.007Z

Blogging will be very light (i.e. non-existent) over the next week or so. I have had a manic couple of weeks with work that had wiped me out so am going here...

Click on the picture to see a larger version in Lightbox.
© Dominic Allkins, 2008

... for some much needed R&R over the Christmas break.

I have, however, planned a couple of shoots for while I'm away and will posting some galleries and a couple more shooting guides when I get back.

Merry Christmas and Happy New Year to all.

Dominic

The London Eye

2008-12-15T21:03:00.010Z

The London Eye is now an icon in London and known worldwide.

The October monthly challenge over Dynax Digital was night photography and attracted some great entries. It gave me the excuse to take the picture of the London Eye that I'd always wanted to but for some reason just never got around to doing.

What I wanted to do was not to 'stop' the Eye in motion but to use a long enough exposure to create a smoothed effect of the motion of the Eye.

The set up was pretty simple really. I positioned myself directly opposite the London Eye on the other side of the River Thames so the shot would be a head-on image.

The first shot

To get an idea of what exposure time I would need to use the first shot was relatively simple. I used aperture priority (set the aperture, let the camera take care of shutter speed) stopping the lens down to f16 giving me a shutter speed of 30 seconds.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

It didn't quite create the smoothing or the strength of reflection in the River Thames that I'd wanted to achieve, but certainly gave a good impression of the movement of the London Eye. It almost looks as if it is spinning round incredibly quickly.

Resetting the exposure

Since using aperture priority gave me a 30 second exposure (the maximum for the Sony Alpha 700) it then came down to using the 'Bulb' setting (see the Shutter Speed post for more info on this) to get a longer exposure. To go for the longer exposure I would need to reduce the amount of light entering the lens more than I could simply by reducing the aperture, so I used a Neutral Density filter - a grey filter which reduces light transmission without affecting the colour of the shot.

I used an Cokin P ND8 filter (which gave me three extra stops), set the aperture to f8 (the sharpest aperture for the Sony Carl Zeiss 16-80 lens I found) and calculated that I should keep the shutter open for three minutes.

Exposure was about perfect (my brain is still working then), but when I looked at the image in the screen on the back of the camera I noticed something odd. Despite the long exposure, instead of the nice smooth circle that I had expected to see, what I saw this instead looked as if the spokes and pods had been 'frozen' in place as the image was captured. Full image and crop below.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

I couldn't work out how it had happened and then was struck with a flash of inspiration while flying back from a business trip in Germany. The London Eye is very close to the railway bridge over the River Thames into Charing Cross station. The trains in that area use an electric 3rd rail to power the electric motors.

Occasionally you get a spark between the pick-up on the train and the 3rd rail (similar to that from an arc welder). In the daylight these sparks are invisible but in the dark you can see that they are very bright. I can only think that the pods were 'frozen' by a spark from the 3rd rail.

But eventually I got the shot that I wanted to enter the challenge. There were some great shots entered into the competition and I was very humbled to have my entry voted as the winner :-)

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

An alternate view

After taking the shots from Embankment I walked up onto the east Hungerford footbridge to get a shot of the City of London at night. When I turned around from the city I saw this interesting composition of the London Eye, the railway bridge and one of the supports for the west side footbridge. No cropping at all, just tweaks in Adobe Camera Raw.

I'd already removed the adapter for the filter and was getting cold (I know, I'm a lightweight) so decided just to shoot without the filter, knowing I wouldn't get the complete smoothing of the rotation of The London Eye. I still like this, particularly the impression of movement of the Eye. It was almost the shot submitted for the challenge - a very close decision. The dots you can see in the sky are an aeroplane flying across the frame during the exposure.

I've also included the shot of the City of London looking East, away from the London Eye.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

I hope you've enjoyed the background story to the shoot.

What I've hoped to get across is that planning ahead can often give the best results. I'd thought about the result I wanted to achieve and set a plan to do so. We can't always plan ahead in this way, but if you can, try and do the planning. It pays.

Speed reading and language

2008-12-14T13:20:00.007Z

This made me chuckle.

Over at Dynax Digital there's currently a discussion thread about the going rate for magazine photography. One of the comments in the thread contains the following quote:

I shot the neighbors two months ago as a favor

I missed the obvious (non-photographic) alternative interpretation when I first read it until someone pointed it out. Can shooting people be seen as a favour?

UPDATE:

To which someone has added:

I have to admit, I shot my parents-in-law the other day, and everyone liked the result, and my wife was quite happy about it, too.

I think I'll leave it there for now, but keep checking the post as I suspect there may be more funnies being added

Sony α700 vs. α900

2008-12-14T12:08:00.006Z

I decided recently to take the step up to a full frame dSLR – moving from the α700 to the α900, paired with the Sony Carl Zeiss 24-70 lens. A major commitment (financially if nothing else) as the move from APS-C sized sensor to a full frame sensor does for various reasons have to make you think more about what you’re shooting . The most obvious consideration is the reduction in depth-of-field with full frame.

Having got the α900 home I then set about testing it against α700 to check out the difference in the results between the cameras.

Suffice to say, the results from the test blew me away.

The test set up

I have a great view over the town where I live from the balcony at my apartment, which also happens to provide an ideal test subject for a test such as this.

Both cameras are set up in exactly the same way. ISO200, Auto White Balance, Spot focus, Spot metering, RAW only, standard creative style, no in-camera sharpening. Pretty much as clean as you can get.

The only difference between the two was the lenses tested; I used what would be the 'standard' zoom for each camera - the Sony Carl Zeiss 16-80mm on the α700 and Sony Carl Zeiss 24-70mm on the α900.

The focal lengths tested were 45mm (67mm equivalent on full-frame) for the α700 + CZ16-80 and 70mm for the α900 + CZ24-70 set up – keeping the comparison as close as possible with regards to focal length.

The exposure reading was taken with the α900 + CZ24-70 and manual exposure was used for both cameras to ensure that the exposure was exactly the same for each shot.

All shots were tripod mounted with SteadyShot turned off. The focus point for all shots was the clock on the church tower.

The RAW files were imported into Adobe Camera Raw (ACR) and exported with no sharpening or noise reduction applied (ACR has defaults set for sharpening and noise reduction which I had to dial down).In effect, the results are pretty much straight out of the camera.

The full shots

The two images below are the main images; the left image is from the α700 + CZ16-80 and the right image from the α900 + CZ24-70.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

Comparing the two online, there appears to be little difference. Both are nicely exposed with plenty of detail. You'd expect this – both set-ups are great camera/lens combinations.

What these images don't show is what blew me away when I first opened them up and compared them at 100% in ACR. The level of detail and resolution from the α900 + CZ24-70 is incredible. Below are 100% crops of four areas of the images that allow you to see how different the two images are.

Click on any picture to see larger versions in Lightbox.
© Dominic Allkins, 2008

Summing up

I was using different glass for each camera, but that was very deliberate. The CZ16-80 is about the best wide to short telephoto zoom available for the α700 and likewise the CZ24-70 is the same for the α900. I tested this way as these are most likely to be the principle standard zooms employed on each of the cameras respectively and thus the test compares what the typical set up would be for each camera.

It's simply not possible when posting images online (reduced in size) to truly grasp how amazing the images from the α900 are when compared to the α700. As I said, seeing them at 100% on my monitor for the first time blew me away. The α700 does produce great images but I was not prepared for how much better those from the α900 would be. It's not just marginal, it's magnitudes. It's not a great analogy, but it's a bit like comparing a pro golfer ranked 25th in the world (still one of the best golfers around) and Tiger Woods.

So why go for the α900?

If all you’re doing is posting images online, using them in a digital photo frame or producing small prints to go in an album then the α700 + CZ16-80 is a great camera/lens combination that will give you fantastic results.

If, however, you’re making larger prints or looking to sell images (either via a stock library or directly) then the α900 + CZ24-70 really is the way to go. Obviously I can’t show you online just how good an A3+ print from the α900 is, so you’re going to have to trust me on this one – just incredible.

What of the α700

My original plan was to keep the α700. The APS-C sized sensor would give me longer depth-of-field than the full frame in the α900, plus the 1.5x magnification factor of the APS-C sized sensor means the focal length of zoom lenses are extended, giving me more reach. Both very good reasons to hang to the α700.

But after this test I looked at the α700 and thought to myself “Would I ever deliberately pick up the α700 over the α900 when go out for a shoot?” The answer to that question was “No” – I just couldn’t see myself making that choice.

So the α700 has gone.

The α700 + CZ16-80mm did give me some really great pictures and if you’re thinking of buying one then rest assured, it will do the same for you. It really is a very good camera/lens combo.

All the results of this test show is the step up that goes with the move from APS-C sized sensor to full frame and from 12.2M pixels 24.6M pixels.

UPDATE: Someone has posted a very interesting article over at DP Review comparing the Sony α900 with a Hasselblad H1-P30. An interesting comparison with a very interesting result.

You can read further discussion of the comparison over at my favourite forum, Dynax Digital

Shooting the moon

2008-12-13T07:09:00.016Z

Apparently last night (Friday 12th Dec 2008) was supposed to be the closest moon since 1993 so it would have been a great night to get a nice detailed shot of our nearest celestial neighbour.

Of course, that relies on the weather behaving itself and us having nice clear skies. Fat chance - it was complete cloud cover and tipping down with rain!!

However, Thursday night was perfect when I got home - a beautiful, crisp (i.e. very cold), clear winter evening. So I decided to give it a go with my new Sony A900 full frame with 24 mega-pixels paired with the Sony 70-300 G SSM lens @ 300m, and here is the result.

The incredible thing for me is the amount of detail that is retained by the A900 even when cropping this dramatically. Absolutely amazing! In the original frame the moon itself only occupied the small circle in the viewfinder around the centre focus point, and yet very fine detail is retained in the crop. It's worth noting that the crop is actually a 100% crop, i.e. it's pixel for pixel from the original shot.

So the weather prevented me getting a picture of the closest/biggest moon for fifteen years, but I'm still very happy with the result that I got :-)

Tips for shooting the moon

If you want to take pictures of the moon, make sure you do the following:

Mount the camera on a good sturdy tripod
Position the moon right in the middle of the frame, over the centre focus point. This also ensures that the moon is right in the sweet spot of the lens.
Use spot focussing
More importantly still, you MUST use spot metering otherwise your exposure will be well off
Use mirror lock-up or a 2 second self timer combined with a remote release so that you're not introducing even minute camera shake by pressing the shutter button on the camera
Go!

White Balance - Why it's important

2008-12-07T10:19:00.024Z

Aperture, shutter speed and ISO are generally thought to be the three factors that affect exposure when taking photographs. There is a fourth factor, White Balance, which is probably the least widely known about and almost certainly the least understood setting on most cameras.

In the posts about aperture, shutter speed and ISO I gave brief explanation about what each of the settings are before getting into the detail of how those setting s affect exposure. For this post I'll dive a little deeper into what White Balance is to help give a better understanding of why it is always important to check and set white balance correctly when taking your pictures.

What is White Balance

The science behind White Balance involves some pretty complex mathematics and physics (which, you'll be very pleased to know I don't intend to go into here). At the bottom of this post you'll find links to relevant pages on Wikipedia that provide much more detail.

In layman’s terms (that'll be me then) all light/light sources have a colour temperature (normally expressed in Kelvin – K for short). This colour temperature has a direct impact on how light and most particularly colours are captured by our cameras’ sensors when we take photographs.

To give an idea of the range of colour temperatures for different light sources, the table below gives an outline of light sources with the (approximate) corresponding colour temperatures.

Light source	Colour Temperature
Candlelight	1,000-2,000K
Tungsten (household) bulb	2,500-3,500K
Sunrise/Sunset (clear sky)	3,000-4,000K
Fluorescent lights	4,000-5,000K
Camera Flash	5,000-5,500K
Daylight with Clear Sky (sunshine)	5,000-6,500K
Moderately overcast	6,500-8,000K
Shade/heavily overcast	9,000-10,000K

Hopefully what the table does is give a clue to why white balance is so important when taking photographs. In essence, if you take your pictures with the wrong white balance setting, you'll get a nasty surprise when you load you pictures onto your computer.

If you're taking pre-planned pictures which you can go back and take again, that's fine. But what about those from a wedding or a holiday. These are a one-time only occasions – you can't go back and ask people to go through the whole wedding again just because you got your white balance wrong.

There are in fact three solutions to this problem:

If you’re shooting JPEG or TIFF files, get your white balance right first time.
Just in case you didn’t get that, if you’re shooting JPEG or TIFF files, get your white balance right first time.
Shoot in RAW format, not JPEG or TIFF. I’ll be posting a separate article soon about the importance of RAW format, but for now all I’ll say is that with RAW you set your white balance after you’ve loaded your pictures onto your computer.

I know the above is actually only two solutions, but getting your white balance setting right if you're shooting JPEG or TIFF is so important it really does justify the repetition. With most digital cameras it takes no longer than a couple of seconds to set the white balance – but the impact of getting it wrong lasts forever.

How you set the white balance on your camera is likely to be specific to the camera model or the manufacturer, so I won't try and take you through setting the white balance on your camera. Grab your manual and read away.

Both my dSLRs (Sony Alpha 700 and Sony Alpha 900) have two very quick and easy controls for setting white balance. I can even set difference white balances on my little point-n-shoot Olympus µ[mju:] 1030 SW.

For most dSLRs the white balance options are: Auto, Daylight, Shade, Cloudy, Tungsten, Fluorescent, Flash and Custom. Point-n-shoot cameras generally offer fewer options so worth checking out your own camera.

Why White Balance is important in photography

So let's assume that you're either not shooting in RAW with a camera that has that function (why?) or your camera doesn’t have a RAW capture function.

As mentioned above, the colour of the light in which you're taking your picture will affect how the sensor of your camera captures that light. With the wrong white balance, you’re likely to get a colour cast on your pictures – particularly so if you set tungsten as your white balance while shooting outdoors in daylight (see the examples below).

Having the wrong white balance setting also has the potential to affect the overall exposure of the image and the ‘warmth’ of the colours in the final shot.

The following examples were all shot from the balcony of my apartment looking down at the park below. It was a bright, sunny, frosty December morning.

The camera settings, which were (almost) identical for every shot except for the white balance setting, were: Sony Alpha 900, Sony Carl Zeiss 24-70mm at 70mm, aperture priority f8, ISO200, pattern metering. For each image I've included the shutter speed (so you can see how white balance affects exposure) and also comments about the change in image appearance.

Given the conditions the Auto White Balance setting has done a pretty good job. It's not that surprising really as camera manufacturers have had years now to refine how this works. But auto won't always get it right. In trickier conditions than these (i.e. with variable light and perhaps even different light sources) auto can be 'tricked out' and apply the wrong settings.

Setting custom white balance can help avoid any problems.

I use a ColorRight White Balance disc for measuring the light when I'm shooting, but there are different methods so have a Google to find the options. Also, each different camera will require a slightly different method of setting custom white balance.

If you plan to go down the route of using custom white balance settings (which I would definitely recommend) then the best thing to do is dive into your camera manual and practice until you can do it without thinking. It will add only a few seconds to your shooting but will make a significant difference to the results.

This is a long post, but with White Balance being such a complicated subject I wanted to make sure that there was enough explanation in here to help you take better pictures.

Wikipedia links
Colour balance
Colour temperature

Shutter Speed

2008-12-06T19:32:00.016Z

Shutter speed is the term used to describe the amount of time that light passing through the lens is allowed to hit the camera's sensor. Fast shutter speeds mean that the sensor is exposed to light for a shorter amount of time and vice-versa.

Shutter speed and ‘stops’

As with apertures, shutter speeds are measured in 'stops' and represented by fraction values of time. For the Sony Alpha 700 that I use, the 'standard' or 'full' stop shutter speeds are: 30s, 15s, 8s, 4s, 2s, 1s, 1/2s, 1/4s, 1/8s, 1/15s, 1/30s, 1/60s, 1/125s, 1/250s, 1/500s, 1/1000s, 1/2000s, 1/4000s, 1/8000s.

In effect, each stop change in shutter speed either doubles the amount of time the shutter is open and the amount of light allowed by the shutter to hit the sensor (i.e. from 1/60s to 1/30s) or halves the time and light permitted to hit the sensor (i.e. from 1/30s to 1/60s).

As with aperture, the advent of the digital age (or more accurately digitally controlled shutters) means that we now have intermediate or half-stops between the standard full-stops that gives us a bit of extra fine tuning. For the Sony Alpha 700 these are: 20s, 10s, 6s, 3s, 1.5s, 0.7s, 0.3s, 1/6s, 1/10s, 1/20s, 1/45s, 1/90s, 1/200s, 1/350s, 1/750s, 1s,1500s, 1/3000s, 1/6000s.

This incredible range of shutter speeds delivers a huge amount flexibility when shooting. At the slowest shutter speed (30s) it's just about enough time to go pour a nice glass of wine (if shooting indoors) while waiting for the exposure to finish, while at it's fastest (1/8000s) the shutter moves about 2,400 times faster than the average eye blink (approx 0.3s).

The final shutter speed setting is called 'Bulb' which I'll cover in more detail below.

Stopping the action

In most cases with our photography we want to ensure that whatever it is we are shooting is as sharp as possible. The simplest way to do this is to use faster shutter speeds, decreasing the chance that either subject movement or camera shake ruins the shot.

Over at Dynax Digital one of the most prolific photographers is Clive Schaupmeyer who specialises in taking pictures of flying birds (I figured shooting wasn't the most appropriate word here). Clive recently posted a great series of images demonstrating how shutter speed affects the end result when capturing birds in flight and with kind permission I have reproduced them here. Thanks Clive.

Click on any picture to see larger versions in Lightbox. These images are © Clive Schaupmeyer, 2008 and have been reproduced here with Clive's permission.

But stopping the action doesn't always mean that everything in the image has to be tack sharp. We've all seen pictures in newspapers and magazines of racing cars (or other moving objects) where the subject is nice and sharp again a blurred background - panning shots. Paul O'Toole, another contributor to Dynax Digital, recently and very deservedly won the November 2008 Photo of the Month award with a panning shot of a motocross bike jumping. Paul has kindly allowed me to use the image here to demonstrate the effect. Thanks Paul.

Click on the picture to see larger versions in Lightbox. This image is © Paul O'Toole, 2008 and has been reproduced here with Paul's permission.

Capturing motion

Some of the most dramatic shots we see are when motion is captured through longer shutter speeds. I recently posted a gallery of shots taken at a fun fair I attended with one of my daughters (the other one was spending the day with her new boyfriend ;-) ). You can see the full gallery here but below are a couple of shots as an example of the effect.

Bulb - isn't that something that lights a room?

Yes - but not in this case.

The bulb shutter speed setting is used for longer exposures than the pre-defined shutter speeds allow - in the case of the Sony Alpha 700 I use, longer than 30 seconds. The term bulb originates from when camera shutters were manually activated with an air bulb - simple really. The only real difference now is that we set bulb in the cameras menu and use an electronic switch to keep the shutter open. Bulb exposures can produce some of the most dramatic pictures of subjects such as fireworks, car light trails, lightning or stars in the night sky.

The shot below of the London Eye was taken using a three minute exposure from the opposite side of the River Thames. It was taken for the October 2008 Night Photography monthly challenge over at Dynax Digital and I'm proud (and humbled) that it was voted the winning shot by other members of the forum.

Of course for longer exposures such as these the most important piece of equipment to use (apart from the camera obviously) is a tripod - something that I'll discuss the importance of in a later post.

Hopefully the above has given you a good idea on what can be achieved by changing shutter speeds to suit your creative need. I'll be covering 'creative exposure' in a separate post.

Thermal Weapon Sights - Huh??

2008-11-24T06:57:00.014Z

I had a quick look at the blog this morning, as you do, and I happened to notice the content of the Adsense box in the right column - screengrabbed below.

It seems that BAe Systems are short of customers for aiming systems for Thermal Weapons and have therefore decided to use Google Adwords to drum up some business. Huh? What's that all about?

Raises a couple of questions though:

Surely BAe Systems know who all the world's weapons systems manufacturers are? Maybe not - maybe there are some people out there making these weapon systems in their back bedrooms? Who knows?

Will the fact that I appear to be advertising components for weapons systems result in SWAT teams crashing through my door to arrest me and ask why I'm carrying such advertising?

All very odd really, given this is a blog about photography.

All the fun of the fair

2008-11-23T16:11:00.009Z

I was with out with my younger daughter over the weekend and the Christmas lights were being turned on. There was a lot of different entertainment to accompany the turning on of the lights including a fun fair. Had I known the fair was happening I'd have taken my tripod, although I'm not sure how Meg would have reacted to me lugging that around all day.

So without the tripod I decided to get a bit more creative and try to show the energy of the two main rides of the fair with some hand-held shots - capturing the motion of the rides with a bit of panning.

Enjoy.

Aperture

2008-11-23T14:47:00.015Z

Put simply (and some might argue rather crudely), aperture is the hole in the lens that lens the light through to the camera sensor.

There is a very good explanation of the technical aspects of aperture over on Wikipedia so I won't go into too much detail here. The aim of Visible Pixels is to (hopefully) help you understand how use of aperture (and all the other settings on your camera) can help you take better photographs, so that's what we'll concentrate on.

To change the aperture (i.e. amount of light you let through the lens) all you need to do is to change the f-number on your camera.

Big aperture = small f-numbers. What's going on there then?

Common sense would suggest that the lower the f-number (or f-stop) you set in the camera the smaller the hole in the lens and vice-versa. But how often has common sense defined things in life, never mind photography?

The f-number itself is a function of the equation that describes aperture, which is very well explained in the Wikipedia article.

All you really need to remember is that the smaller the f-number you set (e.g. f1.4), the bigger the hole in the lens and more light is allowed to pass through the lens to the camera sensor.

Standard and fractional f-stops

There are a set of standard f-stops that are defined by the aperture equation. These are: f1, f1.4, f2, f2.8, f4, f5.6, f8, f11, f16, f22, f32, etc... I can hear you saying now, "How the hell am I supposed to remember that?" The easy way to remember these standard f-stops is to double the number of each alternative f-stop - you'll see I've highlighted in red the even stops that demonstrate this (note f-stops get rounded).

More often that not with modern digital SLR cameras and lenses you'll have f-stop values in between these standard stops. For example, on my Sony Alpha 700 with the 'standard' 50mm f1.4 lens the f-stop values are: f1.4, f1.7, f2, f2.4, f2.8, f3.5, f4, f4.5, f5.6, f6.7, f8, f9.5, f11, f13, f16, f19 and f22. You'll see from the green figures that I have an effective extra 'half' stop between each full or standard f-stop.

Why is this important?

If you leave your camera in full auto mode then it's not important and you won't have to worry about any of this (or any of the other exposure posts come to think of it).

However, if you want more control over your pictures you'll often finding yourself having to re-calculate exposures based on f-stops to get the 'correct' exposure. When you do this recalculation, you need to make sure you use the full or standard f-stop values, not fractional stops. For example, if my exposure settings were 1/125s shutter speed and f5.6 aperture, if I deliberately wanted to under-expose by two stops (using aperture) then I would have to re-set my aperture to f11.

If I included the fractional stops as part of this calculation then I would be re-setting aperture to f8 and would end up with a picture that is one stop over-exposed against my objective.

NOTE: Exposure can also be adjusted using shutter speed which I cover in the shutter speed post.

Aperture and depth-of-field

One of the biggest impacts of different aperture settings is how the depth-of-field is affected (i.e. how much of the picture is in-focus from front to back). With aperture 'wide open' (low f-number, big hole) depth-of-field is significantly reduced whereas 'stopped down' (high f-number, small hole) depth-of-field is greatly increased.

The four shots below were taken from my balcony to illustrate this point. These are the JPEG files straight from the camera with no adjustments that might affect the results.

The first two pictures were taken focused on the edge of the roof by the double door in the wall facing us. Picture one was taken at f1.4 (aperture wide open) whereas picture two was taken at f22 (aperture shut down). In picture one (f1.4 wide open) we can clearly see that the door is in focus while the rooftop at the bottom right is out of focus. By stopping the aperture right down to f22 depth-of-field is increased and the roof-line at the bottom right is sharply in focus.

The second two pictures were taken with the same composition, this time pre-focusing on the roof-line and re-composing. Again, the first picture was take wide open (f1.4) with the second picture taken fully stopped down (f22). The results are similar to the first set of two pictures, only this time we're looking at whether the background is in-focus. For this set, we can see that while the roof-line is nice and sharp in the first picture with the aperture wide open, the apartment building in the background is out of focus. Conversely, fully stopped down both the roof-line and background are in-focus.

I'll cover depth-of-field and it's importance in greater detail in forthcoming posts. For now, when you're composing your shots have a think about the depth-of-field that you might want to achieve and adjust your aperture accordingly. Better still, takes pictures at different aperture values while you're out shooting and look at the effect of changing aperture yourself. Not only will you get to understand the aperture/depth-of-field balance for your particular camera and lens combination but you'll also have a good variety of shots to choose your keepers from.

The simplest way to do this is to shoot in 'Aperture Priority' mode - a semi-automatic mode that ensures 'correct exposure' by automatically changing shutter speed as you manually adjust aperture.

ISO – getting sensitive

2008-11-18T11:28:00.011Z

What is ISO?

ISO is one of the three core components of achieving 'correct exposure', along with aperture and shutter speed. I'll be covering correct exposure, aperture and shutter speed in coming posts – for now I want us to get sensitive.

In the pre-digital age, films came in different speeds or sensitivity to light - the higher the ISO the greater the sensitivity to light of the film. It meant that whenever a film was changed, if the new film was a different speed then the ISO setting on the camera had to be changed to match the film speed.

The only real difference in ISO setting between film and digital cameras is that with digital we don't have to change sensor every time we want to increase or decrease the sensitivity of the camera to light (thank goodness); all we're doing is telling the processor in the camera how sensitive we want it to be for the ambient light conditions or the subject we're shooting.

Adjusting ISO for light conditions

In low-light conditions (e.g. shooting indoors with natural light or around dawn and dusk), less light makes its way through the lens to the sensor. To avoid under-exposed (dark) images we therefore need to increase the sensitivity of the sensor in the camera to help us.

Conversely, in very bright conditions, we can reduce the sensitivity of the sensor to get great pictures.

Adjusting ISO for the subject we’re shooting

Imagine you're at your local football (soccer)/rugby/cricket/etc... (delete as appropriate) and you want to get some shots of the action. It's quite likely that you'll need to use a telephoto or long zoom lens to capture distant action and light conditions are not always ideal.

Increasing the ISO (sensitivity of the camera's sensor) allows you to use much faster shutter speeds and avoid lots of blurred shots of the sportsmen.

However, if you're in the studio or shooting static objects and shutter speed is less important, you can dial down the ISO and the final images will have much greater detail.

Huh? Much greater detail?

In film photography, higher ISO meant more image 'grain' and therefore less detail in the image. On the other hand, the lower the ISO, the finer the grain and the more detailed the image.

The equivalent in digital cameras is image noise, which is a whole topic in itself and one I'll come onto in a follow-up post.

Every camera exhibits different noise characteristics as the ISO level changes, so I'd recommend experimenting with your own camera so you know how your own camera's noise varies based on ISO setting and are prepared for your shooting.

As a (very) simple rule-of-thumb for now – if high-quality images and fine detail are critical then set a lower ISO. But if fast shutter speeds are required then dial up the ISO to increase the sensitivity of the sensor.

It doesn't have to be expensive

2008-11-15T20:10:00.010Z

I do most of my shooting with my Sony Alpha 700 - it's a great camera which produces spectacular results, but there are occasions and places where it just isn't practical to take the Sony. Sometimes it's the size and at other times I'm in a situation where I just don't want to risk the Sony.

For that reason I also have a little 'Point n Shoot' camera, an Olympus µ[mju:] 1030 SW - the bouncy waterproof camera from the TV ad.

It goes without saying that the image quality from a 'Point n Shoot' isn't as good as from a digital SLR, but that doesn't mean that good results can't be achieved - far from it.

The pictures below was taken whilst sailing in the 2007 Three Rivers Race during a quieter moment when I had the chance to get the Olympus out. I love these pictures.

The first is what I spend most of my time looking at when sailing. The contrast between the sails and the blue sky is lovely.

The second and third are looking forward as we make our way up the River Thurne towards Hickling Broad. The sailing cruiser that overtook us is a very quick boat which I've been fortunate enough to crew several times and after passing us she just disappeared into the distance.

What these pictures show (I hope) is that it's not the camera that makes a good photograph, but the person and the imagination behind the lens. It's the creative eye that sees the shot - all the camera does is record it to remind us in the future of what it was stirred our emotions enough in the first place to take the picture.

Posting these in the winter with the boat out of the water for it annual maintenance makes me yearn for the long, cold, dark months of winter to pass, for spring to arrive and to get back on the water.