For a while I have been meaning to use my Canon EOS 600D DSLR to get a shot of Messier 13, the cluster in the constellation of Hercules, but since I had my LX-modified SPC900NC webcam already hooked up to the scope, I thought I would slew to M13, and see what kind of image I could get using the webcam before replacing it with the DSLR camera.

The resulting shot is a stack of 10 x 30 second lights (unguided) taken using K3CCD software with the webcam set to Long Exposure mode, and 5×30sec darks stacked and subtracted. Aligning and stacking was performed in K3CCD, and the final BMP image was saved at which point I tried Photoshop to process it.

M13 Cluster

I wasn’t happy with the sharpening in Photoshop, so I started again with the BMP and this time post-processed using Nebulosity 3 to apply levels/curves, adjust background colour, sharpening with unsharp filter, plus Star Tightening filter and GREYCstoration noise reduction. I also attempted using DDP as an alternative to levels/curves, but this looked messy and over-processed. I much preferred the more natural look without DDP, although for some images DDP can work wonders.

After taking the webcam images I went indoors to get the DSLR, but by the time I had removed the webcam, then connected the DSLR with T-adapter to the scope, plugged the USB lead to the laptop and fired up BackyardEOS, I looked up again and found that a light cloud covering had rolled in - those pesky sneakin’ clouds! So the comparison shot with the DSLR will have to wait until another night.

After some investigation (and it seems quite a few other people on forums get confused about what is possible) it turns out I am able to use the standard RS232 serial cable supplied with my Synscan Upgrade kit when the mount is set to use PCDIRECT mode.

Normally I use this standard cable with a USB to Serial converter plugged into the bottom of the SynScan Hand Controller unit to allow planetarium software like Carte du Ciel or Stellarium to control my mount via the Celestron ASCOM driver.

It turns out that EQMOD can also use this cable to control the mount. Well this would seem to be the logical conclusion wouldn’t it? Planetarium software can control it, so why not EQMOD too? This is where the confusion sets in!

When I first started reading about EQMOD I got the impression that it had to use a special adapter cable plugged directly into the Hand Controller RJ45 socket on the mount (without the hand controller in use at all) and via an electronic box called an EQDIRECT adaptor, but depending on where you get this from, and get the cables required on either side of it, the cost can be anything from £40 to £80, although you could build the unit yourself to reduce the cost. Well I’m going to tell you the cheapest and easiest way of making this cable (about £13+delivery). By the way, all this information is available on the EQMOD site.

EQMOD works in a different way to other software because it communicates with the mount electronics more directly, rather than going via Celestron driver software thru the hand controller. This means control signals are quicker and more accurate.

The EQDIRECT adapter is designed to convert the voltage levels to operate the mount when connected in this “direct” way, and it also protects both the laptop and the mount from electronic damage if you plug them incorrectly. Places like Shoestring Astronomy build such a unit, and supply the required cables, but technology has moved on and there is actually a simpler and neater type of cable which does away with the EQDIRECT “box” altogether (although it is still referred to as an EQDIRECT cable, because simply put “it is a cable used by EQMOD to plug directly into the mount“).

Anyway, back to the point. I was excited about trying EQMOD, but it seemed as though I would have to fork out a bunch of money, and wait for a cable and adapter before I could do so.

The standard cable can not be plugged directly into the hand-controller port on the mount! It is not designed for this, it has an RJ11 male connector anyway, and could damage the mount electronics if you added some kind of RJ11 to RJ45 adaptor plug.

METHOD A - using PCDIRECT:-

This is where PCDIRECT comes to the rescue - although it is recommended that this method is used only for trying out EQMOD. For long-term use the special EQDIRECT cable described above should be obtained instead (more on this in a moment).

PCDIRECT mode sets the hand-controller unit to pass these different signals from EQMOD straight through its circuitry to the mount, effectively bypassing any interaction with the hand controller unit itself. In a way PCDIRECT mode acts as if it were a simple EQDIRECT adapter cable!

The trouble with PCDIRECT is that if you were to try also to use the hand controller functions to control the scope, e.g. slewing, or the tours, etc, both the hand controller (plus any other software using ASCOM normally) and EQMOD could get very confused about where the scope is pointing, or they might corrupt the control signals being passed. Certainly not what you want if you have spent time aligning the scope. So this is why you should get a proper EQDIRECT cable if you intend to use EQMOD seriously.

The good news is that PCDIRECT mode can be used by plugging the standard cable into the bottom of Synscan (or Celestron) handcontroller as normal (in the RJ11 port), and then set PCDIRECT mode on, which can be found in the Utility menu.

Assuming you’ve installed EQMOD+EQASCOM followed by the latest ASCOM Platform 6SP1 from the ASCOM site proceed as follows:-

Plug standard USB>Serial adaptor+RS232 cable into the RJ11 on Handcontroller.

Turn on the mount, press Enter on the hand controller multiple times quickly to skip thru the Date,Time, Lat/Long settings accepting whatever values were already there, it really doesn’t matter, and after the Polaris hour-angle display press 2)NO to ignore alignment. This leaves you with the SETUP> menu displayed.

(No settings/alignment need to be done, PCDIRECT mode is a dumb passing of signals, it doesn’t care about anything set or controlled by the firmware in the hand controller. EQMOD is the only thing you need to work with. You perform everything in EQMOD; date/time set by the laptop, geographical lat/long from manual entry or better a USB GPS plugged into the laptop, slewing by mouse/keyboard control or better a USB or bluetooth gamepad, polar alignment with EQMOD as an aid to accurately setting hour-angle, and sky alignment in conjunction with the Sync function in planetarium software using as many stars as you wish, 1,2,3 or up to 1000).

Choose Utility menu, scroll to PCDIRECT, and press Enter (shows message “PC Direct Mode: Press ESC to exit“, leave like this, and don’t touch the handcontroller until the end of your nights session).

One time setup:-

1. Run Start>EQMOD>EQASCOM>EQASCOM Toolbox.
2. Choose EQASCOM, click Driver Setup button. Mount options Type should be SyntaEQ (no need to change/set Custom mount RA/DEC).
3. In EQMOD Port Details you should only need to change the COM port to match. Timeout(1000), retry(1), Baud(9600) remain as standard. Note the Find (binos) button sometimes fails to detect the mount (ignore this).
4. Click OK (setup closes).
5. Click Test Connect (this should work) and…
6. EQMOD ASCOM EQ5/6 window opens and will be flashing PARKED. Click UNPARK.
7. Click the “star” button and you should hear the RA motor start tracking.
8. Choose Rate 4 from the dropdown, sets rate 800 for both RA & Dec.
9. Click N,E,S,W and should slew proving working ok.
10. Click Park, then in the Toolbox screen click Disconnect.
11. Exit Toolbox.

Should now be able to Start>EQMOD>EQASCOM>EQASCOM_Run for normal operation.

METHOD B - For EQDIRECT cable:

I purchased my EQDIRECT cable which is a TTL-232R-5V-WE from EasySync Ltd for £12.99 (the linked page has tech docs and USB driver downloads). This cable has a miniature FT232RQ converter chip built into the USB plug end of the cable (the equivalent of what is in the larger/older style EQDIRECT junction boxes). It provides TTL level signals at 5 volts (5V).

The -WE (on the end of the part number above) means bare wire-ended (i.e. without any kind of connector on it), and this is the only bit of making up that is required. You need to find a techy friend, computer shop or someone who makes up network cables who has a tool that can crimp an RJ45 male plug onto the wire end of the cable. The stripped wires are slightly too thick to go into the RJ45 wire holes, and need thinning just a little and then tinning with solder, to insert into the RJ45 plug ready for crimping. It’s a little bit fiddly to get it just right, but well worth doing this relatively simple job to save your money.

Only the Black (Ground), Yellow (RX) and Orange (TX) wires are necessary, the other 3 can be cut-back making sure they cannot short together. On the RJ45 plug Black goes to pin 4, Yellow to pin 5 and Orange to pin 6, as detailed in the diagram at the bottom of this EQDIRECT page. (Note: I messed up first go, and crimped shorting a couple of the wires because I had pushed them in too hard, so had to cut off the plug, strip back and retry with a new RJ45. Second go worked, and had not caused any damage).

You now have a single neat EQDIRECT cable without any bulky adapter box mid-way.

You will need to download and install the USB driver software from the links available on the purchase page at EasySync. Note the benefit of the driver is a static COM port number, which conveniently remains the same number even if plugged into a different USB port.

Plug your new EQDIRECT USB>RS232 TTL lead into the USB port and into the RJ45 on the mount normally used for the HC (the Handcontroller will not be plugged in at all).

Turn on the mount (no beeps since the HC usually emits sound, but isn’t connected).
Follow steps 1-11 exactly as above except choose the COM port for the new lead.

In Cartes du Ciel for Scope connection, select EQMOD ASCOM EQ5/6 (if EQASCOM_Run is not already running CdC will start it up).

Note that it is generally better to start EQASCOM_Run manually (will show in Systray, where it can be Exited when finished). This means it runs continually, rather than being auto started and stopped by other software using the mount, which occasionally leads to problems.

Disclaimer: While this article aims to be helpful and may apply to other popular mount types, I accept no responsibility for inaccuracies or damage resulting from incorrectly matched cable types. Please ensure you order the correct items for your particular mount by completing your own research.

NGC869 part of Double Cluster

However, while it is quite necessary to take the time to read the manual to know what to do, and I have learned a tremendous amount by doing so, the manual is fairly long (it’s a good thing), I felt that it lacked a simple crib-sheet to remind you of the basic steps without having to paw through the manual over again….

So I wrote the following basic notes for what to do:-

(This process is for one-shot colour camera in RAW mode, such as my Canon EOS600D, but can be different for other cameras, e.g. mono, unsquare/square pixels, etc.)

• Create Master Darks or Bad Pixel Map (BPM), Biases, Flats: Menu>Batch>Align and Combine. Use Average/Default or Std Deviation, alignment=None(fixed). Select all dark frames. Save/name as Master_Dark_<exposure-time>_stack.fit.
• Filter out obviously bad Light frames: File>Preview Files. This is a manual review process, (different to Grading which can be done later) and will save processing time if dud lights are removed now (rename as bad_*).
• Apply Darks/BPM/Biases/Flats to Lights: Menu>Batch>Pre-Process Image Sets. (Dark subtraction works better before converting to colour). Gives pproc_*. (If using traditional Dark subtraction, no need to subtract Bias, but if using Bad Pixel Map need to subtract Bias too).
• Normalizing (optional): Standard deviation-based stacking is better when Lights have equal brightness. Menu>Batch>Normalize Intensities. Select pproc_*, gives norm_*.
• Colour reconstruction (Debayer / Demosaic): Menu>Batch>Batch Demosaic+Square RAW colour. Select norm_*, gives recon_*.
• Grading images (optional, helps decide to use only the sharpest images): Grading images works better after debayer/demosaic. Gives Qnnn_*
• Stacking: Menu>Batch>Align and Combine. Alignment=Translation. Stacking=Average/Default. Select recon_* (or Qnnn_* if you Graded). Pick best bright but not huge star (not saturated/faint/noisy). Click it. Next image, click + (Shift=skip, Ctrl=keep guess, Alt=auto all). Repeat til done. Save as avgstack_v0. (If hot pixel streaks appear in final stack, try Standard Deviation method instead).
• Post-processing:-
• Crop.
• Adjust Background Colour Offset (optional, removes skyglow).
• Save!
• Stretch (Levels, DDP, Curves,etc).
• Save!
• Adjust Colour, Hue Saturation, Noise reduction, Blur, Sharpen, etc.
• Post-processing in Photoshop.

M27 Dumbbell Nebula

Even so there were a few things wrong with trying to get this image…..

For instance both the DEC and RA axis have quite a bit of backlash on my Synscan EQ5 mount (it needs adjusting) and because I didn’t give a bit of weight bias to make the RA axis motor work to pull the counter-weight “uphill”, so to speak, the gears were pushing the mount to a certain tipping point, then gravity caused the weight on the scope+camera side to “topple” downhill. This was only by the tiniest amount of the backlash distance in the RA worm gear as the RA mount gears teeth shifted between the worm gear teeth, but this was sufficient and regular enough to cause all the stars to suddenly create a streak during the 2 minute exposures I was using for this image. I didn’t realise this until the next day when I went to process the images.

I think the same backlash problem is also contributing to poor polar alignment when I try to use Alignmaster because when trying to perform the aligning process as instructed by Alignmaster, I cannot re-position the chosen alignment stars in the centre of the reticule properly (I use a webcam and Sharpcap for this purpose). So this contributes to some drift in this image (slightly elongated stars), because as yet I don’t have the kit to perform proper autoguiding, although I have done some experimentation with the free PHD software.

Out of the 11 shots I had taken (using my recently acquired Backyard EOS to control the camera), I found that only 4 of the set could actually be used for pre and post-processing in Nebulosity 3. Nevertheless these 4 x 120 seconds images at ISO1600 pre-processed with 5×120sec Darks have given quite a pleasing image.

I used Nebulosity 3 alone for all the image processing. This included; Background Colour Offset, plenty of Levels and Curves work to pull out the faint detail of the nebula, GREYCstoration noise reduction, and Gaussian Blur to correct some of the mottling caused by the Hue and Saturation when I tried to pull out a bit more colour.

Since taking this photo I have taken my GEQ5 mount axis drive motors off (to get at the worm gear tension adjustment screws) and adjusted the worm gears to engage properly with the big RA gear so as to remove as much backlash as possible without adding too much tension for the drive motors. I’m hoping for another good night soon to try this out and see if the aforementioned problems have been improved. Also I have learnt that a bit of weight bias is required to prevent the tip and topple affect of the mount.

NGC6888 The Crescent Nebula

If you read my previous post you’ll know that on the same night I had lost M57 behind the trees, and so NGC6888 was next on my list. In the image to the right you can only just make out a faint wisp of the brightest part of the nebula (click the image to open it full size, then hit Back when done). You would have to compare it with one of the many other successful images of The Crescent in Google Images to see how it should look.

So what went wrong?

Obvious really - bugger all exposure time. I set up to take 20 x 30 second exposures at ISO6400. Out of those only 7 were useful for stacking due to trailing caused by wind or periodic errors in the worm gear of my mount. While the 7 images will have helped reduce the amount of noise in the image (I also combined in Darks+Bias in the pre-processing), 30 seconds just wasn’t sufficient to bring out this faint nebula when post-processed in Nebulosity 3 and Photoshop. I think something more like 5 minute exposures is required reduced to ISO800, but for that I will need to use autoguiding - something I don’t have the right equipment for just yet (although I’m close). Also my EOS600D has not been modded to remove the infra-red filter, and so I’m only likely to bring out the brighter parts of the nebula anyway.

So while this image is a bit pants, well apart from the fact its quite a nice starfield, I try to take something positive from it, and hope that in due course I’ll take a much better one which does The Crescent proud, and will put this one to shame!

M57 Ring Nebula

It took me quite a while to get everything setup and familiar with my DSLR, and experimenting with the ISO settings and exposure, turning off both the Long Exposure and High ISO Noise Reduction settings in the camera, change the screen to a less intense colour scheme and brightness, then trying out Liveview in the EOS Utility, pointing at a bright star to get focused, then slewing to M57 and trying to find it, then changing from Liveview which was totally black, to longer exposures, but still no joy……

By now it was about midnight (well I also kept chatting to various people wandering by, all quite a relaxed affair really) and I still hadn’t managed to image anything….. well the night is yet young, I was planning to stay up until about 3am.

After going back into the caravan for a coffee and whisky, and a think about what I could be doing wrong, I decided to go back to basics and check everything over. Returning outside and red-light back on, I discovered that despite my dew-controller being turned on it was at a low power setting, and the front of the C6 was thick with dew, doh! So hairdryer to the rescue I got it cleared, and whacked the dew controller to maximum.

Finally and after upping the ISO to 6400, and doing a 30 second exposure I was able to make out the starfield and the nebula very faintly, but by the time I was ready to take some more shots for stacking, the darn thing had crept behind a tree! Game over for the night on M57.

So the above image is the result of just one 30 second image, processed with some stacked Darks which I created a few days later (so wrong temperature), and no Flat frames. Post-processing was done in Nebulosity, then Photoshop. Rather noisy, and could have done with being cropped, but I like it.

After opening my .CR2 RAW images, then registering and stacking them the resulting image was a tall narrow rectangle. I also noticed that the image resolution sizes shown in the image list was 1336×3516, rather than the correct size of 5184×3456.

After a bit of head scratching and Googling it turns out that the version of DSS I have (3.3.2) does not understand my Canon RAW format properly. This is because DSS decodes RAW files using the DCRAW library by Dave Coffin, and version 3.3.2 of DSS is built using an older version of DCRAW.

The fix is to download the latest version of DSS 3.3.3 (which is a Beta) from the following link:-

http://deepskystacker.free.fr/download/DeepSkyStacker333beta45.rar

This also meant I had to download WinRAR to extract the files. The RAR file contains just 3 executables, which simply overwrite the files of the same name in the Program Files folder where DSS lives.

After restarting DSS it shows it is 3.3.3, and reading the set of files in again, they now show the correct dimensions for the RAW files and the final image result occupied the full screen properly.

I really like the tutorials and explanations of astrophotography principles at the DeepSkyStacker website. They helped me understand the reasons, preparation and use of Darks, Flats, Dark-Flats and Bias/Offset images to reduce the noise in the image, and the kinds of settings I should try with the camera.

I also found this Deepskystacker astrophotography tutorial to be very helpful.

This is the second year I have been to the Kelling Star Party, and it was good to meet up with familiar faces and friends made at last years event (hi Simon, Darryl and Keith!).

This year I made more of an effort to go from one field to the other during the night time observing sessions (last time I stayed very much with my own gear, venturing only to neighbouring pitches). I thoroughly recommend taking the time to do this, as I learned a lot by chatting to fellow astronomers about their kit and asking for tips and advice. The majority of people are more than happy to talk about their passion and show what they are doing or share the view through their eyepiece. It’s one thing to drool at all that lovely kit during the daytime, but even better to see it in proper use at night! Looking through the giant dobs was amazing.

As explained in a previous post I recently got a new Canon EOS 600d DSLR and I wanted to try it out, but was a little vague on how I should set up the 600d camera for astrophotography, and what software I should use beyond that supplied with the camera (namely EOS Utility, Zoombrowser EX and Digital Photo Professional). By talking to people I learned that I should try about ISO 800 (or ISO 3200 to bring enough light for previewing in Liveview for focusing on dimmer objects), and that with my CG5 EQ mount I could probably manage between 30 seconds to 1 or 2 minute exposures, but not really much longer because my mount is not autoguided yet.

Watching a guy called Mark Shelley (www.markshelley.co.uk) operate his kit was the most interesting and instructive. He was using a lovely “banana yellow” Takahashi OTA with an Infra-Red modified Canon 350d to capture NGC6888 The Crescent Nebula, and was very helpful and patient answering my many questions about the setup and software.

He was using Stark Labs Nebulosity (for initial framing and focus preview), IRIS and/or DeepSkyStacker (to check exposures and overall look of the images after capture, and for later processing of the images), Bhatinov Grabber (this uses a cut-n-paste method to grab the star diffraction image created by a bhatinov mask from the Nebulosity image display, re-displaying the selected area in its own screen, and indicates automatically when best focus has been achieved). Although Bhatinov Grabber can control an autofocuser, Mark was actually performing the focusing manually and using Grabber simply to monitor the diffraction spikes.

Mark had developed his own shutter control and dithering software which integrates with PHD autoguiding software (the dithering deliberately moves the scope by a minute amount between images to help post-processing better distinguish what is real and what is noise in the image).

I also discovered EQAlign to help with polar alignment. Of course accurate polar alignment is crucial to good long exposure astrophotography.

So I now knew about all kinds of goodies to investigate further. Unfortunately my phone signal at Kelling was rather too poor to setup a WiFi hotspot to download the software to try it out, so for the weekend I made do with EOS Utility and the new knowledge gained to attempt capturing some images on my 600d. I’ve yet to post-process these to see how well I did !

Overall this year was very enjoyable. The weather forecast was not looking good a week before, but we were treated to some clear nights with beautiful views of the Milky Way, and two hot days during which we also visited Sherringham and Weybourne for the 1940’s Wartime Weekend, where the locals dress up in original uniforms and attire of the day, with policeman, German soldiers, RAF, Army, Naval officers, and the ladies looking excellent in their dresses, furs and hats, everything made all the more authentic by the North Norfolk Steam Railway carrying passengers between Holt and Sherringham. It really was like stepping back in time.

We had to book quickly for 2013 ! On the day we arrived, someone had already booked our pitch for next years event, so next time we will be on a different camping pitch. Also the dates are over the weekend of 5th/6th October so it will be interesting to see what difference this makes in terms of darkness, coldness and weather generally.

Hope it will be as good, and looking forward to it already!

But we are booked for a Norwegian cruise holiday early next year, and wanted a good quality camera to use on the trip and to get some shots (hopefully) of the Northern Lights aurora, so we splashed out and got the 600D. I am very pleased with it, and staggered by the features it has.

So far I have attempted some wide view shots of the night sky, with 30 second to 1 minute exposures, which give a good idea of the sensitivity of the camera, but of course result in trailing of the stars. I’ve got a small motorised EQ tripod mount which a friend lent me (cheers James), and I will be having a go with that soon.

Also I have ordered a Canon EOS (AF) compatible T-ring adapter plus a Celestron SCT T-adapter to mount the camera directly to the backplane of my C6-SGT telescope. And I will probably also order BackyardEOS to assist with focusing and taking sequences of images.

All good stuff to look forward to, particularly when we go to the September Star Party at Kelling Heath.

It has been possible to photograph the Dragon nearing approach to the space station, as shown in this picture. The two streaks across the picture are the paths of the two craft across the night sky, one bright, the other quite faint.

This historic occasion marks the first docking of a commercial space ship with the ISS.