Attempt #2 at imaging Jupiter!

[Nadine2704]

Attempt number 2 at processing Jupiter.  Finding it incredibly frustrating trying to image with my current set up, so have invested in 'Making Every Photon Count' to help me decide what I should upgrade to!

Composite image of Jupiter and 3 of its Galilean moons

Canon 70d, 8" Dobsonian (prime focus and manually tracked)

1 x 30 sec video, stacked, for Jupiter

I attempted eyepiece projection, but couldn't achieve focus... no doubt I am doing something wrong, but couldn't work out what!

[michael.h.f.wilkinson]

Very nice shot, especially for a DSLR shot from a Dobsonian. Cloud belts and moons showing up nicely, and you have the GRS in there. Making Every Photon Count is an excellent source, although it does focus mostly on DSO imaging rather than planets. The two require very different equipment. EP projection can be a pain, I prefer working with Barlow or tele-centric lenses like PowerMates. Camera-wise you are better off with true planetary cameras like the ZWO ASI120MC or preferably the faster ASI120MC-S. You can find these second-hand because people are switching to the somewhat better ASI224MC (I did). This will give you more frames between nudges, although the big chip of a DSLR is your friend in terms of keeping things on chip. A tracking mount might actually be more important. For planetary, it need not be nearly as beefy as for DSO imaging.

[Pete Presland]

Excellent capture. As Michael has so well explained, a dedicated webcam is certainly the route to take.

[Nadine2704]

2 minutes ago, michael.h.f.wilkinson said:

Very nice shot, especially for a DSLR shot from a Dobsonian. Cloud belts and moons showing up nicely, and you have the GRS in there. Making Every Photon Count is an excellent source, although it does focus mostly on DSO imaging rather than planets. The two require very different equipment. EP projection can be a pain, I prefer working with Barlow or tele-centric lenses like PowerMates. Camera-wise you are better off with true planetary cameras like the ZWO ASI120MC or preferably the faster ASI120MC-S. You can find these second-hand because people are switching to the somewhat better ASI224MC (I did). This will give you more frames between nudges, although the big chip of a DSLR is your friend in terms of keeping things on chip. A tracking mount might actually be more important. For planetary, it need not be nearly as beefy as for DSO imaging.

Thank you!  I currently only attempt planetary due to my current set up, but it's actually DSO imaging that I'm more interested in, so I'm quite glad it focuses more on that!  Thank you for the advice - will also look into the ZWO ASI120MC and ASI120MC-S!

[Tommohawk]

EP projection is tricky. Better to use Barlow/Televue Powermate with video crop mode. If you do video not in crop mode you will get huge losses in compression. Also I wonder how are you stacking?

[Nadine2704]

2 minutes ago, Tommohawk said:

EP projection is tricky. Better to use Barlow with video crop mode. If you do video not in crop mode you will get huge losses in compression. Also I wonder how are you stacking?

For some reason I assumed EP projection would be simple!  How naive of me!  I stack using Registax, but I frequently see other stacking programs being recommended over Registax, so might give something else a try.

[Tommohawk]

I normally use PIPP to convert to AVI, then Autostakkert2, then Registax for wavelets only. But your main issue I think will be with video lossy compression if you don't use crop mode. That said, crop mode will make manual tracking more of a challenge.

BTW its still a really good pic and a great starting point - heaps better than my first efforts!

[Nadine2704]

16 minutes ago, Tommohawk said:

I normally use PIPP to convert to AVI, then Autostakkert2, then Registax for wavelets only. But your main issue I think will be with video lossy compression if you don't use crop mode. That said, crop mode will make manual tracking more of a challenge.

Forgive my ignorance - I'm technologically challenged - but is crop mode essentially the same as using the digital zoom?  If so, that is what I did to get this image - it did make the manual tracking a bit of a nightmare, but it provided me with better images in the end.  I did also use PIPP to stabilise the video and discard some of the poorer frames.  This is the resulting image, which I then resized for the final picture.  Not sure if that's technically how it 'should' be done, but for someone with very limited photography and computing skills, I just had to fiddle around with things until it produced an image that remotely resembled a planet haha!

And thank you!

  

[Knighty2112]

Excellent image of Jupiter and its moons. Well done!  

[michael.h.f.wilkinson]

23 minutes ago, Nadine2704 said:

For some reason I assumed EP projection would be simple!  How naive of me!  I stack using Registax, but I frequently see other stacking programs being recommended over Registax, so might give something else a try.

Nothing naive about it. AutoStakkert! 2.0 (AS!2) is better than Registax at stacking I feel. I do do my post-processing with wavelets in Registax. Just messing around with wavelet settings is the way I found my preferred settings. The exact settings differ per camera, so my settings for an ASI224MC (which are quite similar to those I used for my ASI120MC, not too odd given same pixel size), will not be suitable for a DSLR.

 

[michael.h.f.wilkinson]

36 minutes ago, Nadine2704 said:

Thank you!  I currently only attempt planetary due to my current set up, but it's actually DSO imaging that I'm more interested in, so I'm quite glad it focuses more on that!  Thank you for the advice - will also look into the ZWO ASI120MC and ASI120MC-S!

 

For DSO imaging, a basic set-up recommended most often would be the HEQ5 mount with a SW 80 ED or similar short apochromatic refractor. The mount could actually carry an 8" Newtonian OTA for planetary if the fancy takes you. An 80ED isn't nearly as good on planetary as an 8" Newtonian (I use my 8" SCT for planetary, but my few recent DSO attempts have been with the APM 80mm F/6), so I would certainly keep the Newtonian

[Tommohawk]

2 hours ago, Nadine2704 said:

Forgive my ignorance - I'm technologically challenged - but is crop mode essentially the same as using the digital zoom?  If so, that is what I did to get this image - it did make the manual tracking a bit of a nightmare, but it provided me with better images in the end.  I did also use PIPP to stabilise the video and discard some of the poorer frames.  This is the resulting image, which I then resized for the final picture.  Not sure if that's technically how it 'should' be done, but for someone with very limited photography and computing skills, I just had to fiddle around with things until it produced an image that remotely resembled a planet haha!

And thank you!

 

Sounds like you've got it pretty much nailed -  your photography and computing skills are much better than you think!

Also, I might have misled you re the crop mode thing. When in movie mode, the camera has to store multiple images very quickly. To speed this up and minimise storage space the processor compresses the images, which inevitably degrades the image especially if you process it further subsequently.

Some EOS models have a movie crop function - this then only uses the central 640 x 480 pixels of the sensor and records without any compression. Its a small field of view of course, but for planetary you don't need a wide field. I was under the impression that the 70D had this function, but it seems not - see here.

In any event, the images you have are very good, so the compression doesn't seem too detrimental. BTW I usually use 2 or 2.5 minute clips. that might give a slight improvement.

If you're serious about planetary a CCC camera is probably the way to go as you say. You will find a driven mount helpful especially as the sensors are much smaller then the DSLR. If you want to do DSOs, you will definitely need a driven mount + guiding option - the DSLR will take excellent DSO pics, bit imaging takes longer as it isn't so sensitive as a CCD. Unfortunately the best planetary CCD has different characteristics to the best DSO CCD.

Whatever you do, have fun!