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Planetary imager vs. DSLR

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#1 broca

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Posted 25 May 2013 - 08:29 AM

I usually image DSO but with shorter nights and less than predictable Florida skies, I'd like to do some solar system imaging. I have a Canon T2i and in reading the specs. at full HD it has a frame rate of 30 fps and 720p HD a frame rate of 60 fps. What are the benefits of using a planetary imager over a DSLR in .MOV mode? I've used software that converts .MOV files to .avi so the subs can be stacked in RegiStax and then processed.
I'd like to see what the community captures with a DSLR in MOV mode.

#2 sfugardi

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Posted 25 May 2013 - 02:34 PM

Steve, the DSLR frame rates of 30-60 are fine for planetary imaging, although not many people seem to be using them for some reason. My old Nikon D70s doesn't even have video capture to try out, but I'd be very interested in your results. Sharing a high end family camera that can also astro image makes a lot of sense.

Regards,
Steve

#3 dugpatrick

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Posted 26 May 2013 - 10:23 AM

I use my T2i for planetary, and I'd say it works pretty well. Color is a bit blotchy, but with enough frames you can get a good image.

My examples, with T2i can 8" newt:
http://www.flickr.co...N05/6273155880/
http://www.flickr.co...N05/7102758605/

Doug

#4 broca

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Posted 26 May 2013 - 02:58 PM

Nice images Doug. I have not done much in planetary imaging and what I have done was purely out of luck. I imaged Jupiter using individual subs (~100) from a Nikon D40 a few years ago and Saturn using a Canon T1i in movie mode. I guess I was wondering what the dedicated imagers have that a DSLR does not.

#5 Jim Chung

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Posted 26 May 2013 - 06:20 PM

Steve,

You need to image your T2i for planetary imaging using only the 640x480 crop mode video mode. Using any of the HD modes is bad because the camera is downscaling from the full sensor resolution down to 1080p and causing a lot of detail loss in the process. The 640x480 crop mode is a native unaltered data from the central 640x480 cluster of pixels, plus the smaller files size of the video make them easier to handle during processing.


Here's a comparison between dedicated mono ccd and T2i, the T2i is not bad at all perhaps lacking a bit in color definition which may be a by product of not imaging closer to f/30.

Attached Files



#6 RedLionNJ

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Posted 27 May 2013 - 01:40 PM

Steve,

You need to image your T2i for planetary imaging using only the 640x480 crop mode video mode.


This is an incorrect statement. You can also capture the center of the Livewiew at 5x zoom - this also yields 1:1 (integral pixels). To do that, you need BackyardEOS or similar software.

Any use of a OSC solution (like a DSLR) is going to need substantially longer effective focal lengths to reach a similar resolution as mono imaging with a dedicated planetary cam. Plus DLSRs are inherently less sensitive than some dedicated planetary cams. So taking both of these into account, a DSLR is only going to excel when you have good transparency and GREAT seeing. A dedicated planetary cam can excel under less exacting conditions.

Grant

#7 Jim Chung

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Posted 28 May 2013 - 05:59 AM

Grant,

While you are most correct that there is another mode of accessing 1:1 pixel data, you also seem very quick to denigrate a fellow CN member, not what I would consider gentlemanly behavior. The OP is a novice so why would I add complexity to his situation when he already has a T2i with a built in video mode for recording planetary data and then tell him to purchase additional software he doesn't really need?

diplomatically yours,


Jim

#8 Castle

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Posted 31 May 2013 - 09:12 AM

I have been using my Canon T2i for planetary imaging before I bought my Flea3. Of course it is not as good as Flea3 in terms of planetary imaging, but it does the job.
I tried all scenarios and from my experience, I can say that Crop video mode for brighter objects (Moon, Jupiter, Saturn) is the best option. For dimmer objects (Uranus, Neptune and even Saturn), I was using BackyardEOS with 5x zoom mode. In Crop mode, max. exposure time is 20ms. This value is sometimes not enough. With BYE, you can increase it. You have more control over settings on BYE.

I heard that MagicLantern firmware has some new feature which you can use customize video settings like different FPS, Exposure time, etc. and you can gather raw video instead of .MOV or less compressed video. I've never tried MagicLantern firmware but if it can provide these features, It's worth to try.

And here are some photos from my DSLR:

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#9 broca

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Posted 01 June 2013 - 08:38 PM

Fantastic images Ahmet and thank you all for the replies. I used to use a DSLR to image DSO but soon found that I was getting a lot of noise from amp glow/sensor heat etc and now use a cooled mono CCD camera. My images are much cleaner now that I use a mono CCD camera and I posted this to see if planetary imaging suffered from the same sensitivity "issue". It certainly looks worthwhile to use the DSLR to grab some targets here in our own solar system.






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