DSLR v Dedicated planetary camera - advice please.

[runoffshed]

I have recently had a go at using Backyard EOS to take the live feed off my Canon 600d with the 5x setting within the software to obtain what I have read is a close approximation to a 1:1 pixel image.  I have only tried the Moon and Jupiter so far, both in quite poor conditions, but I was quite pleased with the results. (But I am not a good/experienced imager)

My question is, how would the images I can obtain this way compare to a low end dedicated camera like the popular ZWO ASI 120mc?  Do people think it would be a worthwhile upgrade or would it be better to hold off and save for a much better dedicated planetary camera?

I have looked around the web and although I can find images obtained in both these ways it is hard to compare them as the scopes/locations/imager are always different.  Jerry Lodriguss wrote a great article in Sky and Telescope about using a DSLR for imaging planets using movie crop mode or equivalent and has produced stunning images but he is using a C11 and doesn't mention comparisons with specific cameras etc...

If anyone has any thoughts on this I would really appreciate the advice.

Many thanks

John

[PeterCPC]

I have taken images of Jupiter with my Canon 550d and also with a ZWO ASI120MC. Without any doubt you will be better off using something like the ASI120MC as it takes high frame rate images which you can stack in AS!2 and the image scale is much larger. If you use an ASI with a Barlow/Powermate you will get a better image IMO. If you look in my Gallery you can see images taken with the ASI. I have now upgraded to the ASI224MC so I am hoping for even better.

Peter

[runoffshed]

Thanks Peter, that's really helpful.  I've just had a look at your gallery...fabulous!  

I should have said in my question that I was stacking the live feed images in AS2, although the frame rate was only around 15 or 20 per second which I guess is a lot less than your ASI.  I haven't produced any Jupiter images anything like as good as yours...not remotely close...so I guess that answers my question thank you.  

(I see you have a 120ED - I was using a bog standard Vixen 102mm...a scope I have a huge affection for!).

You must post when you've got something on your new camera as I'd be interested to see the difference.

Thanks for the advice.

John

[jsmoraes]

I am not expert in photography and camera tecnologies. I think that the great difference is the size of sensor.
As astrophotography is result of projection of an image on the sensor, when the sensor is small you have the planet or Moon surface projected on full surface (or almost full surface) of the sensor. Therefore you have the target with more resolution (pixel scale), catching more details.

Below you have Jupiter by ASI120MC and Canon 1100D. The same telescope (GSO 305 mm) with the same Focal Extender 3x (kind of barlow). The result of projection of Jupiters' image on Canon sensor will have less pixels than the result of projection on ASI camera. The Canon sensor has more pixels, but as it is large ... the image will activate less pixels.

With Canon I used planetary mode from BackyardEos with 5x ressource activated.
With ASI I used Sharpcap.

Both stacked in AS!2, enhanced with wavelets filters from Registax 6 and Photoshop CS3.

[runoffshed]

Thank you JS Moraes, that's a very telling comparison - and a wonderful ASI 120MC image - and backs up exactly what Peter suggested as well.

Many thanks to both of you for your help/advice.  I'm in the market for a 120mc!

John

[Pete Presland]

I have never used a DSLR for planetary imaging, but I would think it would be no contest to be honest. 95% of imaging is done with them, which is a very good indication.