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Old 16-09-2010, 03:20 PM
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DSLR vs CCD

People often raise questions about the comparison between a CCD camera and a DSLR. The thumbnail below gives a direct comparison. Both images were taken with the same scope. To be fair, I should state that the DSLR was 60min exposure, while the CCD was 100 min, but this is really only going to affect noise levels and won't make much difference to the overall impression.

PS: You have to work out for yourself which is the CCD image and which is the DSLR image.
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Old 16-09-2010, 03:42 PM
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I'd be inclined to say the image on the right is DSLR.

Reasons:

1. the nearly blown core;
2. the noise in the background;
3. saturation of stars

Mind you, a poorly processed CCD image could turn out the same.

H
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Old 16-09-2010, 04:22 PM
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1st is ccd, the second a dslr, a non modded one at that.

The well depth in a ccd gives a better chance at capturing star color, plus if it's a mono camera then all sorts of tricks can be easier applied for color details.

I do tend to think the second image could have been processed better, the first looks look a greater effort has been made. Perhaps the dslr image is an old one from the past and your processing skills have upgraded as well.
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Old 16-09-2010, 05:25 PM
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Quote:
Originally Posted by Alchemy View Post

I do tend to think the second image could have been processed better, the first looks look a greater effort has been made. Perhaps the dslr image is an old one from the past and your processing skills have upgraded as well.
Yes it is one from the vault.
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Old 16-09-2010, 08:00 PM
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The thing I love about my cooled CCD is the very low chromatic noise levels in the darker background - something you can't get a feel for zoomed out this far. Nice comparison though.
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Old 16-09-2010, 10:05 PM
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You argue a very compelling case for the CCD Geoff!


ps...Damn you!!
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Old 19-09-2010, 08:22 PM
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So what sort of DSLR and which CCD was used in this comparison?

Cheers,

Dave.
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Old 20-09-2010, 06:34 AM
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Thanks for the comparison Geoff.
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Old 21-09-2010, 09:22 AM
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A modified DSLR can produce similar images to a OSC CCD, where CCD gains is lack of noise and improved SNR, especially in warmer months due to internal cooling of the chip.
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Old 21-09-2010, 02:27 PM
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Quote:
Originally Posted by davewaldo View Post
So what sort of DSLR and which CCD was used in this comparison?

Cheers,

Dave.
Canon 350D, QSI540wsg
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Old 21-09-2010, 10:11 PM
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Interesting comparison but the one on the left (presumably the DSLR is that right?) is badly out of focus as well which exaggerates the difference more.

There's no doubt that DSLRs done right can put up a really good image. Although I personally feel that when someone gets good results with a DSLR they get into a comfort zone with it and become reluctant to take the next step and the resulting new learning curve (as well as expense).

Greg.
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Old 22-09-2010, 01:53 PM
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The main point of difference I wanted to bring out was the increased red sensitivity of the CCD. In some ways this is good, because it gives a truer rendition of the actual colour of these objects if our eyes were sensitive enough to see colour at such low light intensity. However, the red does swamp the more subtle colours, which the DSLR brings out. I suppose the way to go is narrowband filters, so you can see what the thing looks like at a particular wavelength.
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