dslr vs ccd

[iantobach]

As i`m just about to buy a new dslr(it`s my birthday next month, yippee, another year older), would like opinions on ccd versus dslr`s for imaging, ie ease of use,set up time cost, and image quality.

[MartinB]

DSLR pros :-

Cheaper (CCDs expensive)

Can do much much more than astro

Large chip (equivalent sized CCD prices start at £2800)

Doesn't need a laptop (but laptop still offers advantages)

CCD

Cooled chip gives very low noise (way lower than DSLR)

Very sensitive across the spectrum (unmodified DSLRs tend to lack red sensitivity)

Have the option of binning (grouping together pixels) to increase sensitivity

Mono chips can be used with filters to give tremendous flexibility especially allowing narrow band imaging - great for light polluted sites

DSLRs can be modified to improve astro performance. With care and skill DSLRs are capable of producing stunning astro images.

[jcm]

If you download the Aug issue on this site there is a comparison between CCD's and Canon DSLR's

Makes an interesting read.

http://www.skyinsight.net/astrophoto/current.php?r=2b9f9aff6f5a69f196812def40a1e99e

John

[MartinB]

That's a great link John and the magazine looks good. I shall call in there from time to time. I thought the DSLR CCD comparison was surprisingly wobbly.

He says that setting up a DSLR is much quicker to set up than a CCD which it must be for happy, snappy imaging but by the time you get down to longer exposure stuff with guiding a laptop is essential and the camera set up time is relatively insignificant.

His other point about a colour DSLR requiring only 1/3 of the time of an LRGB CCD image showed a major gap in understanding. His findings showed that the basic chip sensitivity of the CCD was much better than a DSLR. For a normal LRGB colour image most of the time is spent gathering luminence - the CCD will gather luminence data at a much quicker rate than a DSLR. The hue and saturation data collected with the RGB is fairly quickly done by binning the colour subs which quarters capture time (an option not available to a DSLR). So a CCD should be quicker for LRGB than with a DSLR.

I thought the best bit of the article were the comparison photos, as they say, a picture tells a thousand words!

[jcm]

Yep , I thought the article was very pro DSLR. But as you said the comparison images and graphs were interesting to look at.

John

PS I will let you know about LRGB and DSLR imaging times when my ATik 16HR arrives from Bern

[MartinB]

He he. You're going to love those clean images