DSLRUsers.com

This is quite an interesting comparison:

http://wyofoto.com/40D_Image%20quality/ ... otout.html

looks like the 40D competes very well in the lower ISO bracket vs the 5D - 100-800 iso.

Adobe has yet to support the 40D in camera raw.

Jonathan

Quiter interesting, and yet the 40D has a smaller sensor than the 30D. I guess one would have to see the real pictures because the reductions would have taken their toll on the images.

don't forget that it's the digic iii processor on the 40d compared to digic ii on the 5d and 30d. There must have been improvements made to the processing algorithms as well.

Good post on OCAU about this very thing..

http://forums.overclockers.com.au/showt ... 944&page=3

Reply here:

A camera with a 5.9x5.9 micron sensor (40D) can never hope to compete with a camera with a 8.2x8.2 micron sensor (5D) as far as signal to noise or dynamic range is concerned. This assumes all else is being equal. Sensor temperature is critical and it is easy to fudge comparisons by not making sure both sensors are at exactly the same temperature.
The signal to noise or dynamic range of a sensor is directly proportional to pixel area. The 5D has a measured dynamic range of 14.3 stops of its sensor. What this means is that because of the limits of the A to D converter being 12 bits the 5D still has maximum dynamic range even at an ISO of 500. For a 20D this is at between 100 or 200 ISO.

For more info see here.
http://www.clarkvision.com/imagedeta...ary/index.html

Yes I am biased as I have a 5DH that I use for astrophotography.

Here is an image 2.4MB of the Large Magellanic Cloud.
http://members.optusnet.com.au/~fmlee/LMC_100ED_N.jpg

Image Details
Canon 5DH, modded 100ED at 686mm f/6.8, EQ6 mount
5x8min at 1600ISO with Astronomik HA filter
6x8min at 500ISO and 6x8min at 1600ISO with Hutech Nebula filter
Used ImagesPlus to stack each set of images
Merged the nebula filter data with EasyHDR and then added the HA data with ImagesPlus. A bit of levels in PS.

They are comparing a camera thats 2 years old to a new one. The comparison is best with Nikons equiv model. I'd take a 5D over a 40D any single day of the week. FULL FRAME

thanks kris- what you say makes sense, just not sure if there will be a "notoceable difference".

the overclockers link doesnt let me see the discussion- it may be a members only thing??

also the clarkvision link for me doesnt work, but clarkvision home is a great site- thanks
Robert