[ghonis]

Hi David,


Sorry for the delay in getting back to you. Looks like you have the situation resolved and the problem was receiving a 500D with a noise problem. When I modify Canon DSLRs, I take test dark frames before and after modifying each camera. One reason I do this is to check if the camera has a bad horizontal banding problem for long exposures before modifying the camera. Of all the 450D, 500D and 1000D cameras I have modified, none have had the banding problem, mostly reported by some owners of the 40D. The other reason is to be sure that during the modification, I have not done anything inside the camera that results in a noise problem.


The 500D cameras I have modified all have very low noise, like the 500D used for my (450/500D/1000D) noise comparison web page. I have found that the dark frames of each camera model can vary very slightly from camera to camera, but not to the degree that your comparison to Fiona's 500D is showing. Just to be sure that all settings are the same between each camera when you're doing a comparison is to use Canon's DPP to show "Info", "Shooting Information" and compare the settings of both cameras side-by-side. I've found that even the white balance setting can affect the RAW dark frames. A "Daylight" setting gives a lower noise RAW dark frame than "AWB" on some cameras for some reason.


As Humayun recommended, it is important to cover the viewfinder with the viewfinder cover (attached to the strap) when taking dark frames (and long exposure light frames).


Good thing you were able to do the side-by-side comparison to document the problem and hopefully, Canon will replace your camera under the warranty.


Anyone interested in DSLR modifications is invited to join the DSLRmodifications Yahoo group at:


http://tech.groups.yahoo.com/group/DSLRmodifications/


Gary Honis