T3i Modification Issues

[Likwid]

Hello, I previously modded a Rebel XS with no issues and decided to give the T3i a shot. I initially had some focus issues, which was due to the sensor not being parallel to the lens mount which I resolved already. Once that was fixed, I took a shot in the daylight and everything seemed fine, so I decided to do a test at night on the Crescent Nebula. I shoot at 800 ISO on the Rebel XS, so I tried that setting on the T3i and the shot was so noisy, it was unusable. I brought it down to 400 ISO and everything looked ok through BYEOS with 5 minute subs on my laptop and the screen brightness all the way down. I went inside to stack the 6 test exposures and only the left side of the frame stacked. When I opened an individual frame in Photoshop, it was completely unusable. There was so much noise and a weird red noisy gradient, I have no idea how this could have happened. The sensor temperature was 42C, but I didn't think it would add this much noise into the images. The only thing that changed is the internal ribbon cables were removed and reseated twice during the modification and readjusting and I am fairly certain that I did not damage anything. Could it just be a loose connector, like the ribbon cable coming from the sensor iteself? Or is it simply due the sensor being quite hot? I attached one of the test frames and it doesn't look bad on this laptop now but it looks horrible if I increase the brightness at all. Now I am even more confused. Thank you!

[michael8554]

Highest temperature I've seen on a T3i (or 600D) is 28C on ISO 800 5 minute subs, so 42C may well be a problem.

Michael

[Likwid]

Hi Michael,

I never had noticeable noise increase on my XS, so I never thought that temperature was a possible issue. I just sank when I saw that first frame because I put so much time and effort into researching and performing the mod, I thought I damaged something internally. I left my T3i inside with the AC on yesterday and took a few darks at 23C. It was like a whole new camera and the crazy red gradient of noise was gone. I guess I'll have to only use T3i on the cool nights. Thanks for the reply!

[michael8554]

Have a look online at the Martin Pyott non-invasive Peltier mod for the 600D.

Makes a big difference on hot nights.

Michael