Is there shutter life limitation for QHY9's shutter?
No. Unlike DSLR's shutter. QHY9's shutter has no life limitation. It will never wear and never tear. You can use it as long as possible.
About QHY9 FineTune
My QHY9's hot pixel much heavy than expected.
If your QHY9's hot pixel is much more than expected. It maybe the problem of DC201. Need to replace one.
If you want to verify this issue. This image is take under -20C. Exposure time is 300sec. Gain=0. Please take a picture use the same setting and compare with this one.
If you want to confirm this issue. You need to messure the -15V output of DC201. You can take a 10sec exposure. If the -15V drop during the exposure. This DC201 has such issue. Please contact dealer to replace one.