I can't get exposure times greater than 1 second using the Pegasus Flat Panel 250 with the ASI294MM Pro camera, using the ASIAIR automatic feature and default gain. Have others had the same problem? Is it OK to use a zero gain to get a longer exposure? What about using sheets of ordinary white copy paper as a filter to lower the brightness of the panel?
For long exposure, you need to reduce Flat Panel light. And then, you can do an long exposure.
Your flats must be taken at the same gain and temperature of your lights.
If the auto flat exposure is too short your panel is too bright, put diffusing materials between it and the scope. If your current flats calibrate fine there is no issue.
I use ND film cut from bigger sheets you can buy from photographic equipment shops. Electronic dimmers are not enough, still too bright and other materials colorise the light and you get poor results in stacking.
