I recently imaged NGC3293 cluster in Carina using my QHY268c on a 10"F/8 GSO RC, captured the stars nicely in 2hrs30min, the data frames varied from 3min to 5min but I couldn't for the life of me process any of the background nebula into the image. Is this a matter of integration time or an inherent problem with OSC cameras capturing faint nebula. Bortle 5/6 suburban skies
