While doing PP on some night images from a recent trip saw something I hadn't seen before. Hadn't done many really long exposures before - 3+ minutes. Have done lots of hi ISO <30 sec. stuff & assumed the E-M5 would give similar noise w/ much longer exposures - NOT! Would like to do some long exposures for foregrounds of starscapes. Beginning to wonder is that will work w/ Oly. Wonder if IBIS limits heat dissipation from the sensor. A lot has been written about the noise from the E-M1 w/ long exposure. So last night did a simple test to see what's going on w/ the E-M5. Anyone found a way around this? So here's 50% crop from 4 minutes @ ISO 1600 w/ in camera NR turned off: _A310149_ NR Off by tradesmith45, on Flickr Same w/ in camera NR On. Notice still have hot pixels but much less noise: _A310150_NR On by tradesmith45, on Flickr Turned to my stalwart NR software DXO Prime & got really disappointing results. Here's w/ in camera NR Off & Prime at its strongest setting: _A310149_NR_Off+DXO Prime100 by tradesmith45, on Flickr Then w/ in camera NR+ Prime: _A310150_NR_On+DXO Prime100 by tradesmith45, on Flickr Prime didn't accomplish much in either case.