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dark current noise

Started Jan 5, 2016 | Discussions thread
RedOctobyr Regular Member • Posts: 298
Re: Home-made "slim" T-Ring adapter for Micro 4/3

This may not be the right place to ask, but it seems like a place to start. I was trying some long-exposure night sky time-lapse photography the other night, with my E-M5ii, running firmware 1.3, I think.

I tried exposure times of 4 seconds to 20 seconds. I was using electronic (silent) shutter, the heart icon, to reduce the mechanical shutter wear during time-lapse. I had Noise Reduction (?) disabled, the one that turns off dark-frame subtraction.

I was surprised to see that, with even a 4-second exposure, using silent shutter, the camera apparently did a dark-frame subtraction anyhow, even though it was disabled, as far as I could tell.

When I set the shutter to anti-shock with mechanical shutter, the dark-frame subtraction didn't happen, and I could shoot again immediately after the exposure finished.

Is this how it works on other Olympus cameras, is this "normal"? Or did I just miss something?

I knew silent shutter could introduce banding, and might reduce bit depth. But I didn't realize it apparently introduced a requirement for dark-frame subtraction for multi-second exposures.

 RedOctobyr's gear list:RedOctobyr's gear list
Nikon Coolpix P7700 Olympus E-M5 II Olympus M.Zuiko Digital ED 40-150mm 1:4-5.6 Olympus 12-40mm F2.8 Pro Panasonic Lumix G 25mm F1.7 ASPH
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