Dark frame test comparison needed – how many hot pixels do you see at 6s/ISO 3200? (OM System / MFT sensors)
Hi everyone,
I recently had a hot pixel issue on my OM-5 Mark II that got confirmed and resolved by my dealer (sensor showed a fixed red pixel visible even at fairly normal exposure settings, like 1/250s). I got a replacement camera, and while it's much better, I'm now seeing several (7 so far) faint hot pixels during a more extreme dark frame test — but only at long exposure + high ISO, not at normal shutter speeds.
I'd like to figure out if this is just normal sensor behavior or still on the high side, so I'd really appreciate it if some of you could run the same quick test and share your results (any MFT/OM System body welcome, even other brands for comparison).
Test setup:
- Lens cap ON (completely dark, no light hitting the sensor)
- Manual focus (doesn't matter, no light anyway)
- ISO 3200
- Shutter speed: 6 seconds
- RAW format
- Important: please disable "Long Exposure Noise Reduction" in your camera menu before shooting — otherwise the camera automatically subtracts a dark frame internally and hot pixels won't show up, which would defeat the purpose of this test
- Let the camera sit for a minute or two beforehand so the sensor isn't warm from previous shooting ("cold" camera)
What I'd love to know:
- How many distinct bright/colored pixels do you see when zooming into the RAW file at 100%+ (I use DxO PhotoLab, but any RAW viewer works)?
- Which camera model / sensor do you have?
- Roughly how old is the camera / how many shutter actuations?
This would really help me understand whether what I'm seeing is within normal range or worth pursuing further with my dealer. Thanks a lot in advance!