This is not necessarily a DXO issue but something I don’t understand. All my long-exposure shots (20-30sec) are showing coloured pixels when viewing at 100%. When I zooming-in the pixels disappear. When zooming back to 100% they show again. They don’t show when exporting to Jpeg. So what is the ca…

It is likely they are hot pixels. Did you see this recent thread? [image] Random colored dot with Zoom factor under 75% on Canon RAW at 3200 ISO Windows topics Hello all, Last week I’ve shooted milky way with my Canon 5D Mark3. I’ve made some tests between 1600 ISO and …

Thanks I haven’t seen the recent thread as it didn’t match my search terms. The thing is that these dots show without any corrections and with a 100 or less ISO.

Yes, I understand your situation is a bit different, but I’m still leaning towards them being hot pixels. Mark

There’s a utility to test for dead and/or hot pixels. Dead pixels are just dead, hot pixels show up with longer exposure and/or higher iso. http://web.archive.org/web/20141025175607/http://www.starzen.com/imaging/deadpixeltest.htm George

Thanks. It’s from 2001 and for Windows only. I sent this issue to Canon as well and see what they have to say. Cheers

It’s an old one,yes. That doesn’t mean it’s not working. And it’s a window program. But also a standalone program. Just run it from a usb stick on any windows pc. George

You can do this without the program too. Just take a shot with cap on and save the file as tiff if possible. Then view it on 100%. The idea is that hot or dead pixels do show a higher value then black 0,0,0. George

[image] George: You can do this without the program too. Just take a shot with cap on and save the file as tiff if possible. Then view it on 100%. The idea is that hot or dead pixels do show a higher value then black 0,0,0. …not sure about that. Noise will make values go beyond zero too…

It’s a matter of interpretation. A black image taken with cap on the lens should show 0,0,0 all over the image. Dead pixel will show a high value, noise between that and 0. Dead pixels are a hardware problem and must be seen all the time on the same place. Noise is depended on the camera settings, …

They’re hot pixels. Most camera sensors show them at long exposures because this generates heat which reduces performance. Some cameras have them at short exposures, too, right out of the box - which can mean that the camera wasn’t calibrated before being sold or that the sensor has a defect. (I’ve …

Coloured pixels showing on long exposure photos

DxO PhotoLab macOS topics

mwsilvers (Mark - New Jersey, USA, Win10, RTX 4060, PL9, FP8, VP5, Nikon Zf ) September 1, 2020, 4:27am 2

It is likely they are hot pixels. Did you see this recent thread?

Mark.