Looking through camconst.json I noticed that the configuration for the GX9 is considered incomplete, lacking a black frame and whites for the different isos
Here they are, particularly as I think there is a magenta cast (small - not as egregious as the G90 was) which “normal” fiddling doesn’'t quite correct. These, if I’ve followed the instructions properly should help verify or modify the present configuration
If they aren’t right TELL me and I’ll do them again!
Hi @OldNick, thanks for doing this. Unfortunately, all your white frames are not pure white. Not sure why, perhaps your light source was not uniform or you needed a slightly longer exposure or lower aperture?
I did wonder… I read in the instructions not to over overexpose, so I was looking at the screen and the histogram of the camera and taking them when I couldn’t see any colour on the screen - blue sky - it was f8, but it looks as though there’s vignetting. I’ll use a different lens and do them again when we’ve got sun… Ah, also I was side on to the sun…
Shouldn’t be any problem with the black one though…
Not having the frames completely overexposed makes analysis harder. I think you may have misread the instructions, because overexposure is precisely what is necessary.
Thank you if you want to redo them
I’d imagine a dull day would do too… you could set the camera to manual, and set a shutter speed of something like a 10 sec exposure. That should blow out to solid white even if you’re pointing at a cloudy sky
I may have missed something though…
This is only allowable if you can ensure your camera does not enable some long exposure noise reduction. I believe some camera’s even do this without giving the user an option to turn it off.
The white frames are used to determine a reasonable value for a purely white pixel. For me it helps to have the entire frame to work with to get an idea of any variation there may be (which occurs for high ISO) and to determine a reasonable cutoff.
The Panasonic does allow turning it off (if you go digging), but I suspect they may have automatic NR for high isos, whether you want it or not, but I suppose if it’s consistent it doesn’t matter for profiling purposes.
I’ve managed to get a new batch done - I’m only uploading the one, for approval, if it works I’ll do the rest which should be alright because I followed the same method for all of them.
I opened one or two in RT and they didn’t seem to have any unfortunate shadows or anything.
I just hope I’m not embarassing myself again!
