It only needs to be decreased a tiny bit to benefit.
That said, there are limits to the recoverability of highlights. It’s just not made clear since there aren’t intermediate histograms except at tone curves.
It only needs to be decreased a tiny bit to benefit.
That said, there are limits to the recoverability of highlights. It’s just not made clear since there aren’t intermediate histograms except at tone curves.
Hi @Thanatomanic ,
many thanks for your time I’ll shot the images as claimed in Rawpedia but one question
Can you direct or explain me what is raw scaling for (I googled but I didn’t find a clear explanation for men as me )?
Cheers
Gabriele
I am not very familiar with the details. The only explanation I know is here: RawTherapee/camconst.json at dev · Beep6581/RawTherapee · GitHub
Somewhere in the paragraph titled ‘How to Measure White Levels’. Hope it helps, and thanks for providing the shots!
Thanks, I didn’t read it (camconst.json) ever…but …
what does it mean if my camera ( Nikon D300) isn’t there??
How RT can decode my raw if D300 isn’t there?
Decoding a raw file is a totally different beast. The NEF format for the D300 is well-supported, so RT can decode the image data correctly. However, it needs a little more guidance to display that data properly. That’s where camconst.json
comes in.
Thanks… Than We’ll try to give more guidance for D300 decoding… When I have time ( soon) I’ll send the images
Hey,
The Nikon D300 is supported for many years. There is no need for changes for this camera.
Find attached a pp3 file with the elements that tackle your problem.
_DSC4330_1.NEF.pp3 (14.1 KB)
Here a screenshot of the result
Hi Reginald,
your PP3 solves magenta but not completely for color propagation… however good for now
Thanks
Hi @Thanatomanic,
I made some photos as here but there is something I do not understand.
When I shoot for LENR=yes I enable the option in the menu but I have no LongExposureNoiseReduction
tag in exif… I have only Noise Reduction which is OFF for ever even if I enable and disable the option… However I upload the images to Filebin | ukggmx9z2smbttw7 and I’m here for other informations.
@dafrasaga Thank you for uploading. I don’t know why the LENR didn’t work. I also don’t see any usual differences between the longer exposure shots and the short exposure shots, so I think it is safe to assume that no LENR has been applied.
Some of your lower ISO shots were not fully overexposed. I also see that the G-channels seem to be slightly non-unform, but nothing to worry about. More troubling is that after I enter the white level values obtained from my analysis, I still get a purple look in your original image. I need to look into this a bit further…
It might help if you could redo the shots at lower ISO and use an even brighter scene. In particular I would like shots of ISO 200, 250, 320 and 400. If possible, could you addtionally supply these at intermediate f-values of f/4.0 and f/2.8?
The fact that they are not in the exif should not worry you, as not all cameras write the tag in exif.
But a hint here: when the camera performs LENR, it will take 2 exposures. So if you hear your shutter go on twice that all is fine.
Also, most cameras will do LENR only if your exposure time is bigger than a specific value. So have a look in the manual to check for what values you should set.
Hi Daniel,
Yes, the exposure time have to be bigger than 8s…
Thanks for the tip
Hi @dafrasaga the additional shots were helpful, thank you! I have now also seen the ‘aperture scaling’ effect in action for the first time
I am a little stumped though, because even though I think I did my analysis right, and even with the additional samples, I still cannot get rid of the purple highlight in your original image. Somehow the whitelevels are still off…
But there are still a few tricks we can pull for which I hope you can oblige. Could you also provide the following shots:
I know I’m asking a lot, but I kinda like these analyses and it bugs me that the problem isn’t resolved yet
FWIW, this is my current change for camconst.json
if you want to try it out yourself:
{ // Quality B, samples provided by dasafraga (pixls.us), intermediate aperture scaling not available
"make_model": "Nikon D300",
"dcraw_matrix": [ 9000, -1966, -711, -7030, 14976, 2185, -2354, 2959, 7990 ], // DNG_v13 (Neutral v4)
//"dcraw_matrix": [ 9030, -1992, -716, -8465, 16302, 2256, -2689, 3217, 8068 ], // DNG_v13 (Neutral)
"ranges": {
"white": [
{ "iso": [ 200, 250, 320, 400, 500, 640, 800, 1000, 1250, 1600 ], "levels": [ 16383, 15292, 16383, 15317 ] }, // R, G1, B, G2 - R G typically saturate, G1 G2 differ slightly
{ "iso": [ 2000, 2500, 3200 ], "levels": [ 16383, 16323, 16383, 16347 ] }
],
"aperture_scaling": [
{ "aperture": 2.8, "scale_factor": 1.025 },
{ "aperture": 4.0, "scale_factor": 1.011 }
]
}
},
Maybe I am just not understanding something right, so ping @heckflosse or @jdc.
If I look at the overexposed area in the sky in the provided raw image of the boat, and set demosaicing to ‘None’, I readout R = 16383, G1 = 15340 (or slightly different), G2 = 15351 (or slightly different), B = 16383. I now set these levels as white levels in camconst.json
. If I then reload the image and set demosaicing to ‘Mono’ I get consistent values of RGB = 1. I interpret this as a confirmation that the white levels are set properly. But when I then switch to any other demosaicing method, the readout shows that the G channel is less than 100%.
I cannot understand why, so I hope someone can enlighten me
Hi @Thanatomanic thanks for your time…actually I Am busy but I will make new shot soon… Many thanks for now
Hi @Thanatomanic,
I made the shots …I used gofile because filebin got network error I hope it’s the same…
Ask me whatever you need
If I’m correct… Do I have to make a camconst.json file where I have options file ??
Would it be as
/home/gabriele/.config/RawTherapee5-dev ??
I don’t know if it’s of value but if I disable Clip out-of-gamut colors and I decrease the Exposure the magenta is more evident
To update your own camconst.json
, just edit the file in the installation folder of RawTherapee. Look for the D500 and just add the D300 entry above it. I am not sure if it would work if you create your own file… Never tried
The updated version of the camconst.json
entry looks like this:
{ // Quality B, samples provided by dasafraga (pixls.us)
"make_model": "Nikon D300",
"dcraw_matrix": [ 9000, -1966, -711, -7030, 14976, 2185, -2354, 2959, 7990 ], // DNG_v13 (Neutral v4)
//"dcraw_matrix": [ 9030, -1992, -716, -8465, 16302, 2256, -2689, 3217, 8068 ], // DNG_v13 (Neutral)
"ranges": {
"white": [
{ "iso": [ 200, 250, 320, 400, 500, 640, 800, 1000, 1250, 1600 ], "levels": [ 16383, 15292, 16383, 15317 ] }, // R, G1, B, G2 - R G typically saturate, G1 G2 differ slightly
{ "iso": [ 2000, 2500, 3200 ], "levels": [ 16383, 16323, 16383, 16347 ] }
],
"white_max": 16383,
"aperture_scaling": [ // There seems to be no aperture scaling at ISO2000+, but we cannot deal with that
{ "aperture": 2.8, "scale_factor": 1.0246 },
{ "aperture": 3.2, "scale_factor": 1.0214 },
{ "aperture": 3.5, "scale_factor": 1.0140 },
{ "aperture": 4.0, "scale_factor": 1.0106 },
{ "aperture": 4.5, "scale_factor": 1.0076 },
{ "aperture": 5.0, "scale_factor": 1.0024 }
]
}
},
I’m sorry to say that this does not solve the purple issue, and I am really out of my depth to answer the question “why?”. I expect I am missing some essential information on how these entries actually influence the processing, but currently I have no desire to dive into the code. I hope somebody else can take a look. Maybe it would be good to report this as an issue on the GitHub tracker…
To be continued, I hope.
I wonder why some camconst.json entries have only one white level, while the comment mentions different ones, for example
{ "iso": [ 100, 125, 160, 200, 250, 320, 400, 500 ], "levels": 15520 }, // typical G1,G2 15520-15800 R,B 16383
When I use the lowest WL from your entry for all channels, the purple issue goes away.