Ryan Earl

Another thing I've noticed is that the colors shifting in DNG has to do with the Color Mode "OFF" setting. The images I attached earlier were done with the Color Mode set to "Standard" as viewing lut. It might have been stated earlier in the thread, these modes do not affect the CDNG development in Resolve, so not matter what setting you get the same CDNG. Though when setting the Color Mode to "OFF" you get a slightly shifted primary that corresponds to the same raw output in the 4K DCI BRAW. So if you're only ever shooting DNG it seems best to try both and see what you prefer.

I should clarify that I was wondering if they were shifting to become more accurate or less accurate on the Sigma FP. I think the Sigma FP's color relationships are more accurate (even more so than the URSA 4.6K) viewing the files without further adjustments inside the Linear to RED to REC709 transform I described above vs other decodes and transforms.

I've been experimenting with the Sigma FP as a quasi mini replacement for an 1st generation URSA Mini 4.6K shooting DNG. My URSA has been declining in health with buttons not responding and the screen failing after 6 years. With the URSA Mini 4.6K I have an ingrained workflow with it's Gen 3 color science and the BMD Color Space and BMD Gamma. The primary colors are accurate or at least what I've come to rely on. Then with Sigma FP I transform the DNGs via the CST tool in Resolve from 'P3 D60' and 'Linear' to 'RedWideGamutRGB' and 'RED Log3G10' then transforming to REC709. This gives me the feel of the Lift - Gamma - Gain tools that I like to use to render the color, contrast and saturation. Just in a few available light table top tests I was surprised at how well both files matched in color rendition. I had seen some tests where the reds had shifted too orange on the Sigma FP (especially recording in BRAW and ProRes RAW) with identical ISO, white balance settings. They do shift in my example but neither is perfect out of the box. I attached two log like files below. Sigma FP ISO 800 WB 5194 TINT 13.79 URSA Mini 4.6K ISO 800 WB 5194 TINT 13.79

I've owned the Nikkor 20mm 2.8 AIS along with the AIS versions of the 28mm 2.8, 35mm 2.8, 50mm 2.8, 55mm 2.8 micro, 85mm 1.8 and Nikon 135mm 2.8. They are all of the same period and some are still sold new. I think they are generally 7 bladed diaphragms with 52mm front diameters, except for the 20mm which has a 62mm. They all match really well color wise / neutral - warmish and are very sharp. Probably not any sharper than the AI versions but sharper as you go to the 135mm. Distortion is well controlled on all mentioned lenses too. I think maybe only vintage feeling in that they flare and lose contrast wide open towards the sun, they look good doing so. I used them on a Blackmagic Production camera 4k several years ago and now they mostly live on my Nikon F6 for black and white stills.