- Joined
- May 26, 2018
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- 366
so I have been busy (taking pictures...) and will read through the rest of the thread later...
For now quickly:
i found many threads dating back to late 90's across different sites and blogs but here on Photrio few current and short.
It is not about developing reversal film in C41, this produces negatives with switched colours. I searched Photrio with combined keywords "BW C41 reversal/slides/transparencies" and found no extensive thread.
the process similar to the older pre E4-E6 process, with manual fogging after the 1st developer, from E-4 fogging became chemical.
After the 1st BW developer and re-exposure the film looks like this (front/back) :
then development in C41.
certainly, the images i posted in OC are very bad, but then what images in what aspect relatively to what?
as i mentioned in OC, the images needed more or less tweaking ie. processing. I did a quick mod in a graphic editor and the images posted were not optimal/final, excepted the last one, almost.
one of the image did show how the film does look like after development. A closer shot (taken on a light box with a given light temperature, with a mobile phone, so already "renderings") of a frame:
now, transparencies are for projection. Projector lamps have some temperature, which has an effect on the projected coulours ....For online use and print the transparency must be scanned.
I use for MF an Epson V700, set at 2400dpi (the max real optical resolution is measured between 2100 and 2300) and Vuescan because it has the option to capture into a TIF or DNG container the raw scanned data with a choice of colourspaces. I use Kodak standart ProPhoto RGB because its wide gamut captures all possible spectrum visible to human eye. But then the raw data must be rendered in a practical colorspace, ie. sRGB.
film ----> scanner ---> raw file ---> processing ---> digital or print image
trying to evaluate how well this alternate development works, relatively to colour rendition, colour and tonal ranges, dynamic range, sharpness, I may have to deal with degradations in the processing steps.
anyway, let's take the case of this film frame with the old kolonia-melk-delikatesser shop. Here is the raw file of the V700 scan:
https://disk.yandex.com/d/YUTIWvDnS2-swA
loaded into a graphical editor it looks like this:
I have to processs that.
the obvious is to auto-level the channels and set the gamma to 2.2 (sRGB), but there's almost always a blue cast. Here to the right further adjustements bring the actual colors of the tiles, walls, brick, street lamp, foliage back the house, keeps the strong sunlight reflection on the wall, but gives a cooler sky.
The image to the right is not the best possible, but bad? no.
the only way to know how bad this is because the development itself is to shoot two films of identical scenes, develop one in a E6 kit the other with BW+C41, and the same when comparison different BW+C41 developments...
I read about Rodianal, Diafine, Xtol and older disappeared brands of BW. Fine developer are supposed to be better, so to not develop grain before the C41 dev. Diafine, Xtol clones, possibly some of the HC-110 dilution.
if reserval film is used often then E-6 kits are the best i guess, but for occasional rolls if there's some standard BW+C41 process getting close, then it would be very convenient.
what is missing is documentations summarizing the possibilities, some kind of standardization...
That was the point with my thread: hear a about recent practices ...
as for better renderings, closer to reality, of the images in OC:
For now quickly:
i found many threads dating back to late 90's across different sites and blogs but here on Photrio few current and short.
It is not about developing reversal film in C41, this produces negatives with switched colours. I searched Photrio with combined keywords "BW C41 reversal/slides/transparencies" and found no extensive thread.
the process similar to the older pre E4-E6 process, with manual fogging after the 1st developer, from E-4 fogging became chemical.
After the 1st BW developer and re-exposure the film looks like this (front/back) :
then development in C41.
certainly, the images i posted in OC are very bad, but then what images in what aspect relatively to what?
as i mentioned in OC, the images needed more or less tweaking ie. processing. I did a quick mod in a graphic editor and the images posted were not optimal/final, excepted the last one, almost.
one of the image did show how the film does look like after development. A closer shot (taken on a light box with a given light temperature, with a mobile phone, so already "renderings") of a frame:
now, transparencies are for projection. Projector lamps have some temperature, which has an effect on the projected coulours ....For online use and print the transparency must be scanned.
I use for MF an Epson V700, set at 2400dpi (the max real optical resolution is measured between 2100 and 2300) and Vuescan because it has the option to capture into a TIF or DNG container the raw scanned data with a choice of colourspaces. I use Kodak standart ProPhoto RGB because its wide gamut captures all possible spectrum visible to human eye. But then the raw data must be rendered in a practical colorspace, ie. sRGB.
film ----> scanner ---> raw file ---> processing ---> digital or print image
trying to evaluate how well this alternate development works, relatively to colour rendition, colour and tonal ranges, dynamic range, sharpness, I may have to deal with degradations in the processing steps.
anyway, let's take the case of this film frame with the old kolonia-melk-delikatesser shop. Here is the raw file of the V700 scan:
https://disk.yandex.com/d/YUTIWvDnS2-swA
loaded into a graphical editor it looks like this:
I have to processs that.
the obvious is to auto-level the channels and set the gamma to 2.2 (sRGB), but there's almost always a blue cast. Here to the right further adjustements bring the actual colors of the tiles, walls, brick, street lamp, foliage back the house, keeps the strong sunlight reflection on the wall, but gives a cooler sky.
The image to the right is not the best possible, but bad? no.
the only way to know how bad this is because the development itself is to shoot two films of identical scenes, develop one in a E6 kit the other with BW+C41, and the same when comparison different BW+C41 developments...
I read about Rodianal, Diafine, Xtol and older disappeared brands of BW. Fine developer are supposed to be better, so to not develop grain before the C41 dev. Diafine, Xtol clones, possibly some of the HC-110 dilution.
if reserval film is used often then E-6 kits are the best i guess, but for occasional rolls if there's some standard BW+C41 process getting close, then it would be very convenient.
what is missing is documentations summarizing the possibilities, some kind of standardization...
That was the point with my thread: hear a about recent practices ...
as for better renderings, closer to reality, of the images in OC: