![Quick clear collodion recipe](https://kumkoniak.com/103.jpg)
In the book "The Theory of the Photographic process, 4th Ed" by TH James, 1977, there is a section on measurement of spectral sensitivity of black and white materials. I can make the plots in whatever thicknesses you can think of. I have UG2A here in 0.7mm, 1mm, and 2mm versions, and UG5 and/or U-330 available here in 1mm, 1.5mm, and 2mm thick versions.Ģmm is the basic thickness of most filters, a starting point, kind of, so that is why I used 2mm in my graphs. I am not sure what thicknesses Ulf has in mind.
![quick clear collodion recipe quick clear collodion recipe](https://1.bp.blogspot.com/-MEqKDq9j_vw/XW9tmbSGixI/AAAAAAAA3Kg/g0Poc5AGJrsCqLpAUfDyYvBpRr6WYNp1ACLcBGAs/s1600/slime-halloween-recipe.jpg)
:-) I don't have any experience with Collodion Emulation myself, and I don't know what the transmission is, I just used the standard and most usual thicknesses in my graphs. Tomorrow I try to do a practical test, but I doubt that the comparison with Sony A7 is useful. Today I have prepared some collodion with Rhen formula with lithium (sometimes I use the New Guy recipe with Cadmium :-))) with flash light and that of the tanning lamp. Today I tried all the old filters I had at home with the standard Nikon Z5 and the Sony A7 full spectrum. I hope the BG39 - ø52mm that I ordered from AliExpress from Tangsinuo Store arrives soon.
![quick clear collodion recipe quick clear collodion recipe](https://theherbeevore.com/wp-content/uploads/2022/10/wp-16660388622404249974521694826458-922x1536.jpg)
your second graph (BG25 + BG39) is much clearer than mine which I created with photoshop.
![Quick clear collodion recipe](https://kumkoniak.com/103.jpg)