A mask is a piece of film used to modify another piece of film. Simple enough. Masking is the process of making these masks. From the 40’s until the 90’s, masking suggested that you were doing color work; some type of assembly, or photomechanical process. Much of the literature was written with those commercial goals in mind. They taught the method of achieving reprographic standard.
The first methods of aligning, of registering the mask-set, relied upon steam and glycerin. Next step involved cut-n-butt, the optical alignment of the films. Lithographers introduced button registration in the 30’s, Technicolor introduced pinset registration.
In the 60’s the enlarger makers, Omega, Durst, etc. introduced “color separation enlargers” with pinsets. Condit( & Bregman) came on the scene after them. It seems nobody enforced the patents.
After the decline, actually the drop, of dye-transfer BW (monochrome) separation took root. Contrast reduction from the Ciba/R world was enlisted; however, much of the equipment that had been in the lab was being trashed during the early 90s.
Along came some avid believers. the market was small enough that the workshop world could become a market for a small scale business.
Contrast Reduction Masking —
LINKS
— Lynn Radeka https://www.radekaphotography.com/
https://www.freestylephoto.com/contrast-masking-the-traditional-print
— Alistair Ingliss (gone. ) this link is to the archived site:
An article https://www.largeformatphotography.info/unsharp/ The author used the Ingliss system.
— Wainwright overview: https://www.paulwainwrightphotography.com/biblio_files/unsharp_masking.pdf
— Another, this from a Ciba user: https://www.stanstudio.com/the-unsharp-mask-analog-photoshop/
— The useful Wiki page: https://en.wikipedia.org/wiki/Unsharp_masking#:~:text=Unsharp%20masking%20(USM)%20is%20an,mask%20of%20the%20original%20image.
EZ Note:
- You can expose with either clear glass, a diffusing glass, or both. You can even put a thin glass between the two pieces of film to further decrease sharpness.
- A good masking film has no AH layer or a minimum AH layer, and has a good quantity of acutance dyes in the emulsion itself. Pan Masking film was made just for this purpose and could be exposed either through the base or emulsion side.
- Both highlight and contrast masks are similar, they just address a different part of the tone scale, if I read what you are saying right. And you can make one either sharp or unsharp depending on what you are trying to achieve. You can even combine several results into one mask, or you can use several masks together in registration. Lith masks are also nice to try, giving quite nice special effects.
- In color, you can make separation masks for color correction that can also be unsharp if desired. They can also reduce contrast. Therefore, by this method a transparency can be printed on Ilfochrome and yield results equal to the best color negatives with the proviso that you always lose some tone scale in pos-pos printing due to the two toes and two shoulders of the materials you are dealing with.
- Just make sure you keep everything in register with each other, so you don’t get really odd results.
- BTW, a nice unsharp mask can be achieved by developing in Dektol 1:3 for 3 mins or by inspection to get a just visible image. Underexpose and develop for up to 3 mins (just about the right time for that developer) and you will have a very nice B&W unsharp mask.
- Ron Mowrey
You must be logged in to post a comment.