Can anyone recommend a readily available 4x5 sheet film and/or exposure and development techniques that would be suitable for contrast masking?
Can anyone recommend a readily available 4x5 sheet film and/or exposure and development techniques that would be suitable for contrast masking?
Wayne: "Can anyone recommend a readily available 4x5 sheet film and/or exposure and development techniques that would be suitable for contrast masking?" Hi Wayne, these are the notes I made when our group made unsharp masks - I am sure there are others who can contribute as well.
We use FP4+ film in 5x7 sheets, as we can get at least a couple of medium format negs on that, or a 4x5 neg; develop the masks in Kodak HC 110 film developer.
With the room light on:
Put a framing L-shaped cardboard, to use as a guide, inside the contact frame. (Later, we will be placing the unexposed film against the in-side edges of the L-shape.) Centre the part of the contact frame which will hold your neg right under the enlarger lens.
Tape the previously developed film negative (for which you need a mask) on top of the contact glass, notches to the bottom right corner for emulsion side down, in the same position as you will be placing the unexposed film.
With the room light off:
Place a sheet of unexposed 4x5 FP4 film against the inside two edges of the L-shape, below the glass in the contact frame, notches to the bottom right corner for emulsion side up. Expose for 3 seconds at F32. Remove film and place in film box. (we do several sheets of masks at a time)
Developing the Unsharp Mask
With the room light off, transfer the film sheets from the box into the 4x5 development tank. Finish the development process with the room light on.
Pre-mix the developer: 12 ml of HC 110 developer and fill to 1600 ml with water.
Pre-mix for the 2nd wash: 1600ml of water with approx 1/3 of an eyedropper of photoflow.
Fill the stop, fix and pre-soak jugs to 1600 ml.
Using a 1600 ml 4x5 sheet film tank:
1 minute pre-soak; 3 minutes Developer, 30 seconds stop bath; 5 minutes fixer, 5 minutes 1st wash. Discard the wash water. Add the premixed 2nd wash water/photoflow mixture and soak for 1 minute. Hang to dry.
Later, on a backlit slide box, match the unsharp mask with the negative, tape them together. Others use pin registration systems.
Thank-you for your information. It definately helps me. Well, I have plenty of experimentation to do, but I'm off in the right direction.
I've used TMX with plain ID-11 but can't recall the exposure/development details - I'd have to look at my notes. In post-exposure Ctein recommended TMX and provided the details for a colour neutral developer (uses readily available chemicals) which is probably what I'll use when next I need to mask something. I believe you can download a pdf of the book from his website.
Both TMX100 and FP4+ are excellent masking films. How you do it depends completely on
what you are trying to achieve. Chome masking, color neg masking, and b&w neg masking
are all somewhat different and all depend on the specific print medium as well. Several
developers work well but my favorite is very dilute HC-110, but again, the exact DMax,
contrast, and color balance of the exposing light under the enlarger are all application
dependent. Ctein used a developer he named Muir Softshot, but has also successfully
experimented with my own developer which I tweaked for very critical dye transfer masking
and gives a straighter line clear down into the toe of the film.
Oh I should add ... if you are serious about this you'll want to acquire some sort of precision punch system and matching pin-register contact printing frame. For just learning
purposes you can simply register and tape over a light box. Ordinary 76 developer can be
used for basic experimentation, but and you might want to aim initially at with a DMax no greater than .30 and work your way from there with printing experience. If you don't have a densitometer you can just compare density visually using a graphics step tablet.
Hi Wayne,
As Drew Wiley mentinoned a dmax of 0.3 is what we aimed for. The image on the mask if very light, looks almost non-existent, but it works wonderfully when sandwiched with the neg.
That's what I figured. Lith masking film was recommended to me, but that doesn't seem to be readily available. So controlling contrast and exposure through development would be the logical(?) progression.
My use would be masking for color enlarging. I have a particular negative in mind that I think would benefit from it.
Lith film is no good for general masking. It's made for high contrast. Contrast masking is just the opposite and requries a very soft gradual scale. What lith film is used for is highlight masking, which is an advanced tool you can use once you master basic contrast masking. Take things a step at a time. Learn what a simple mask will do first. The easiest
way to diffuse the image in contact its with an intervening sheet of 3-mil or 5-mil mylar
which is frosted on both sides. You can get this at better art stores and cut in down into
film-sized sheets.
Lith film makes the best masking film as it gives a very wide range of contrast, is fine grained, and relatively inexpensive. However, due to changes in the printing industry it is getting harder to find. I have found http://www.ultrafineonline.com/ulhicoorlifi.html to be a good replacement for my previous favorite Arista Lith film. I develop it in various dilutions of Dektol.
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