TF-4 Question & Lith print

[Guillaume Zuili]

Hi,

Lith prints almost always bleach in the regular fix, and sometime I wish I could keep these delicate highlights I feel in the tray (without having to compensate with burning).
So...
What TF-4 does to a lith print ? Does it bleach or not, or less than acid fix ?
Did anyone try ?

Thanks.
G.

[Michael R 1974]

I think it is more complicated than pH. TF-5 apparently doesn't bleach the image and it is slightly acidic (near neutral pH). Hopefully PE will respond with some more detail.

[Guillaume Zuili]

Thanks Michael. TF4 & 5 I guess are quite different. Will try the 5.

[Michael R 1974]

Let us know how it goes. I believe PE formulated TF-5, or at least had something to do with it.

[Guillaume Zuili]

He did on both.

[Dan Henderson]

I have used TF4 and 5 on lith prints. Never really noticed that one bleached the highlights more or less than the other. As far as I know, it is a fact of life that fixer bleaches highlights. After several years lith printing I am still impressed at how a print lightens in the fixer under the safelight. So I just try to factor that into my exposure time to end up with the highlight level I want. For me, if I can just barely see a little color in the lightest portion of the fixed print, the dry down will give me just enough more.

[Photo Engineer]

Bill Troop designed TF-4, and he and I did the work on TF-5.

From reports I have, neither of these bleaches an image of any sort to any great extent. However, excessive times will cause bleaching of images. All fixers bleach silver given enough time.

PE

[Guillaume Zuili]

I have to do the same Dan but was hoping of a silver bullet :-)
Thanks PE.
I will do a test anyway to see the differences with my regular fix.
Thanks everybody.

G.