t-grain shine

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i've recently been testing some tmx 100 and delta 100 for the first time since i've been seriously into darkroom work, i have to say i'm quite amazed by the acutance with rodinal, i didn't think my enlarger lens was capable of such resolving! positives aside, i'm wondering why almost all the portrait shots have shiny glaring skin areas on the prints, this "feature" does not seem to occur with my plus-x shots in identical lighting, is it some kind of spectral sensitivity these t-grain films have? anyone else notice this and find a way to cut the shine back some(powdering the face is not an option here)? thanks for any tips & i'll post if i figure out something that helps

joe

-- Joe Holcombe (joe1013_@excite.com), September 24, 2001

Answers

I'm guessing here, but it could be that the lack of a shoulder (seemingly endless straight-line section of curve) on these films lets the highlight contrast "go to far" (a common problem with these films). Older technology films, like Plus-X, have a limit (shoulder) that may preclude this problem.

I'm not a fan of the new films, and prefer to work with the older ones. Maybe somebody with more TMax experience can offer a suggestion.

TMax 100 & 400 have slightly reduced blue sensitivity (compared with traditional films) which might play a role here, depending upon the color content of your light.

-- Charlie Strack (charlie_strack@sti.com), September 25, 2001.


I suspect Charlie is right on both counts: reduced blue sensitivity equates to increased red sensitivity, so pink flesh would show increased density, plus the lack of a shoulder. I don't use T-Max 100 much, but I often use T-Max 400 and I always reserve it for situations where I want to increase contrast. If I use it on a sunny day, the negatives will be difficult to print, even if developed in PMK, which normally allows you to print detail in the high values much more readily. Rodinal has a tendency to overdo highlights with any film, but particularly T-Max films, so you have to carefully adjust dilution and time, as well as exposure index.

-- Ed Buffaloe (edb@unblinkingeye.com), September 25, 2001.

Joe, Just to clarify what Ed has said, you need to reduce your development time. Try a 20% reduction in time and adjust from there. Keep agitation to moderate levels (about 5 seconds per minute). If you are not already doing so, I would use a dilution of at least 1:50 with ISO 100 (or below) films. Higher dilutions up to 1:100 may also be used.

-- Michael Feldman (mfeldman@qwest.net), September 25, 2001.

I agree with Michael. I use regularily Delta 100 in Rodinal 1:50 and get negatives far easier to print when I reduce the development time by 20 to 30 %.

-- Xavier Colmant (xcolmant@powerir.com), September 26, 2001.

If you use TMX at the specified EI of 100 and the required development time to get the film to respond at EI:100, you are actually 'pushing' the film by 2/3 stop (its true EI is 64.) The additional development to get '100' will over develop the highlights. Why are you using TMX? Delta 100 has an honest EI:100, and with PMK (14M @68), has excellent highlights. If you liked +X, try FP4+, a much better film with a real EI of 80. PMK for 13M @68.

-- Michael Fraser (mdfraser@earthlink.net), September 29, 2001.


Thanks guys, the straight shoulder makes sense, i've now shot a roll of tmax 100 @ 50 and developed according to ed's 1:75 recommendation and it makes better prints in regards to the shine (except for some flash shots but i need to practice more at 50 iso with my flash as this was my first try)..... one thing i noticed however is that these negs are quite thin with very short exposure times for my enlarger, i'm normally printing 30 secs @ f/8 but these are 10 sec @ f/8.... is this normal for this film? i like the results and the enlargability of this combo but the thin negs were a bit of a surprise...

thanks again joe

-- Joe Holcombe (joe1013_@excite.com), October 01, 2001.


If the negs are thin, but printable, you may still need to make some adjustments. Try increasing development by a minute or two. Agfa recommends a minimum of 10ml of Rodinal stock solution, no matter what the dilution. I have to confess that I don't follow this recommendation, but it is another variable to be considered.

-- Ed Buffaloe (edb@unblinkingeye.com), October 01, 2001.

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