Tmax Motion Picture Film

[EKDobbs]

I recently acquired some Tmax (400?) 35mm motion picture film. It's from the 70's, and has been in cold storage for most of its existence. I'm unsure if there are any major differences in how this film must be shot/developed as opposed to regular "picture" film. I was thinking I would stand develop (in D-76) it and see if that could ascertain the correct ISO.

 

[Ian Grant]

It's not that old it was introduced in the mid 1980's,

Not sure that stand development is needed though it would be better to do a film speed test to check it properly.

Ian

 

[EKDobbs]

I'm not entirely sure how to do a proper speed test. I don't think my eyes are attuned enough to tell the difference between errors in exposure and errors in development. If it's 200 ISO and I shoot it at 200, but develop it at 400, how would I know what went wrong?

 

[nickrapak]

TMAX MP film? If that's what you really have, and not just a long roll of 135, you have a rare beast indeed. It was only ever produced as a test, because Kodak found no difference in apparent grain and an effective speed loss compared to Plus-X/Double-X.

 

[Bill Burk]

There's plenty of indepth discussions on APUG to explain how to do a speed test... Here's a synopsis:

Get a sensitometer (or at least a Stouffer step wedge). Use it to expose some known good fresh film. Get a densitometer (or enlarging meter and compare the step wedge to your negative) and read the densities and graph them... When you get a graph that agrees with the ASA parameters, then you have a benchmark to compare against.

Expose and develop your unknown film. Development time to agree with ASA parameters will be different but can be found by several trials. The difference in the x-axis of the unknown film and the known film can tell you the speed of the unknown film.

 

[EKDobbs]

TMAX MP film? If that's what you really have, and not just a long roll of 135, you have a rare beast indeed. It was only ever produced as a test, because Kodak found no difference in apparent grain and an effective speed loss compared to Plus-X/Double-X.

I believe it is motion picture film, and the canister does claim that it's Tmax. I have no proof, and don't really care either way.

I suppose I'm just going to shoot enough rolls of it to tell what the ballpark ISO is. I'm not really in the financial situation to get a sensitometer, and I'm not exactly sure how those step wedge things work. (I'm lazy. Sue me. )

Anywho, thanks to those who responded for the help.

 

[ic-racer]

You don't need a sensitometer if you have a light meter.
The exposure index test ('film speed test') is simple. Meter a uniform illuminated target at your guess exposure index and under expose it by 4 stops when you make an exposure of it with your camera. Process the film and use your light meter to test the film. If the exposed film drops the meter reading by 1/3 of a stop (compared to a blank frame) when placed over your light meter sensor, you know the exposure index you selected is good.

T-max film was not made in the 1970s as far as I know, but even T-max 400 from the 1980s will be pretty useless by now. I still have some Ilford HP5 in freezer storage since the early 1980s and the base density is approaching 0.7 log d.

Again, to test the base density, you don't need a densitometer. Just place some processed but unexposed film over your meter. Every stop of indicated exposure the film sucks up is 0.3 log d.

In terms of motion picture film, you can check the perforations. Motion picture film has more rounded perforations (BH) where as 35mm still camera film has more rectangular perforations (KS).

 

[Bill Burk]

Well, a step wedge will set you back about six bucks, and if you already have an enlarger you can check out the "enlarger as sensitometer" thread... Then the only awkward trick is to expose the strip onto the film... after you develop you'll have a strip that goes from clear to black in a certain number of steps... You can compare it to the original step wedge (for example, find the step on your test that matches the original step #9).

 

[Arvee]

Why not do a snip test? In a changing bag snip off about 6-10" and load it into a developing tank and develop normally in D-76 at recommended time for TMAX 400. Wash and fix normally.

When dry check the edge markings for good density and also you will have the film type - should be 5063 if I recall correctly. If you have good density on the numbers you're probably good to go.

I just received from a friend a frozen brick of Tech Pan and four rolls of PX dated in the late 80s. I tested a roll of each and they were fine with just a hint of fogging.

 

[Bill Burk]

I'm lazy. Sue me.

Haaaa, Guess you won't be signing up for my class "Calling your shots, the timeless appeal of popular sensitometry"

Shoot it at EI 64 and see what you get. If there is a lot of fog, that'll blast right through it.

If it comes out clean (you have little fog), nudge your way up towards 400.

 

[AgX]

In terms of motion picture film, you can check the perforations. Motion picture film has more rounded perforations (BH) where as 35mm still camera film has more rectangular perforations (KS).

BH perforations have straight long sides and curved short sides and sharp corners.

KS perforations are rectangular (all sides straight) but with rounded corners.

 

[nworth]

Shoot a short roll at both 100 and 400, then develop it as for TMAX 400 still film and look at the results. You will get a decent idea of the speed, and the edge marking will tell you what kind of film you have. Long rolls of TMAX still film will be marked "Kodak TMAX" and the film speed, and the film will have frame numbers running from 01 to 44, repeating for the length of the roll. Motion picture film will have an identifying code and short dashes for frame markings.

 

[Arvee]

Apparently Kodak tested and rejected TMAX for MP use.

http://motion.kodak.com/motion/support/Technical_information/faq.htm#preprod14

Look under PreProduction asking the question why Kodak chose not to spool TMAX as an MP film stock.

 

[AgX]

Thank you for hinting at that Kodak statement.
But except of that fixer issue it seems enigmatic to me.