TMAX exposure index

[Fred Braakman]

I went out today and shot a few sheets of TMAX 100. I inadvertantly metered the images with my spot meter set at 50 ASA. I had meant to shoot them at 100 ASA. I have not shot a lot of TMAX 100, but I had shot them previously at 100 asa.
Have I overexposed the film, or can I still recover by development?

Fred

[Brian Ellis]

Have you tested and determined that 100 is your correct EI or are you just using 100 because that's what it says on the box? Many people rate TMax 100 at 50 to ensure adequate shadow detail. So if you're just using 100 because that's what Kodak says then 50 may actually be better than 100 and certainly shouldn't be a serious problem. If you've tested and determined that 100 is your EI then you've overexposed by one stop and that too isn't usually a serious problem with b&w film. If you know you're overexposed by a stop (i.e. you tested to determine that 100 is your EI) then you might reduce development time by about 15%. Otherwise I'd just develop normally.

[Eric Brody]

What developer do you use? Some, like Xtol, which I use, for example, seem to allow EI 100 with Tmax 100. Others seem to test out with a lower EI. As an example, many people rate Tri-X at 160-200 when used with HC-110 rather than the 320 on the box.

If you usually rate at 100 and are happy with your shadow detail, whatever the developer, you're probably ok regardless with a 1 stop overexposure. I have a densitometer and over the years have spent way too much time testing. Some people fuss about these degrees of precision more than others. There's a huge range out there from those who develop by inspection, something I've never quite understood, to those Zone system folks who really get off on testing... endlessly.

I suspect you'll be ok. Over my 40+ years of developing film, I have erred more often at underexposure than over. A little more light is usually good. Some of the best printers I know have negatives that often seem quite dense.

Good luck.

Eric

[Andrew O'Neill]

You should be okay. When I was using tmax 100 with xtol 1+1, my EI was 64. If you normally shoot it at 100, you may want to pull back on development slightly.

[Ken Lee]

The only danger is if you intend to scan, and the subject contained a lot of high values - which will now be too dense for your scanner to read, or read well. In that case, it's best to cut dev time. With a good B&W film, it's better to overexpose than underexpose.

[IanG]

Fred, I've been shooting Tmax100 since it was released and almost always at 50 ISO in Rodinal 1:50 or Xtol (replenished) and now Pyrocat HD

The Kodak leaflet actually recommended 50ISO for better tonality, and this was also the recommendation of John Sexton.

[Ed Richards]

> The Kodak leaflet actually recommended 50ISO for better tonality, and this was also the recommendation of John Sexton.

But was that before they reformulated?

[IanG]

> The Kodak leaflet actually recommended 50ISO for better tonality, and this was also the recommendation of John Sexton.

But was that before they reformulated?

Yes, your right it was. I think I'm still shooting the older stock though, actually I know I am in 5x4.

Have you tried searching the Kodak website for Tmax, it comes up with 6 different Twain drivers . . . It is there though but tucked away.

Ian

[PViapiano]

John Sexton shoots TMX at 80 and TMY at 320.

I think his TMax page and recommendations are on the LF home page...

[Eric Brody]

I believe John Sexton develops in Tmax developer which gives less film "speed" than xtol.

Eric