Exposure and T Max 100

[tim_gee]

I've done very little B&W and so thought I'd put a roll of T Max 100

through my M6ttl using my local processor to do the developing and

prints.

Quite a shock when about 33 out of 36 were all underexposed by about

a stop in his assessment. Now I've never had exposure problems like

this before so we did a think. He asked if I set the M6 to 100? I'm

almost certain I did because I had 400 in it before. That left the

shutter or meter in question. As I'm leaving for 5 weeks overseas in

9 days (prints and slides)I quickly had both M6s checked. The tech.

said they were spot on except the meter in M6ttl in question was

about 1/4 stop under - not enough to worry about.

 

So my question is: How much lattitude is there with T Max 100 and

could it be that he has mucked it up (no recriminations but I'm

wanting to get to the bottom of this if I can) I know he doesn't do

much B&W but he is a pro after all. Could he get it that wrong or is

the lattitude so limited that I,m not being accurate enough?

What say you good people.

[walter_a._muller]

At our large-format class at Scottsdale Community College, the instructor(Rod Klukas)starts his students out with TMax 100. He also checks individual camera, lens and exposure meter combinations for each student's personal EI by a desitometer reading (film base plus fog)of their exposed and developed film. In his years of teaching, he has yet to read an EI of 100. Usually the EI is 50, though mine is 80. He also reads the necessary development time. This procedure is very common, and is adviseable for the optimum results with any film.

[tim_gee]

Walter,

Forgive me, but I think I follow what you are saying. Is the implication that most will need to set their ASA at 50, some at 80 and probably nobody at 100 for T Max 100? and how critical is it anyway?

[steve_barnett2]

Tim, T Max 100 is fairly forgiving, and you shouldn't have any problems rating it at 100. But where are you reading from? If you have done very little B&W you may still be in the habit of reading from the highlights, or an overall high key reading, of a subject. In B&W you really need to read from the shadows, or at very least a mid tone. The detail in highlights will still be retained in B&W unless the contrast range is extreme. The alternative to a shadow reading would be to carry on pointing your camera at the subject as you have, and lower the ASA to 50, like Walter says above. This way you give the film the necessary exposure.

[tim_gee]

Thanks Steve that's helpful,

 

As more of a guide, how would you meter the T Max compared with say Sensia 100 slide film?

 

I certainly don't meter from highlights. I usually wave the M6 about, typically taking most notice of readings 45 deg. down from the subject (rough rule). I guess that's mid tones.

[olivier_reichenbach]

Just a little refresher: did you have snow in your pics? Or strong skys or backlights? Were you

on a beach with bright sand? As you know, all these situations will underexpose if you don't

compensate enough, and sometimes a lot. Snow may call for up to one and a half stop. That's

cutting your ISO by more than half. Why don't you just shoot a roll at 100, two shots of the

same frame, one metered with an incident meter (metering in the same light as your subject, of

course), the other with the reflective meter from your M, using your normal metering technique?

Make notes, compare. If your meter is correct, then either your metering technique is at fault, or

the lab is. But then, the whole 36 pics would have been underexposed. Only my $0.02 FWIW

:-)

[tim_gee]

Sydney in summer Oliver so definately no snow but equally not many shots were taken where ev compensation would normally be indicated.

33 or when I really look at them all 36 were underexposed. It could well be my technique but I've never had a problem with color. Perhaps I should bracket shots and take notes as you suggest. I was hoping to learn just how critical T Max is compared with say Sensia 100 to get a yardstick.

[greg_smith4]

Tmax is not a very forgiving film. Try shooting it at 80.

[lee_shively]

Tim, I'm not a fan of TMax films. They are a bit fussy about exposure and development in my opinion.

 

I recently shot several rolls of HP5 that were underexposed about a stop. I was shooting with 21mm lens on an M6 and I went by the in-camera meter for all the shots. The wide angle view of the meter read too much of the overcast sky above my main subjects and I failed to pay attention to this. If you were shooting with a wide angle on the M6, you may have been getting a false reading from bright areas in the scene. It's a thought.

[chris_peterson1]

Tim, I've shot quite a bit of both films, though I've just bought a

Leica. A general rule is this: You can overexpose a black and

white film, but you can't overexpose slides. Having said that, I'd

expose black and white for shadows (or something close) and

you can burn in your highlights later. With slides, you expose for

something close to highlights (but not necessarily the highlights

themselves) and let the shadows fall wherethey may. With slide

films, shadows hold detail extremely well. With black and white,

it's amazing how much highlight can be burned back in.

[john_r._fulton_jr.]

Last time I shot TMAX100 I shot at 50asa. Worked great.

[nicholas_fiduccia]

Tim,

 

I would recommend that you develop B&W yourself so that you

gain uniformity of the exposure process. I develop in my

bathroom and load film in the laundary room (the only room in

my house with no windows). The costs of a kit are minimal.

 

Once you are set up, you can test the film to get your personal EI.

For the record, I expose TMAX100 at EI of 80 and develop in D76

1:1, 68 degrees for 12 minutes. My agitation is vigrorous for 5

seconds every 30 seconds. Enjoy!

[walter_a._muller]

Tim, Good morning from near Phoenix. While I was sleeping, this thread has really grown! I don't know how critical the ASA is; I just use the 80 number and go on from there. I get pretty good consistency with my exposures. I usually meter for zone 3 and check what is included in the zones above to see if a normal development will work. I have been using Tmax 100 for several years, and have even used TMY 400 at 320 and it was spot on for a night shot. But, I must admit, I have a package of TriX 400 on order to see if I can take advantage of the greater latitude it is rumored to offer! Until I can get the film checked with a desitometer, I'll go with 320, 80% of 400. I'm attaching (I hope) my night shot. Walt<div></div>

[john_hicks___]

I calibrate all my meters to read Sunny f16 off a Wallace Expo-Disc; my M6 classic and TTL both need +2/3 stop for a Sunny f16 reading, or for example, TMX would get rated at EI 64.

 

An exposure of this results in about .10 DU above fb&f for a Zone I exposure, so I know it's correct, or about as correct as it can get.

 

Anyway, TMX has pretty much zero tolerance for underexposure.

[tim_gee]

Many thanks everyone.

 

My conclusion is that with color prints and slides I'll keep waiving the M6 about as usual to get the mid tones or the particular surface I want being particularly careful not to overexpose the slides. On the other hand with the T Max 100, set the asa to 80 and bias ever so subtly towards greater exposure remembering that under is worse than over.

Thanks again. Regards,