Help with Tmax400, highlight, EI/ISO. Waaa!

[tkamiya]

I have been having rough time with Tmax400... and I'd like to get some help.

So far, by reducing development time to -15%, I got contrast to be ....just....right.... Not too contrasty, not too bland and boring. I typically rate ISO = EI.

Now... if I rate this film at EI = 200, I know I am over exposing it by 1 stop. That will make shadow part of film little darker than really thin which in turn will bring out shadow detail. BUT, what happens to the highlight? Wouldn't that make already very dark portion of the film even darker and possibly too dark, ending up with loss of highlight detail?

Wouldn't that also make darker negative over all, which will lengthen printing time?

For an experiment, I rated this at EI=320. Using my standard contact print time, the contact sheet ended up little lighter than usual. I'd like to understand the logic behind this, so I am clear on what happened.

Please.... no argument on EI and ISO and how and if this is even beneficial. I've read them already. All I need is your help on understanding the logic behind all this "stuff". Thank you.

 

[MattKing]

I'll see if I can help a bit with this.

Tmax400 (TMY) has the ability to hold detail over a very wide range of light intensities, and much of that range is very linear. This means that if you are photographing a scene with a fairly wide range of luminances (brightness), and decide to meter at an EI that is lower than 400, most likely you will move the shadow densities up into the linear part of the curve, and the highlights will probably still be in that linear part too.

That being said, your shadow and highlight densities will be accurately recorded, but a long way apart as far as density - probably farther apart than can be accurately recorded on photographic paper if you:

1) print the image straight (without large amounts of burning and dodging, or contrast masks or other intensive measures); and
2) print the image at a contrast rating close to neutral ("grade 1.5 to 2.5").

Now when you do a contact sheet, you usually don't do much burning and dodging, and you usually use something like grade 2 (and if you use a contrast mask, you are very rare). But there is no reason you need to approach making prints in the same way. Instead, you would choose a contrast grade that gives you the mid-tone contrast you want, and use burning, dodging, split-grade printing techniques and other techniques to get the details, densities and contrast you want in the shadows and highlights.

If your original scene has a narrower range of tones, the printing may be straightforward.

Hope this helps.

 

[MartinCrabtree]

While we're in this neighborhood. Could someone clarify for me why paper hasn't the latitude of some films? Are the limitations insurmountable by modern technology?

 

[tkamiya]

Greg:

Right.... I use condenser type enlarger and I read that portion of the note.

I played with 0%, -10%, -15%, and -20%. With my idea of "perfect" seems to fall somewhere between -10% and -15%. -20% created really thin negative. At 0%, it was way too contrasty.

Thank you.

Matt:

Thanks for the discussion of film contrast range can exceed that of paper. I was wondering about that, too. I thank you, too, on explanation of curb shifting UP and likely still be in the straight portion, so no loss will occur.

 

[tkamiya]

Martin,

Maybe I can help... The way I understand it, image on paper is REFLECTIVE. That is, an external light must reflect on paper to reach your eyes. A white paper can only reflect so much. There is never such thing as "pitch black" that reflects no light at all. Therefore, the range of full reflection to almost no reflection is much narrower. (than that of film which will transmit light through)

 

[2F/2F]

Down rating your film does only one thing: changes exposure (increases it, to be more specific) across the board, meaning in all shots in which the rating is used. The only thing rating a 400 film at 200 does is to apply a built in exposure compensation of plus one stop.

So, in short, the answer to your question is YES. When you increase exposure to change the density of certain areas of the film, every other area increases along with it. Since the whole frame is exposed all at once in the same exposure, this is how it must be.

Changing development simply changes contrast. This is true within a certain exposure range, in any case. In an instance of the contrary, an extremely unexposed - i.e. mostly blank - negative won't really have it's contrast changed in a significant way even if you develop it forever. However, as long as there is above a certain threshold of "meat" on the negative ("meat" meaning exposed silver halides), the general statement I made holds true.

In short, the light in a scene and the exposure setting used to control your film's exposure to that light determine how intensely the silver halides are exposed. Development controls the densities at which metallic silver is formed from areas of silver halide that have received a certain amount of exposure. The more exposure to light a silver halide has experienced, the faster it will convert to metallic silver upon development. This means that the amount of exposure you give to certain areas not only affects their final density, but effects how quickly the developer will act on certain areas of the film.

To say it again another way, more exposure to light makes a silver halide more sensitive to developer. Since any pictorial negative has areas that have received more exposure than others, and other areas that have received less exposure than others, there will always be areas of the negative that are more sensitive to development than others. Thus, variations in development time on any negative containing more than one tone must vary contrast. You see that exposure and development are a "team" that work together to determine what you get on your negative.

In general, I think it makes much more sense to simply use box speed, learn the contrast you get on your film with different developing times, and to simply manually overexpose your film only in shots in which overexposure would be beneficial, not to automatically over expose every shot by downrating the film. Overexposure does not benefit every shot, though this seems to be a prevailing belief among photographers shooting negative film. Overexposure can be more easily adjusted for in printing than underexposure, so it is generally better to be over than to be under. However, this is not the same thing as saying that overexposure is good for every picture. It is not even close to the same!

The thing that rarely seems to be driven home in all this re rating stuff that flies around among photographers is that you must develop an eye for luminance range in your compositions, and/or use a meter to measure it, and that you must also learn what luminance range a film can capture when exposed and developed in various ways. There is no magic bullet film rating and development that will work across the board in every picture you take. You need to know your light, know your film, know your process, and learn how they all come together so that you can manipulate these three things to get what you want when printing.

 

[tkamiya]

2F/2F:

Thank you for the explanations. Yes, I do know, re-rating = over/under exposure by corresponding stops. The rest of the stuff, I really don't want to get into, in this thread. I was only trying to understand exactly what happened in my experiment.

Right now, I am very pleased that I finally got the contrast I want. I'm on to next step. Therefore my questions.

Thanks again.

 

[2F/2F]

The interesting thing about T-Max, and many other "modern" films is that exposure variations affect contrast far less than they do with "older" emulsions. As someone explained above, this is due to the films' inherent designs of having long straight lines. Working with HP5 is entirely different than working with Delta 400, for example. The way you would expose and process each when using them to photograph an identical composition and lighting can be quite different.

(Maybe this is in fact not the the interesting thing about "modern" films, but about the "older" films, since so many photographers are now used to the look that comes from imaging media with long straight lines.)

 

[tkamiya]

I actually like the look of Tri-X400 better.... I can't really explain why though. Maybe because last time I played with film was 25+ years ago and that's what I remember.

 

[fschifano]

While we're in this neighborhood. Could someone clarify for me why paper hasn't the latitude of some films? Are the limitations insurmountable by modern technology?

I don't think it's so much a question of it being impossible to make a paper that will record as wide a dynamic range as film. It's more a question of how it would look - pretty dull. Take a normal contrast negative and print it on #2 or equivalent. Looks pretty good right? Blacks are good. Mid range has good separation. Highlights are not too light and still have some detail. Now take that same negative and print it on a soft grade of paper. Looks pretty crappy. If everything goes well, it will look dull and lifeless. Well, that's essentially what you're asking for, a very low contrast paper - lower contrast than even the softest paper. Sure it can be done. The technology is in every pack of variable contrast or soft grade paper. It won't make a good looking print though.

 

[2F/2F]

What you probably like about TX is:

Its inherently (i.e. "out of the box") different tonal response to light ("wonkier" curve shape)
Its different spectral sensitivity
Its different sharpness
Its different rendering of grain

...because those are the things that are notably different between it and T-Max (and between any one film and any other film).

 

[MartinCrabtree]

I don't think it's so much a question of it being impossible to make a paper that will record as wide a dynamic range as film. It's more a question of how it would look - pretty dull. Take a normal contrast negative and print it on #2 or equivalent. Looks pretty good right? Blacks are good. Mid range has good separation. Highlights are not too light and still have some detail. Now take that same negative and print it on a soft grade of paper. Looks pretty crappy. If everything goes well, it will look dull and lifeless. Well, that's essentially what you're asking for, a very low contrast paper - lower contrast than even the softest paper. Sure it can be done. The technology is in every pack of variable contrast or soft grade paper. It won't make a good looking print though.

Thanks Frank. Didn't think of it that way.

 

[tkamiya]

That... kind of begs another question...

Since Tmax is so capable of capturing wide range of luminance levels, in far excess of capability of any paper.... if I expose and develop it to use full range of luminance levels, then there will be no way to put all *that* range on paper, correct? Then, I would have to employ various technique to make local adjustments (dodge/burn), various filtering techniques, etc to smush all that into basically 5 stops that paper is typically capable of representing.

Or - I could develop it in such a way that contrast range gets narrower, in zone system's terms, N minus, then print it more less straight with some adjustment by grade filters.

I have been using Tmax in rather hap-hazard way and developing it in such way that latter is more less possible. Otherwise, I ended up having way too much contrast on paper or have highlight get so blocked they look pure white.

Am I basically wasting true capability of this film?

 

[MattKing]

The thing to remember about all these issues is that the goal isn't to fit the subject into the materials, it is to make the result look like the subject (or possibly how you would like the subject to look).

That is why I always suggest concentrating on the mid-tones. Generally speaking, if you get the mid-tones looking good (density, detail and contrast) then the image will look well printed. This may mean you have to work a bit to get details, texture and darkness in your shadows and details, texture and sparkle in your highlights, but when you do, the whole print will look best.

If you reduce the global contrast (either on the negative or while printing) you may fit everything in on the paper, but the mid-tones are likely to look flat, drab and lifeless.

 

[tkamiya]

Matt,

What do you mean by "work a bit?" Dodging and Burning? Of course, I try to get my main subject (and interest) to look just right. But, the problem is.... what's around the main subject. Let's say I'm outside in bright sunny day. My subject may be a person wearing white shirt. (I actually tried something like this) Let's say the person is an Asian so skin tone is close to 18%. If I develop normally, face might look right but shirt will be unprintable without heavy burning. Hence my effort to *smush* everything.

How would you handle this?

 

[MattKing]

Dodging and Burning are my most used tools.

Don't forget that if you are using variable contrast paper, you can use different contrast settings/filters for your dodges and burns than those you use for your main exposure.

For the sunlit white shirt, I'd definitely experiment with split grade printing using the low contrast filter to print until I detected the first hints of detail in the shirt. Dodging of the darker parts of the image during that part of that exposure might be necessary.

Also, you need to decide whether detail and texture in a sunlit white shirt is even necessary - in everyday life we don't necessarily expect to see much.

 

[df cardwell]

TMAX 400 an an extremely long scaled, linear film. HOWEVER, it's actual response is the product of the FILM and the DEVELOPER.

Developing TMY2 in different developers, in other words, will give you a different curve SHAPE.

SO, if you want some accurate help, tell us what you are developing your film IN, and how long you are developing it !
Kodak's published information about TMY2 development is very reliable.

AS for exposure, TMY2 pretty much always gives a linear scale (some exceptions) and can hold a scale far longer than anything you're likely to be shooting. This means you have great latitude for over exposure without changing the tonal relationship of the picture. But USUALLY is not ALWAYS. Let us know how you are developing the film.

 

[tkamiya]

I use XTOL at 1:1 dilution. Percentage reduction from published development time is in my original post. (-15% being the latest trial) My agitation schedule is, 5 initial inversions and 2 inversions every 30 seconds.

I also have D-76 but I have not tried it with Tmax.

 

[df cardwell]

All I need is your help on understanding the logic behind all this "stuff". Thank you.

Well, logic is not the problem. Finding the right premise is the problem. I'd suggest that you begin with the premise that Kodak's data is correct, and any deviation from it will fall either to your exposure meter or your printing paper and its developer.

Kodak's times for Xtol and TMY2 are exquisitely close to perfect, for 1+1 dilution (with agitation every half minute.)

That gives an EI of 400, and a straight line that begins at Zone II and runs up to about Zone 14 or 15. If that negative isn't fitting (with a diffusion enlarger) a 10 step scale on fiber paper, you need to look at your system and see what is causing the problem.

I'd suggest using Kodak's time and see what your EI should be, but we can't talk about that.

We spend a lot of time doing funny film tests, but with a developer like XTOL and a film like TMY2, you really only need to do a test for middle gray, since middle gray is the product of EXPOSURE and DEVELOPMENT. We know from YEARS of published data that XTOL and TMY2 = linear curve over a long scale. If you aren't able to print it, the cause is probably in the paper & developer combination.

If you are using a condenser enlarger, then simply reducing the development time might not put you where you ought to be. The problem is that if you shorten the development time too much, the scale is no longer linear. If it were me using a condenser head, I'd use the longer time, and a softer paper developer.

Good luck.

 

[ic-racer]

I know I am over exposing it by 1 stop. That will make shadow part of film little darker than really thin which in turn will bring out shadow detail. BUT, what happens to the highlight? Wouldn't that make already very dark portion of the film even darker and possibly too dark, ending up with loss of highlight detail?.

Maybe a lesser film, but not T-max

 

[Andrew O'Neill]

Developing TMY2 in different developers, in other words, will give you a different curve SHAPE.

Exactly. And TMY is one of the most responsive films out there to different developers and dilutions. If you ever get a chance to read the late Phil Davis' article on tonality (PT mag back issue), read it.

 

[Harry Lime]

I've been rating TMY-2 400 @ 400. It is different than Tri-X (which I shot for the past 12 years). Far more linear and over or under exposing just seems to shift the curve either up or down, while maintaining that linear response.

I develop in Barry Thornton's 2-bath and the tonal scale just seems to go on for ever (while remaining linear). Blown out highlights have not really been a problem, since I got some experience with the film. The main problem almost seems that TMY-2 exceeds the range of my scanner...