Film Developing Cookbook - Does one really need to overexpose T-grain film by 1-2 stops and pull process to get satisfactory results?

[Doremus Scudder]

I was hesitant to jump in on this, but after reading quite a few threads that touch on the same thing (metering technique), I'm going to ask.

When we say something like "...Your personal metering technique." What are we asking? I understand that if you a meter a scene with an slr, and I meter a scene with a pentax digital spot meter, there may be some variance. An incident meter or spot meter only work properly in one way. If we both meter a scene (the same scene for arguments sake) with the same meter that is calibrated properly, what would the variables be?
Each person's opinion regarding the important parts of the scene (shadow placement and/or highlights) are the only things I can come up with. I see "metering technique" come up a lot and am simply curious.

I feel like what we all do with what the meter tells us is where either the magic or folly occurs.

as to t-grain films, I don't consider myself a fine enough printer to know whether Tmax or Delta films have prevented me from attaining the sublime. I'm pretty happy with negatives I have from both films and lately I just try and think more about what the EI will mean regarding my exposure times in the field.

Well, I use a number of metering techniques depending on the camera I'm using (admittedly mostly spot-metering these days).

If one is using a spot meter and basing exposure on a shadow value that one wants to be rendered in a specific way, then visualization and the correlation of that with a particular desired print density/rendering comes into play. Let's say I want a shadow to be rendered as a luminous Zone IV. Well, that's my idea of "luminous Zone IV," not anyone else's. My testing and experience have taught me that if I use X E.I. and place the shadow in Zone IV and develop with XY developer for XYZ minutes with my particular brand of agitation, I can make a print that displays the density and "feeling" for the shadow that I wanted, along with my vision/desires for the other densities as well. Someone else may have a totally different idea of how Zone IV should look, not to mention where the other values in the scene should fall (which would affect development time), so may need a different E.I. to achieve those desired results. Point being, even with the exact same equipment, differences in individual approach and desired result occasion different E.I.s.

What if you use your spot meter to find an average value between the highest and lowest value you want detail in? That's going to result in a very different E.I., which will often be different depending on the luminance spread. Or if I'm using my spot meter to measure and place a skin tone, etc.

If I'm basing my exposure on an average or center-weighted value (determined by my TTL in-camera meter), I'll test to see which E.I. gives me the shadow detail I desire. This E.I. even for the same film I use spot-metering, might be significantly different, since I'm no longer visualizing a shadow value a là ZS and basing exposure on that (which generally results in a lower E.I.), but indirectly controlling shadow density by changing exposure for a metered mid-tone or average value.

If I'm using an incident meter, I might meter both in the main light and in the shadow to determine lighting ratio and base exposure on that, adjusting either E.I. or adding exposure compensation depending upon that ratio. And, what if my meter doesn't read like yours? I have several meters, only two of them agree to within 1/3 stop. I have "compensation factors" depending on which meter I'm using.

I haven't even dealt with flat or contrasty scenes, which require compensation, nor what kind of print someone likes to make; rich and full of mid-tone values, or spiky and snappy with lots of contrast but lacking shadow separation (who needs that anyway!), etc., etc.

What you point your meter at makes a difference too. Including bright sky in your meter's field most of the time? Maybe you need a lower E.I. Point your meter away from the sky all the time to avoid that? You'll need a higher E.I.

Metering techniques are highly personal, which is why E.I. is personal as well.

Best,

Doremus

 

[BHuij]

I'm a huge fan of Delta 100. While I haven't done any super formal curve building, I have done the basic sensitometry to establish my "personal" speed and development time, same as with FP4+ and HP5+ in a couple of developers. Basically finding FB+F density, then Zone III density and Zone VIII density for (N) development.

When shooting HP5+ and rotary processing in HC-110 1:50 (easier to remember than Dilution H for me... haha), I get an EI of 250.
When shooting HP5+ and non-rotary processing in XTOL stock (actually Instant Mytol, but I believe it's virtually identical in results), I get dead on box speed of 400.

When shooting Delta 100 and rotary processing in HC-110 1:50, I get an EI of 80, so just 1/3 stop shy of box speed.
When shooting Delta 100 and non-rotary processing in Instant Mytol stock, I get somewhere in between EI 100 and 125, so I shoot it at 100 to err on the side of "too much shadow detail."

Honestly I suspect it's the rotary processing more than anything else robbing me of film speed with the HC-110, since I kinda have to keep my times short or the contrast starts to run away. Maybe I ought to recalibrate with greater dilution

Not so with Rodinal, which famously costs film speed anyway, unless you're stand developing or something (and my rotary processing is basically the opposite of stand development). Rodinal 1:50 and FP4+ requires me to shoot at EI 64, and I get excess grain that makes me avoid the combo in formats smaller than 645. But it sure does make for some really nice looking shadows, in kind of an inscrutable way I can't quite put my finger on, which is what keeps me coming back in 4x5.

So if anything, my experience matches yours, in that the t-grain film I shoot is actually closer to box speed in my workflow, generally speaking, than traditional films. Though the difference is small.

Sometimes I wonder if some of the well-known teachers who got really dogmatic about various aspects of film processing were just using really weird developers, or odd processes, or if the film back then really was formulated very differently than film today of the same name.

 

[MTGseattle]

Well, I use a number of metering techniques depending on the camera I'm using (admittedly mostly spot-metering these days).

If one is using a spot meter and basing exposure on a shadow value that one wants to be rendered in a specific way, then visualization and the correlation of that with a particular desired print density/rendering comes into play. Let's say I want a shadow to be rendered as a luminous Zone IV. Well, that's my idea of "luminous Zone IV," not anyone else's. My testing and experience have taught me that if I use X E.I. and place the shadow in Zone IV and develop with XY developer for XYZ minutes with my particular brand of agitation, I can make a print that displays the density and "feeling" for the shadow that I wanted, along with my vision/desires for the other densities as well. Someone else may have a totally different idea of how Zone IV should look, not to mention where the other values in the scene should fall (which would affect development time), so may need a different E.I. to achieve those desired results. Point being, even with the exact same equipment, differences in individual approach and desired result occasion different E.I.s.

What if you use your spot meter to find an average value between the highest and lowest value you want detail in? That's going to result in a very different E.I., which will often be different depending on the luminance spread. Or if I'm using my spot meter to measure and place a skin tone, etc.

If I'm basing my exposure on an average or center-weighted value (determined by my TTL in-camera meter), I'll test to see which E.I. gives me the shadow detail I desire. This E.I. even for the same film I use spot-metering, might be significantly different, since I'm no longer visualizing a shadow value a là ZS and basing exposure on that (which generally results in a lower E.I.), but indirectly controlling shadow density by changing exposure for a metered mid-tone or average value.

If I'm using an incident meter, I might meter both in the main light and in the shadow to determine lighting ratio and base exposure on that, adjusting either E.I. or adding exposure compensation depending upon that ratio. And, what if my meter doesn't read like yours? I have several meters, only two of them agree to within 1/3 stop. I have "compensation factors" depending on which meter I'm using.

I haven't even dealt with flat or contrasty scenes, which require compensation, nor what kind of print someone likes to make; rich and full of mid-tone values, or spiky and snappy with lots of contrast but lacking shadow separation (who needs that anyway!), etc., etc.

What you point your meter at makes a difference too. Including bright sky in your meter's field most of the time? Maybe you need a lower E.I. Point your meter away from the sky all the time to avoid that? You'll need a higher E.I.

Metering techniques are highly personal, which is why E.I. is personal as well.

Best,

Doremus

Thanks. That was pretty thorough. Sorry for the derailment of the thread everyone, it was a thought I had had before when we start comparing film characteristics.

 

[Stephen Benskin]

Even if the Cookbook's evaluation isn't as anecdotal as it appears, and they conducted tests of the highest scientific standards, I can’t get past the question why waste your time using a film just to change its characteristics when you can just use a different film with the characteristics you prefer?

This is from D. Connelly’s, Calibration Levels of Films and Exposure Devices. He integrates the relationship between the metered exposure point, Hg, and the black and white speed point, Hm, into the ISO standard’s black and white speed diagram. Δ1.0 or 3 1/3 stops.

 

[dokko]

I usually expose TMX at 80-100 ISO and find the results absolutely stunning.

Here's a zoomable image of TMX in Adox XT-3 1+2, shot handheld on a Mamiya 7 scanned at 4900ppi:

dokko - example Mammoth scans

Scan at 4900ppi, TMX

dokkoscan.com

 

[John Wiegerink]

I usually expose TMX at 80-100 ISO and find the results absolutely stunning.

Here's a zoomable image of TMX in Adox XT-3 1+2, shot handheld on a Mamiya 7 scanned at 4900ppi:

dokko - example Mammoth scans

Scan at 4900ppi, TMX

dokkoscan.com

Now that's some very, very fine detail. I think you could make a wall mural from that scanned negative.

 

[dokko]

Now that's some very, very fine detail. I think you could make a wall mural from that scanned negative.

thanks. TMX actually holds even more detail, here some small crops at 11'000ppi:

 

[John Wiegerink]

I usually expose TMX at 80-100 ISO and find the results absolutely stunning.

Here's a zoomable image of TMX in Adox XT-3 1+2, shot handheld on a Mamiya 7 scanned at 4900ppi:

dokko - example Mammoth scans

Scan at 4900ppi, TMX

dokkoscan.com

Just wondering which developer was used? This says XT-3 and the ones below say FX-39II. Are they two separate pictures?

 

[dokko]

Just wondering which developer was used? This says XT-3 and the ones below say FX-39II. Are they two separate pictures?

good catch, I got confused here. the building in corfu is 99% certain FX-39II since I scanned that right after developing and put the labels on top of the image, so the XT-3 mention is wrong (can't seem to edit it anymore in the post above).

Here's a lens test with TMX (and Delta100) in XT-3 vs other developers though.. overview of the 6x6 image, with the rectangle marking the crop:

and the crop at 11'000ppi as a gif animation:

 

[John Wiegerink]

good catch, I got confused here. the building in corfu is 99% certain FX-39II since I scanned that right after developing and put the labels on top of the image, so the XT-3 mention is wrong (can't seem to edit it anymore in the post above).

Here's a lens test with TMX (and Delta100) in XT-3 vs other developers though.. overview of the 6x6 image, with the rectangle marking the crop:

and the crop at 11'000ppi as a gif animation:

I was pretty sure it was FX-39II, but it's nice to know for sure. I haven't used Tmax in years, but it might be fun to load some in my Contax G1 and see what it can do. I just bought two rolls of Adox HR50 and it might be fun to do a comparison of the two films. I have a new bottle of FX-39II on my darkroom shelf.

 

[Steven Lee]

Speed rating cannot be separated from metering technique. One can't know how much exposure the film received without knowing both.

So true. I find it mildly irritating when people drop this pointless phrase: "I rate XYZ at half the box speed". You don't get to "rate" anything! You're applying some kind of metering which you're not communicating!

 

[John Wiegerink]

So true. I find it mildly irritating when people drop this pointless phrase: "I rate XYZ at half the box speed". You don't get to "rate" anything! You're applying some kind of metering which you're not communicating!

Yes, your meter ain't my meter and where you point the dang thing ain't where I'd point mine. So, why should I use your recommended EI/ISO and why should you use mine? I think the best place to start is with the manufactures recommended box speed and do your own testing. Of course most of use know some of those manufacture inflate their box speeds just a little, which is why most folks come up with rating their films slightly lower than box speed. But we've also had folks here rate films like HP5+ higher than box speed. No film speed is etched in stone.

 

[pentaxuser]

My "take" from from various threads by the OP is that Í'd better think twice about buying this "cookbook" It seems to be somewhat unreliable and confusing in more areas than I'd expect such a book to be

pentaxuser

 

[Milpool]

My "take" from from various threads by the OP is that Í'd better think twice about buying this "cookbook" It seems to be somewhat unreliable and confusing in more areas than I'd expect such a book to be

pentaxuser

The cookbooks (FDC/DC) are not confusing to read. The writing is very straight forward, the basics of developer constituents are ok, and there are some interesting historical notes. It’s the extrapolation and extension of these basics into recommendations and assertions (particularly in light of the evolution of emulsion technology) which are problematic. As is often the case with these kinds of books, there is no sensitometry, and things tend to veer into hyperbole.

Of course there’s nothing wrong with trying things and experimenting (it’s part of the hobby). However nothing in these books is going to improve results versus plain vanilla, off-the shelf Kodak, Ilford etc.

 

[Alan Johnson]

I think the comment in FDC 1998 probably came about because this was soon after T-max 100 replaced Panatomic-X and some (many?) photographers wanted the look of Panatomic-X back.
This is a minor point compared to the excellent explanations of the differences in the various developers which makes the Film Developing Cookbooks useful.

 

[DREW WILEY]

The ideal exposure prescription has nothing to do with the T-grain per se, but with the characteristic curve of T-Max films. which has a relatively long straight line deep down into the shadows, allowing realistic shadow value placement quite low, even at full box speed of 100 (or 400 in the case of TMY400). That is dependent on the specific developer of course. But with nearly all the common ones, it holds true.

On the other hand, Delta 100 (Ilford's T-grain film) has somewhat more toe to its characteristic curve, so when shooting high contrast scenes, you need to give extra exposure by cutting the box speed in half in order to get shadow gradation equivalent to TMax films.

Going back to the original post, referencing what the "Cookbook" sidebar allegedly said - well, it sure doesn't sound like any restaurant I'd want to eat at. It got it all backwards and nonsensical. But I've only been shooting TMax films ever since they were first introduced, and in multiple formats all the way from 35mm to 8X10, including for portraiture.

These films are especially development malleable if you understand them. That's why TMax replaced an entire suite of previous Kodak films. That apparently bothered many practitioners who preferred one-trick ponies for certain specific applications. But the only dinosaur which somehow survived the TMax asteroid impact was Triassic-X.

My wife once took a college photography class where the instructor was constantly bashing Tmax, and called it the worst film ever. When the students were assigned to go out and take some shots and print one of them in the darkroom, hers was singled out as the best of the lot, and even a classic in his opinion. Then when he asked what film she had used, she replied in almost a whisper, TMax. Things went awful quiet awful fast. Of course she had some tips from me how to properly expose and develop it.

I've personally used many different films and developers, and have reasons to love all of them, provided it was an appropriate application. T-grain films are a little fussier than most other ones in terms of exposure and development technique. But there are also exceptional rewards working with a high-performance film.

 

[Stephen Benskin]

Of course most of use know some of those manufacture inflate their box speeds just a little, which is why most folks come up with rating their films slightly lower than box speed.

I don't believe there is good evidence to draw such a conclusion. Other reasons, including those you have stated, have a more practical explanation for the perceived discrepancy.

 

[Alan Johnson]

I quote a little more from the sidebar on p19 of FDC 2020 :
"Most people at Kodak involved in the T-grain program believed that when T-Max 100 was overexposed and underdeveloped, it matched or exceeded the quality and subtlety of Panatomic-X. Similarly, T-Max 400,exposed at 100 and suitably developed, is a viable alternative to Plus-X and even Verichrome Pan......"

It is mistaken to think that the authors are claiming that tabular grain films have normally to be overexposed and underedeveloped, their claim ,supported by the Kodak workers, is that this can be done if it is wanted to simulate these other films. This seems to be rarely done in present day times but it does seem to have led to some misunderstanding of the sidebar.

 

[DREW WILEY]

What on earth was meant by "Pan X subtlety and quality"? The wording is indeed ambiguous. Potentially mimicking the Pan X look, sure. That's why Pan X was yet another film upended by the TMax revolution. But the stated technique for how to do that would actually diminish what TMax qualitatively does better in its own right. TMax can simulate quite a variety of films if specially developed to do each of them respectively. I know how to even simulate Pan Masking Film with it, or at the opposite contrast extreme, replace Super-XX. Tech Pan?- not quite; that was a different animal altogether.

 

[Augustus Caesar]

I don't believe there is good evidence to draw such a conclusion. Other reasons, including those you have stated, have a more practical explanation for the perceived discrepancy.

No, it's not the companies that over-rate their films. They use ISO standards. It's those standards that are the problem.

 

[Stephen Benskin]

No, it's not the companies that over-rate their films. They use ISO standards. It's those standards that are the problem.

As with most things, the standards need to be adjusted from time to time. What is their problem? How should they be fixed?

 

[honerich]

No, it's not the companies that over-rate their films. They use ISO standards. It's those standards that are the problem.

Which company uses ISO standards? I don't know any!

Foma's box speed definitely is too high with any standard developing process.

The Ilford film data sheets state: “It should be noted that the recommended exposure index(EI) is based on a practical evaluation of film speed and is not based on foot speed, as is the ISO standard.”

Kodak uses a Contrast Index CI, that has nothing to do with the definitions in the ISO standard. CI can only be evaluated in a graphical manner with a special ruler and cannot be converted into Ilford's G or into gamma.

The only way to deal with this is to carry out your own film tests and use your own personal EI.

The density curve used in ISO (see #29 above) has nothing in common with a typical curve of modern b&w films. This ISO standard is completely outdated and is obviously ignored by today's suppliers.

 

[Chuck_P]

 

[runswithsizzers]

@honerich: "The Ilford film data sheets state: “It should be noted that the recommended exposure index(EI) is based on a practical evaluation of film speed and is not based on foot speed, as is the ISO standard.”

Ilford uses that statement ONLY for their Delta 3200. The data sheets for all their other films state the films ISO rating, similar to this:
"FP4 Plus has a speed rating of ISO 125/22º to daylight. The ISO speed rating was measured using ILFORD ID-11 developer at 20ºC/68ºF with intermittent agitation in a spiral tank. ..." The Delta 3200 data sheet states, "...the ISO rating DELTA 3200 Professional has an ISO speed rating of 1000/31°..."

The Ilford data sheets do go on to discuss EI recommendations, but except for Delta 3200, the numbers on the film box are derived from ISO testing. Notice the packaging shows "EI" for the 3200 and "ISO" for the HP5+...



If it says "ISO" on the box, then I believe the film has been tested according to the ISO standard. How the user applies that number when exposing the film is a different matter, as this thread demonstrates.

 

[Stephen Benskin]

Maybe someone could move the last few posts to a new thread.