Assessing film speed and development time without a darkroom.

[LabRat]

"Bracketing" is a smaller than large format option, as it's no big deal to just wind another frame forward to try different settings, but in LF, sheets take up a lot of "real estate" and costs (film, processing, handling etc)...

In pro color chrome LF shooting, the film latitude is narrow so essential to nail exposure through careful metering, care in lighting where someone good could pull perfect exposure even without a "pull-o-roid", but usually we would shoot four sheets of chrome film at a single setting, and off to the lab to process one sheet at a time... First sheet was called "sacrificial" processed normal on the automated E-6 line and looked at on the lightbox... If a little dark/light, next sheet was compensated then... If all was well, other sheets were processed, or one could be held for further testing so last shot could be safe (if still issues)...

But for B/W, not as critical as chromes, but sometimes multiples if concerned about handling issues, dust etc... But it creates a burden just shooting an additional sheet each shot, as that doubles the film amount and processing runs... (I had read Dorothea Lang only shot one sheet of film each shot as that "doubled" everything...) But I still am superstitious if all that set-up for one sheet, and is that enough insurance if one sheet has issues for an important shot??? Maybe two just in case, but same exposure, maybe different aperture for DOF effect...

Generally, for "normal" scenes/processing B/W, about 1/3 to 1 stop overexposure (from "box" speed) ensures good shadow detail, then about 10% underdevelopment ensures good highlight detail without blocking up highlights and prints well with no to little burning/dodging...

For process testing, maybe a few test sheets are ok, will save other sheets down the line...

Steve K

[JohnF]

Generally, for "normal" scenes/processing B/W, about 1/3 to 1 stop overexposure (from "box" speed) ensures good shadow detail, then about 10% underdevelopment ensures good highlight detail without blocking up highlights and prints well with no to little burning/dodging...

For process testing, maybe a few test sheets are ok, will save other sheets down the line...

Steve K

But developer dependent? I have been following Peter Finch's 'Pictorial Planet' Youtube feed https://www.youtube.com/watch?v=fIdQ...ictorialPlanet on testing FP4+ with Crawley's FX55 developer where his admittedly personal results suggest exposing FP4+ at ASA 200-225 with FX55

[Alan Klein]

Bracketing exposures on film remains an extension of not fully understanding the limitations_abilities of ALL the photographic materials and process involved with print making and the image maker's print goals. This included having and knowing how what tools are required and using them to the best of their abilities and capabilities.

To gain understanding and behavior of photographic materials demands testing ... as was the beginning of this LFF "discussion".
In the specific case of color transparency film, this previous post examples how this was done decades ago as a common daily event.
https://www.largeformatphotography.i...perfect-quot-)

Once actual film speed to produce a given density and overall color balance of the color transparency film has been measured and determined, these metrics become the basis for how that specific lot/batch of film will be exposed coupled to the limits of the dynamic range of color transparency film. Much identical applies to B&W films like Kodak TMax... Don't believe for a moment B&W film is more forgiving than color.. to achieve GOOD print results demands the same degree of attention to testing as color transparency film. Doing less results in wasting photographic materials, YOUR time (not replaceable once spent), YOUR resources and much more..

The working "pro" foto industry back then developed specific tools to stop the practice of bracketing film exposures by applying science and technology to remove the need for bracketing exposures which is in many ways guessing to deal with uncertainty.

Clip from Sinar Info# 31 on Contrast Control..
Attachment 229924


It is much about fully understanding the dynamic range and Latitude of a specific photographic material. It is why and how the Sinar ground glass metering system came about.. This is also why properly using a GOOD accurate/precise spot meter can work wonders to eliminate bracketing exposures.. to about zero.
Attachment 229925

Back in them days of color transparency film centric images for color printing and other means of printed materials, Fotographers that bracketed their film exposures lots were considered incompetent and "lesser" in many ways as long experienced working "pro" photographers considered exposure bracketing a serious wast of film and much more.. This discipline of making each and every frame or sheet of film exposed count seems lost today.. due to the non-cost of digital image making.. but appears to have been some what re-discovered by folks new to film image making.

Take the time to read the complete Sinar Info# 31 on Contrast Control as it directly applies to this specific discussion and speaks directly to the belief bracketing exposures is needed.. the .jpg versions to follow..
https://www.pacificrimcamera.com/rl/01388/01388.pdf

Discussion by Olympus Lifescience on film exposure.. info applies here.
https://www.olympus-lifescience.com/.../filmexposure/

As for, "Weeks often months can go by before I shoot a shot.".. Non-option for photographers that make images to put food on their table, roof over their head and meeting the demands of daily life and living... This is one of the differences between some of the very best artistic commercial photographers back in the day -vs- hobbyist or artist wanna be..


Bernice

Bernice. That's great for work in a studio with controlled light or at a photo shoot in midday light where you have loads of equipment and helpers. But for the average, non-pro (even pro) photographer shooting landscapes quickly during "magic hour" with fast-changing light that's often hard to assess, bracketing works and could save the time spent in the field. It may save the photo shoot. It's not a contest. Bracketing is another tool in the toolbox. You use it when you need to use it.

[LabRat]

Yes, there are developers that can cut or bump-up the EI of your film, but the majority are formulated to give about box speed to the film for a given developing time, but there are outliers... Your testing for speed involves looking at density that starts building in the shadows in the clear areas after development (where base fog starts building density)...

Correlating this with metering is the key... As a general metering plan, use a narrow ° spotmeter where you can measure shadow & highlight values... The meter measures spots as middle grey (zone V) values, but if you measure the middle grey brightness first, you will find in practice that most common scenes, highlight areas you are trying to hold detail in are usually about 1 f stop above the middle grey reading in normal scenes, but shadow regions have 2 stops under the middle grey reading that will safely record lower value detail, but 3 stops below will start to record detail, but only rough dark forms... Your developing time test involves not developing too long where the highlights start to block up and extends the printable range of the highlights... This is about the practical "dynamic range" you get with standard B/W developer development... You find much indoor/outdoor scenes will work if your exposure is placed between these readings, and you get a good rough exposure for your simplified film testing... Together, these work well until you get into advanced calibration tests, but above works great!!!

Good luck!!!

Steve K

[Drew Wiley]

Well ... not exactly bracketing to accommodate potential exposure errors... but there is that "magic hour" drama which Alan referred to, when the light is constantly changing, and there is likely going to be not just one "best" image, but potentially numerous as the hues change in the sky. I have often worked with that "hour" and two in the mountains, both dawn and dusk. But sometimes the shifts are so rapid in the tropics as the sun sets that it's hard to re-meter fast enough to keep up with sheet film exposures. The key is practice and experience; but that might be hard to achieve on a one-time opportunity.

Black and white film can be more forgiving in that respect, since hue reproduction isn't involved. But other than the shifting sequence style of photography just described, I can't even remember the last time I ever bracketed per se in the mountains with either color or black and white film. I do customarily do bracket tests on roll film for any new film I'm not already familiar with, and under anticipated field conditions as well as analytically using standardized targets, including with the potential filters I might use too. My early learning curve, however, was more of a Clint Eastwood "Hang em High" experience, yet in the shoot myself in the foot mode. One learns fast when it hurts.

[neil poulsen]

For standard black and white film like Tri-X, HP5, or TMax 400, you're pretty safe in using a speed that's half the manufacture's recommended ASA. (e.g., 200ASA for 400ASA film, 60ASA for 125ASA film, etc.) That's assuming that you expose for the shadows and develop for the highlights.

But without a darkroom, I'd suggest just using the manufacture's recommended ASA, or a little less. But, don't expect the same quality of results

For color, I would use the manufacture's recommended or a little less. (e.g. 126ASA instead of 160ASA, etc.)

[Drew Wiley]

I wouldn't call overexposing Tmax a full stop safe at all unless it's a mild contrast subject to begin with, or an odd developer. With more conventional films with a longer toe like FP4 or HP5 or Tri-X, cutting the box speed in half often does work decently, depending.

[Alan Klein]

Well ... not exactly bracketing to accommodate potential exposure errors... but there is that "magic hour" drama which Alan referred to, when the light is constantly changing, and there is likely going to be not just one "best" image, but potentially numerous as the hues change in the sky. I have often worked with that "hour" and two in the mountains, both dawn and dusk. But sometimes the shifts are so rapid in the tropics as the sun sets that it's hard to re-meter fast enough to keep up with sheet film exposures. The key is practice and experience; but that might be hard to achieve on a one-time opportunity.

Black and white film can be more forgiving in that respect, since hue reproduction isn't involved. But other than the shifting sequence style of photography just described, I can't even remember the last time I ever bracketed per se in the mountains with either color or black and white film. I do customarily do bracket tests on roll film for any new film I'm not already familiar with, and under anticipated field conditions as well as analytically using standardized targets, including with the potential filters I might use too. My early learning curve, however, was more of a Clint Eastwood "Hang em High" experience, yet in the shoot myself in the foot mode. One learns fast when it hurts.

Not everyone shoots as much as you do. So if bracketing allows less experienced photographers to capture the right exposure under especially difficult lighting conditions, and go home bagging the game, I don't see why they owe anyone an apology. Why turn it into an ego trip?

[Drew Wiley]

How much do I shoot, Alan? I've come back from strenuous ten day treks with only two chromes exposed, plus a few black and white sheets. There's no ego trip involved. Conserving film was just a fact of life until Quickload and Readyload sleeves finally got the bugs worked out. 8x10 is an even more restrictive format. And only a small percent of shots ever get printed anyway. But if a shot doesn't at least seem worthy of printing some day, I simply don't press the shutter. That's how I approach it. Even Babe Ruth struck out more often than he hit a home run. But it's helpful to increase the odds in any manner you can; and when that is itself restricted by the parameter of tightly rationing sheet film for sake of the duration of a trip, so be it.

If there's any doubt in my mind, taking roll film backs instead makes more sense, with perhaps just a few full-sized 4x5 filmholders along too. My era of 85 lb packs for two weeks at a time is over anyway. The last three long hikes I took involved roll film, either 6x9 backs for my little 4x5 Ebony, or an actual 6X9 rangefinder camera. And it won't be long till Ill need help with some of my load. The clock is tickin'.

[Alan Klein]

How much do I shoot, Alan? I've come back from strenuous ten day treks with only two chromes exposed, plus a few black and white sheets. There's no ego trip involved. Conserving film was just a fact of life until Quickload and Readyload sleeves finally got the bugs worked out. 8x10 is an even more restrictive format. And only a small percent of shots ever get printed anyway. But if a shot doesn't seem worthy of printing to begin with, I simply don't press the shutter. That's how I approach it. Even Babe Ruth struck out more often than he hit a home run. But it's helpful to increase the odds in any manner you can; and when that is itself restricted by the parameter of tightly rationing sheet film for sake of the duration of a trip, so be it. If there's any doubt in my mind, taking roll film backs instead makes more sense, with perhaps just a few full-sized 4x5 filmholders along too.

Well, as I said in an earlier post, I always bracketed with roll film. I'ts just so easy and convenient and cheap. I agree now that I started 4x5 2 1/2 years ago that I don't bracket except in tough lighting conditions. I just think it's smarter for me to admit I'm not perfect and take two shots than insist I am and go home with one shot that's too dark.