Formapan 200 - Speed rating and Reciprocity

[Muzz]

For reasons of economy I am starting out with Formapan 200 (5x4). The product tech data gives rather hazy info around Reciprocity compensation. Does anyone out there have practical, rather than theoretical knowledge of the compensation required as exposure increases. Also there are many suggestions around rating it at 100, I don't want to overly extend the thread but are there any further comments. I am going to use Bellini Eco Range developer.

 

[Ian Grant]

I've been using Fomapan 200 for around 15 or 16 years, I did tests an found it best at 100 ISO, development time is around 25% less than the other films I use.

This was my comments on reciprocity 12 years ago: t 1 second it only only needed around half a stop (recommendation is 1.5 stops) and at lower light levels 10 seconds it was about a stop (not the 3 stops recommended). These test were made in poor daylight 1 second @ f8 100 EI and very low interior lighting 10 seconds @ f8. These are the conditions the film will be used in.

That was based on actual test shots in low daylight. early twylight. If it's indoors with articial light rember ISO speeds are lower in Tugsten light, that includes warm hite equivalents.

Ian

 

[thronobulax]

I have done densiometric testing on a range of films including Kodak, Ilford, Arista, Efke, and Agfa and with a number of different developers in some cases. Without exception, when agitating normally as per the developer recommendations and assuming your thermometer, meter, and shutters are reasonably correct, every single film I have tested showed an effective ASA of 1/2 the box rated speed.

I therefore no longer test. I just start out at 1/2 box speed and reduce development about 20% from recommended at time/temp and get strong negatives every time.

There is, of course, an exception to this. If you do Extreme Miminal Agitation or Semistand, you'll get essentially box speed. The cost of doing this is the fiddling one has to endure to get low agitation techniques to work, and of course, the much longer development times.

 

[Muzz]

I've been using Fomapan 200 for around 15 or 16 years, I did tests an found it best at 100 ISO, development time is around 25% less than the other films I use.

This was my comments on reciprocity 12 years ago: t 1 second it only only needed around half a stop (recommendation is 1.5 stops) and at lower light levels 10 seconds it was about a stop (not the 3 stops recommended). These test were made in poor daylight 1 second @ f8 100 EI and very low interior lighting 10 seconds @ f8. These are the conditions the film will be used in.

That was based on actual test shots in low daylight. early twylight. If it's indoors with articial light rember ISO speeds are lower in Tugsten light, that includes warm hite equivalents.

Ian

Thanks for your reply Ian - Your reciprocity recommendations are very different from anything else that's posted but guess that is due to down rating the film plus real time rather than theoretical curve extrapolation. Do you have interim results - for example are you suggesting 0.5 increase from 1 sec to 10 sec and then 1 stop from 10 sec till ........ where?

 

[Muzz]

I have done densiometric testing on a range of films including Kodak, Ilford, Arista, Efke, and Agfa and with a number of different developers in some cases. Without exception, when agitating normally as per the developer recommendations and assuming your thermometer, meter, and shutters are reasonably correct, every single film I have tested showed an effective ASA of 1/2 the box rated speed.

I therefore no longer test. I just start out at 1/2 box speed and reduce development about 20% from recommended at time/temp and get strong negatives every time.

There is, of course, an exception to this. If you do Extreme Miminal Agitation or Semistand, you'll get essentially box speed. The cost of doing this is the fiddling one has to endure to get low agitation techniques to work, and of course, the much longer development times.

Thanks - I will definitely rate the film at half box speed.

 

[David M]

It seems that most people find that half box speed for exposure and 20% less bottle time for development works reasonably well. Most Zone testing seems to converge to the much same end-point, although naturally there willl be variations due to personal preferences, local conditions, individual equipment, subject matter and convenience.
Extreme non-standard development is another matter, which I’m unqualified to deal with. It does seem to provide unparalleled opportunities for debate.

 

[Marley]

I think the caveat on all of this is is that we all have our own ways of metering, our own development disciplines, and we are in the main using lenses with leaf shutters that may well never have been perfectly accurate out of the box. One person may be muttering 'higgledy piggledy one, higgledy piggledy two ...' and another may be using a stopwatch or an app for timed exposure. Also, another person's 'perfect neg' may not be to another person's taste.
The real point here is that film 'speed' is only ever a guide ...

 

[Ian Grant]

Thanks for your reply Ian - Your reciprocity recommendations are very different from anything else that's posted but guess that is due to down rating the film plus real time rather than theoretical curve extrapolation. Do you have interim results - for example are you suggesting 0.5 increase from 1 sec to 10 sec and then 1 stop from 10 sec till ........ where?

I didn't do any interim tests, but would increase exposure slightly between 2 seconds and 9 seconds, and open up more than a sop past 10 seconds.

I'm sure that rating at half box speed is one reason why I find in practice reciprocity isn't as bad as Foma's own recommendations, however over the years it's rare I've needed to worry about reciprocity.

Ian

 

[David M]

You are right.
We cheerfully say “film speed” but what we need to know in practice is what number to set on our own meter. Although some may find it satisfying to measure negative densities, what we really need to know is what will yield a satisfactory print within our own practice. Film speed proper is something different; it is a matter for the manufacturer.
For example, the desired negative density may occur in a part of the curve that’s so shallow that no useful detail can be retrieved. Another person may prefer an unusually dense negative, because they like the tonal rendering or because it makes extensive dodging and burning easier. Some might be following, unquestioningly, the advice of a revered mentor. And everybody’s metering method is different…

 

[thronobulax]

Extreme non-standard development is another matter, which I’m unqualified to deal with. It does seem to provide unparalleled opportunities for debate.

THAT is the understatement of the year. When I first wrote up my findings on low agitation techniques, I thought I'd written an interesting, fairly balanced report on my experience. Most people were either really interested or didn't care. But there were a few folk who excoriated me for my photographic sins. One guy - a former Kodak engineer - kept telling me that Kodak never designed their films for low/no agitation. I replied "Yes, and you're not supposed to blow out the heads on your Ford to develop an extra 30 HP either." Another guy kept questioning my methods and results, and when I showed both to him thereby validating my claims, he still didn't believe it. Go figure.

Our personal biases are the biggest impediments to learning. Being willing to suffer through the learning curve of low/no agitation has materially improved my work and opened the door to other interesting exploration like "How old can film be and still give me quality results?" (Hint: I got good results with film expired in 1961!) ALL of this came from the fact that someone on the pure-silver list pointed me at Pyrocat-HD and then many of you here helped me master that in its convention use.

SHAMELESS SELF PROMOTION FOLLOWS: For those who've not seen my report on all this, now updated several times:

tundra/Stand-Development

gitbucket.tundraware.com

It is NOT for everyone nor every subject, but it's a great arrow to have in your quiver.

 

[thronobulax]

Thanks - I will definitely rate the film at half box speed.

Just be aware that doing so also requires you decrease development about 20%.

Also note that these guidelines assume you have decently accurate thermometers, lightmeters, and shutters. Although not absolutely required, for consistency's sake, I recommend using distilled water for the developer.

 

[thronobulax]

I think the caveat on all of this is is that we all have our own ways of metering, our own development disciplines, and we are in the main using lenses with leaf shutters that may well never have been perfectly accurate out of the box. One person may be muttering 'higgledy piggledy one, higgledy piggledy two ...' and another may be using a stopwatch or an app for timed exposure. Also, another person's 'perfect neg' may not be to another person's taste.
The real point here is that film 'speed' is only ever a guide ...

Very much the case. Up until the early 1960s, film was rated at about 1/2 the box ASA you see today. This was the nominal ASA required to make a good picture. Then the standard changed to what is the minimum exposure required to show an image (this is a vast oversimplification but good enough for our purposes). ASA today should therefore be understood much like new vehicle mileage estimates - a good relative gauge, but not correct for making real pictures.

The purpose of Zone testing above all things is to achieve consistency not absolute lab accuracy. As you say, shutters vary, as do light meters, water content, thermometers ... The testing helps one find their "personal ASA" with their equipment and environment. But, that said, in my environment where all these things are checked and known (including shutter speed), I have found consistently that 1/2 the box ASA at 20% less development gives "normal" negatives the exact right processing.

Moreover, shutters are normally slow if they are off, and this has the effect of increasing exposure. In almost all cases this is a net good thing because it is easier to print a slightly overexposed negative. You cannot print what does not exist in an underexposed negative. There are exceptions - low agitation development hates vastly overexposed negs, for example. But, in the general case, shutter drag isn't a horrible thing.

 

[thronobulax]

You are right.
We cheerfully say “film speed” but what we need to know in practice is what number to set on our own meter. Although some may find it satisfying to measure negative densities, what we really need to know is what will yield a satisfactory print within our own practice. Film speed proper is something different; it is a matter for the manufacturer.
For example, the desired negative density may occur in a part of the curve that’s so shallow that no useful detail can be retrieved. Another person may prefer an unusually dense negative, because they like the tonal rendering or because it makes extensive dodging and burning easier. Some might be following, unquestioningly, the advice of a revered mentor. And everybody’s metering method is different…

Another thing often forgotten is how the negative will be reproduced. Printing on a condenser head, a diffusion head, or digital scanning will all require different kinds of exposure/development practices to manage the Gamma of the H/D curve and control the shape at the top- and bottom densities.

 

[David M]

Your reply prompted a thought.
These techniques seem to depend on controlling the film's access to the active chemicals. And you have a small problem with supporting the film.
What if there were a setup, where the film was held between two sheets of smooth waterproof material and the developer held inside the sandwich by surface tension? Rather like wet-scanning. Agitation would be by peeling back one layer and flooding the neg, rather as a wet-plate is coated, followed by replacing the top slice of the sandwich.
If the sheets were transparent, then development by (intermittent) inspection would be quite easy.
This has had very nearly five minutes' thought, so it should be easy to spot the errors and misconceptions.

 

[thronobulax]

Your reply prompted a thought.
These techniques seem to depend on controlling the film's access to the active chemicals. And you have a small problem with supporting the film.
What if there were a setup, where the film was held between two sheets of smooth waterproof material and the developer held inside the sandwich by surface tension? Rather like wet-scanning. Agitation would be by peeling back one layer and flooding the neg, rather as a wet-plate is coated, followed by replacing the top slice of the sandwich.
If the sheets were transparent, then development by (intermittent) inspection would be quite easy.
This has had very nearly five minutes' thought, so it should be easy to spot the errors and misconceptions.

This would almost certainly cause the bromides to be trapped against the negative and pretty much ruin it. The perfect suspension for low agitation would be one it which there was NO suspension - it just floated in the developer without moving. I do not currently have a design for an anti-gravity machine which might accomplish this

However, a slightly related method is used by Steve Sherman (and others) wherein the negative is held minimally by curling it into the interior of a piece of PVC tubing. Steve has YouTube videos on how this is done.

 

[David M]

Ah well, bang goes my dream of millions!
I had, however thought that retaining bromides at the light/dark boundary played a part in forming the Mackie line.

I've seen videos of tube development. The "Taco" method seems similar in holding the film.

Keep working on that anti-gravity machine.

 

[Muzz]

I suppose I will just have to bite the bullet, manage as many variables as possible, do some tests and see what develops!

 

[David M]

Tests is the usual path. After that, you can be as simple or as complex as you please. Plenty of guidance on Zone testing on the web, or you could read (eg) John Blakemore’s book. There are others.

 

[thronobulax]

I stopped formal measurement once I realized that all films more or less showed up about the same sensiometrically. I did test Efke PL100 because it is such a different sort of film. Imagine my shock when I discovered it to measure at ASA 100 or "box speed". Then someone here helpfully pointed out that Efke's rated ASA was for tungsten not daylight and that the former ASA is actually 200 ... hence the film measured at 1/2 daylight box speed as normal. Subsequent low agitation development confirmed full speed at 200.

While I stopped formal measurement for the most part, I've never stopped "testing". I keep considerable documentation of each roll/sheet I shoot and inspect the results on a light table, and of course, in the final print. For example, just today, I shot some 3x2 Efke at ASA 200 with the intent of trying something new: A hybrid of Semistand and EMA. I've diluted the developer more than usual (1.5:1:300), but will give the film three equally spaced agitations (after initial) in the hour it is standing. I am trying to see if I can accentuate edge effects whilst preserving the full benefits of Semistand.

I'd much rather make "real" images as a platform for testing rather than just doing pure testing. It's far more motivating. I once heard the late great jazz guitarist Joe Pass in a Master Class say to a student, Do you play your scales every day? The student nodded. Joe smiled and said, Don't play scales, play tunes, you'll meet more girls that way. Indeed and amen.

 

[Marley]

When I was in my twenties ... and just getting going properly as a freelance photographer we used to have a bloke called 'Big John' who used to come into my local pub. He was an enthusiastic amateur photographer and used to excitedly zero in on me for photo conversations over a pint. John was in his early forties had a well paid enginearing job and still lived with his mum and dad - so had a truck load of disposable income. Every week it seemed he'd bring in another sparkling new bit of photographic kit - he was into the Contax/Yashica 35mm system and I was seriously envious of the high quality glass he was buying. He used to bring in lens test target prints from his top notch optics, and endless shots of a view of his local church that he used as a 'practical test' for his developer experiments. I never saw a proper picture that poor old Big John took ... I several times invited him to go on photo walks with me ... he always seemed scared to.

when @thronobulax says:

'I'd much rather make "real" images as a platform for testing rather than just doing pure testing. It's far more motivating. I once heard the late great jazz guitarist Joe Pass in a Master Class say to a student, Do you play your scales every day? The student nodded. Joe smiled and said, Don't play scales, play tunes, you'll meet more girls that way. Indeed and amen'.

Amen indeed!
It's an amazing world full of scenes that can stir your emotions - get out into it and make beauty.