How many of you have done this to find your "personal film speed"?

[rpavich]

Well...another eye opener for me. There was a discussion about "proper" proof sheets here a short time ago where someone suggested that I print my proof sheet where the exposure of the clear film edge just catches up with the sprocket holes...in other words...when true black is achieved but no more.

Needless to say I found that I underexpose quite a lot but never really realized it because of two things:

1.) When scanning negs the scanner optimizes the density of each so that it appears that I've been super consistent in my exposures.

2.) When making my contact sheets I have been printing so that they all looked "pretty good" without regard to how the edges looked.

So, I read this article about finding your personal film speed and up until now I've just been over exposing and it's been working pretty well, my negs look much better but still, I was thinking about trying this little exercise to find out just how much I have to offset the ISO to get properly exposed negs based on my film, developing, and other variables.

My question to you folks is; have any of you done this? Can you comment on your experience with it?

I've read it a few times trying to solidify in my mind what has to happen how to get it done. It seems complicated on the surface so I'm trying to grasp it before I dive in and make a huge mistake.

If anyone has anything to comment that would make it easier to internalize, then by all means, please jump in.

Here is part one of the article and part two below.

http://www.halfhill.com/speed1.html


http://www.halfhill.com/speed2.html

 

[Luis-F-S]

Fred Picker 101. Read the Zone VI Workshop. Under $4 shipped on the Bay.

Oliver Gaglianni taught a much more detailed procedure to determine film speed & developing time for Normal, N-1, N+1 & N+2 but it's way too detailed to get into here.

 

[rpavich]

Fred Picker 101. Read the Zone VI Workshop. Under $4 shipped on the Bay.

Oliver Gaglianni taught a much more detailed procedure to determine film speed & developing time for Normal, N-1, N+1 & N+2 but it's way too detailed to get into here.

Cool...I'll check it out. Thanks!

 

[Doremus Scudder]

I use this method to determine my personal E.I. and development times. It's pretty simple but (and there are a few "buts") you need to do the assessment correctly. First, since this method is paper-dependent, you need to choose a "default" printing paper and grade. Not only that, but you need a default print developer and processing method. You should choose these with the idea that there will be variation and you just need to get your exposure in the ballpark.

Then, you need to decide on the lighting you want to display your prints under, because that will determine when your eye sees the same black for the clear film edge and the paper black. Brighter light = slower E.I. Assessing under dim light will cause you to underexpose your negatives... So, since the object of determining your personal E.I. in the first place is to make sure you don't underexpose, evaluate under a fairly bright display lighting, but don't overdo it, or you'll end up overexposing. FWIW my personal E.I. for all of the films I use is 1/3-2/3 stop slower than box speed, not more. And, I could probably get away with box speed if I were really careful when exposing. Part of the Zone System is a built-in safety factor of overexposure of about 1/3-stop. Since I shoot LF, I can easily live with that. If I were doing this for 35mm like you are, I'd probably err on the side of getting closer to box speed if there were any discrepancies.

Okay, so here you are with your "proper proof." Once you have decided and standardized, you can use your proof sheet to help you choose paper grade/filtration and to spot problems. I proof everything and adjust my personal E.I. and developing times depending on the results I get over time from them. Keeping good notes and being able to go back over a year or two's proof sheets will point out trends that often need correcting. This latter is the most useful part of doing all the calibration in the first place.

Best,

Doremus

 

[Sirius Glass]

Keep life simple:

• Shoot at box speed
• Do not include the sky in the reflective light meter reading
• If the composition is either all white [very light] or all black [very dark] use and incidence meter
• Tell the testinestas to shove it

 

[rpavich]

Well..it's settled.

It works.

It's myth

Don't do it.

do it.

Oh well...I'll check it out and see if it has any effect on my consistency and exposure. It will be fun.

 

[Dali]

On this matter, I listen to David Vestal... and his tests matched with the experience.

 

[Sirius Glass]

Well..it's settled.

It works.

It's myth

Don't do it.

do it.

Oh well...I'll check it out and see if it has any effect on my consistency and exposure. It will be fun.

And if you follow this advice and are not satisfied double your money back.

Haven't we had enough of these threads???

 

[Ken Nadvornick]

Well..it's settled.

It works.
It's myth
Don't do it.
do it.

One of the members here used to have a signature line that read: "Go not to the elves for counsel, for they will say both no and yes."

(Frodo to Gildor...)



Ken

 

[John Koehrer]

On this matter, I listen to David Vestal... and his tests matched with the experience.

You too, Huh?

 

[ic-racer]

Keep it simple. Expose negatives 1/2 box speed. Develop negatives so prints look good on #2 and use multicontrast paper.

 

[Sirius Glass]

Keep it simple. Expose negatives at box speed. Develop negatives so prints look good on #2 and use multicontrast paper. Negative film has more than enough latitude so that one does not need to play the testinesta games.

The film manufacturers know more about their products than you ever will. Get over it.

Fifty or sixty years ago, the Zonista testing may have been useful.

 

[bdial]

Keep it simple;
Buy the copy of Zone VI Workshop, read it, then test (or not) and make your own decisions on what works for you.
Using Picker's "Proper Proof" method and testing for personal film speed works, so do lots of other schemes. I tend to expose at box speed, but I've also made tests to determine that it's valid for the films and developer I use.

Also, it's probably worth pointing out that scanning negs for inkjet output is different than printing them on silver gelatin paper. In particular, negatives that would be considered thin and underexposed for silver printing are better for scanning.

 

[David Brown]

The film manufacturers know more about their products than you ever will. Get over it.

I'm convinced that "personal" film speed is nothing more than compensating for poor metering and/or developing technique ...

 

[Ken Nadvornick]

You know, there are valid reasons to test for personalized parameters. Including film speeds.

Everyone here wants to just blindly accept the manufacturer's determinations. But that is only valid if each and every other contributing variable in your own overall system also exactly matches that manufacturer's testing regime. And that is virtually never the case.

Say, for example, that you have a camera whose shutter is old and slow. You love that camera, and want to continue using it. But you don't have the money to spend on an expensive CLA to bring the shutter back into factory spec.

What to do?

How about running an EI test for your favorite film to determine just what correction to the manufacturer's ISO rating you need to apply to get correctly exposed film for that particular camera system? Your film EIs will rise as your shutter slows.

The CLA might cost you a couple hundred dollars and six weeks. The film test might cost you a couple dollars and 60 minutes. And after the fact in both cases the film will be correctly exposed.



Ken

 

[Sirius Glass]

I'm convinced that "personal" film speed is nothing more than compensating for poor metering and/or developing technique ...

You broke the code. Personal film speed is an excuse for poor metering technique and improper equipment calibration, but it is hard to image that screwing with the personal film speed will compensate for taking light readings of the sky and a shutter which is slow for one or two speeds.

 

[craigclu]

Barry Thornton's thoughts on this are worth contemplating....

Dead Link Removed

 

[David Allen]

You know, there are valid reasons to test for personalized parameters. Including film speeds.

Everyone here wants to just blindly accept the manufacturer's determinations. But that is only valid if each and every other contributing variable in your own overall system also exactly matches that manufacturer's testing regime. And that is virtually never the case.

Say, for example, that you have a camera whose shutter is old and slow. You love that camera, and want to continue using it. But you don't have the money to spend on an expensive CLA to bring the shutter back into factory spec.

What to do?

How about running an EI test for your favorite film to determine just what correction to the manufacturer's ISO rating you need to apply to get correctly exposed film for that particular camera system? Your film EIs will rise as your shutter slows.

The CLA might cost you a couple hundred dollars and six weeks. The film test might cost you a couple dollars and 60 minutes. And after the fact in both cases the film will be correctly exposed.



Ken

+1

Hi there,

The system described reads rather complicated but, as I know from experience, trying to write a simple straightforward explanation of a simple test is a challenge and writing all the steps down makes it look really complicated. The system I teach can be found here:

(there was a url link here which no longer exists)

Please refer to my post no #3

The problem with such threads as these are they quickly descend into two camps:

The so called ‘testinestas’ who try to explain why they undertake such a test and the reasons behind this

and

the people who rubbish people who undertake such tests and make comments such as “Tell the testinestas to shove it”

Now none of this is much help to someone who is seeking advice - especially when the person asking the question has no idea of what quality standards are pursued by the people posting.

I am in the testing camp for the following reasons:

One
Having taught hundreds of students and tested their equipment, it is a fact that differing equipment (even from the same manufacturer) can deliver varying results in terms of exposure and contrast. For example, a 1950’s Rollei twin-lens reflex with simply coated lens demonstrates more flare than a 1980s Nikon with super-multicoated lens. The result is that Tri-X in the Rollei mostly delivers an EI of 400 and needs longer development than Tri-X in the Nikon which mostly delivers an EI of 200 (please note that these are averages and I have had students with the same camera make and lens having differing EIs).

Two (and for me the most important as it takes novices to a point where they can achieve correctly exposed negatives every time)
Using this testing method and the related exposure method enables a beginner to go from woefully inaccurate and inconsistent results to well exposed and developed images in a matter of a few hours. If you have done the tests in the article that the OP posted as a link to or if you follow Fred Picker’s system or my methodology, you will have pinned down necessary exposure to achieve shadow detail and placing highlight detail and the appropriate development time.

Once you have done the tests (note that I do not recommend constant tests of materials but rather doing it once and then sticking to the methodology) all the beginner has to remember is:

• To meter the darkest shadow area where they wish to retain detail and adjust the meter’s recommendation by closing down two stops or increasing the shutter speed by two stops.
• To meter the brightest highlight area where they wish to retain detail (excluding the sky and on a dull day this may in fact be a light grey wall) and adjust the meter’s recommendation by opening up three stops or reducing the shutter speed by three stops.

That is it, no need for years of wasting film and time trying to build experience of how to compensate for different lighting conditions. It also short circuits many of the suggestions given as to why people are ‘wrong’ to test for a personal EI, such as:

“they meter too much sky and have not learned to take a light reading correctly”
If you follow any version of the testing strategy, you will never meter the sky and will require 0 years experience of how to meter correctly because you either meter the important shadow area or the important highlight area. Absolutely no need to spend years building up knowledge and experience.

“the meter is out of calibration and needs adjustment”
It is really not necessary for a meter to be calibrated correctly. What is of fundamental importance is that it is CONSISTENT. Any inaccuracy will be compensated for by the real world testing method.

“the camera/lens is out of calibration and needs a CLA”
It is really not necessary for a camera/lens to be calibrated correctly. What is of fundamental importance is that it is CONSISTENT. Any inaccuracy will be compensated for by the real world testing method and how many people earn enough to pay for a CLA on a good quality camera?

If you undertake practical tests using your equipment none of the above matters because it will all be automatically compensated for during the tests. Even if your camera is working as per blueprint (highly unlikely given required production tolerances) it cannot be assumed that the box speed will suit your equipment, exposure and development technique.

Bests,

David.
www.dsallen.de

 

[Doremus Scudder]

Personal film speeds are largely myth.

Also, "minimum time to maximum black" is a fairly unreliable method, and of questionable utility.

Hi Michael,

I've used the Zone System calibration method outlined in "The New Zone System Manual" by Minor White, R. Zakia and P. Lorenz for years. It is predicated on finding "minimum time to (useable) maximum black" and has worked well for me. While I realize that this is not a quantifiable approach with a lot of variables and the need for experienced and intelligent interpretation (it took me a while to decide which "black" was the one I needed to work to, for example), I have found the method to be of more than "questionable utility." Similarly, the "proper proof" works for me as a quick and easy check on my overall system (exposure, development, equipment failures, operator errors, etc.) and allows me to adjust my processing without going through a lot of testing (e.g., if N+1 is consistently to flat, I'll increase development for that and keep an eye on it in the next proofs to see how I'm doing).

So, I'm interested in your take on all this and if you would mind elaborating on your comments above. Is the approach outlined in "The New Zone System Manual" hopelessly outdated? Or were the authors just wrong?

I'm also curious as to why you think so many of the Zone System practitioners (and others as well) advocate finding a personal E.I. I've found it useful, even though my speeds don't deviate much from "box speed" at all. For those that use exotic developers, etc. I would think nailing down E.I. would be the primary tool for avoiding underexposure.

Sure, if you use Kodak film and developers and follow their recommendations you'll likely be just fine, but even Kodak recommends different E.Is. for their films in different developers...

Not trying to be flippant, but genuinely curious as to your opinions here.

Best,

Doremus

 

[Tony Egan]

"Finding your personal EI" sold a few photography magazines over the years but I think it's mostly nonsense and a misguided term to have coined. As if those noble silver metals somehow respond to your personal aura or body temperature or temperament. "Purposeful EI" makes more sense because you are not always taking exactly the same photo in the same lighting conditions with the same camera and lens and printing under the same enlarger etc. Exposure is best determined by the purpose or intent, not the identity of the person. Always erring on the side of a bit more exposure is about as personal as it gets for me when shooting B&W film for standard enlarger printing on silver gelatin paper.

Having said this, the only value of "personal EI" articles is to make people think about their end-to-end practice, the enlargers they use, papers and developers, alternative process adjustments etc. and to understand there is no "right" answer for any situation.

 

[Arctic amateur]

[deleted, already mentioned]

 

[RalphLambrecht]

Well...another eye opener for me. There was a discussion about "proper" proof sheets here a short time ago where someone suggested that I print my proof sheet where the exposure of the clear film edge just catches up with the sprocket holes...in other words...when true black is achieved but no more.

Needless to say I found that I underexpose quite a lot but never really realized it because of two things:

1.) When scanning negs the scanner optimizes the density of each so that it appears that I've been super consistent in my exposures.

2.) When making my contact sheets I have been printing so that they all looked "pretty good" without regard to how the edges looked.

So, I read this article about finding your personal film speed and up until now I've just been over exposing and it's been working pretty well, my negs look much better but still, I was thinking about trying this little exercise to find out just how much I have to offset the ISO to get properly exposed negs based on my film, developing, and other variables.

My question to you folks is; have any of you done this? Can you comment on your experience with it?

I've read it a few times trying to solidify in my mind what has to happen how to get it done. It seems complicated on the surface so I'm trying to grasp it before I dive in and make a huge mistake.

If anyone has anything to comment that would make it easier to internalize, then by all means, please jump in.

Here is part one of the article and part two below.

http://www.halfhill.com/speed1.html
Yes, and I typically take 2/3 off the box speed to get closer to a decent exposure for the shadows

http://www.halfhill.com/speed2.html

 

[esearing]

interesting read but before you can do your "personal Film Speed" you might want to nail your personal development time with your personal developer. Seems a lot of old pros use 20%-30% less time than manufacturer recommended except for 2 bath developers. Develop fully exposed pieces of film to determine where the density begins to visibly change from the dark grey to slightly less dark grey. Some like to pick the time that allows them to read news print through the dry negative. You may want to test different dilutions here.

After that you need to test your shutter(s) at all speeds . 35mm will generally be off about the same at all speeds whereas the shutters on my 4x5 lenses vary greatly from marked speed at slow vs fast and vary for each lens. I run my test twice a year and carry 3x5 cards with the info.

Now do your film EI tests

Followed by
Color filter/ ND+reciprocity tests for B&W film
Test extended and contracted development times for different SBR scenes to determine contrast differences.
Paper tests (max black min time, min time to fogging, safelight fogging, room light leak fogging, extended development, new bulb/old bulb)
Paper Filter grade tests (and split grade tests)
bleaching and toning tests for archival permanence vs purposeful color shift
film scanning density tests with your scanner

Also take really good notes in the field to figure out how the scene brightness and range affects your personal interpretation of what you thought you saw versus what appears later on film/paper. The glass+focus-screen+eyes+brain can vary from reality, the film records reflected light at certain wavelengths.
Use a spot meter initially or if using incident meter get to know EV values. Get to know glare and reflections.

All that should get you creating a basically well exposed negative to work with most of the time.

OR
you can bracket your shots (assuming subject allows) and try to be consistent in processing. Hopefully chemistry is consistent over time.
Don't be afraid of mistakes and have fun experimenting.

 

[ic-racer]

Exposure index is set before film development time determination.

Do the tests, if you get box speed, then use that. Otherwise live in the dark; ignore 70 years of research on film exposure determination. Recommendations on on these forums based on hearsay or "I read it on the internet" should be removed by the moderators.

Manufacturers of film rate the film. They can't test your equipment and don't know how you use the film. They don't do your work for you.

 

[Jim Noel]

I test ever new batch of film for the correct personal exposure index, (EI). This is not as crazy as it sounds since I normally buy film in large batches of 200-300 sheets.