The ASA speed change probably didn’t change what people were doing

[Bill Burk]

I took an old book from my shelf today, an Edwal Laboratories booklet on fine grain developing from 1946.

In Edwal 10 and Edwal 12, for daylight, 35mm cartridge Panatomic-X and Plus-X they gave a Scheiner rating and the next page had a conversion table that included Weston speeds.

They were recommending 32 and 125

 

[focus_on_infinity]

So, if I understand you, what you're suggesting is that at least some people probably weren't looking at ASA before the change, but at a metric that corresponded with the post-change ASA rating. Is that correct?

 

[138S]

Bill, IMO we have to consider two diffrent situations...

a) Consumers mostly obeyed and started to expose the half since 1960. This was benefical for them.

b) Pros and proficient artists that had their workflow well optimized yet continued doing the same. One is not to change a well optimized system because of something stamped on a box...

 

[Juan Valdenebro]

Maybe despite the safety factor (a stop) people back then used to test materials too...

 

[Bill Burk]

@focus_on_infinity Right!

I wanted a pre-1960 reference for film speeds and I sure got it in “Modern Developing Methods for prints and fine grain negatives” The Edwal Laboratories, Inc. technical staff under the direction of Edmund W. Lowe, Ph.D.

Here is an example paragraph that hints at what’s inside... at first glance there are so many speed combinations that it might be confusing, but their advice fits the narrative.

 

[MattKing]

The vast majority of people who used film back before 1961 gave their film to their local drugstore or similar developing resource.
And most of that film came from something like a Brownie box camera.
The ASA standard prior to then reflected what the amateur market and the amateur photofinishing industry needed.
But by that time, box cameras and the other sorts of cameras used by the majority of the populace were improving, so it was time to reduce the safety factor.
People like Zone system practitioners use different measures for what constitutes film sensitivity ("speed") because they tend to have and use better equipment, and because they tend to use more controls in development and printing, than the amateur photographers and the photofinishers who gave them back their 3.5"x5" or similar sized snapshot prints.

 

[Bill Burk]

@michael_r Exactly and it says so in the literature.

And @MattKing that’s right too. The ordinary user had simple cameras, no meter and sent it in.

Edmund Waring Lowe was writing for the advanced amateur. Maybe there’s a bit of facilitating a search for the magic bullet. But it seems all worked out... If you want enlargements 6-10 diameters with full speed (the box speeds we have post-1964) use Edwal 10. If you want enlargements of 15-20 diameters use Edwal 12 at 1/2 (old) American speed. If you want enlargements 25 diameters or more (up to 60), use Edwal 20at the (old) American speed.

I have a hunch the company name is a bit of an anagram of his name.

 

[removed account4]

The ordinary user had simple cameras, no meter and sent it in

LOL
whenever I use film ( instead of paper in my cameras ) I never rate them at all
i put the camera at IDK f4 or 5.6 or wide open depending on the day and situation, and the shutter anywhere between 1/15S-1/125S depending
... and i just push the button, if it is a box camera i just load it and shoot. I usually develop it split in caffenol c and ansco 130 / dektol/d72 depending on what I have on hand... im glad im a throw-back to the olden days
speaking of throwing, I recently tossed my 3 year old caffneol. hadn't processed film for a year and 1/2 and it was getting kind of moldy

 

[Pentode]

speaking of throwing, I recently tossed my 3 year old caffneol. hadn't processed film for a year and 1/2 and it was getting kind of moldy

Oh, man.... that stuff smells revolting when it's fresh. I can't even begin to imagine it at 3 years old.

 

[Juan Valdenebro]

Part of the rationale for reducing the safety factor in the 1960 revision was that many photographers using smaller formats were already doing this in order to get slightly better image structure/quality.

Sure, Michael...
I didn't mean maybe that happenned... I meant maybe that's what Bill's implying, as another forum member was asking about the general subject... I find interesting we all no matter the decade or (almost) century have so many things in common because materials and light are basically the same... Old and new B&W photographers walk the same roads.

 

[Bill Burk]

Sure, Michael...
I didn't mean maybe that happenned... I meant maybe that's what Bill's implying, as another forum member was asking about the general subject...

I started by trying to find what film speed people used pre-1960. I knew some people considered the safety factor harmful. But I didn't have evidence of the film speeds people were using... I had no idea that in 1946 it was widely known you could get good results from Plus-X at 125.
This booklet I found isn't rare. 3rd editions are easy to come by, eBay has several and they are a pretty good deal.

 

[removed account4]

Oh, man.... that stuff smells revolting when it's fresh. I can't even begin to imagine it at 3 years old.

it wasn't too bad, but then again I don't even notice how bad it is when its fresh.

 

[Nodda Duma]

Bill, maybe I can provide some further insight into some of the early thinking that went into the safety factor, because I could see the appeal of adding a safety factor for my dry plates:

Many people who use my dry plates for the first time tend to underexpose because of the learning curve required for proper estimation of exposure. Once you become familiar with its nuances then that goes away.

As my emulsions replicate that of the dry plate era, I am sure beginners in the late 19th Century had the same learning curve. I could see the manufacturers of the time adding a 2x safety factor so they wouldn’t have to always be answering questions from beginners about why their first plates were underexposed....and yes the camera equipment played into this as well.

By the 1950s, it was harder for beginners to mess up due to better guidance/meters/equipment so the safety margin was no longer needed.

 

[138S]

Maybe despite the safety factor (a stop) people back then used to test materials too...

Yes... but consider that ZS, as defined by AA and Archer in 1940 had no safety factor, Z-I was nominally at -4 underexposure and density was just the speed point 0.1D+BF . In any case the it was a 0.3 stop safety factor because in 1940 speed point was at defined at -4.3 stops, 1/20 the exposure what meters aimed.

Of course, wisely, ZS instructs people to use an EI that will compensate any shift from workflow/materials. The core concept is just for kids: at speed point we start recording detail, we have near nothing under speed point. for us the photographers what the box says is relatively irrelevant, what we need to know is at what underexposure we have an spot in the Speed Point, which is not always evident as for example filtration has an interaction with fiml's spectral sensitivity. So testing just what it is necessary is good advice for film photography ! Some people test too much (me) some people do not test enough, that people that test what it is worth and spend the remaining time for creativity have an advantage, IMO.

 

[Nicholas Lindan]

Folks who go through an awful lot of testing to find their "personal film speed" invariably end up with a 2/3 to 1 stop reduction in speed along with a corresponding decrease in development time.

So, it may seem that the old speeds were the correct speeds.

 

[Bill Burk]

Folks who go through an awful lot of testing to find their "personal film speed" invariably end up with a 2/3 to 1 stop reduction in speed along with a corresponding decrease in development time.

So, it may seem that the old speeds were the correct speeds.

Not to contradict your thought (because you are right) but to extend it...

I am coming to the opposite conclusion.

Maybe it’s this booklet with all its choices that made me realize what I think is the really important message.

You start with a definition of the quality you are looking for. Then you work backwards (or take a number) based on that.

Zone System photographers want their shadows while holding their highlight in check. That is quite a different quality than a photographer who wants to enlarge 35mm film by 60 diameters. Which is yet another quality than the musician’s photographer who wants to capture the essence of the performance.

Another quality standard exists for the portrait photographer who believes all the contrast must exist in the face of their subject.

So I would recommend an exposure and processing system for my students, one that starts with the desired quality.

 

[Nicholas Lindan]

You start with a definition of the quality you are looking for. Then you work backwards (or take a number) based on that.

Couldn't agree more.

As to enlargement Vs film speed, I think the use of a lower film speed and less development leads to less grain. It's the developer that grows the grain from the exposed silver salt crystals.

 

[pentaxuser]

So, it may seem that the old speeds were the correct speeds.

Well they may have been correct but certainly not as sexy as the new high numbers. Take D3200 that can be used at 6400 or even above Now that has to be a faster and more powerful film that one that is rated at 36 DIN film surely. A 400 film gets almost stratospheric at two stops more. 1600 sounds as if a turbo booster has been attached. I already have images of the measured mile at the Salt Flats with that black line down the middle being eaten up at an ever increasing speed - Great!

If we go back to the old speeds or further back to DIN then suddenly all the air has been let out of the tyres with possible fatal consequences for that vehicle called "film"

pentaxuser

 

[ic-racer]

Yes, Bill, with the popularity of smaller formats and the desire to hand-hold the camera in the 50s onward, the two lower curves became more important. If you ask me, the situation was never adequately addressed until the advent of matrix metering in the late 1990s.

Safety Factors in Camera Exposures
PHOTOGRAPHIC SCIENCE AND ENGINEERING' Volume 4, Number 1, January-February 1960,

 

[Bill Burk]

it wasn't too bad, but then again I don't even notice how bad it is when its fresh.

Then there’s what you do. I will have to include a level of quality which recognizes for some the goal is to “have fun breaking all the rules”.

 

[138S]

Part of the rationale for reducing the safety factor in the 1960 revision was that many photographers using smaller formats were already doing this in order to get slightly better image structure/quality.

Usually "perceived grain" decreases as we overexpose, not a surprise as in each spot of the negative smaller crystals will be exposed if adding light, resulting more well packaged grains and some additional edge definition, wich of course it will be more noticeable in smaller formats as enlargements are typically larger.

Folks who go through an awful lot of testing to find their "personal film speed" invariably end up with a 2/3 to 1 stop reduction in speed along with a corresponding decrease in development time.
So, it may seem that the old speeds were the correct speeds.

OK, but IMO the old speed is not more correct or incorrect than the new speed, they are different references. Probably the newer speed was better for causal shooters and consumers, but it delivers an incorrect reference for the ZS.

ZS is no invention, it simply explains how film worked in 1940 until the 1960 speed change. As speed was modified we may not expect to have the speed point in Z-I as the ZS table explains, using box speed we record no detail until we are in Z-II.

Probably having 4 stops or 3 stops shadow latitude is more or less suitable depending on our display medium capability.

 

[Bill Burk]

ZS is no invention, it simply explains how film worked in 1940 until the 1960 speed change. As speed was modified we may not expect to have the speed point in Z-I as the ZS table explains, using box speed we record no detail until we are in Z-II.

This is the tough nuance... Plus-X before 1960 and after 1960 would give the same 0.10 density when given an exposure of 0.0063 meter candle seconds and developed to ASA parameters. In other words, the same amount of light would give you the same amount of density.

Zone System starts with an experimental exposure which gave 0.10 density and asks you to go back and turn the film speed dial on your meter until Zone I lines up with the meter needle.

No matter what anybody says the film speed is, the result of Zone System adjustment of a light meter will be 80 as a result of an experiment with Plus-X.

 

[138S]

This is the tough nuance... Plus-X before 1960 and after 1960 would give the same 0.10 density when given an exposure of 0.0063 meter candle seconds and developed to ASA parameters. In other words, the same amount of light would give you the same amount of density.

Zone System starts with an experimental exposure which gave 0.10 density and asks you to go back and turn the film speed dial on your meter until Zone I lines up with the meter needle.

No matter what anybody says the film speed is, the result of Zone System adjustment of a light meter will be 80 as a result of an experiment with Plus-X.

Bill, yes... 0.1D reference level is the one used by ASA pre-1960 and today, so not a surprise AA/Archer used it to define the first exposure allowing some detail, adhering to industrial standards of the ZS era.

There is no doubt that ZS table instructs to overexpose the 18% middle gray (Z-V) by one stop, allowing 4 stops shadow latitude... and adhering the 1940 (Pre 1960) film rating standards.

My view is that the Pro_vs_Anti ZS debates are usually out of focus, because the only remarkable point is that ZS aims a nominal +1 which is not a bad advice anyway, if we have light power enough. Still ZS newcomers should be warned that using box speed won't deliver detail in Z-I like the ZS table says, because at -4 we have black nominally, and this is because ZS table was made when industrial norms placed 0.1D at 4.3 stops underexposure, while today Box speed nominally places 0.1D at 3.3 stops underexposure.

IMO (for challenging scenes) the ZS 1 stop overexposure has a clear advantage, supose that we place the "scene middle 18% gray" in the "print 18% middle gray", probably Z-I will go mostly black in the print, but we can pull detail there by some dodging, that detail exists in a +1 ISO overexposed negative, but it is absent in a post 1960 exposure. Also ZS delivers have a nice 1 stop safety factor for -3 detail...

Probably one ends exposing the same if following ZS than if not, because at the end we use feedback to end in the right compensation in our decision making.

No matter what anybody says the film speed is, the result of Zone System adjustment of a light meter will be 80 as a result of an experiment with Plus-X.

Yeah... And suposing it is developed with Ilfotec DD-X or Xtol, with Rodinal probably we would end in an even lower EI...

 

[Sirius Glass]

When the ASA changed, I changed my light meter and the world was wonderful. That was back in the day that words were dirty and the air was clean.