Development and ASA

CMoore · Aug 28, 2016

I tried searching (on Yahoo, not APUG), but i cannot find what i am looking for.
If you cannot find develop times for a certain film, can ASA be used.?
If i have film XYZ, and it is ASA 200, can i (usually) use the developing data from film ABC because it is ASA 200 also.?
I have some rolls of this:
Dead Link Removed.
FPP lists data for D-76, but my question still remains the same.
Thank You

MattKing · Aug 29, 2016

No.

The "EDU" part of the name is a clue though - it is the same as one of Freestyle's house brand.

Here is a link to their data sheet: http://www.freestylephoto.biz/pdf/product_pdfs/arista/AristaEDU_Ultra_200.pdf

By the way - you do know that it hasn't been referred to as "ASA" for decades.

Gerald C Koch · Aug 29, 2016

This film is repurposed surveillance film and was never intended as a general purpose film. For example such films lack an anti-halation coating. This can be seen in the sample night time photograph of the filling station. There are other differences. Be aware that you may not like your results. You get what you pay for.

Peter Schrager · Aug 29, 2016

seems like the edu part is pure BS if it's surveillance film....I would agree with Gerald Koch...doesn't mean it won't float oyur boat photographically
best, peter

Gerald C Koch · Aug 29, 2016

From FPP site. "Our FPP EDUbw200 film is a black and white surveillance film made by FOMA." Some people like the effect that these films produce and others hate it.

CMoore · Aug 29, 2016

That raises another question with Ilford.
Is it normal, under most circumstances, to treat ID-11 as if you were using Kodak D-76, as far as the Kodak Development chart is concerned.?
The film was cheap, so i bought a few rolls to see what it looks like.
It has been 30-35 years since i did anything with a camera. I guess the term now is ISO. It was ASA when i had cameras, and the cameras i have now use ASA, so i suppose i never modernized.

guangong · Aug 29, 2016

Despite the hype, I do not believe that there is really any difference. ISO is ASA/DIN, e.g. ISO 100/21. Probably saves a little space and ink on label instead of ASA 100, DIN 21... 10 type spaces instead of 14. Also hides the national origins of America... (ASA) And Germany...(DIN) to protect the delicate feelings of those countries whose systems fell by the wayside. All of my cameras have either ASA or DIN. Only a few recently purchased meters have ISO.

Gerald C Koch · Aug 29, 2016

guangong said:
Despite the hype, I do not believe that there is really any difference. ISO is ASA/DIN, e.g. ISO 100/21. Probably saves a little space and ink on label instead of ASA 100, DIN 21... 10 type spaces instead of 14. Also hides the national origins of America... (ASA) And Germany...(DIN) to protect the delicate feelings of those countries whose systems fell by the wayside. All of my cameras have either ASA or DIN. Only a few recently purchased meters have ISO.

The methods used to determine ASA, ISO, DIN, and GOST are all different from one another. Therefore what rating method is used determines the box speed.

MattKing · Aug 29, 2016

Gerald C Koch said:
The methods used to determine ASA, ISO, DIN, and GOST are all different from one another. Therefore what rating method is used determines the box speed.

Gerald is right, but when it comes to "normal" black and white negative film, there is enough intersection between the results obtained using each method that you can get good use of ASA information when working in an ISO world.
As long as your ASA information isn't more than about 45 years old.

CMoore · Aug 29, 2016

So how does this all work anyway.?
Does the ISO develop certain parameters regarding film speed, then the film manufacture uses that data to stamp a box (for example FP4) at 125.?
Or do the chemicals used in the emulsion have a known outcome for Speed/Sensitivity.?
Thanks

Gerald C Koch · Aug 29, 2016

To expand a bit on what Michael said. The ISO standard allows the film maker to choose what developer to use. The other methods each dictated a specific developer.

The film speed is determined from the characteristic curve obtained for the particular film.

https://en.wikipedia.org/wiki/Film_speed

Bill Burk · Aug 29, 2016

And as for how it all works, the tail kind of wags the dog...

ISO specifies the parameters. Manufacturers plan what they want the film to be like. People like film that's fast, like 400 so manufacturers work to hit that goal. Boxes get printed with the speed already on them... Manufacturers make up some film samples in their test lab, test it and tweak the film's emulsion until it meets the speed and a host of other characteristics that make you love film, then they make a production run with the formula they came up with in the lab.

You get film with speed that matches the box speed because the manufacturer made the film that way.

Now when you mess around testing film speed on your own, you are usually trying to see if you can get the same results the manufacturer did, and you usually make some mistakes or have some other uncontrolled condition that causes you to not get the speed they got. No big deal because over time you learn to use an exposure index that is higher or lower than the rated speed (you learn to push, or you like to get extra shadow detail, etc).

MattKing · Aug 29, 2016

Or, you do tests and arrive at an exposure index/speed that gives you results that are different than the results that those who developed the ISO standard were seeking.

It seems to me that the ISO standard tends to result in negatives that maximise mid-tone and highlight rendition, while still giving good shadow rendition.

Those who prefer to give their shadows more exposure - assign a lower EI to films - may be more willing to use printing techniques to obtain mid-tones and highlights they like. Certainly modern films make it much easier to do that now.

darkroommike · Aug 29, 2016

Gerald C Koch said:
The methods used to determine ASA, ISO, DIN, and GOST are all different from one another. Therefore what rating method is used determines the box speed.

Not anymore, since the last ISO standard 1974(?), ISO, din, and ASA are determined the same way and correctly convert from one to the next. And since 1987 GOST has also been realigned with ISO. The old GOST scale was very close to ASA but used a film base + fog of 0.2 rather than 0.1.

darkroommike · Aug 29, 2016

And getting back to OP's question. If I cannot find a processing time for "X" in my soup du jour I'll find a time for D-76 and note the time then find time and temp for a similar film in both my favorite soup and D-76 and apply a correction factor.

Kevin Caulfield · Aug 29, 2016

darkroommike said:
And getting back to OP's question. If I cannot find a processing time for "X" in my soup du jour I'll find a time for D-76 and note the time then find time and temp for a similar film in both my favorite soup and D-76 and apply a correction factor.

Yes, exactly what Mike said.

Poisson Du Jour · Aug 30, 2016

Oh, ASA is still used.
A front-of-house may warble to a barista for an ASA: 'a skinny affogato'!
I like the reference to ASA on my Pentax 67 film speed dial. It's proof of its vintage heritage...
Chip, you'll have to find a book — a lexicon of sorts, to update you on current day photographic terms. But then again, you've always go APUG to correct you...

CMoore · Aug 30, 2016

Poisson Du Jour said:
But then again, you've always go APUG to correct you...

Yes.......there is always that.

Kevin Caulfield · Aug 30, 2016

Poisson Du Jour said:
Oh, ASA is still used.
A front-of-house may warble to a barista for an ASA: 'a skinny affogato'!
I like the reference to ASA on my Pentax 67 film speed dial. It's proof of its vintage heritage...
Chip, you'll have to find a book — a lexicon of sorts, to update you on current day photographic terms. But then again, you've always go APUG to correct you...

got

CMoore · Aug 31, 2016

Peter Schrager said:
seems like the edu part is pure BS if it's surveillance film....I would agree with Gerald Koch...doesn't mean it won't float oyur boat photographically
best, peter

I developed two rolls. I went 5.5 minutes in ID-11 at 70 degrees.
The negatives look "good". I am Very Much a beginner...but they seem to have "normal" Contrast/Information.
I am still about one month away from my enlarger operating, but the contact sheet will say more.
At this point, i should probably just stick with FP4 and HP5 (400).
On a side note, just regards to available Light and the in-camera Meter.....HP5/400 sure is a joy compared to FP4. The extra light was pretty staggering the first time around, when switching from ASA 125 to 400.

Gerald C Koch · Aug 31, 2016

darkroommike said:
Not anymore, since the last ISO standard 1974(?), ISO, din, and ASA are determined the same way and correctly convert from one to the next. And since 1987 GOST has also been realigned with ISO. The old GOST scale was very close to ASA but used a film base + fog of 0.2 rather than 0.1.

I was speaking in the past tense, "The methods used ..." I do value your clarification as to dates of conversion. ASA, and GOST are extinct. DIN is merely the logarithmic representation of the ISO value. It is still listed on some film boxes.

Development and ASA

CMoore

MattKing

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Gerald C Koch

Peter Schrager

Gerald C Koch

CMoore

guangong

Gerald C Koch

MattKing

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CMoore

Gerald C Koch

Bill Burk

MattKing

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darkroommike

darkroommike

Kevin Caulfield

Poisson Du Jour

CMoore

Kevin Caulfield

CMoore

Gerald C Koch

Development and ASA

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Privacy & Transparency