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01-07-2022, 11:40 AM   #46
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Darts are fun, at least my niece said so after going to the PDC finals last week. I fondly remember when the provost insisted I could handle 32 kids in my 101 and 102 classes I'd give first day 'talks' on zone this and D -Log E curve that, and thin out the herd a bit.

01-07-2022, 11:41 AM - 2 Likes   #47
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QuoteOriginally posted by vonBaloney Quote
Yeah, my film days are solidly behind me anyway, but if I wasn't doing the printing then I just wouldn't be interested. To me, that's most of the game. Of course, if it is cheap enough and they wanna send me some small prints then I can use those instead of a contact sheet as a starting point. I was reading about caffenol in another thread, which I had never heard of (which was strange because in school there were all kinds of "alternative processes" explored -- Liquid Light, etc). Turns out it was invented after the last time I did any darkroom work. It was been a while, but if I wanted to shoot some b&w film these days, I'm sure that's what I'd do -- all developing and printing at home but with less nasty chemicals.
The problem with caffenol developer is the coffee. There is no way of determining if the Nescafe you used last time is the same as the Maxwell House you are using this time. Does the composition of instant coffee change over time enough that keeping the same jar of it specifically for mixing developer will give consistent results? The nice thing about it is that there should be no toxicity.

OTOH, the amount of Metol in D76 is very low, Hydroquinone is used in skin creams, Sodium Sulfite is pretty benign unless one abuses it, and really, the quantities involved in a home based darkroom are going to be so small that there will be no environmental issue anyway.
As with anything, a little common sense goes a long way.

---------- Post added Jan 7th, 2022 at 12:53 PM ----------

As promised, how to determine film speed. This is enlarger based, not scanning based, but one should be able to modify the methodology to scanning film.
Note that once this is dialed in we are no longer metering the shadows but rather we are metering the highlights. The nice thing about this is that light meters are generally more accurate at higher light levels anyway.

I think a lot of people inadvertently get it
backwards, and try to match paper to negatives.
I think it best to match negatives to paper.
Film is much more responsive to control than
paper.
Figuring out how to expose a film starts in the
darkroom.
Take an unexposed piece of the film you want to
use. Process it as per the manufacturers
instructions.
Set your enlarger head to a height that will
give a nice magnification for the print size you
want to make, most of the time.
Default to 8x10 if you can't decide.
Focus the lens and set stop it down 3 stops or so to its best aperture if you know it.
Do not change these settings for the duration of
the procedure
Put the processed film into the neg carrier and
make a series of exposures to find the time it
takes to make D-max.
You now have your stock exposure time for that paper, aperture and print size.

Now it's time to figure out your ISO.
You can set up a test target. or just go out and make pictures. What you are doing is finding out how your film speed/ developer combination handles bright areas. I like sunlit clouds for this, as it's about as bright a white you will get in nature.
Shoot a negative or series of negative and process the film however is normal for you, and expose it to your chosen paper using the settings you calculated for the D-Max paper test.
If your clouds are blown out, you need to shorten your development time, and may also need to lower your ISO. After a couple of exposure tests, you will probably know where you have to go, and how far until you get a suitable ISO/developer time to retain detail in the highlights. If you find your shadows are getting murky, you might find you need to lower your ISO, and/ or adjust your base exposure to the paper if you have had to shorten your film development time a lot. You might have dropped the base density + fog.

This technique is far better with sheet film, but will help quite a bit with roll film as well.
Now when you go shooting, you are metering the highlights rather than the shadows, as St. Ansel recommended.

Last edited by Wheatfield; 01-07-2022 at 11:54 AM.
01-07-2022, 11:55 AM   #48
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QuoteOriginally posted by Wheatfield Quote
The problem with caffenol developer is the coffee. There is no way of determining if the Nescafe you used last time is the same as the Maxwell House you are using this time. Does the composition of instant coffee change over time enough that keeping the same jar of it specifically for mixing developer will give consistent results? The nice thing about it is that there should be no toxicity.

OTOH, the amount of Metol in D76 is very low, Hydroquinone is used in skin creams, Sodium Sulfite is pretty benign unless one abuses it, and really, the quantities involved in a home based darkroom are going to be so small that there will be no environmental issue anyway.
As with anything, a little common sense goes a long way.
Sounds like you don't even actually have to use coffee -- lots of options. I'm not gonna do it, but it is interesting.
01-08-2022, 12:56 PM - 1 Like   #49
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QuoteOriginally posted by JohnMc Quote
Darts are fun, at least my niece said so after going to the PDC finals last week. I fondly remember when the provost insisted I could handle 32 kids in my 101 and 102 classes I'd give first day 'talks' on zone this and D -Log E curve that, and thin out the herd a bit.
Darts are even more fun when the person throwing them is blindfolded in a crowded room and has been spun around a few times.

01-08-2022, 01:58 PM   #50
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That goes without saying, or so I thought.
01-09-2022, 01:31 PM   #51
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QuoteOriginally posted by Denver Quote
When film was measured as ASA or DIN both were notorious for being overly optimistic rating.
I can't comment about DIN, but ASA (along with its successor, ISO) film speed was standard based using sensitometer (EI for n density above base fog) using manufacturers recommended development.


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01-09-2022, 01:37 PM   #52
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QuoteOriginally posted by vonBaloney Quote
Sounds like you don't even actually have to use coffee
That is basically true. While caffeine is a mild reducing agent, the vitamin C is probably the heavy lifter in most recipes.


Steve

01-09-2022, 02:03 PM   #53
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QuoteOriginally posted by stevebrot Quote
That is basically true. While caffeine is a mild reducing agent, the vitamin C is probably the heavy lifter in most recipes.


Steve
caffeine itself has nothign to do with the development. When you look caffenol up, the action is derived from caffeic acid, the name is similar but it is a compound that is common in many things. Even oregeno in sufficient quantity will work if steeped as a tea..


However, the issue is that the amount of tinkering needed to do with it, is almost aimed solely at people who want to keep the image of the mysterious and heroic photographer/developer/print maker struggling under harsh conditions to get a developed negative.

I mean, many people on other forums DESPISE stand or semi stand development entirely upon the basis of "so you put a roll of film negative on a spool, put 10ml of say rodinal concentrate in a developing tank, put the spool in the tank and slapped the lid on it. and then poured in 600ml of 20 c water in, shook it a bit and walked away..." just doesnt have that zing of

discussing how you measured out various chemicals, crushed little vitamin c tablets, and mixed it all up like some coke dealer and THEN developed film with it.
01-09-2022, 03:00 PM   #54
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QuoteOriginally posted by Wheatfield Quote
Hydroquinone is used in skin creams,
The jury's out over hydroquinone, apparently:–
QuoteQuote:
The FDA officially banned hydroquinone in 2020 as part of a larger reform of the over-the-counter drug review process.[22] The FDA stated that hydroquinone cannot be ruled out as a potential carcinogen.[23] https://en.wikipedia.org/wiki/Hydroquinone
I have no expertise in this, but I know some authorities decry the use of hydroquinone in film developers because of these misgivings. I do know I'd prefer to drink coffee: good coffee!
01-09-2022, 04:11 PM   #55
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QuoteOriginally posted by filmmaster Quote
caffeine itself has nothign to do with the development. When you look caffenol up, the action is derived from caffeic acid, the name is similar but it is a compound that is common in many things...
Well, I guess that dovetails nicely into the question at hand (whether coffee is actually an important ingredient in caffenol), since coffee is not a good source of caffiec acid...

QuoteQuote:
Caffeic acid is found at a very modest level in coffee, at 0.03 mg per 100 ml.
https://en.wikipedia.org/wiki/Caffeic_acid#Occurrences_in_food


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01-09-2022, 04:29 PM   #56
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QuoteOriginally posted by stevebrot Quote
Well, I guess that dovetails nicely into the question at hand (whether coffee is actually an important ingredient in caffenol), since coffee is not a good source of caffiec acid...


https://en.wikipedia.org/wiki/Caffeic_acid#Occurrences_in_food


Steve
you can get pure caffeic acid from chemical supply stores, but you would need to do the following

1. be a certified researcher
2. have a masters or higher level degree in chemistry
3. be engaged in anti cancer research

And last i checked, it would be about 1,300$ per POUND
01-10-2022, 02:51 AM   #57
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QuoteOriginally posted by Wheatfield Quote
The problem with caffenol developer is the coffee. There is no way of determining if the Nescafe you used last time is the same as the Maxwell House you are using this time. Does the composition of instant coffee change over time enough that keeping the same jar of it specifically for mixing developer will give consistent results? The nice thing about it is that there should be no toxicity.
Choose the cheapest brand will guarantee you no changes in time (I use the same brand since 2012)...

QuoteOriginally posted by filmmaster Quote
caffeine itself has nothign to do with the development.
Not totally true, it is the caffeic acid which is a compensating development agent. Ascorbic acid is the second development agent (don't use tablets, use powder) and washing soda is there to make the mix alkaline to activate the agents.
01-11-2022, 09:16 AM - 1 Like   #58
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QuoteOriginally posted by BigMackCam Quote
I have a question that I think I know the answer to, but I'd like to check with you good folks that have more experience

I've read quite a lot about many films having a box speed that's arguably higher than the "real" speed... for instance, ISO 400 films that are allegedly closer to 320, 250 or even 200 in reality. In several articles and posts I've read, the suggestion is to shoot at "real" speed rather than the box speed... but no-one ever mentions if the development times change. I assume they don't. So, if I shoot Fomapan 400 at, say, ISO 250 - 320 (as many would suggest) and therefore technically over-exposing it with reference to box speed, do I keep the development as per the Massive Dev Chart timings for ISO 400?

Thanks in advance
With Foma I usually shoot half of the box speed and develop in HC110 dil H (1+63) and I am getting great results.
Foma states that you can shoot the ISO 100 from 50-400, so I tried a 120 roll at 200 and it looks good too.
The times in the Massive Dev app are working good and I develop at box speed.
01-11-2022, 06:51 PM - 1 Like   #59
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Ive gotten great results shooting at stock speeds and developing as per the film manufacturers specs.

I push and pull only when I feel the situation warrants it. And mostly with color film.

(And when I mess up the ISO settings on cameras with AE)
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