yes, box speed, in a yasica d when i remember right.
what's your agitation technique, please?
Originally Posted by BetterSense
I guess the method is valid for a box speed. And what is the agitation technique?
Originally Posted by aleckurgan
3 quick inversions every minute
Originally Posted by Igor Savchenko
Please note my previous post. My take on the est by ALECKURGAN is that the test does not make sense to me. Please read it and my comments carefully before you try it.
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This is all insane except what photo engineer wrote. You got a film and a developer. Find a standard test subject, I use a doll with white blouse and black pleated skirt, grey scale and grey board. I illuminate with studio strobes so the target is the same reguardless of time or seasom. Expose so you get details in the blacks and run a test development. With some experience, you can look at the results and see if they will print. When you get close, make a real print, ascess it, tweek the time, retest. I have done this so long that 2 or three times will yield a good or perfect time.
How do they come out compared to manufactures times? Kodak times are very close. Ilford times with Ilford film is just as good. Ilford film with non Ilford developers are long, on purpose? MDC are totally screwed up. I can pull better numbers from the air.
I have had good luck with comparing times with one film and developer and extrapolating to another combo if only one variable is changed.
But nothing is as good as is my standard target and , a trial time , and making a print. We can`t be lazy.
Shooting some pics and then coming back to check how long to develope simply does not make it. There are no shortcuts unless you are an expert with a densitometer.
If you want to use 1/2 box speed, cut the time 20% It always worked for me. 2x box speed, well you will lose shadow detail unless something is a miss in the system and box speed was wrong for you like a slow shutter. I do not do this ever. I get a faster film.
Some of you guys who refuse to "push" film or treat it like religious sin crack me up.
Originally Posted by Ronald Moravec
You don't always need every single last piece of shadow detail, ya know?
Stop worrying about grain, resolution, sharpness, and everything else that doesn't have a damn thing to do with substance.
my agiation method is: the first minute full agiation, and then all 30 seconds 3 or 4 agiations
Shoot a test roll of an evenly lit, featureless wall. Expose alternatingly at -4 stops from the meter reading and at +3, for a seven-stop difference. Cut a piece from this roll, long enough that you get at least one plus-exposed and one minus-exposed frame. Develop, using your best guess for a time.
When the snippet is dry, measure the relative densities of the two frames by putting it on a light table (or other evenly underlit surface) and putting a light meter with the sensor in contact with the film, and taking a reading. I made a small snoot for the sensor on my Sekonic L308B meter. Otherwise, you can use a camera's built-in meter, if you create a mask with a cutout for the film, then place it over the lens.
The difference between meter readings from the two frames should be 4 stops*. If it's more, develop another snippet at a shorter development time and measure again. If it's less than 4 stops, increase your time.
This is the equivalent of using a densitometer. It's more accurate and faster than lighting a full-scale subject and printing the resulting negative.
Note that the -4 exposure should show a bit more than shadow of density compared to no exposure (it should actually be 1/3 stop over base density, but that can be tough to measure). If there's no density at all in the -4 frame, you may need to lower your EI and shoot another roll. However, if there's a lack of density and the contrast range is low, first increase your development time and process another snippet - it may be that there's insufficient -4 density because of gross underdevelopment.
*4 stops times 0.3 log = density of 1.2, nominally appropriate for diffuser enlargers. I've started developing to a range of 1.1 instead, finding that my current papers don't need that much contrast. That corresponds to range of 3 2/3 stops.
IMO, you should fill a roll with bracketed exposures of a MacBeth chart or other "official" grey scale, and do clip tests to determine the development time.
If you don't have one, buy one. If you can't afford one, rent one or borrow one. It is perhaps the most useful photographic testing tool you'll ever own.
Take notes of each exposure. Set your meter at box speed.
If using an incident meter, expose like it sez. If using a reflected meter, take a reading off of a grey card and open up 1/2 stop from what the meter sez.
Take your first exposure two stops more open than what the meter sez. Bracket up (in 1/2 or 1/3 stops, depending on what degree of precision your camera's aperture ring allows) until you are two stops more closed than the meter sez. Take some blank pix (lens cap on).
Do the same thing over again until the roll is finished. (If you are using 120, just shoot multiple rolls.)
When you go to develop, do clip tests, starting at whatever the recommended time is. If you have no idea, try something in the 8 - 10 minute range with standard dilutions (i.e. straight or 1:1). Try to cut the film where the blank shots are. If you don't get the cut right on, don't worry. As long as you are somewhat close, it will just be an extremely over- or under exposed frame that you cut. Try using a pre-cut length of something (e.g. string) to help you gauge the proper distance for the cut.
Then test development times until the MacBeth chart prints the way you want it to print on your targeted paper and grade. Use your optimally exposed contact sheets (film edges should be black or right near it) as a guide to choose which negs look the best to print.
Whichever negative you printed from that gave you the most accurate representation of the grey scale on the MacBeth, count how many shots away from the meter-recommended shot it was. In the future, adjust your EI accordingly. Whichever development time you used for that shot, that is your normal time.
It's one way of doing it. It is pretty simple, IMO. You just need to get that chart.
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