Determining optimum film speed and development

AnimalBones

AnimalBones

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I am selecting a couple of preferred film/developer combos

FP4+/510-Pyro
Delta 3200/Mytol

and want to work out optimal film speed and development time essentially using Adams method from The Negative. I do not have a densitometer (and its use may well not be compatible with 510-Pyro). Can anyone please help me with a reliable (and if possible, quantitative) method to calculate optimal negative density. I am shooting with a 35 mom SLR.

Many thanks
 
I was pretty sure I'd read a more recent example than the Adams one, and thought it was something by Tim Layton. I've looked on his website and I can only find one article where he refers to testing Tmax 400 (which for his developer he claims should be rated at EI 200). If I can find the thing I'm looking for I'll mention it here.

However, you say you don't have densitometer, but you still want quantitative methods, and that I find hard to understand... if you want quantitative methods, you surely have to measure something?

However, if I were going to try something like this, I think I'd try to take a standard scene at different exposures on short rolls, and develop them with different times (and presumably agitation methods), and compare the negatives... except, I just wouldn't. It seems to me much of the time the printing stage (or the scan/post-process/print stage) provides enough flexibility to cope with significant amounts of over exposure and some under exposure.

I have gone so far as to expose 12 scenes on a roll of redscale 3 times, at 50, 100 or 200 (or was it vice versa???) but I don't think I've done anything serious for black and white films...
 
Thanks. For quantitative I guess I meant semi-quantitative. I have seen an article on large format where a photo of white card has been exposed through a commercial negative of defined densities (Stouffer). This is then a semi-quantitative way to check discrimination between quantitative densities.
 
The step wedge idea is what I thought of, although I've never tried it. I guess it would then be a case of deciding how to interpret the results - either compare the negatives with the original to try and gauge the density in each step (the negs would go backwards, but should still work if the density steps are even), or just meter for the mid tone and see which EI and development cycle gives the most steps either side of that (and maybe try to gauge when highlights compress and shadows get lost in the film base). Would need to ensure that the wedge is lit such that there's a good brightness range in the subject for the camera/film to deal with.

Personally, I would just look at the Massive Dev Chart, pick an ISO/time/temp/dilution, and and it a go.
 
So, I think I have a method.

1. Scan a step wedge negative and image mean density for each step using imageJ. Generate a curve of density versus step value for the scanner.

2. Scan my test negatives and see where they lie on this curve.

I have access to a scanner and can buy a transmission step wedge. Any reason why this would not work?
 
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