What dorff said.
The purpose of the negative is not to give you an exciting scan or print. Its purpose is to hold all the detail of the scene necessary to make your final scan (through Photoshop adjustments and curves) or your final print (through contrast filters, burning/dodging).
Whatever EI and developing schemes get all the detail you need on the negative are the right ones.
Let's get off the scanning talk. That's not for here.
I shot hp5 from 160 to 800 and could never get it to do what I wanted. But I could always get it to look decent.
I'm wondering about the developer as well. I use D76 for Tri-X, and I have used it for HP5 as well, but Acufine gave me a look w/ the HP5 that I preferred. One thing I would suggest (and I wish to goodness I would follow this myself) is to make only ONE change and see how things go. Usually, the differences in ISO that you're talking about are pretty small when shooting HP5. Developer choice, developer freshness, agitation procedures, the light that you took the photos in, your metering technique, etc can all influence what your neg looks like.
I also concur that even though the negs may look different, you may not see much difference on the prints if you use your graded papers/filters to get a print that you like. Since the neg is the next to last stop in the process, I would make some prints and see what's up.
Ilford HP 5 @ 200, developed in Moersch Tanol 1+1+100 or PMK 1+2 +100 for time of ISO 400. Makes for excellent negatives
What film speed do you like your prints best at? That's the speed you should be shooting at.
Making negatives that work well with the rest of your work flow will remove a ton of frustration in the darkroom come printing time. And to make such negatives, some testing is required.
You are probably unique in what your situation is, and if you think about it, all of these factors play into what speed you should expose HP5 at to give YOU pleasing results:
- Your lighting conditions / quality of light where you live and photograph
- Your metering technique
- Your meter accuracy
- Your lens
- Your shutter accuracy
- Your water supply
- Your film developer
- Darkroom thermometer precision and accuracy
- Your film developer dilution
- Your agitation technique
- Your printing paper
- Your paper developer
- How long you develop your paper for
- Paper developer dilution
- Darkroom 'safety level' (how dark is it really, and is your safelight safe?)
- Are you going to tone your prints or not?
There are a zillion factors that play into how you should expose your film!
Now go shoot some film, have fun, and figure out what you must do to get the results you want.
Why not shoot at box speed and develop to what you find best?
I shoot a lot of HP5+, mostly in 4x5, here is what I do:
I set my meter to 400 (box speed).
I place the darkest area where I want to retain detail in zone IV
I expose two sheets identically (both sides of a film holder)
I develop one sheet normally (I use Ilfotec HC at 1+31 for 6.5 mins)
I inspect the developed sheet to make sure that I have detail in the shadows, and in the highlights, if not, I adjust development for the second sheet.
For roll film, with normal contrast subjects, that would be similar to rating the film at 200.
All depends on both your developer, the lighting ratios in your scene, and what kind of midtone expansion you want in the print. For ordinary
use I generally just use box speed, i.e., 400. But there are times when I want better differentiation of the deeper shadows and will rate it
lower. This film has a bit of toe to it, so for me sings best when the contrast range is not extreme. That way I can give it a bit extra dev for
that wonderful midtone separation and edge effect this product is noted for. I use PMK pyro.
I just recognized that if some of you are on your toes, you'll see any apparent contradiction in what I just posted. More exposure for more
development. Yup. Might go against Zone theory, but then I control the otherwise blown-out highlight with either an unsharp mask or, more
often nowadays, by punching in highlight details by split printing some of these newer excellent VC papers. We do have some tricks that one
won't read about in those old Ansel guides.
Well, you have some advice to sieve through here! Technically, Thomas covers a great many things that you should consider, but if you are like me and have limited time juggling family life, a professional career and a few other interests, then you would want to take a few short cuts with the least risk of losing something important. So think about the following:
Change one thing at a time, until you are sure you understand how that affects you. The most important things are (in my view): Choice of developer and dilution; agitation (do not underestimate this!); developing time; temperature; exposure (including any bias/fault on your camera or lightmeter). If you add filtration, that will change a few things, especially how skin and sky are rendered. If you do not have a densitometer, and cannot make darkroom prints, it will be quite difficult to benchmark. So if you could maybe borrow a densitometer, or mail your test negs to somebody who can print or measure them for you, that would help.
The following is an easy (but tedious) way to get to more or less understand the materials you are working with. You want to know how to expose and develop while being able to maintain detail in both the shadows and highlights into the zones that are important to you. The technique I use comes from John Blakemore's Black and White Photography Workshop. You have to take something like a single-tone towel or coarse fabric - something that has texture. Flat and smooth objects like white walls and paper do not give you any means to gauge whether detail is visible or not. Colour patterns won't help either. So you take your towel, and using the zone system designation, photograph it at zones 0 through X. Develop and print (or scan) for zone V, then print all frames at the same exposure, and assess where you are in terms of visible detail. That will then give you an indication of how to expose. You could force the contrast up or down by changing the developing time, but only if you know what you are doing, and having exhausted your tests at the standard developing time. You will do this once for every film/developer combination, which is why almost all the experienced guys advocate sticking to as few as possible. Three films and three different developers already give you 9 tests to run. It grows exponentially if you have more. It might surprise you, but after having done this with FP4+, HP5+, Acros and TMax 400, I am back to exposing at box speed and developing at standard times with Rodinal 1:50, with agitation once a minute as two gentle inversions. This gives me more than enough in the negatives to work with in terms of dynamic range, and the negatives have punch and accutance when printed close to Grade 2, assuming average lighting and subject contrast. There is one important caveat: I expose for a zone, rather than averaging with the camera lightmeter. That is usually zone IV, the "high shadows", sometimes zone III. I almost never bother about the highlights, but if the contrast is high and the highlights are very important, I might meter them and reduce the developing time. Since I shoot roll film, that is the exception and not the rule. BTW, you are lost without a spot meter, either in camera or handheld.
Since there is an aversion to zeroes and ones on this forum, I will not delve into your scanning methodology. Suffice it to say that some scanners (and/or software) fare less well with black and white negatives than others. You might want to solicit advice in the appropriate forum on that topic. It took me a while to figure it out, and I am still not nearly as happy with scans than with my darkroom prints from the same negative. The upshot of this is that it motivates me to make darkroom prints, since I absolutely want to see what the negatives are capable of.
EDIT: Drew makes it sound as if it is easy to use printing techniques to salvage a negative. While experienced printers make it look easy, in reality it is not so simple. At the very least, it is time consuming. There are some scenes that are nigh impossible to expose optimally for the entire dynamic range, and then such techniques are very useful to get a quality print. But they are for most of us the exception and not the rule. You should not expose and develop your film in such a way that special techniques are required for every subject. Then you are definitely doing something wrong.