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Shopin' list for B&W processing

OK, this is the 3rd negative:-

M090603-016-small.jpg


It and the first one don't look to bad to my inexperienced eye (I've been shooting chromes only for more than 30 years), but the scans aren't great. I'm stitching on my Epson 4490 using the Epson scanning software - can anyone point me at the best settings for scanning B&W on an Epson flatbed?

The second neg looks stained and streaky - I think due to not doing the stop correctly and contaminating the fixer. Surely not a good idea to miss the stop and go direct to fixer?

How come that given that man has been processing B&W film for about a hundred years, there isn't a definite guide to how to do it? No two people seem to do the same thing with the same chemicals and film :-(
 
I mentioned Ansel Adams' The Negative above, and for many people it is definitive in explaining exposure and development (using the Zone system), in the context handling the conditions you face and the tonal range of the film you are using, to achieve the visualisation of the final print you want to achieve. Yes, there are other approaches which work well for other people, including alternative processes such as platinum/palladium, which is extraordinarily beautiful, and which I would like to try some day. The diversity of options, and the flexibility of the medium is one of its attractions.

Although I don't know the metering of the original scene for this third negative, it looks again like an under exposed and over developed negative. With transparency film you have a four or possibly five stop range, and you expose for the highlights, allowing the shadows to contain whatever definition they can; the opposite applies with black and white film, where you need to expose for the shadows and develop for the highlights. You need to rate the film lower - EI 50 or 64 is a good start for Acros - and experiment with times between 10 and 12 minutes at 20oC with Rodinal 1:50 in order to get the highlights under control. By doing this you will get a tonal curve of the right gradient, moving from shadow through to highlights.

For the rest of the development process, the advice already in this thread from several posters looks good and reasonably consistent to me. Use the stop bath for about a minute, agitating constantly. Get your fixer in (my time is the longest above, so you may want to try 4 or 5 minutes to begin with), wash in running water for at least 10 minutes, dip in Photoflo to break up the water surface, and hang to dry.

I hope this helps - good luck with the next batch!
 
These negs were definitely all over exposed - the last slightly less so.

Rated at ISO 100, the skies are all burnt out with very little detail but there is plenty of detail in the shadows. I don't understand how that can possibly make them under exposed.

Dunno what else I can say.
 
No. You have (I think) metered for the field, leaving the sky in zone 7 or 8. Your development has then pushed the sky beyond zone 8, and beyond the usable range of the film.

To deal with this, you need to do what I said above - get enough light on the film for the shadows, and pull the development.

If you do this, you should end up with something like this, but without the need to amend the contrast in photoshop to effectively do what I have just said (the sky is still blown, of course);

M090603-016-small.jpg
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In order to pull the development successfully, you will have to get more light on the film for the shadows, so that they develop correctly despite the pull - hence the overall effect is that you have both under exposed and over developed.

HTH.

PS - you could always try as an alternative a 1 or 2 stop ND grad filter, which would hold the sky back while you expose for the field.
 
This isn't always immediately intuitive, so here's a different way of trying to explain. You could make 5 different negatives of that same scene, all at the same exposure, and produce 5 different results from development, ranging from one where the sky is perfectly defined, but there the field is a featureless black (or very dark grey), to one where there is perfect definition in the darkest areas of the hedgerow and trees, acceptable definition and tone in the field, but the sky is a featureless white. Who is to say what the correct exposure is?

The point is to combine exposure and development in such a way that you can get an acceptable range of tone and definition from shadow through to highlight. In this scene, you need to do just what I have said above in order to achieve this.

It's quite different from using transparency film, where the range of control is more limited. In this case, I would place the sky on zone 7, and expose accordingly. I might even remember to use an ND grad filter to more closely match the exposure range in the scene to the usable range of the film, something I wouldn't bother with when using black and white film because I'd use a different approach, described above, to exposure and development.
 
Patrick

I asked this previously but I don't think you answered:

How, and with what, do you meter the exposure? e.g. reflected light, incident light, duplex metering...?

If the exposure is "right" then I would expect far more detail and contrast than the scans contain - in which case it is either the processing or scanning that is wrong.
 
I use a reflective light meter and I generally get reasonable results with E6 chromes, and B&W ought to be easier. On this occasion I screwed up and the E6 shot I took at the same time is overexposed. However, according to others you get 9 stops of range with Acros, so it should still be usable.
 
M090603-016-small.jpg


Hope you don't mind Patrick, I just thought I'd see how it looked with my post processing method. Are you realigning the levels histogram in Photoshop once it's scanned?
 
I scan my negatives at 4800 dpi and as16 bit grey scale positives with the black and white points set in levels, all done within the scanning software. Then when the image is opened in Photoshop I invert, crop any negative film border off, and if needed, rotate.

Then add a levels layer to realign the histogram by using "auto" or use the sliders. Assign a profile like Adobe RGB or whatever. Resize the image and then contrast sharpen using USM or smart sharpen.

I've never used the gimp, but I would imagine it works the same as any other editing software.
 
Yes, someone else suggested that I needed to play more with the scanning software levels, so I will try that tomorrow.

When you say 'realign the histogram', are you moving it up and down the brightness scale, or changing the contrast by resetting black and white points?
 
When looking at the histogram, the slider on the far left is the black point, and you move that to where the histogram graphic starts, at the very edge of the black hump. Then move the slider that is on the far right which is the white point, this should just touch the very edge of the hump. If you move them too far in, the image will clip the shadows and highlights.

Picture1.png


Do not move the gray point - middle one.

It is a good idea to make the preview image in the scanning software as big as it will go too, so you can see the histogram better.
 
I've messed around with the scanner software, and there is a lot more detail in the sky, but over all the image doesn't contain much in the way of blacks and is therefore fairly low contrast.

So my conclusion is that I should have exposed less, and maybe developed more to increase contrast.

I need to remember to meter for blacks rather than metering for sky/highlights with E6.

M090603Z-002B-small.jpg
 
It's the wrong conclusion. It does not follow that the sky highlights are blown out as a consequence of over exposure (for the reasons I have given a few times already).

If you expose less, and develop more, I can assure you that you will exacerbate the existing problem, and end up with much less detail in the shadows, and blown highlights. The good thing is that you can try for yourself and see the results.
 
Exposing less and developing for longer will give you no shadow detail, and you'll still get blown highlights as you've left it in the developer too long. Listen to Tantris :)
 
But I haven't got blown highlights - I just have no black and low contrast.

I'm begining to thing that B&W is not for me. There is just no pleasure in it.
 
Blown highlights and over development is no black and low contrast. The film sheet has been in developer too long. If you take a perfectly exposed piece of film and leave it in developer for much longer than necessary, you will end up with a low contrast, grey cast neg. If you do what Tantris says and meter for the shadows, you will get a range of greys, into blacks at the darkest point. Then develop thinking about the highlights which will stop you losing contrast in the shadows, and you will keep detail in the sky.
 
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