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Michael Lloyd
18-Aug-2016, 20:32
I'm finally somewhat comfortable with shooting and developing black and white film (35mm, 120, and 4x5). I've made a lot of mistakes but things are going well enough that I'm ready to start making new mistakes :rolleyes:

I intentionally went out looking for a scene where I could try N+ or N- developing. As it turned out I found a scene that needed N-2 developing. No problem. I made the image and brought my test film home to develop it. I started trying to figure out what N-2 equated to in units of time. Well... there are a lot of rules of thumb on the web but the bottom line is I need to test my film. Ilford HP5+ (4x5) in this case.

One sheet was fine with normal developing and the other I winged and instead of developing at 9m in DD-X 4:1 I developed it for 5:34 (that might not be the exact time but it's close). The two negatives are drying and it'll be tomorrow evening before I can scan them. I'll post results when I get them scanned.

What is the process for coming up with N+ or N- times for a specific film and developer?

Bill Burk
18-Aug-2016, 21:27
Let me sell you a copy of my book. The last chapter tells you about N times...

http://beefalobill.com/imgs/20150812%20CallingYourShot-DividedAttention.pdf

Bill Burk
18-Aug-2016, 21:36
A physical copy of the book would come with a Stouffer scale...

So that scale is the first thing you need to buy.

Make a contact print exposure of that scale onto about 5 sheets of your film, and develop the sheets for a variety of times, like 4, 5, 7, 11, 15 minutes (assuming somewhere in the range is a time you normally use). Then read the densities of the different steps of the different sheets and fill out a spreadsheet or draw paper graphs. From that point forward you have the information you need to interpret "N" times.

neil poulsen
19-Aug-2016, 05:01
I learned this craft from The New Zone System Manual (White, Zakia, Lorenz. 1078). I see there's been a later edition, which I should get.

N+, N, N- development goes hand in hand with testing to determine an ASA that is suitable for use with the system (usually about half of Mfg. recommended), and it goes hand in hand with exposing for the shadows. White, et.al., does an excellent job of explaining how all of this comes together.

Willie
19-Aug-2016, 07:25
You might check with Fred Newman at The View Camera Store. I know he used to do film testing and many used the service. If he still does it you can really cut the time to get your processing down.

Doremus Scudder
19-Aug-2016, 11:33
Might I suggest a more empirical approach based on printing to find your N- and N+ development times?

The object of N-1 development is simply to get all the luminance values in a rather contrasty scene to fit on the negative so that they print well on a medium grade paper without a lot of dodging and burning. The goal is to reduce development time enough to get a luminance value that falls on Zone IX to print at Zone VIII. So, when you find that contrasty scene, shoot three negatives instead of just one (I'd give a bit more exposure too, maybe 1/3 stop to support the shadows since N- loses you a bit of film speed; just figure this as an E.I. adjustment for N-1).

Now, since you have "N" development nailed down, develop one of those negs 20% less and print it, aiming for faithful reproduction of the shadow value(s) you placed. If it's fine and your Zone IX luminance prints Zone VIII (white with a bit of detail), you've lucked out. If not, you have two more negs to fine tune with. Adjust development time till you get the values you want. That's your N-1 time.

Do the same for N-2 and the expansions, i.e., place a shadow and change development times to move the high values around till they print Zone VIII. For example, N+1 wants a luminance of Zone VII to print Zone VIII, etc.

Fine tune your development times as you work; if N-1 is consistently too contrasty, reduce the time a bit more and vice-versa.

That's all there really is to it. Sure, it's fun to play with the step wedges and plot the curves, but it's not really necessary. My approach is basically that mentioned by Neil above. I learned from "The New Zone System Manual" and recommend it too.

Best,

Doremus

ic-racer
19-Aug-2016, 12:42
What is the process for coming up with N+ or N- times for a specific film and developer?

In general, it depends on the type of enlarger (condenser vs diffusion) and your grade of printing paper. Many, including Ansel Adams and myself have had good success using multigrade paper and processing all negatives to 'N.'

Maris Rusis
19-Aug-2016, 13:21
In general, it depends on the type of enlarger (condenser vs diffusion) and your grade of printing paper. Many, including Ansel Adams and myself have had good success using multigrade paper and processing all negatives to 'N.'
Yes! In the past when photographic paper came as a fixed contrast grade it was important to "bend" the negative to fit the paper. This was done by N+ and N- development. Today the really excellent variable contrast papers enable the paper to be "bent" to fit the negative. Going up a contrast grade is the same as N+1 development. Go up two grades and it's a close match for N+2 development. Contractions work the same way, just in the opposite direction.

The big advantage of N development is that it doesn't close off the options of going up or down the contrast scale merely by changing paper filtration in the darkroom. For example if you have done a N+2 development and your visualisation changes toward a lower contrast version you're sunk. The negative won't easily go there. The N developed negative is more versatile.

neil poulsen
20-Aug-2016, 02:33
Might I suggest a more empirical approach based on printing to find your N- and N+ development times? . . .

Interesting.

Since Ansel Adams recommended (typically) selecting from only five (N-2, N-1, N, N+1, N+2) of the infinity of possible development times, there was never the expectation that the development time be "perfect," only that it be reasonably close.

I prefer doing all the curves, etc., etc., etc., etc., etc., etc., etc., etc. . . !

Perhaps what Doremus Scudder suggests will accomplish the same goal.

Select an area that you want to be about Zone II in the scene and meter it. The meter is designed to render it at about a Zone V. So to make it darker in the print, you need to expose the print to darken it by 3 stops so that it prints as an actual Zone II versus a Zone V.

Summary:

1] Select an area that you want to be Zone II.

2] Meter just that area. (Often, one needs a spot meter to get only that area.)

3] Observe the recommended aperture and shutter speed suggested by the meter, and change the settings to make the print 3 stops darker by some combination of increasing the shutter speed and decreasing the size of the aperture.

4] Expose the negative.

COMMENT: Some (like Ansel Adams, or White et. al.) recommend selecting a Zone III area and darkening the photo by two stops. I typically prefer pivoting on a Zone II area as I've described above.

COMMENT: As for developing everything to an N, and "compensating" using paper VC filters: In my experience (at least, to my taste), no amount of doing this will compensate for not having a properly developed negative in the first place. The print is just not the same.

Pere Casals
20-Aug-2016, 03:54
COMMENT: As for developing everything to an N, and "compensating" using paper VC filters: In my experience (at least, to my taste), no amount of doing this will compensate for not having a properly developed negative in the first place. The print is just not the same.

N+1 and N+2 increases negative contrast, useful for flat scenes... if N development with a "flat scene" with can be compensated with VC paper, but perhaps if not the same...

N-1 and N-2 developments are more powerful and solve critical issues. A lot of times we have an scene with high dynamic range, placing shadows at Z-III still highlights can be at Z-X, so an N development would burn those highlights as that area will reach max density "DMax" that is near 3.0D in TXP or T-Max. A N-2 development will extent film latitude 1.5 to 2 stops, as Z-X areas then fall at Z-VIII, while shadows at Z-III still are there.

For high dynamic range scenes I had good results with N-3 and N-4 developments, but pulling 1 stop not with reduced time, but with reduced agitation. Reduced agitation (every 3 min, for example) has a compensating effect as developer exhauts a bit on the highlights. With Xtol I develop (with reduced agitation) in trays, this prevents bromide drag stains. With rotary this is no as selective.

An then you can obtain a very difficult negative to print, with a lot of difficult burning/dodging.

My chalenge now is printing this negative https://www.flickr.com/photos/125592977@N05/24852468435/in/dateposted-public/

With PS I arranged easily to obtain a digital image, but after spending a lot of time in darkroom with it I think I have a lot of foraseable work to obtain a decent contact print with a lot of selective burning.

neil poulsen
20-Aug-2016, 07:03
. . . For high dynamic range scenes I had good results with N-3 and N-4 developments, but pulling 1 stop not with reduced time, but with reduced agitation. Reduced agitation (every 3 min, for example) has a compensating effect as developer exhauts a bit on the highlights. With Xtol I develop (with reduced agitation) in trays, this prevents bromide drag stains. With rotary this is no as selective. . .

Out of curiosity, what's your usual agitation?

I've also heard about increasing dilution for N- developments.

LabRat
20-Aug-2016, 07:13
In general, it depends on the type of enlarger (condenser vs diffusion) and your grade of printing paper. Many, including Ansel Adams and myself have had good success using multigrade paper and processing all negatives to 'N.'

+1, and mentioning that many films will change their "look" with changes in exposure & development, so if several prints hang on a wall, they will be harder to match the overall look in that series, and one might have a devil of a time trying to match them in the darkroom...

Steve K

Michael Lloyd
20-Aug-2016, 07:21
Thank you for all of the insightful replies and book. For now I am relegated to scanning and making platinum contact prints. I will have a darkroom one day. Soon I hope.

My "N-2" guess seems to have worked pretty well. The second image.. well... I screwed up and cut development time by 2 minutes. I wanted N+2. I saw the time was a little past N-2 and <duh> switched to the stop bath. As I was pouring the stop bath in I realized I had messed up. I figured it was worth taking a look. Composition isn't the best for both and focus was off on the second one. The tree trunks at the back of the scene were reading 4 EV on the Pentax and I couldn't see them very well on the ground glass (which begs the question, how does one focus in the dark?). I didn't want to get into reciprocity issues so I shot at f11 and 1s. In hindsight I should have taken some time and accounted for reciprocity. Then again, I screwed the development up so none of that matters.
I have some scans straight from Epson Scan and Negatives from Silverfast 8. I'm not good with either.

FWIW - I'll post the files. The negative is from Silverfast. The positive is an Epson Scan that has been fiddled with.

Composed and photographed correctly I think these have potential...

Negative one. No edits by me. Straight from Silverfast 8. SWAG for N-2. I shouldn't say SWAG. I used someones multiplier (no idea where I found it though. Probably this site)

The top left sky section is blown out but the central section of sky was probably saved by the development time change

http://wildlightimagingstudio.com/img/s1/v5/p1944831278-4.jpg

Slight edit of the Epson Scan negative. Epson Scan made it a positive so I just went with it

http://wildlightimagingstudio.com/img/s6/v135/p2094761629-4.jpg

Accidentally underdeveloped this negative

http://wildlightimagingstudio.com/img/s12/v179/p1947010616-4.jpg

And half-a**ed edited in Photoshop version of the underdeveloped negative scan

http://wildlightimagingstudio.com/img/s1/v5/p1978996254-4.jpg

Michael Lloyd
20-Aug-2016, 07:27
PS- I will add that although I like the convenience of the Jobo and without it or some other form of tank method I would not be developing my film, I can see the value in tray development. It was a pain in the neck to change development times. The tank had to be dried out after developing the first sheet. Then reloaded. If I could use trays life would be simpler (and I would have my darkroom that I've wanted for a long time)

Pere Casals
20-Aug-2016, 08:37
Out of curiosity, what's your usual agitation?

Standard development times are usually given for the case agitation is performed every 30s, of every 60s. http://imaging.kodakalaris.com/sites/prod/files/files/resources/j78.pdf

For a given film/developer combo... if you increase agitation you'll need less development time to reach same densities in the negative, but with more agitation you also obtain more contrast.

I usually agitate every 60s, and then I use development time it suits to the degree of development I want.

In case you are to obtain to much contrast for an scene you can decrease it by using reduced agitation, in this way developer is exhausted inside film emulsion of highlight areas as it reacts more with silver bromide, and also freed bromide inside emulsion slows development of highlights. As you agitate you put fresh developer inside film emulsion, so you make highligts development advance more... (if diluted developer this effect is more noticeable)

I use reduced agitation (every 3min) for night photography, than adds an N-1 to the count, so if you use a N-2 development time, with also reduced agitation you get a N-3.

If you want texture in your highlights you have to plan a development that do not allow highlights reach a too high density that is near to DMax.

You can event not agitate at all: stand development https://en.wikipedia.org/wiki/Stand_development.

Or "semistant", then you agitate only once at half time, usually.

I've also heard about increasing dilution for N- developments.

There is this interesting reading: http://johnsexton.com/images/Compensating_Development.pdf

With HC-110 you can control contrast with dilution, for this reason HC-110 is more suitable than other developers for rotary development.

Also:

Dilution for N- developments have 2 benefical effects:

A N-3 development will need a very short development time, then little time mistakes are a relative high percentage of development time mistakes. A diluted developer extends time, so it is easier to control a precise development.

The second one: when you perform an N- development it is because (usually) you have a too contrasty scene, so what you want is that higlights does not develop too much. If you use a diluted developer in combination with reduced agitation you reduce highlights development as developer inside emulsion is depleted earlier, as a diluted 1:1 developer has the half of active chemicals in every dop of developer, so the drop of developer that's inside emulsion is depleted earlier, when you agitate then fresh developer enters in the emulsion and bromide is removed in a faster way, then you reactivate development in the highlights. So... diluted developer is benefical in combination of reduced agitation to avoid highlights get overdeveloped while allowing shadows to be developed as developer is not exhausted there because it reacts less.

Also consider Adjacency effects (Search "adjacency" here: https://en.wikipedia.org/wiki/Photographic_developer) if agitation is performed at 1min or greater intervals, but this is of low importance in LF.

Bill Burk
20-Aug-2016, 08:48
Thank you for all of the insightful replies and book. For now I am relegated to scanning and making platinum contact prints.

You're welcome...

Don't these two kinds of printing require totally different negatives? Scanning wants a thin negative and platinum wants high contrast negatives, right?

I see this as a boon for you. Mistakenly develop too long and you'll make a negative good for platinum and vice-versa. Like your N+2 you accidentally developed N-2... no problem, just scan it. Make the opposite mistake, and you'll have your negative good for a platinum print...

PS- I will add that although I like the convenience of the Jobo and without it or some other form of tank method I would not be developing my film, I can see the value in tray development. It was a pain in the neck to change development times.

You can just make a bunch of test film exposures and keep them in a box. Then just drop a test sheet in the tank occasionally along with your regular run of film.

It is nice to have the whole family of curves done in one marathon... But you can do it "one sheet at a time."

I think the ultimate goal is to get enough information to make better educated guesses about the development time your film needs.

Michael Lloyd
20-Aug-2016, 08:54
You're welcome...

Don't these two kinds of printing require totally different negatives? Scanning wants a thin negative and platinum wants high contrast negatives, right?

I see this as a boon for you. Mistakenly develop too long and you'll make a negative good for platinum and vice-versa. Like your N+2 you accidentally developed N-2... no problem, just scan it. Make the opposite mistake, and you'll have your negative good for a platinum print...

Very true. One, now passed on, practitioner as he called it said something along the lines of - If you normally expose for shadows in Zone 3, put them in Zone 4. If you develop for N, develop for N+1. I think I have that right. The negative for platinum isn't very good for silver (so I've heard)

You can just make a bunch of test film exposures and keep them in a box. Then just drop a test sheet in the tank occasionally along with your regular run of film.

It is nice to have the whole family of curves done in one marathon... But you can do it "one sheet at a time."

I think the ultimate goal is to get enough information to make better educated guesses about the development time your film needs.

I need to find a one or two sheet tank for the Jobo. My smallest holds 6. But that's a good idea.

koraks
20-Aug-2016, 11:06
In my experience, negatives that are suitable for processes such as pt/pd or Van dyke brown also scan just fine even on a consumer flatbed such as the well-known Epsons. In fact, I've scanned negatives that had too long a tonal scale for Van Dyke on my aging 4990 and I could extract all the highlight detail that was in the high density values. I'm not sure where the wisdom comes from that scanning requires thin negatives, but I find it of very little practical relevance.

As to stand development: it's an excellent way to get uneven development. Getting even development with stand development in my experiences requires lengthy and daily prayers to miscellaneous deities as well as a significant amount of luck.

Jerry Bodine
20-Aug-2016, 14:54
...As to stand development: it's an excellent way to get uneven development. Getting even development with stand development in my experiences requires lengthy and daily prayers to miscellaneous deities as well as a significant amount of luck.

Have you thought about SEMI-stand development? I recall reading in The Negative that AA thought that using highly dilute HC-110 might provide some compensating action (to preserve highlight details) but cautioned about ensuring uniform development; so when I did my testing of HP5+ in HC-110 I decided to try it to see what could be achieved. Here's the plot (thumbnail) of what I got. If it's too tiny to read, I'll try to get it larger somehow. I can open this file in Irfanview and it's plenty big.

The development was done in trays, placing two 4x5 negatives (exposed identically) in a four-up hanger; one negative with a 31-step wedge contacted in-camera, the other without wedge to check uniformity. Agitation was varied for three such developments, as shown in the attachment, and was done by keeping the hanger submerged and slowly raising/lowering the hanger to prevent formation of bubbles.

koraks
21-Aug-2016, 03:10
Have you thought about SEMI-stand development?
I have thought about it, but never tried it. I might though, as I feel it could prove to be useful for developing negatives where reciprocity correction is an issue. I'm thinking of e.g. Fomapan 100, which suffers badly from LIRF and tends to yield excessively contrasty negatives when reciprocity correction is applied as suggested by the manufacturer. A semistand approach might be a good workaround. Maybe I'll give it a try one of these days.

Pere Casals
21-Aug-2016, 04:23
I have thought about it, but never tried it. I might though, as I feel it could prove to be useful for developing negatives where reciprocity correction is an issue. I'm thinking of e.g. Fomapan 100, which suffers badly from LIRF and tends to yield excessively contrasty negatives when reciprocity correction is applied as suggested by the manufacturer. A semistand approach might be a good workaround. Maybe I'll give it a try one of these days.

Not only with reprocity failure conditions: Every time that your film cannot record all dynamic range of an scene and you want to capture it, and every time you need to modify film standard nature to get a better printable negative.

Pere Casals
21-Aug-2016, 04:26
testing of HP5+ in HC-110 I decided to try it to see what could be achieved.

This is the way to do things! Just test it in controlled conditions! Technical accuracy ends with more time time for creative activity.

koraks
21-Aug-2016, 06:39
Not only with reprocity failure conditions
Uhm, that's kind of obvious, isn't it? Thanks for pointing it out anyway. I was just commenting on how I could possibly, maybe see it of any use in my own work, as I've never yet run into a situation where regular or even continuous development was an obstacle to getting a usable negative. The case with extreme reciprocity failure of Foma films is an exception, as correcting for that would very quickly have me resort to EI's as low as 25 or even lower than that, causing excessive halation around highlights. The compensating nature of a semistand approach could be a benefit as it may yield usable shadow detail without at the same time blowing the highlights too much AND having to resort to unpractical EI's.

Pere Casals
21-Aug-2016, 07:01
I was just commenting on how I could possibly, maybe see it of any use in my own work

Ok... I understand...

Also for night photography there is the possibility to use Fuji Neopan 100, with very low reprocity failure: no correction until 120s, and 1/2 stop with 1000 seconds, so exposures are often shorter than with HP5 / TMax 400, and at the same time with less development problems...

koraks
21-Aug-2016, 07:43
Yes, I know, thanks. Generally I shoot night scenes on TMX, which, while not as phenomenal as Acros in terms of reciprocity, works quite well for the purpose as it generally only requires about a stop of reciprocity correction in the situations I typically shoot in.

Bill Burk
21-Aug-2016, 10:20
Have you thought about SEMI-stand development? ... I did my testing of HP5+ in HC-110.

Is that right? The difference between agitation plans seems very minor. I think it may help to show continuous agitation or other scheme (agitate every 30 seconds) to get a fuller range of possibilities...

These differences are too close to call. I'd rather agitate every 3 minutes and develop for a minute less, while enjoying the comfort of knowing there is some tolerance than try every 5 minutes and risk uneven development if I misjudge time or temperature to the degree that causes results that you saw with agitation every 6 minutes...

"second best" (agitate every 3 minutes) about N-4 2/3...

"best" (agitate every 5 minutes) about N-5...

"worst" (agitate every 6 minutes) about N-5 1/3 ?

Jerry Bodine
21-Aug-2016, 11:54
...I'd rather agitate every 3 minutes and develop for a minute less, while enjoying the comfort of knowing there is some tolerance than try every 5 minutes and risk uneven development if I misjudge time or temperature to the degree that causes results that you saw with agitation every 6 minutes...

Bill, can't argue with your comments. But the goal in my tests was to try to push the processing limits, not to establish a routine. Testing was done on a day when ambient temp in the darkroom was 68F and a water jacket was used for the dev tray to minimize temp drift; dev time/agitation were watched very closely with a digital timer (trying to stay alert). In practice with a real negative I'd likely play it safe as you would. After the warm weather here abates a bit and the (un-airconditioned) darkroom cools off, I may redo the tests to establish a routine process with more leeway. But now I know where the limits are.

Bill Burk
21-Aug-2016, 12:24
I'm just really curious to know if you demonstrated that compensating development is not the same as reducing agitation...

Pere Casals
21-Aug-2016, 14:18
compensating development ... reducing agitation...

compensation development is not the same as reducing agitation, all of we know this

reducing agitation can have a compensating effect, more or less depending on developer and dilution, but compensation can also be done with Diafine and this is more related to developer nature than to agitation.

Jerry Bodine
21-Aug-2016, 16:01
I'm just really curious to know if you demonstrated that compensating development is not the same as reducing agitation...

I’m definitely not an expert on this topic, but I’d say compensating development is not the same as simply reducing agitation. I read AA’s comments on this topic before doing the tests. (Ref: The Negative 1981, p.226, FP4 curve on p.249). He explained that, although a highly dilute developer will behave like the same developer at normal strength if the time is extended sufficiently and agitation is normal, a certain amount of compensating effect may occur if agitation is reduced and the film is allowed to “stand” in contact with the highly dilute solution. So it’s the combination of high dilution and reduced agitation that provides the compensating effect.

The highly dilute developer exhausts quickly in areas of high exposure but remains active in areas of lower exposure, thus retaining shadow values/separations. Normal agitation would replace the exhausting developer with fresh and offset any compensating effect, so reducing agitation would allow some compensating effect. But reduction in agitation must also not allow uneven development. He reported his tests with HP5+ in HC-110 diluted 1:30 from stock for an effective compensating formula, suggesting a dev time of 18-20 minutes with constant agitation the first minute, then reduced to about 15s every 3 or 4 minutes, pre-soaking in water for at least 30s (which I did) before developing. I wanted to see what would happen to uniformity beyond 4 minutes.

It’s important to note that the compensating method preserves the shadow values better than simply reducing dev time, but will probably require extra exposure anyway (my tests showed the need for an extra stop of exposure). Looking at his FP4 curve, p.249, the extra exposure seems to be about one stop.

I recall when I first started b/w processing in the late 50s, with 35mm, compensating developers used one shot were recommended. So I studied up on the subject and came away with the conclusion that a compensating developer was formulated to do that; but my daylight tank was designed for constant rotary agitation. I also came to the conclusion (evidently incorrect) that the compensation was due to a resulting pronounced shoulder on the curve (not the slight shoulder seen on the FP4 curve). So I was a bit surprised to see an absence of any shoulder on my HP5 test results. So much to learn!