Preference for printing exposure times

[Jim Rice]

Yes but whatever it takes to achieve that quality print is, I would think, pertinent.

 

[Jim Rice]

I must say, Michael, that I truly enjoyed the 'carrier glass' post, so I will differ to you.

 

[NedL]

Michael, I think you're right of course, but this thread has been useful for me in other ways. I was wondering what the "black dots" on Bill's timer were like, and then he posted a picture. I think of my exposures in terms of percentages like Doremus, but I don't have a systematic approach like his. My test strips are 2 second intervals then 3, then sometimes 4; not based on any theory but just on how wide they should be based on my experience. Although honestly, it's not much of an "issue", I've found that once I've printed a couple from a given roll of film, the rest are usually similar enough that I can look at the negative and even make 1 second intervals around where it matters if I want to.

For dodging and burning, I tend to think in terms of percent of base exposure. It's interesting for me to learn how other people think about it. At my level ( still a beginner, but getting better ) the most important thing is not how I time but understanding and especially gaining a feel how the tones will change. For example, I have learned how dodging my low contrast exposure can help separate and bring out the darker areas on the print, but I don't have good intuition yet and need to make test strips to get it right. And sometimes it seems like there is just one amount of dodging that's just right, and if you miss much either way it's very noticeably not as good. If there is some way of thinking about it that will make that easier or more intuitive, then I'm "all ears"!

So yeah I agree that the goal is to make a great print and not meet some external thinking, but the chatter around that was valuable to me anyway.

 

[Jim Rice]

Though at the danger of hijacking this thread, what base exposure times for RA-4 would be least likely to cause reciprocity failure woes?

 

[Doremus Scudder]

Michael, I think you're right of course, but this thread has been useful for me in other ways. I was wondering what the "black dots" on Bill's timer were like, and then he posted a picture. I think of my exposures in terms of percentages like Doremus, but I don't have a systematic approach like his. My test strips are 2 second intervals then 3, then sometimes 4; not based on any theory but just on how wide they should be based on my experience. ...

For dodging and burning, I tend to think in terms of percent of base exposure. It's interesting for me to learn how other people think about it. ...

Ned,

Making a percentage test strip is easy. I like a 20% difference for my initial strip. I start with 10 seconds then cover a bit of the strip and count 20%, i.e., 2 seconds. The next strip should be 20% of 12 seconds, but that's close enough to 2 seconds, so I just give 2 seconds to the next bit of the strip. Now I have 14 seconds; 20% of that is really close to 3 seconds, so that's what I give the next bit. Now I have 17 seconds; 20% of that is rounded to 3 seconds as well so that's what the next bit gets. Now I have 20 seconds; 20% = 4 seconds here, so the next bit gets 4 seconds for a total of 24 seconds. The next strip will get 5 seconds to make 29 seconds, then the next gets 6 seconds to make 35 seconds total and finally, 7 seconds to make 42 seconds total.

Seems complicated, but once you figure it out you just count (with the metronome keeping seconds for you): 10 - 2 - 2 - 3 - 3 - 4 - 5 - 6 - 7 - off; easy and close enough to 20% so that the longer exposures have adequate separation - and you have a range of 10 - 42 seconds to choose from.

I think of all my dodging an burning in percentages also, and notate them as such in my exposure records. This is very helpful when scaling a print up or down. One simply finds the correct base exposure and then calculates the dodging and burning using the percentage of the base exposure. Of course, this is only a starting point, since different size prints almost always need some adjustments in this regard, but it is a very close starting point.

Best,

Doremus

 

[Ghostman]

Ha! I let the timer do the business in the DR, so I go with what that says...

but... The volume of the car radio... That HAS to be an even number (or a multiple of 5)

Sign me up to the OCD club Clive!

Wow, I've never met anyone else who had the car radio volume problem.

 

[Loulou]

Car radio volume (and TV volume for that matter) must be an odd number.

Wow, I've never met anyone else who had the car radio volume problem.

 

[NedL]

Ned,

Making a percentage test strip is easy. I like a 20% difference for my initial strip. I start with 10 seconds then cover a bit of the strip and count 20%, i.e., 2 seconds. The next strip should be 20% of 12 seconds, but that's close enough to 2 seconds, so I just give 2 seconds to the next bit of the strip. Now I have 14 seconds; 20% of that is really close to 3 seconds, so that's what I give the next bit. Now I have 17 seconds; 20% of that is rounded to 3 seconds as well so that's what the next bit gets. Now I have 20 seconds; 20% = 4 seconds here, so the next bit gets 4 seconds for a total of 24 seconds. The next strip will get 5 seconds to make 29 seconds, then the next gets 6 seconds to make 35 seconds total and finally, 7 seconds to make 42 seconds total.

Seems complicated, but once you figure it out you just count (with the metronome keeping seconds for you): 10 - 2 - 2 - 3 - 3 - 4 - 5 - 6 - 7 - off; easy and close enough to 20% so that the longer exposures have adequate separation - and you have a range of 10 - 42 seconds to choose from.

I think of all my dodging an burning in percentages also, and notate them as such in my exposure records. This is very helpful when scaling a print up or down. One simply finds the correct base exposure and then calculates the dodging and burning using the percentage of the base exposure. Of course, this is only a starting point, since different size prints almost always need some adjustments in this regard, but it is a very close starting point.

Best,
Doremus

Doremus,

Thanks, yes very simple! I too use the metronome, and my typical strips start at 8 or 10 and then go:

10-2-2-2-2-2-3-3-3-3... for low contrast, the change from 2 to 3 seconds at about 20.
then 2-1-1-1-1-1... for high contrast.

So they are fussier to make. Also I always mark the edge of the test strip with pencil lines, which takes extra time. ( But you can vary how far apart to make the important part of the test strip in the important part of the picture! ) For dodging and burning I probably think just like you "10% here, 40% in sky... ".

I will try your test strip approach the next time I make prints, probably toni`ght!

-Ned

 

[cliveh]

Wow, I've never met anyone else who had the car radio volume problem.

Now you mention it, I also have to have the car radio volume at an even number.

 

[Bill Burk]

10-2-2-2-2-2-3-3-3-3... for low contrast, the change from 2 to 3 seconds at about 20.
then 2-1-1-1-1-1... for high contrast.

Hey NedL, that is a good point... I'm using Grade 2 or 3 most of the time, so I don't have to "switch gears" but when I do need high contrast paper, my system goes out the window.

 

[Thomas Bertilsson]

It seems as if many of you have a lot of time on your hands (maybe too much...) when in the darkroom. Who really needs to worry about avoiding particular exposure times, or spend time multiplying and dividing by fractions of an f-stop?

For me it's whole stops on the lens, exposure times that allow me adequate accuracy (how the heck do you expect fractions of a second to be accurate with any timer?), and time for dodging. I prefer times in the 20-40 second range.

And, I alter exposure by percentages (and I make my test strips in percentages as well, rounded to the nearest full second), not fractions of f-stops, which seem overly unwieldy in the darkroom to me.

That and a metronome and I'm in business. I like simple and low-tech.

Best,

Doremus

Hi Doremus,

I like simple and functional too, so we definitely have that in common.

f/stop printing was pioneered by Gene Nocon, and is not difficult at all to do; no more difficult than counting any other sequence of seconds.
When I use f/stop printing I use full stops, but stopped down to f/5.6 or f/8 on the enlarger lens. If you wanted to do half stops, for example, just close the enlarging lens down one stop and boom you'll get the same results as half stops with the lens aperture one stop wider.

When I make my test strip I start at 90 seconds, and go backwards to 45s, 32s, 22s, 16s, 11s, 8s. Just like the f/stops on the lens. What's nice about that is that I see what extreme under/over-exposure of the paper does to shadows and highlights, and that always teaches me something about how I want to print the negative.
If I went about it by adding smaller increments, the spread from lightest to darkest would be smaller, and while it's not a method I recommend against, to me I wouldn't be exploring the negative enough.

Once I've nailed down a good base exposure, I start fine tuning it, and now I just add/subtract seconds with no concern for f/stops. After the base exposure is perfect I start working on details in the print, whether I want to add high contrast blasts or not, dodging, burning, diffusing, etc.

 

[smieglitz]

I test in 1/3-stops as well. The benefit of this method is that every strip has the same apparent visual increase in exposure effect because it is geometric in nature. Conversely, a constant increase in time by some fixed interval (e.g., 4 seconds) produces less and less exposure effect in each subsequent strip as the cumulative exposure increases. For example, going from 4 seconds to 8 seconds is 100% increase in exposure while going from 36 to 40 seconds is only about 10%.

While you can buy an f-stop timer to do a geometric sequence automatically, it isn't too hard to figure out a working sequence and set a timer manually. The sequence I use is:

start @ 8-seconds at some intermediate f-stop (e.g., f/11)
add 2 seconds to get 10 cumulative which is ~1/3-stop more
add 2.5 seconds to get 12.5 cumulative which is ~1/3-stop more
add 3.5 seconds to get 16 cumulative which is ~1/3-stop more
add 4 seconds to get 20 cumulative which is ~1/3-stop more
add 5 seconds to get 25 cumulative which is ~1/3-stop more
add 7 seconds to get 32 cumulative which is ~1/3-stop more
add 8 seconds to get 40 cumulative which is ~1/3-stop more
add 10 seconds to get 50 cumulative which is ~1/3-stop more
add 14 seconds to get 64 cumulative which is ~1/3-stop more

The full sequence above will give a series of strips that cover a 3-stop range in 1/3-stop intervals that appear equally distinct from one another. You will almost certainly hit the proper exposure somewhere in there if you are printing a decent negative. You could actually start at any initial time in the cumulative sequence (and end anywhere) as long as the next exposure follows the other sequence. IOW, start at 10 seconds then add 2.5 seconds, then 3.5, 4, 5, 7, 8, 10, 14. Every third number in the sequence doubles so the next few exposures to add would be 8 x 2 = 16, 10 x 2 = 20, 14 x 2 = 28, etc. So, it is easy to generate the entire sequence from any starting point if you can just remember the next three sequential additions (e.g., start at 16 and then add 4, then 5, then 7).

FWIW, shifting the decimal point in the ISO sequence for films (i.e., 80, 100, 125, 160, 200, 250, 320, 400, 500, 640...,) produces the cumulative exposure sequence above. Remembering that ISO sequence, I can quickly determine the cumulative time needed to expose the print. For example, if the 5th stripe looks good I think 80, 100, 125, 160, 200, so I know that stripe equates to 20 seconds for the print.

I keep a two-column table of these numbers on the wall next to the enlarger for quick reference. The first column is the exposure addition needed and the second column is the resultant cumulative exposure. That makes it extremely easy to generate or interpret a sequence of test exposures.

Hope that all makes sense. It is much, much easier to do than to explain.

 

[MattKing]

I keep a two-column table of these numbers on the wall next to the enlarger for quick reference. The first column is the exposure addition needed and the second column is the resultant cumulative exposure. That makes it extremely easy to generate or interpret a sequence of test exposures.

I have a similar table on a card that I stand up near my enlarger. Mine is in 1/2 stop intervals though.

 

[MartinP]

With such massive spreads of time needed in test-strips I can't help thinking that something must be wrong? The first work-print is by eye, from the neg and contact-print, and is easily within half a stop of the eventual base exposure. I mean most negs are more-or-less the same (within each film-type or format) as those one has printed before, and the paper works the same today as yesterday, so why feel the need to work as though you had never been in a darkroom before? What am I missing?

 

[Bob Carnie]

I have to agree , with all the talk on this site about how great metering is being done, understanding of film density and placement, It should be one test full sheet and move forward at an established fstop and time setting.
I think test strips with massive density swings is a waste of time and I would rather look at the print emerging in the developer to determine my next move.

With such massive spreads of time needed in test-strips I can't help thinking that something must be wrong? The first work-print is by eye, from the neg and contact-print, and is easily within half a stop of the eventual base exposure. I mean most negs are more-or-less the same (within each film-type or format) as those one has printed before, and the paper works the same today as yesterday, so why feel the need to work as though you had never been in a darkroom before? What am I missing?

 

[MartinP]

Not exactly a "standardised base print exposure time", but the characteristics of the film and paper are the same, and a glance at the neg and/or contact shows how much to aim off (and usually not very much) for a starting point.

 

[MartinP]

I'd usually use half a sheet, for example, 'straight' at the estimated time then maybe a few test sections to check details with too-much or too-little contrast/exposure before having a go at the print. It just seemed to me that people were describing starting off with completely new and unknown materials, while mostly that isn't the case?

 

[Thomas Bertilsson]

I'd usually use half a sheet, for example, 'straight' at the estimated time then maybe a few test sections to check details with too-much or too-little contrast/exposure before having a go at the print. It just seemed to me that people were describing starting off with completely new and unknown materials, while mostly that isn't the case?

Most of the time I'm able to guesstimate, but I like to explore the negative to the fullest. I do not believe that full shadow detail, or highlight detail for that matter, is always important, so that's why I do the f/stop test strip with each negative, to explore what the negative might look like at heavy exposure or lighter exposure. It teaches me things about the negative and how I'd like the final print to be.
To me that's simple enough and doesn't take any more time than making one single exposure at an approximate time. That single exposure gives me more work to do on the tail end, where I sometimes struggle to figure out how I wish to weight certain elements within the frame, and that is where the test strip is powerful to me.

To each their own. In my humble opinion, (and it is humble as I am a hack compared to many here), we have to find methods that work for us. My method is the best method for me, as I get prints that I like from that process.
Thank you for sharing your method as well!

 

[MattKing]

I have to agree , with all the talk on this site about how great metering is being done, understanding of film density and placement, It should be one test full sheet and move forward at an established fstop and time setting.
I think test strips with massive density swings is a waste of time and I would rather look at the print emerging in the developer to determine my next move.

Bob:

I find I do a lot more test-strip prints when I've been away from the darkroom for a while then when I am printing regularly.

And I do more test-strip prints when I am switching back and forth between films and formats, enlarging lenses and print sizes, then when I'm doing several prints from a single format and film, on to similar sized prints.

I would hazard a guess that the amount of time you spend printing might have an effect on your test-strip print usage

 

[Bob Carnie]

I stopped doing test strips back in the early 90's .

The main reason is with Lith printing one is forced to look at the print in the developer, as well with my solarizations.
After a few thousand prints I concluded that seeing the work emerge basically told one where dodge and burn was needed and yes after years calculating exposure aperture on the easel became an important skill I started to work on.
I just basically took the skill of making lith and solarizations and applied it to regular print making.

I look at each negative on the light box, and subsequent neg's are compared to make sure that I am working with consistent negatives with predictable results.
Then looking at the easel starts becoming a natural density to look for.
Then looking at the print in the developer becomes second nature.
Turning the lights on now is a step to only confirm what my next move will be. If I am on a streak my choices are already determined by the last few seconds in the Developer.

I have said this before and will say this again, printmaking should be fun and using a KISS method is better than any of the other methods I hear many pontificate here about. Reading their posts make me wonder how in the hell do they make images that are striking . I suspect the work is so boring , boring boring. This complexity is not needed in a darkroom to make good prints. Just a good eye and love for the process.

I have to say the amount of work I do weekly is not the reason for not using test strips but rather the lesson learned looking at the print developing out in the dev.
I do like MAS description of outflanking on full sheets of paper. I use this as well if I have screwed up on my questimate.

Bob:

I find I do a lot more test-strip prints when I've been away from the darkroom for a while then when I am printing regularly.

And I do more test-strip prints when I am switching back and forth between films and formats, enlarging lenses and print sizes, then when I'm doing several prints from a single format and film, on to similar sized prints.

I would hazard a guess that the amount of time you spend printing might have an effect on your test-strip print usage

 

[Thomas Bertilsson]

I have said this before and will say this again, printmaking should be fun and using a KISS method is better than any of the other methods I hear many pontificate here about. Reading their posts make me wonder how in the hell do they make images that are striking . I suspect the work is so boring , boring boring. This complexity is not needed in a darkroom to make good prints. Just a good eye and love for the process.

I couldn't agree with you more. While I don't tout my prints to be any sort of masterpieces, I do have fun when I print, and I enjoy it for other reasons too. It's a huge mental break.

From my perspective, I waste less paper when I do the test strips. And that's fun for me because a box of 11x14 Ilford is a hundred bucks, which to me is a lot of money. It has to make sense too.

 

[smieglitz]

With such massive spreads of time needed in test-strips I can't help thinking that something must be wrong? The first work-print is by eye, from the neg and contact-print, and is easily within half a stop of the eventual base exposure. I mean most negs are more-or-less the same (within each film-type or format) as those one has printed before, and the paper works the same today as yesterday, so why feel the need to work as though you had never been in a darkroom before? What am I missing?​

​

I have to agree ...I think test strips with massive density swings is a waste of time and I would rather look at the print emerging in the developer to determine my next move.

I'll defend my lengthy description and method by saying I'm a teacher and try to explain things so that others gain an understanding of a concept. (If you think I'm conveying wrong or useless information that is your prerogative, but I would disagree with you.) If you don't have much darkroom experience you probably haven't made the connection between standard materials and standard processing. And, I know from my teaching experience that students usually don't make that connection on their own, at least for awhile. Bob, you mention not using test strips from the early 90's onward, but why didn't you make that connection even earlier? I presume you've been at this more than 20-some years.

Conversely, testing with a a constant time interval is a big waste of time IMO. But, that's how most students have been taught and they don't realize there are other methods that may work better until someone leads them through it. Likewise, trying to guesstimate and creep up on the proper exposure is the common modus operandi for a beginner. Sometimes they are even unaware that a black tone lurks unfound in their printed negatives. They often underexpose a print and get a too-light image that is flat and gray yet they are happy with it. Hopefully that changes with additional experience and guidance. The fractional f/stop method almost guarantees a beginner will be able to determine the correct exposure on the test print somewhere between the two extremes of severe over- and underexposure. It has to be in the middle if one side is too light and the other too dark.

The lightbulb usually doesn't turn itself on when it comes to the f-stop sequence. All those standard f-numbers are useful to memorize for other reasons. The Inverse Square Law and memorization of the f/stop sequence makes light placement a snap in the studio. Want to make a light twice as bright? Move it from 11' to 8'. Need to calculate an extension factor with a view camera? Those f/numbers thought of as extension distances will tell you the proper exposure correction on your analog light meter. No calculation needed.

Another connection usually long in arriving is that the f/stops on a camera lens work the same way as the f/stops on an enlarger (which is also a camera). It's true. Going from f/8 to f/11 halves the exposure. Another simple, but for some reason a really tough concept to grasp unless directed to think about it is the "Sunny-16 rule." Why do many beginning photo students think they will get a proper midday exposure outdoors at 1/60sec at f8 with ISO 400 film when their camera meter is reading off the scale and flashing warnings at them? It's because they haven't made the connections yet on their own. Someone needs to point out that a camera meter really isn't needed for most outdoor exposures (or indoors if they always shoot under the same engineered lighting in similar rooms). If their camera is telling them something different than a stop either side of the Sunny-16 Rule on a sunny day with frontlit subject, there probably is a malfunctioning camera at fault or pilot error is occurring.

Another reason for the large "density swings" is the additional information provided on such a strip for burning and dodging. Or, when making larger or smaller prints. Or, using a different paper. The method I outlined earlier can be adapted to any time range - one doesn't have to start at 8 seconds for example. You could begin anywhere on that table, adjust the f/stop as needed, and do fewer strips if desired. If the geometric change between each strip is too much, stopping the lens down one stop lets the refinement be in 1/6 stops relative to the initial 1/3 stop sequence.

Granted, experience teaches that most negatives properly exposed and developed will print pretty much the same and a trusted starting point can be used and you wing it from there. But once you reach that level, you've experienced many other related epiphanies. Experience trumps. If you have it, good for you. Others need some direction and a method that produces good results or those connections may never be made. I think the f/stop method is a great way to teach and learn and standardize and become consistent in technique.

 

[Bob Carnie]

As I mentioned , printing Lith Prints had changed my outlook, If I had never made Lith prints I would not have caught on to looking in the tray for all the info.

 

[cliveh]

​

I'll defend my lengthy description and method by saying I'm a teacher and try to explain things so that others gain an understanding of a concept.

I think your method and concept is very sound, but also speaking as a teacher I think such methods have their place for normally exposed/developed film and for those with a great deal of patience. However, they do not always fit in with the variation of student and their experience, or those dyslexic to numbers. Students new to film will often produce extremely thin under exposed films, or ones that are partially fogged, or extremely dense. In such cases advice to get the best out of what they have quickly can often save demotivation about their thoughts on film and printing in general, so they may live to fight another day and improve.

 

[smieglitz]

@ cliveh, without exception, every student I've shown this method to over the years has remarked at how simple it all seemed afterward and they appreciate the fact they can see the change on every strip where the time method often confused them. Paraphrasing, they have also remarked "Why didn't my instructor show me this in the first place." Of course, I don't tell every student about it unless they seem to be having problems printing another way. "If it ain't broke, don't fix it" is more or less my approach. If I came across otherwise, it was not my intent.

We could go on forever discussing pedagogy and what works vs what does not and for whom. There is no blanket approach and flexibility certainly is worthwhile in that regard. Each student is different.

In my earlier posts I was just suggesting a method that in my experience seems to put it all together for certain individuals, though not often discussed. After figuring it all out independently years ago, I stumbled upon a very old Kodak Darkroom Dataguide (?) from Carnie's era that described the f/stop printing method and I've wondered ever since why it fell out of favor.