Split Grade Printing Test Strips + Method

[Ben wright]

Hello,

A newbie darkroom question im afraid regarding split grade printing and test strip methods.

I have been using the method outlined by Les McLean for about a year now and have been reasonably happy with the results. Im trying to make my test strips more efficient in time and materials but also gain most amount of info with fewest steps.

The method I’ve been using is to make a test strip with Grade 0 and select the best one for highlight detail. Then a second test strip with the chosen Grade 0 exposure over the whole strip then Grade 5 test strip over the top to determine the black points of the print.

As far as I can tell this method is just setting your black and white points and letting tones fall in between to create a good starting point prior to dodging and burning. My questions are as follows:

1. I know Ilford suggest doing an initial test at Grade 2.5 and then dividing by two to give Grade 0 and Grade 5 times. Does this method have any advantages over the one outlined by Les McLean. A few of the videos I have seen of the Ilford method seem to end up not quite getting there with dark tones and have to do a further adjustment. Is the Les McLean method better because you can see all the grade 5 times overlaid on the Grade 0 and make a better exposure time selection?
2. Ive been using an 8x10 sheet cut into quarters for the test strips and laid across the image. Sometimes these are hard to interpret as the correct exposure isn’t at the most optimum point on the test strip. I have been researching localised test strips. Is it a good idea to do a localised test strip for a highlight area (to set white levels) and then a localised test strip on a shadow area to set the blacks? Would this get me to the same place but with more accuracy?
3. I know a lot of people use f-stop timing for darkroom prints. Although I’m a little confused I think I understand some of the plus points of this method. I quite often print and if I don’t get test prints that are as visualised in my mind I find myself guessing additional exposures for dodging and burning which seems tricky for an inexperienced printer and wastes time and paper. Is the f-stop method going to be doing me any favours for making a more educated decision towards better prints.

Many thanks Ben

 

[Nicholas Lindan]

There is already a thread on this topic:

https://www.photrio.com/forum/threads/split-grade-printing-technical-analysis.186517/

 

[radiant]

The method I’ve been using is to make a test strip with Grade 0 and select the best one for highlight detail. Then a second test strip with the chosen Grade 0 exposure over the whole strip then Grade 5 test strip over the top to determine the black points of the print.

I've also read that you should do it in reverse when dealing with low contrast or high contrast image. I cannot remember anymore what way it was

have been researching localized test strips. Is it a good idea to do a localized test strip for a highlight area (to set white levels) and then a localised test strip on a shadow area to set the blacks? Would this get me to the same place but with more accuracy?

I think localized test strips is the only correct way to do test strips. At least it is 10x better. I was struggling with the same issue as you until I found out about LTS method. LTS tool is really easy to make from cardboard.

Is the f-stop method going to be doing me any favours for making a more educated decision towards better prints.

I have also strong opinion about f-stop printing; that is also the only decent way to print. Everything works in "stops" so why adjust time in seconds? It is really hard to estimate correction in seconds if base time is varying in your negatives, enlarging size etc. Also burning/dodging comes very much intuitive.

I'm using f-stop LED enlarger where all these are combined in same package. No more filter juggling, no more thinking of times. Making test strips for different contrast - easypeasy. Makes printing so much productive and I can concentrate much more on the output.

 

[Doremus Scudder]

An alternative method:

I use split-grade dodging and burning a lot, but like to find a single contrast setting for my base exposure. I find this easier and more economical of both time and paper.

Therefore, a single test strip is made as follows:

1. I guesstimate the contrast I'll need from the proof or from a visual evaluation of the negative. I'll start there. let's say I'm at roughly grade 2.5, or 30M or so on my color head. I make a test strip using a strip of paper, usually a third of a sheet cut lengthwise. I try to place the strip so that the middle of it is in an important highlight in the print (not always easy, but usually doable).

2. I expose the test strip using percentage times (much easier for me than f-stop timing and basically the same thing). I start with a 30% test strip (I've figured the times and have them memorized), which I make by successively covering the strip with a card. For example, I'll start with 10 seconds, then cover the first strip and count 3 seconds (30% of 10), then I'll cover the next stripe and count 4 (3.9 seconds is 30% of 13). Now I've got 17 seconds total, so the next stripe gets 5 seconds (5.1 is 30% of 17). I'll continue with this scheme adding successively longer times as I go. My 30% scheme is: 10-second base exposure and then successively cover strips counting 3, 4, 5, 7, 9, and 11 seconds. That gives me a strip with approximately 30% intervals with the following exposures: 10 sec., 13 sec., 17 sec., 22 sec., 29 sec., 38 sec., and 49 sec. (I like print exposures in the 20-30-second range).

3. After developing and fixing the test strip for a minute or so, I'll turn on the viewing light over the fixer tray and evaluate the strip. I'm simultaneously looking for good highlight tonality and detail (for the basic print exposure) and contrast (since I'll likely have to adjust contrast). If the contrast is way off, I'll adjust the setting on the color head and make a second test strip as above. Usually, however, the contrast is close enough that I can just tweak the setting, say adding or subtracting 10-30 units of whatever filtration I'm using (if you're using filters, that's tweaking a half-grade of filtration or so). Let's say I have a good starting exposure (highlights look good at, say, 22 seconds), but I need more contrast. So, I'll add 20-30M or so and add 10% to the exposure for the additional density and then make a full-sized test print. Yes, the exposure may be slightly off, but my first straight print never gets saved anyway.

4. After processing the first test print, I'll evaluate and make any changes in exposure, contrast, etc. as well as deciding on a scheme for manipulations. Here's where the split-grade part comes in (when needed - often it isn't). If I need a lot more contrast in a certain area of the print, I'll first try burning with the highest-contrast filtration. If that overexposes the area, then I'll hold it back during the base exposure and then burn back with the high-contrast filtration. For areas that need lower contrast, I'll dodge during the basic exposure and burn back with the lowest-contrast filtration. Finding the proportion between base exposure, dodging and burning back is the trick here. For areas that are overly-contrasty and don't have highlight detail, I'll just burn a bit with the lowest contrast filter if I want to keep the other values as they are. Plus, I can always burn with the basic filtration too. Lots of possibilities here.

But we're way past making test strips here... Notice I usually only make one or two test strips before moving on to the first straight print. I imagine I could make one test strip, process it, change contrast settings on my enlarger and make a second in about the same time as it takes to make the strip with exposures from both settings. And, I often only need to make the first strip.

Les McLean's method works too, but isn't exactly accurate in terms of final exposure either. That base exposure for highlights that you decide on from the low-contast strip is more than likely not going to be your final exposure time. If you need even moderate amounts of high-contrast exposure, those highlights are going to be affected and you'll have to reduce the base exposure to keep them from becoming too dark/muddy. That means, that when you get the shadows right on the second strip, you'll end up with over-exposed highlights. You could reduce the basic exposure and make yet another strip, or even as a general rule, reduce the basic exposure before making the second strip by 10% or a bit more. Still, fine-tuning the low-contrast overall print exposure is probably going to be necessary to get your highlights right. Unless you're lucky or pretty experienced, that means a lot of see-sawing back-and-forth with different high- and low-contrast settings till you get both the highlights you like and overall print contrast that you want. Some of that is unavoidable, but I find I can zero in on that goal more easily with a single, intermediately-filtered exposure.

Best,

Doremus

 

[Pieter12]

That base exposure for highlights that you decide on from the low-contast strip is more than likely not going to be your final exposure time. If you need even moderate amounts of high-contrast exposure, those highlights are going to be affected and you'll have to reduce the base exposure to keep them from becoming too dark/muddy. That means, that when you get the shadows right on the second strip, you'll end up with over-exposed highlights.

On the contrary, because the paper is less sensitive to #5 filter exposure, highlights will most likely not be affected. I regularly burn clouds with a #5 filter to give them more shape. Obviously, that can be overdone and kill the highlights, It is all a matter of degrees.

 

[Doremus Scudder]

On the contrary, because the paper is less sensitive to #5 filter exposure, highlights will most likely not be affected. I regularly burn clouds with a #5 filter to give them more shape. Obviously, that can be overdone and kill the highlights, It is all a matter of degrees.

For the very, very bright areas, this is true, but for, say a Zone VII highlight (think light grey concrete, etc.), even a moderate amount of #5-filter exposure will make a difference. I don't know about you, but I don't base my decision for an overall print exposure on the specular highlights, but rather the Zone VI -VIII range.

There are highlights and there are highlights... It's all a matter of degrees

FWIW, I burn clouds with the highest-contrast setting a lot too.

Doremus

 

[Pieter12]

even a moderate amount of #5-filter exposure will make a difference

For me, I would dodge those areas during the #5 exposure.

 

[Doremus Scudder]

For me, I would dodge those areas during the #5 exposure.

Then you don't get increased shadow density. Better to adjust the base exposure a bit and burn.

Of course, every print presents its own unique problems and solutions are varied.

Best,

Doremus

 

[Pieter12]

Then you don't get increased shadow density. Better to adjust the base exposure a bit and burn.

Of course, every print presents its own unique problems and solutions are varied.

Best,

Doremus

Not intending to be argumentative, and just imagining the situation, but if it is light grey concrete I don't think there would be much shadow intensity to be affected.

 

[Doremus Scudder]

Not intending to be argumentative, and just imagining the situation, but if it is light grey concrete I don't think there would be much shadow intensity to be affected.

Not to be argumentative either But rather, to clarify: When I meter an area of, say, light grey concrete, it has a lot of texture, maybe some dark pebbles, some shadows from the glancing light, etc. In other words, lots of texture defined by micro-dark areas that can deliver a real sense of texture if the contrast is right, even though my meter reading of the larger area tells me it falls on Zone VII or VIII. So, burning with max contrast to get more texture is often a good trick, especially if the rest of the print works at a rather soft contrast setting. But, at least in my experience, burning a lot at the highest-contrast setting will darken the overall density of even lighter-gray areas enough to require some dodging during the initial base exposure. Finding the balance of dodging to burning back then becomes my focus.

Best,

Doremus

 

[Ben wright]

There is already a thread on this topic:

https://www.photrio.com/forum/threads/split-grade-printing-technical-analysis.186517/

Thank you for directing me - very helpful thread

 

[Ben wright]

Thank you for your reply - very helpful advice and sounds promising. Will definitely be trying out some localised test strips during my next darkroom session. Have to admit it never crossed my mind before reading about it recently but makes quite a lot of sense. The same with f-stop printing which i'm keen to try! Have found it difficult with some test strips using incremental timing to choose the optimum exposure time. Sounds like a great set-up!

I've also read that you should do it in reverse when dealing with low contrast or high contrast image. I cannot remember anymore what way it was



I think localized test strips is the only correct way to do test strips. At least it is 10x better. I was struggling with the same issue as you until I found out about LTS method. LTS tool is really easy to make from cardboard.



I have also strong opinion about f-stop printing; that is also the only decent way to print. Everything works in "stops" so why adjust time in seconds? It is really hard to estimate correction in seconds if base time is varying in your negatives, enlarging size etc. Also burning/dodging comes very much intuitive.

I'm using f-stop LED enlarger where all these are combined in same package. No more filter juggling, no more thinking of times. Making test strips for different contrast - easypeasy. Makes printing so much productive and I can concentrate much more on the output.

 

[Ben wright]

Thank you for your very detailed reply Doremus, much appreciated and very helpful. Will certainly explore some of your suggestions here!

An alternative method:

I use split-grade dodging and burning a lot, but like to find a single contrast setting for my base exposure. I find this easier and more economical of both time and paper.

Therefore, a single test strip is made as follows:

1. I guesstimate the contrast I'll need from the proof or from a visual evaluation of the negative. I'll start there. let's say I'm at roughly grade 2.5, or 30M or so on my color head. I make a test strip using a strip of paper, usually a third of a sheet cut lengthwise. I try to place the strip so that the middle of it is in an important highlight in the print (not always easy, but usually doable).

2. I expose the test strip using percentage times (much easier for me than f-stop timing and basically the same thing). I start with a 30% test strip (I've figured the times and have them memorized), which I make by successively covering the strip with a card. For example, I'll start with 10 seconds, then cover the first strip and count 3 seconds (30% of 10), then I'll cover the next stripe and count 4 (3.9 seconds is 30% of 13). Now I've got 17 seconds total, so the next stripe gets 5 seconds (5.1 is 30% of 17). I'll continue with this scheme adding successively longer times as I go. My 30% scheme is: 10-second base exposure and then successively cover strips counting 3, 4, 5, 7, 9, and 11 seconds. That gives me a strip with approximately 30% intervals with the following exposures: 10 sec., 13 sec., 17 sec., 22 sec., 29 sec., 38 sec., and 49 sec. (I like print exposures in the 20-30-second range).

3. After developing and fixing the test strip for a minute or so, I'll turn on the viewing light over the fixer tray and evaluate the strip. I'm simultaneously looking for good highlight tonality and detail (for the basic print exposure) and contrast (since I'll likely have to adjust contrast). If the contrast is way off, I'll adjust the setting on the color head and make a second test strip as above. Usually, however, the contrast is close enough that I can just tweak the setting, say adding or subtracting 10-30 units of whatever filtration I'm using (if you're using filters, that's tweaking a half-grade of filtration or so). Let's say I have a good starting exposure (highlights look good at, say, 22 seconds), but I need more contrast. So, I'll add 20-30M or so and add 10% to the exposure for the additional density and then make a full-sized test print. Yes, the exposure may be slightly off, but my first straight print never gets saved anyway.

4. After processing the first test print, I'll evaluate and make any changes in exposure, contrast, etc. as well as deciding on a scheme for manipulations. Here's where the split-grade part comes in (when needed - often it isn't). If I need a lot more contrast in a certain area of the print, I'll first try burning with the highest-contrast filtration. If that overexposes the area, then I'll hold it back during the base exposure and then burn back with the high-contrast filtration. For areas that need lower contrast, I'll dodge during the basic exposure and burn back with the lowest-contrast filtration. Finding the proportion between base exposure, dodging and burning back is the trick here. For areas that are overly-contrasty and don't have highlight detail, I'll just burn a bit with the lowest contrast filter if I want to keep the other values as they are. Plus, I can always burn with the basic filtration too. Lots of possibilities here.

But we're way past making test strips here... Notice I usually only make one or two test strips before moving on to the first straight print. I imagine I could make one test strip, process it, change contrast settings on my enlarger and make a second in about the same time as it takes to make the strip with exposures from both settings. And, I often only need to make the first strip.

Les McLean's method works too, but isn't exactly accurate in terms of final exposure either. That base exposure for highlights that you decide on from the low-contast strip is more than likely not going to be your final exposure time. If you need even moderate amounts of high-contrast exposure, those highlights are going to be affected and you'll have to reduce the base exposure to keep them from becoming too dark/muddy. That means, that when you get the shadows right on the second strip, you'll end up with over-exposed highlights. You could reduce the basic exposure and make yet another strip, or even as a general rule, reduce the basic exposure before making the second strip by 10% or a bit more. Still, fine-tuning the low-contrast overall print exposure is probably going to be necessary to get your highlights right. Unless you're lucky or pretty experienced, that means a lot of see-sawing back-and-forth with different high- and low-contrast settings till you get both the highlights you like and overall print contrast that you want. Some of that is unavoidable, but I find I can zero in on that goal more easily with a single, intermediately-filtered exposure.

Best,

Doremus