Split Filter printing article in "Photo Techniques"

[markbau]

Thanks to everyone for their replies.

I'd just like to clarify. Are you using split filter printing because you are printing with the ilford or Kodak filters and split filter allows you to get in between the grades of the filters?

When I start printing again it will be with a colour head so am I right in assuming that the issue of split filter printing is a moot point when using a colour head as any degree of contrast is available with a colour head.

Mark

 

[cowanw]

No and yes and no
Your new question is going to start the discussion all over again.
I do both.
But my principle theoretical problem with the colour head is the infinitely variable choices that can be made.
I use the combined, constant time settings for kodak colour heads and I know these give different results for my two enlargers. LPL and Omega.
No matter, it is the print that is the point.
But if I want a little more or less contrast, do I add or subtract yellow or magenta or both and do my times stay the same? I don't know; just too many choices and too little time to test them all.
Split filtering at least limits my choices of filter values to two, all yellow and all magenta.
Burning and dodging aside, I am sure there is always a dichroic combo that would match. Scientifically there has to be. The question is finding it.
I use both methods but use the split filtering on the dichroic heads when I get too confused over a print.
Everybody eventually settles on a technique that suits their brains.
You have to find yours.

 

[Mahler_one]

Thanks to all for the very instructive and interesting comments regarding SG printing.

Ed

 

[Shawn Dougherty]

I use a color head to do my split grade printing.

If you want to use single grades you'll need to calibrate your head (to keep your exposures the same through out the different grades). Check out this article by Paul Butzi. Hope this helps. All the best. Shawn

 

[Photo Engineer]

In the workshop I took a few years ago from Dave Vestal and Al Weber, they had us use split filtration while printing. We were required to expose some shots with extremes of shadow and highlight with high lighting ratios and then print straight, print split and print with dodging and burning.

The results were in the improving order, straight, straight d&b, split grade, split d&b. There is no question in my mind that split grade improves the quality of some prints and adding in some d&b gives even more control.

PE

 

[srs5694]

When I start printing again it will be with a colour head so am I right in assuming that the issue of split filter printing is a moot point when using a colour head as any degree of contrast is available with a colour head.

It's not really a question of getting a particular contrast. Think about it this way: VC papers produce different contrast by adjusting the amount of green vs. blue light that hits the paper. (Magenta and yellow filters just remove green and blue light, respectively; red light is irrelevant to the equation.) Whether you do this by using a single exposure and a filter that lets through blue and green in a particular proportion all at once; or by doing two exposures, one for blue and one for green, is immaterial. You get the same result either way. (This analysis ignores dodging and burning issues, which might require something akin to split-grade printing if you want to adjust contrast in one part of the print.)

The main difference is one of the process -- how easy is it to get the print you want using split-grade vs. conventional VC printing? This is more an issue of psychology than it is of physics or chemistry -- how do you learn, how do you perceive, how do you solve problems? Many of the posts in this thread have reflected this, but I want to make the point very explicit: It's about psychology. This is just a matter of personal preference or idiosyncracies of how different people think or work in the darkroom.

My advice: Try both methods. Decide which one you prefer. Use it, but understand its advantages and disadvantages, and be prepared to use the other method if you think it might be superior for a particular print.

 

[ChuckP]

Phil Davis also did an article in Photo Techniques a few years back showing that the same straight print (no dodging and burning) results can be had from a single exposure or split grade exposure. I haven't found any explanation yet why two exposures using split grade cannot be matched using a single exposure through the proper filter. Maybe there is something going on in the paper thresholds that would make a split grade curve different Some people seem to see it.

 

[Photo Engineer]

Well, one part of the image can be at grade 0 and another can be at 4. That should give you an idea of what is going on.

PE

 

[dancqu]

VC papers produce different contrast by adjusting the
amount of green vs. blue light that hits the paper.

So, the lens should be very well corrected for longitudinal
chromatic aberration. Difficulties in printing as sharp an
image as is possible are introduced when two colors
must form the image in the exact same plain.

I suppose a valid test of one's lens would be to focus with
one color then make a print with that color and then make
a print with the other color. The prints are needed because
in most cases the light by which one focuses is not the
same as the paper's range of sensitivity.

Longitudinal chromatic aberration is not so much an issue
with Graded papers. That is as long as they are blue band
only sensitive. Some of the better more expensive grain
focusers are equipped with a deep BLUE filter. Dan

 

[ChuckP]

Well, one part of the image can be at grade 0 and another can be at 4. That should give you an idea of what is going on.

PE

Without dodging or burning? How does that work?

 

[Photo Engineer]

Without dodging or burning you will get an overall high contrast and low contrast image by exposing in the proper sequence of filtration. But, that is why dodging and burning in my original post + split filtration got the highest marks for improvement. So it works either way but without D&B you need to be very careful and the negative must be usable this way.

PE

 

[markbau]

In the workshop I took a few years ago from Dave Vestal and Al Weber, they had us use split filtration while printing. We were required to expose some shots with extremes of shadow and highlight with high lighting ratios and then print straight, print split and print with dodging and burning.

The results were in the improving order, straight, straight d&b, split grade, split d&b. There is no question in my mind that split grade improves the quality of some prints and adding in some d&b gives even more control.

PE

The only writing by David Vestal I've seen on the subject suggests he only sees any value in split printing as a way of getting in between grades when using Kodak or Ilford filters. The reason for my original question was that when I stopped printing, about 10 years ago there was a growing number of printers extolling the virtues of split filter printing, they claimed that prints made this way exhibited qualities not attainable by normal methods. This was at a time when we had just been through the Fred Picker cold light nonsense, (he made similar claims about cold light) Many people were quite skeptical of the split filter claims. I tried it and found no difference with the two methods but as I was using a colour head I found that the split filter procedure was very time consuming for the same results compared to printing with a single exposure on a colour head. It appears from this thread that some people are still claiming split filter printing produces results not attainable using just a single exposure. Photo Techniques is a widely respected magazine and if they are saying split filter printing produces the same curves as straight printing I find no reason to doubt them, as another poster said, Phil Davis came to the same conclusion. Howard Bond is pretty damn good printer too and he says the same thing. But of course I'm always on the lookout for procedures that might improve my work now that I'm getting back into B&W printing.

Thanks for everyones responses

Mark

 

[Photo Engineer]

Well Mark, I know what my eyes saw and I have a photo of myself and David examining one of the prints. I have gone through the sensitometry on paper and it makes sense and works out diagramatically on graph paper as well. Dave and Al taught that in the Workshop, and I believe it even though I do not use it much myself.

PE

 

[jeroldharter]

Split filter printing is a great way to go. Especially with a difficult negative or if your negatives are inconsistent (whose are too consistent?).

However, it is time consuming and tends to use more paper. I have had printing sequences with a flash, two base exposures, and 8 burns at different filtrations. That works OK but is not very pleasurable to me.

Using BTZS methods results in more consistent negatives and less need for split filter printing. However, having done a lot of split filter printing, I think I am able to print better in the usual mode but with selective dodges and burns. I other words the post-visualization is better.

I think it is great that people get "emotional" about straight or split filter printing. Isn't the darkroom great?

 

[Nicholas Lindan]

I think it is great that people get "emotional" about straight or split filter printing.

I have observed that emotions step in to fill the void when thinking and demonstrable evidence are lacking.

Aggressive emotions also come to the fore when one's ideas and beliefs are attacked. An attack on one's beliefs is an attack on oneself.

No wonder so many wars are over religion.

 

[panastasia]

With a cold light head and a standard set of VC filters I couldn't get a satisfying print from a particularly difficult negative using one filter no mater how I tried. When I tried the split-grade method there seemed to be some improvement, but not much. My color head didn't do any better. I gave it one more try with a different split-grade system/method using a low contrast green #58 wratten filter and a high contrast #47B wratten filter and ended by making a satisfying print of the difficult negative. Now, was the reason for my success due to the green & blue filters working better with the spectral output (energy wavelength) of my cold light, or was it the split-grade method? I believe it was a combination of both. One thing I'm absolutely sure of is that I couldn't get the job done with one standard VC filter. Another thing I learned long ago is not to believe everything I read in magazines and newspapers.

I'm sure someone will think that if I had a full set of green & blue filters I could have found the single filter that would do the same thing. Maybe, but that set doesn't exist. So, what now? It's just another debate that can go on for years.

 

[Nick Zentena]

I found that the split filter procedure was very time consuming

I never found this. Two test prints and I've got exposure and contrast.

 

[markbau]

Well Mark, I know what my eyes saw and I have a photo of myself and David examining one of the prints. I have gone through the sensitometry on paper and it makes sense and works out diagramatically on graph paper as well. Dave and Al taught that in the Workshop, and I believe it even though I do not use it much myself.

PE

I take it that you disagree with the H&D curves published in the Jan/Feb issue of Photo Techniques where the authours showed there was no difference in the curves? I'm not trying to start an argument here but in photography, like in life, there are facts and their are beliefs. I'm just trying to find out the facts about split filter printing.

 

[markbau]

. So, what now? It's just another debate that can go on for years.

We are not talking about mystical thoughts here, but rather things that can be tested and proven or disproven. It shouldn't be debatable, it either does produce a curve that is not attainable with a single filter or it doesn't. If printing with 2 filters is a more convenient/logical way for some printers that's great but it is not the issue here.

 

[dancqu]

I take it from reading of many posts that
split filter printing is a LOCAL contrast
control method. Applied GLOBALLY it
it will deliver the same curve as
a same blend of filters.

So or not so? Dan

 

[Photo Engineer]

I take it that you disagree with the H&D curves published in the Jan/Feb issue of Photo Techniques where the authours showed there was no difference in the curves? I'm not trying to start an argument here but in photography, like in life, there are facts and their are beliefs. I'm just trying to find out the facts about split filter printing.

Dan is correct. It is a local effect and applied to the entire sensitometric strip will give the blended filter contrast.

And this is how you (and the authors) can be fooled. You don't make sensitometric scales, you make pictures!

I did not read the article, but I did do the work making real prints.

PE

 

[panastasia]

We are not talking about mystical thoughts here, but rather things that can be tested and proven or disproven. It shouldn't be debatable, it either does produce a curve that is not attainable with a single filter or it doesn't. If printing with 2 filters is a more convenient/logical way for some printers that's great but it is not the issue here.

Is split filter printing buried as an idea or do some people still use it? Quoted from your first post.

I simply answered your question and gave a reason why I still use it. I didn't think it was a matter of convenience, or logic, it was a different method to use - a different tool in the tool box. I saw a difference in the results and that's what mattered. Are you asking a loaded question so you could educate some of us "who still use it?" I think you made your point - it's all about curves. Whether split-grade printing has a value or not, is debatable. And what's with the "mystical thoughts", where's that coming from?

 

[dancqu]

So, what now? It's just another debate that can go on for years.

Not necessarily. But we have not complete information.
In what way were your first results poor and how did the
two attempts at improvement show their results. Dan

 

[David Brown]

The Jan/Feb 2009 issue of Photo Techniques" has an article that investigates if it is worthwhile to print VC paper by exposing the paper to both a high contrast and a low contrast filter versus exposing the paper to a single filter of the required contrast. In a nutshell the article says that in the case of people with a colour head split filter printing achieves nothing. ...

I am constantly amused at how this issue always quickly becomes one of passion, rather than reason.

I quoted the original post to more or less steer the thread back on track.

Does split grade with a color head achieve nothing? Yes. No. Maybe. SG is a technique. It is not a revolution. I had the same experience that the authors of the cited article had (before I read the article BTW). I took a SP workshop with one of the best practitioners (McLean) and am friends with a competent printer who uses the technique exclusively. I bought the RH Designs Stop Clock to use for F Stop printing (another passionate debate).

Using the 2 channels of the Stop Clock for the two exposures (hard and soft) one can get to the desired contrast. At that point, one can press the right button on that magic machine and it will tell you the effective grade that the two exposures will yield. If I (read: "I") then make another print at that computed grade, it looks the same to me.

Obviously, this is subjective and there are many other variables in equipment, materials, and (of course) the skill and "eye" of the printer.

Then, dodging and burning at different grades adds another diminision. One can D&B at different grades while using SG or a single grade. It's hard to compare results with all those variables. How about if I flash the paper first?

So, to the next question in this thread: "Does SG give you different/better/easier prints that single grade? Maybe. Maybe not.

It is a technique. It is not for everybody. One must try it to decide if it fits their needs, or does not. There are IMHO way too many variables for a pat answer.

YMMV

 

[panastasia]

Not necessarily. But we have not complete information.
In what way were your first results poor and how did the
two attempts at improvement show their results. Dan

Dan,
"The devil's in the details". It sounds like a cop out, but I'm not interested in debating. Something worked for me - that was my objective - my eyes don't deceive me. I could see an overall improvement in the final print, perhaps because I was using extreme filtration. No change in the developing process and I, generally, don't concern myself with theory, or matching curves. Although, I find there's some interest in those aspects when comparing new products.

Paul