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Contrast filters and midtones

Ariston

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I am trying to learn how to use contrast filters and am having a difficult time. Both Grade 5 and Grade 00 filters seem to impact the mid-tones so much that I have a hard time adjusting the highlights and shadows without dramatically changing the rest.

I know that a big part of the benefit is being able to selectively burn the highlights or shadows, but if it is impacting the mid-tones this dramatically, is it really being selective at all?

Can someone tell me how I should expect contrast filters to affect the mid-tones?
 
I think you may be misunderstanding how the filters and the emulsion components interact.
All filters affect all tones - they just tend to affect them in differing amounts.
How are you approaching the making of test strips with, for example, a negative with a range of tones?
 
Without knowing a whole lot more specifics about what you're doing or not doing, it's impossible to give a simple generic answer. But if your technique is dialed in, your midtones should look wonderful without sacrificing the quality of either the shadows or highlights. My hunch is that you're overdoing the follow-up burn-in exposures.
 
I've been practicing with the negative of a classic car that I mentioned on the other thread. I read the link you provided, then also tried your suggestion of starting with the shadows (5 filter) first, because I had a black tire with some texture and a completely Zone 0 wheel well.

I used test strips on that part of the photo to arrive at an exposure time of six seconds (I could stretch that out, but I am having no trouble with the time so far). I then exposed a full strip for six seconds on Grade 5, then added 2 second intervals with Grade 00. The Grade 00 filter darkened the paint on the car so much that I couldn't really choose a time based on how it affected the highlights - it would darken the paint too much. I had to stop at two seconds. I guess I could stretch the overall exposure out with a smaller aperture, but I don't know if that will give me what I'm looking for.

I can work with all this if I know what to expect in the mid-tones, but it also feels like I am not going to have as much control as I thought.
 
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I generally only start with the grade 5 filter if I am working with a predominantly bright and light subject, with only small areas of dark image. Something that might be referred to as high key.
Shots taken in bright fog are a good example.
 
Using a condenser enlarger and plain Ilford filters inside a filter tray, since the mid-nineties when we lost graded paper, I have never used the 00 filter and seldom the grade 5 filter. I print up to 20X24 in. and I like my prints to have more than less contrast. I am less interested in showing all the details.

To me, what your describe sounds like over-complicating things while perhaps (but in this I could be wrong) you still need to learn basic printing. My advise would be to make straight prints for some years, without changing filters once you found the correct filter for the whole image, until you really master that. By repeating the process over and over, and meeting different problems as they will inevitably come, that's how you become a good printer. And that's when printing becomes a pleasure.
 
Both exposures do impact mid-tones. How else would we get any mid-tones? The hard exposure has more impact on lower mid-tones, the soft one more on the upper mid-tones. If the mid-tones don't fall into place as you want them when you adjust for highlights and shadows, you have a difficult negative, and the means to work it out are dodging and burning, bleaching and flashing. Advanced stuff. I suggest you try a different negative for now, shiny objects like cars often make for difficult negatives.
 
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Thank you everyone. I am working on the basics, and have that down pretty well as far as finding the right exposure. I can get a negative that is good enough using just the 2.5 filter.

I am not trying to print something amazing (it's not even a remotely good photo) - I chose this image specifically for PRACTICE only. And I chose to do the 5 filter first because I wanted to practice separating some dark tones. I will practice on another negative to practice separating light tones.

Am I wrong to start with the the 5 filter if those are the tones I think need to be addressed most? The rest of the image is easy enough. It is actually a pretty well defined negative other than the tones I am purposely working on.

It will be hard to tell on this photo, but the negative shows that there are different tones for the tire and the wheel well. I was practicing trying to get some separation there:

 
As someone has said before, in this situation you need to expose your test strips with the chosen 00 exposure first, then work out the 5 exposure. Otherwise the small impact the 00 exposure has also in the dark tones will further darken the shadows beyond what you wanted. In what order you expose the final print makes no difference.
 
That is the problem with split-grade printing - you lose direct control of the midtones, which is where an image's interest lies.

If you have a complete set of contrast filters then try making test strips of just the midtones with a #2.5 filter. Make a full print. If you want more midtone contrast repeat with a #3, if less then try a #2. After you get the midtones where you want them then burn and dodge to modify the shadows and highlights as needed.

A general bit of advice - VC papers have their best midtone response at grades #2.5 - #5. At lower contrast grades the midtones will lose contrast. The ideal negative for VC papers has full detail but is rather thin and low contrast. A good rule of thumb is to expose at 1/2-2/3 of box speed (rate a 400 speed film at 250-200) and develop for 15-20% less than the developer/film data sheet says. Film makers like to claim the highest speed they can; in the late 50's they doubled film speeds across the board and so the standard regime they recommend can be cynically thought of as a "1-stop push."

The "expose more, develop less" regime is the conclusion most photographers reach after they go through 2 weeks of "zone system" testing to find their "personal film speed" and "personal development time." Not that going through the testing is a bad idea: the benefit is the insight you get from the exercise rather than its outcome, a bit like an experiment in chemistry class where the outcome is already known but you do the experiment to learn.

If you want to continue with split grade printing you need to use two methods:
  • If the negative is low contrast then you should determine the #5 exposure first using the black point, then give the overall #5 exposure and make a test strip with the #00 filter to find the white point exposure;
  • If the negative is high contrast then you should determine the #00 exposure first using the white point, then give the overall #00 exposure and make a test strip with the #5 filter to find the black point exposure.
Advice from people who swear by one or the other do so because they commonly produce high contrast or low contrast negatives - and so both bits of advice are valid, just that you need to switch from the one to the other as needs must.

A rather technical paper on split grade printing is available at Darkroom Automation's web site http://www.darkroomautomation.com/support/appnotesgmeasured.pdf. The paper is directed to user's of DA's enlarging meter but it gives a general discussion of the black-first Vs. white-first reasoning.

Another paper you might find interesting is http://www.darkroomautomation.com/support/appnotevcworkings.pdf which explains why low contrast VC filtration results in a flat-spot in the mid-tone contrast.
 
When you say that the 5 filter tones need to be addressed most, what do you mean? What was your criteria for determining the 5 filter exposure? And when you printed this, did you do any dodging or burning with either filter?
 
Have you tried trying to achieve your best print by just exposure control without using any contrast filtration? You would then have a reference point to experiment with contrast filters.
 
Listen to Nicholas
Here is an example of an image where I would start with the #5 filter:



For your test image, I would start with the 00 filter if I was using split grade.
When you have achieved the print you want with split grade techniques, try printing two more prints from the same negative, without changing any settings - one print with just the 00 filter - same exposure time as in the finished print - and then another print with just the 5 filter - same exposure time as in the finished print.
I predict you will be amazed at how much of the final image comes from the 00 exposure, and how little comes from the 5 exposure.
Remember, contrast is created by adding density on top of density, not by one filter doing one thing, and the other filter doing another.
(PS that example is a bit of a fudge, because it is actually from a colour negative. I didn't have a good black and white example digitized and close at hand).
 
I have heard it said that what ever is achieved with split -grade printing can be better achieved using the proper single grade filter in the fist place.
 
Arthurwg said:
I have heard it said that what ever is achieved with split -grade printing can be better achieved using the proper single grade filter in the fist place.
Click to expand...
If you don't burn and/or dodge your prints, you can come very close to the same results with single filters, and can achieve exactly the same results with a single setting on a colour or variable contrast light source.
If you selectively burn and/or dodge specific areas in your prints, and customize the contrast settings for those burns and dodges, you can do more with split grade printing.
 
As many of the people on this site are very experienced printers, it would be helpful if any OP for printing/dev/process enquiries stated when they started. Otherwise they may be completely confused by replies.
 

Thank you, Nicholas. This is a lot of good information that I need.



Pieter12 said:
When you say that the 5 filter tones need to be addressed most, what do you mean? What was your criteria for determining the 5 filter exposure? And when you printed this, did you do any dodging or burning with either filter?
Click to expand...
No dodging or burning on this one yet. It was my understanding that the 5 filter affects the darker tones more, so I was trying to dial it in to achieve some separation of two dark adjacent tones: The tire and the wheel well. This is specifically what I was trying to learn and practice with this negative.

I am trying to learn how the filters affect each of the tones and how best to get well defined tones BEFORE I dodge and/or burn. Seeing that the filters affect the mid tones so dramatically gives me concern about dodging and burning with them when I start practicing that.
 
cliveh said:
As many of the people on this site are very experienced printers, it would be helpful if any OP for printing/dev/process enquiries stated when they started. Otherwise they may be completely confused by replies.
Click to expand...
Do you mean how long I’ve been printing? Maybe three sessions so far.
 

Nicholas,

I'm quoting your entire post simply because it needs repeating. A breath of fresh air, as always. Thanks,

FWIW, since I switched to printing primarily on VC papers, I've had to reduce my development time and print at a higher contrast setting (I like to aim for about 3.5 now) in order to get decent prints. Still, I miss the highlight separation that one got from premium graded papers in the past (Seagull G, etc.). VC papers seem to have about the same toe and shoulder regardless of the contrast filtration used. Thank God for potassium ferricyanide

As an aside, I've also noticed that my VC prints seem to tone better, i.e., more evenly and with less split-toning, when made at higher-contrast filtration settings.


@OP,

Do take Nicholas' advice and make some prints with a single filtration instead of split printing. You may find, like I do, that starting with a filtration that gets the mid tones where you want them and then burning with the #5 or #0 filters works better. In your example, I might first find the filtration that gives you the tonalities and the separation in the mids on the paint and body and then maybe burn the tires with the #5, etc.

Best,

Doremus
 
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Ariston said:
Do you mean how long I’ve been printing? Maybe three sessions so far.
Click to expand...

Then you should ignore every reply thus far and concentrate on printing with no filtration at the correct enlarger exposure.
 
Nicholas Lindan said:
...VC papers have their best midtone response at grades #2.5 - #5. At lower contrast grades the midtones will lose contrast.
Click to expand...

Hmpf, quoting my own post, yet another sign of incipient senility.

I should add that with lower contrast grades all the reduction in contrast comes out of the midtones. The highlight and shadow contrast don't change much. Highlight and shadow contrast don't increase until you hit filters 3.5 - 5.

Again see http://www.darkroomautomation.com/support/appnotevcworkings.pdf for the whys and wherefores.
 
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cliveh said:
Then you should ignore every reply thus far and concentrate on printing with no filtration at the correct enlarger exposure.
Click to expand...

Seconded. Though there is some benefit to sticking with a #2 1/2 filter.

Get into split filter after you have mastered 'no filter.'
 
MattKing said:
I generally only start with the grade 5 filter if I am working with a predominantly bright and light subject, with only small areas of dark image. Something that might be referred to as high key.
Shots taken in bright fog are a good example.
Click to expand...

I may print a 2 first but I usually do what you are doing from the start. I just gets me there faster.
 
I printed for years before I started doing selective split-grade printing. I have negatives that would not be possible to print to my liking without it.
The technique you're using will not necessarily help in many situations and is not a magic fix. Using split-grade of the overall image will impact the mid-tones, as some here have already stated.
I'd try getting a satisfactory straight print between grade 2 and 3 first, with the midtones exactly where you want them. If the darks in the area of the tire and wheelwell are still blocked-up and you need more separation, try dodging that area during the main exposure. If that area starts to look too muddy, back off a bit. If you still can't get any tonal separation, that area on the negative may be too underexposed to show any detail.
Also, if you lose any highlight detail in the reflections on the bumper and wheel, you can try selectively burning-in those areas with a grade 0 filter.
There's tons of different techniques to get where you want, so don't get frustrated after only 3 sessions. I've taken weeks or months to get some negatives to print the way I want.
When you make a breakthrough in the darkroom, it's a great feeling!
 
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