Ensuring pure black (D-max) in a print

banandrew

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Hi everyone, I've been experimenting in the darkroom the last couple of months, basically whenever I can find the time (6-8 hrs/day, 2 days/week) making work prints from my backlog of negatives. The last couple of weeks I've been finding that I am not consistently getting D-max in my prints, and I'm not sure of a process/workflow that will get me there. So a couple of questions for this knowledgeable community:

1) is D-max something I should strive for in every print? Obviously not every print would be a candidate for it, so I'm ignoring those (e.g. a photo of a scene without deep shadow, or a gray card).

2) If I make test strips with detailed shadows in mind, the print often ends up too light, lacking pure black (D-max), however

3) When I make my test strips, if I pick an area I *think* should hit D-max and test-strip for it, I usually end up with a print that is too heavy. Is this an issue with choosing the wrong type of test strip? Is this a good way to get D-max? For instance I could still hit D-max by printing longer, so the minimum time for black is not really a good way to check.

4) Should I just not worry about it for straight prints and then get the D-max by burning in, e.g. with a #5 filter?

thanks everyone, I've spent the last 4 or 5 printing days trying different methods with pure black in mind, and so I thought I'd turn to the community for assistance.

aside, in case this information is relevant:
I've tried a few different work flows for the straight/base print, including the "basic printing" method described in Way Beyond Monochrome, as well as split grade printing (with #00 and #5); right now my preferred method is single grade for the straight print, where I test-strip to include important highlight + shadows, and use the information to determine the required change in contrast. (I don't know if there's a name for my preferred method, as it's a variation of one I found on youtube, and not described in Way Beyond Monochrome, my only text on darkroom printing besides "The Print"). Also, ever since I started making proper proof sheets, it's been MUCH easier to find the base print time+contrast, but still sometimes I find I don't hit pure black. I'm looking for a consistent method to do it.
 

bernard_L

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is D-max something I should strive for in every print?
If I make test strips with detailed shadows in mind, the print often ends up too light, lacking pure black (D-max), however

Answer to question (first line above): IMO, no; at least not generally.
And you have outlined the reason yourself on the second quoted line. Reason: Dmax is at the very end of the D/logE curve, where the contrast (separation) goes to zero. Of course, there are situations wher you might want max black: a large featureless area looks better full black than murky dark gray.

And, same applies to highlights, if you value separation.
 

RalphLambrecht

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I don't think it's an absolute necessity but I do try to get Dmin and Dmax into every print because I fell it gives the print some brilliance. Taht's why I always print with a reflection desitometer near by; Sounds like OTT but it helps me a lot to get optimum base exposure and contrast right.
 

Роберт

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Fresh chemicals is always a good idea to start. Further I am sometimes measuring back in reflection with my TRDZ densitometer to check the result. For the rest: See above remarks.
 

RobC

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there is balance to be found which is a combination of having the right personal film speed (ISO box speed is the best starting point), the correct exposure and film development and then the correct print time and paper contrast setting.
If your negatives are properly exposed and developed then obtaining a good black should not be difficult.

Contrast settings on an enlarger should have a "speeed point" which is where all the contrast curves cross. This "speed point" is the point where a particular negative density will produce the same print tone with all the different contrastt settings. See graph below.

You will see that for these filters and this (no longer available) paper that each contrast filter crosses at a log of print density of close to 0.3 which is highlight value. This crossover is the "speed point". If you know roughly which print tone will be the speed point for your enlargers filters, then you use that speed point tone to set your print time when making a print and NOT a Dmax tone.
The procedure is to pick a highlight tone in the neg and produce a test strip through that part of neg and adjust print time until that print tone is about right in the test strip. Then, and only then, you adjust contrast settings to get towards a DMax and Dmin in your print and that speed point tone should stay about the same as you adjust contrast.
Easy said but can be tricky depending on your enlarger and filters. Ilford MG filters are a known constant, are extremely well balanced for speed point and have a speed point which is on a highlight tone. Dichroic colour head filters are an unknown quantity. They may be well adjusted or they may not. The paper manufacturers quote combined Y+M figues to use but they don't tell you what tone the speed point is on. My Durst L1200 is extremely well suited to Ilford papers and the dichroic filters poduce a speed point on a print density of approx 0.7, so a mid tone and not a highlight like the Ilford filters use. When I print using dichoric filters I do a test strip on a mid tone and then adjust contrast around that tone.



Notes:
Often the contrast curves don't all cross at the same point but they are usually close(ish) but not always.
As paper ages it loses some of its contrast. This results in the contrast curves above swinging down (leaning over to the right) and that moves the speed point down to lighter print tone, especially where the speed point was a midtone on fresh paper. This means it ain't as fixed as you might like it to be so you always need to assess where it is for any paper/filter/paper dev combination as you print.
You may not have the speed point tone in your neg/print so you can't assess it accurately and infact its extremely hard to asses it by eye anyway. So be aware that its a ball park assessment only but that is all that is required. Your final tweaking of a print is always by eye and is always a combination print time and contrast setting. You must obtain this skill through practice.

So to summarise: The print time should be set on the speed point tone. If that is too dark then your print time is too long. If its too light then print time is too short. Then once that tone is about right, you adjust contrast settings to get the blacks you want. Start at G2 setting for print time and then adjust contrast from there.

Do not try and set correct print time on a shadow or black.

Setting print time on black is only useful for determining film speed and even then I wouldn't be aiming for max black becasue paper will print blacker, if you over expose it, than you can print it in a normal print.

How do you find the speed point? It will usually be somewhere between 0.3 and 0.7 print density. i.e. between a highlight and mid tone. You'll soon get a feel for it once you start looking for it when you adjust contrast. i.e. looking for which print tone moves the least when you adjust contrast. That will be on or close to speed point.

If you are using only Y or only M settings then you always need to adjust print time when you change contrast.

Finally the speed point ain't an exact science. It will move about as mentioned above and also depending on print developer exhaustion but providing you know roughly where it is, then can get an approx print time which you then tweak as you adjust contrast.

test strips are your friend.
 
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Sirius Glass

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If one prints every print to have Dmax, many of the prints will be too dark to be useful. As with all things moderation for everything including moderation for moderation.
 

Oren Grad

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3) When I make my test strips, if I pick an area I *think* should hit D-max and test-strip for it, I usually end up with a print that is too heavy. Is this an issue with choosing the wrong type of test strip?

It's possible that the characteristic curve of the paper you're using is not a good match to the characteristic curve of your negatives, and that you'd be better off with a different paper. What film(s) and paper are you using?
 

RobC

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It's possible that the characteristic curve of the paper you're using is not a good match to the characteristic curve of your negatives, and that you'd be better off with a different paper. What film(s) and paper are you using?

+1

But you must be setting print time on or close to contrast filter "speeed point" if using VC paper otherwise you will be over or under exsposing paper. And over exposing will kill contrast, especially in the shadows which blocks them up even with a small amount of print over exposure. (some people seem to stylise their prints by doing this. Intentionally or not I don't know.)
i.e. you use speed point to set print time and contrast filters to set blacks and whites. Then if neg is giving you what you want then a different paper may be better suited but you can always resort to localised burning in.
 
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markbarendt

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Should I just not worry about it for straight prints and then get the D-max by burning in, e.g. with a #5 filter?

I try to target my print exposure placement based on my main subject matter; typically the meat of a photo is in the middle tones. For me this main subject matter has to fall, be placed properly before anything else. That might be a face or a flower, doesn't matter, whatever it is becomes the anchor point around which everything else gets adjusted. (Yes, sometimes I move the anchor a bit as the rest of the photo comes together.

Next I'll adjust paper contrast if needed to get the contrast rate where I like it. This step tends to get the D-max and D-min darn close, or ever just right.

Next I'll burn and dodge to fix the shadows or highlights or move something in the middle one way or another.
 

gone

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Test strips (of the same paper you print on) for light and dark, filters for contrast (deep blacks). You won't get good blacks w/o the right paper, so sometimes switching to a good fiber paper will help. I really like the Adox MCC 110 papers. You're going to have to spend some time dodging and burning most prints for optimal results, but just having a good paper w/ the right contrast will work on well exposed negs. On underexposed, flat negs, you just do what you can.
 
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banandrew

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Wow, I put that comment in late last night and came back to some really great responses, thanks everyone for taking the time to comment! I really appreciate all your advice. Also, kind of gushing a little that Ralph is on this thread.

Sounds like the gist of it is: whether or not D-max (or D-min) is in the print is a bit of personal preference/style. For example I was looking through Koudelka: Exiles last night and realized he always has D-max in that book, but very rarely D-min. (Also I realize that it's not silver-gelatin, so the process is different, but still, it's about final outcome).

@Oren Grad: I did not consider that at all, but that makes a lot of sense that they should be matched. I shoot almost exclusively HP5+ 135 and 120, and use exclusively Ilford MGIV RC Pearl, so I'm guessing it's probably OK.

@Po6epT: that's interesting, because to conserve chemicals I've been using my developer over 2 days in a row, bottling it in an air-tight container when it's not in use. I've been wondering lately if that's affecting the contrast. I usually check the amount of time (seconds) that any tone starts to make an appearance, and then the 2nd day, as that time gets longer, I increase development time. EG on day 1, if it takes 9 seconds for the first tone to begin to appear, and I dev for 90 seconds, then on day 2, if it takes 12 seconds to appear, then I dev for about 120 seconds. I'm unsure of how much this affects the print, because even if I leave a piece of paper in there for 5 minutes, it doesn't seem to make much difference. I'm still able to get D-max but I wonder if this would affect getting consistent results.

@RobC: thanks for taking the time to make that huuuuuuge post, I really appreciate that effort. I'm not really a fan of that method (choose a highlight close to the speed point and then adjust contrast to affect the blacks). I tried it for quite some time and found a few things I don't like about it, some of which you mentioned: a) it's hard to pick the right highlight tone by eye (I don't have a densitometer to use), and sometimes the speed-point doesn't even appear in the print; b) it's not easy to test-strip the different contrast filters, eg a test strip with same exposure time, but with contrast grade #1, #2, #3. The second point is the main reason for me. So I don't use that method because we just don't get along. It ends up taking me way too much time and test strips to get a decent working print when I work that way. If I ever get a densitometer then I may try it again.

@markbarndt: That sounds like something that might work for me. Sometimes when I make a print depending on highlights/shadows, if the test strip does not include the subject (which is intended to fall somewhere in the mid-tones), then that subject ends up being too light or too dark. I'll try your method and see how I like it.
 

RobC

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So I don't use that method because we just don't get along. It ends up taking me way too much time and test strips to get a decent working print when I work that way.

Sounds like you are not getting along with your new method either.

FACT : If you are getting it right you should be able to take any neg, do one test strip and get a good quality work print. If you are having problems it's because you are getting it wrong. That means your negs aren't right or your printing is wrong.

So some questions:

How do you do your film exposure metering?
Have you done any kind of testing for film exposure such as personal film speed tests and if so detail your process?
What print filtering method do you use? Ilford filters or dichroic colour head filters? If its the latter have you done any kind of testing to ascertain the speed point of those filters? I so detail what you did. Also how do you apply those filters, Y+M or only Y or only M?

We need this information to work out where you are going wrong. Printing a good quality work print is very easy if you're doing it right.
 

MattKing

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Bob Carnie has a number of helpful posts here on APUG that address printing, and given that he does it for a living, he probably has just a bit of experience with it .

One thing that he does - and I'll try to paraphrase this accurately - is effectively deal with the dMax and dMin issues separately from the rest of the print.

He makes his tests and decides on choice of overall contrast and most of the burning and dodging with an eye to maximizing the qualities of the mid-tones and other detail revealing tones in the print. To achieve more impactful blacks, and more detailed highlights, he then adds small amounts of high contrast filter burns in both of those areas. Finally, he often bleaches back slightly the result (to add sparkle).
 

RobC

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But you still have to establish a base print time. Where you take it from there with burning and dodging at whatever grade is secondary to the base print time.

He could try split grade printing but I maintain that if you can't get a decent quality work print from any neg which is reasonably well exposed and developed then you are still on the toe of the learning curve and if you're switching techniques becasue you haven't mastered the basics then you are magic bullet chasing.
 

MattKing

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I agree with the first part of what you are saying.

The think the essence of what I was saying is that for almost all negatives it is important not to let dMax and dMin considerations overly influence your printing choices. Use whatever technique works for you to get a good quality "work" print, and then you can "tweak" the deep shadows and bright highlights to add impact.
 
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banandrew

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Hi Matt, thanks for this, this is the response I was looking for. Maybe I wasn't totally clear in the original post. Right now I'm fairly happy with my current method because it is fast and intuitive. Typically with 1 test strip, and sometimes 2, I can get a straight print that I'm pretty happy with. But when I compare it to other working prints, I find I'm inconsistent with getting D-max. Sometimes it's there and sometimes it's not. I was curious whether 1) other people make their straight prints with D-max in mind, and 2a) if yes, what is their technique? 2b) If no, and they get D-max with burning in, then I'm happy with where I'm at.

Here is the video where I learned the technique I like: https://youtu.be/woXZb8gjG4o
I modify it by using test-strips instead of full sheets, and using f-stop timing, but other than that it's the same. The reason I like it is that for each test strip, you get to evaluate both highlight and shadow information, and the time between your "good" highlight and "good" shadow slices gives me an easily quantifiable method of determining how contrast should be adjusted.

@RobC: I am still definitely learning, but I would disagree with you that I am "chasing a magic bullet". I've spent quite some time to read the theory behind "basic" and split grade printing in Way Beyond Monochrome, so I'm not just trying something and giving up because I can't get results that I like. The reason I switch techniques is because I'm learning, and I want to see what benefits there are to other methods, which is why I decided to experiment with split grade printing. Through this experimentation, I learned that so far, I prefer my current method because it is the fastest and easiest (cognitively) to figure out my base print time. I can get to the same result using either split-grade or the "basic" technique that you're describing, but for speed and ease of use, I prefer the method I'm currently using. (When I say "basic", I don't mean it in a condescending way, just as a label for the method that's under the "Basic darkroom printing" section in Way Beyond Monochrome, which I've read very thoroughly. If there's another name for this method please let me know).

I'm using Ilford Multigrade filters which go above the condenser. In terms of determining true film speed, I'm printing "proper proofs" using the method on the halfhill.com website. I'm pretty close to my ideal with 2 cameras, but just tweaking both my development time (with HC-110), and which grade filter to print the contact sheets with in order to get a good representation of what a straight #2 print will give me. Because I have a condenser head, the contrast seems to increase when I go from a contact sheet to an enlargement. I wish I could print my contact sheets with a #2 1/4 grade, but I don't have a VC head and I'd prefer not to do split-grade just for contact sheets.

So hopefully that gives you an idea of where I'm at in my darkroom education. I'm obviously not an expert but I feel pretty confident I'm way past the "toe" of the learning curve.
 
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banandrew

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I've seen one of Bob Carnie's *stickied* posts and it was very enlightening to see into the mind of someone so experienced. I'll do a search for his posts and see what else comes up. Thanks for the recommendation.
 
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banandrew

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I've seen one of Bob Carnie's *stickied* posts and it was very enlightening to see into the mind of someone so experienced. I'll do a search for his posts and see what else comes up. Thanks for the recommendation.

Actually, reading that sticky post again had the information I was looking for, and as you said MattKing, he gets a single-grade base print and then does a "blast" with #5 for a % of the time.in order to get deep blacks. I guess if it's good enough for Mr. Carnie, it's good enough for me so I'll stick with my current method and not worry about getting D-max/min in the straight print, and then "blasting" in the blacks and dodging to keep whites where I want them.

Thanks everyone for the responses, there's so much great information in this community and I'm glad I came here to ask.
 
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