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  1. #21
    JBrunner's Avatar
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    You don't say what kind of head you are using, but if you are using a VC or color head some of the info in this thread may be useful.

    http://www.apug.org/forums/forum41/3...-vc-heads.html

  2. #22

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    I have to chime in here as well:

    First, whether you can increase contrast by "tweaking" the development depends on a couple of things. 1) The paper: some papers just do not react well to developer manipulations. 2) The developer you use as "standard." Dektol 1:2 is fairly contrasty already. You can try full strength, adding carbonate/Kbr, increasing dev time etc. and see if it works, but unless you are developing for less than 2 1/2 minutes in the Dektol, you may not see much change. (Getting less contrast would be a lot easier...)

    Second, much of what is perceived as increased contrast when "tweaking" developer is really a change in characteristic curve shape that gives more contrast to a local area, but not a real change in overall contrast. This, I believe, is the advantage to playing around with your developers. However, it is possible to come up with a steeper overall curve, which is increased contrast as far as papers are concerned. (As opposed to films, which are rarely developed to d-max, the d-max and highlight density of papers stay relatively constant. It is the curve shape that determines the range of negative densities that can be printed on a given paper and thus the "contrast" of the paper.)

    Three, selenium toning the negative will give the negative a real contrast increase. However, if you developed the negative in a staining developer (e.g. PMK), the toning solution will remove the stain, effectively negating the contrast increase. You may be able to recover the stain by bathing the neg in spent developer or an alkaline solution after the toning, but I am not sure, as I haven't tried it myself.

    Selenium toning your print will increase d-max and contrast overall. However, the highlights are least affected. Sometimes, printing a bit lighter and selenium toning is just the ticket, however, bringing more life to the highlights than one might expect.

    My recommendations: First, old paper loses contrast. Try a fresh batch of paper if yours has been around for a while. I have some old Seagull grade 3 that is down to about grade 2 now.... Try toning if you aren't already.
    If you really need an overall contrast increase, try selenium intensification of the neg (as long as it wasn't developed in a staining developer). It really works and can be done locally as well. Selenium toner 1:2 for 5 minutes is toning to completion and approx. a one-grade increase (maybe a bit less). Less time will give you less contrast change. This is a proportional increase and usually very gratifying when it works. These are the "easy fixes" and will give your prints more snap.

    If you want to play with the developer, try:

    1) Full strength Dektol with an extended development time (5 minutes is a good starting point) and reduced exposure to compensate. This can give a darker, heavier print. If you want more highlight contrast, but the blacks are fine, use the standard dilution and...

    2) add carbonate and/or KBr (or benzatriazole) to your developer. Adding carbonate alone increases developer activity and is somewhat like inreasing developer strength. It affects the blacks mostly. KBr restrains development in the the highlights and can, with increased development/exposure time, give a print with more highlight separation. You can use both together to balance each other somewhat and get some darker blacks and more highlight separation at the same time. I keep pre-mixed solutions of carbonate and KBr on a shelf above the developer for easy "tweaking." I usually just pour some in, but you can measure if you like. There is a good discussion of using carbonate and KBr in the Darkroom Cookbook. You will have to adjust exposure and/or development time when "tweaking." Again, some papers react better to these techniques than others.


    You can bleach up the highlights by immersing the entire print in a potassium ferricyanide solution. You can also selectively bleach certain areas of the print. Bleaching techniques are a bit complicated to go into here, but there is lots of info on the web. If you haven't bleached before, take time to master the techniques as they can be tricky.

    Bleaching affects the way the print will tone later, so if you tone, especially with selenium, be aware that split toning can result. When I bleach locally, I use a very dilute toning solution and watch very carefully so I can pull the print before split toning occurs. I usually end up wasting the first one...

    If none of the above options works, you need to find a contrastier paper. Maybe you will have to resort to VC or a different brand of graded that still comes in grade 4 (Seagull, Kentmere, ???). As a last resort, there are intensifiers for the neg. So far, I have managed to get by without having to resort to more intensification than selenium offers, so I can't offer first-hand assistance with that.

    Hope this helps,

    Doremus Scudder

    www.DoremusScudder.com
    Last edited by Doremus Scudder; 05-21-2007 at 03:53 AM. Click to view previous post history.

  3. #23
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    increasing contrast on graded paper

    Another answer is Dr. Beers developer - I use it almost exclusively. It's a part a and part b solution. different dilutions give you approx 1/4 grade change in both directions. There are 7 different dilutions so you can go up or down as much as 3/4 grade.
    Tim

  4. #24

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    I wouldn't do anything to the negative, since there's nothing wrong with negative per se, any posttreatment is risky, and you might want to print it on a different paper later.

    I do endorse using bleach on the print. You can use Farmer's, or for more control, pure ferricyanide followed by a separate fixer bath. That's a slower method and more controllable. If you overdo it, you can redevelop the image in a developer bath (before fixing, of course). I've use this method on Panalure, the only fixed-grad non-lith paper I've used in recent years.

  5. #25
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    Quote Originally Posted by Richard Jepsen View Post
    I have no experience working with graded paper and need advice on raising print contrast. ...
    Maybe try Tetenal Dokumol liquid? It is a contrast increasing developer.
    If you're not taking your camera...there's no reason to travel. --APUG member bgilwee

  6. #26
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    I was thinking of Glycin developers. I have used Ansco 130 a lot with VC papers, and way back when I used the VersaPrint II for neutral to cold tones. It appeared that letting the print sit in the developer for longer than the 'full development/contrast' time, the print would continue building blacks. Exactly how much I'm not aware, but there was a definite change (I don't measure with a densitometer, I just don't like to get too scientific), perhaps as much as 1/2 stop. Whether that works on graded papers or not, I have no proof, but see no reason why it wouldn't.
    - Thomas

  7. #27

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    1/2 grade

    Edwal Ultra Black will give you a 1/2 grade increase. I regularly print on number #3 paper with 120 size acros and do it with rotary development and amidol and a water bath. not exactly the hardest thing in the world. some films like Tmax400 or Pl100 do contrast increase better than others but I don't see why most films like trix (and I've done it there too) won't develop to a grade 3 or higher contrast. keep it simple folks. I only do selenium toning if I really screwed up. better to develop to the right contrast from the beginning....
    Best, Peter

  8. #28

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    Oh why didn't I think of this... change the head :-)

    I mean, change the head from diffusion to condenser, and to a well adjusted condenser, and to a point source...

    I use Durst Laborator 138 as my main enlarger, and when the condensers are matched to the lens, I get a bit (about a full grade) of increase in contrast from condenser head. I also have a point source unit and this gives me quite a bit of contrast increase, although, this comes with the cost of very sharp and distracting grains and dusts on the negative.

  9. #29

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    Quote Originally Posted by climbabout View Post
    Another answer is Dr. Beers developer - I use it almost exclusively.
    It's a part a and part b solution. Different dilutions give you approx
    1/4 grade change in both directions. There are 7 different dilutions
    so you can go up or down as much as 3/4 grade. Tim
    I'll likely have a small batch of Beer's A mixed up tonight. From
    blend 1, which is just the metol portion at a correct dilution, to
    blend 7, there is a very easily seen increase in contrast. In use
    Beer's A is the same developer as Ansco 120. Beer's B is the
    hydroquinone portion. The combination, A&B, has a parallel;
    A. Adams A&B Ansco 130.

    If new to Home Brew, Beer's A&B is a good place to start.
    A contrast control developer with only five ingredients. Dan

  10. #30

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    I doubt whether the Beer's no. 7 will be any more contrasty than Dektol straight. The Edwal ultra black might be, I'm not sure since I haven't used it in a long time.

    Changing to a more collimated light source will increase contrast a bit. I didn't think of it immediately.

    I agree about post-processing negatives except in the case of selenium toning. Selenium intensification of the negative is easy, safe, and actually protects the negative somewhat (in the same way selenium toning protects prints). The only effect is the increase in contrast. It is, however, not reversible, so one should be sure they can deal with the increase in contrast before proceeding.

    I haven't tried the "blue-light-printing" with graded paper (this seems more like a technique for VC papers...). If there are silver halides of varying sensitivity/contrast in the graded paper emulsion it might work... Another experiment for me for later.

    Boy, I sure miss Oriental/Brilliant/etc. grades 4 and 5!!

    Doremus Scudder

    www.DoremusScudder.com

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