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  1. #11
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    Quote Originally Posted by Loris Medici View Post
    singerb,

    Try gold-thiourea toner if you can mix it yourself. It's very good in giving neutral - close to neutral results and it tones the highlights and the shadows at the same time and rate (non-proportional). It keeps very well too, unlike gold-thiocyanate toner. See this article for the formula. (At the bottom.)

    Hope this helps,
    Loris.
    I used to do a lot of kallitypes and I used the thiourea gold with great, neutralish results. Easy, fast, nice.

  2. #12

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    Quote Originally Posted by Loris Medici View Post
    singerb,

    1. What paper do you use? (Alkali buffered papers aren't good for the purpose; you need a neutral / neutralized or acidic paper...)
    2. Do you experience bleeding while washing / toning / fixing?
    3. Do you double or single coat? (I think you double coat, but asking to be sure...) If double coating, can you please describe your workflow?
    4.a. Are you sure that you use a negative with enough density range? (Vandyke requires very contrasty negatives, I'm talking from memory - therefore I'm not sure - but my negatives' DR was around log 2.8 or a little higher - for double coated paper...)
    4.b. Have you checked your exposure time with a 31 or 21 step tablet?
    1. Rives BFK, same as I've been using for cyanotype. I've read other people getting good results with it for Vandykes and similar.
    2. Describe bleeding? I don't think so.
    3. Double coat, but I may not be drying the first coat long enough first. Current workflow is coat all the pieces, then go around and coat again. I'm going to try a cool hairdryer before the second coat tonight.
    4a. No, I'm not sure the negative in the example is contrasty enough. However... ->
    4b. Yes, I have checked exposure times with a step wedge, and I do see what appears to be full "black" as well as whites, with a reasonable gradation; however...->

    I'll run another test tonight to make sure I'm fully exposing the prints, as well as check my double coating method. This thread: http://www.apug.org/forums/forum42/6...g-vandyke.html has an example of more of what I'm looking for too, so I'm ordering supplies for a small batch of gold-thiourea toner, and hopefully I'll be able to try that this weekend.

  3. #13

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    1. I don't know much about Rives BFK, but from what I read in various product descriptions on the net it's a buffered paper. Buffered papers aren't good for iron processes in general, maybe you can switch to a neutral / acidic non-buffered paper OR acidify your Rives BFK using 2%-5% solutions of acetic, hydrochloric or oxalic acids. (There are a couple of more options too...) Alkali paper will give you long printing times, low dmax and bad tonality.
    2. Bleeding: Silver migrating into the wash water in the first bath, sometimes staining adjacent whites. Bleeding is a sign of improper coating (too thick and/or bad absorption) and/or chemical incompatibility. It will ruin your image and decrease dmax.
    3. When double coating, I was waiting the paper loose its shine (= sensitizer fully absorbed / paper still very moist. About 3-5 minutes depending paper and environment.) then immediately do the second coat. Therefore, I don't think that you definitely need to wait the paper dry.
    4.b. Do you see merged steps in the step tablet print? You need steps at least two steps merged. With Vandyke and other print-out processes this is often tricky; those processes have very long / pronounced shoulders + if you overexpose then you get bronzing, which makes evaluation harder. I often highly overexpose then scan the print and measure to see which step gives me maximum black and lessen exposure according to that. (Example: 31-step tablet, 20 minutes exposure, dmax at step 5 -> 5 - 4 = 1, 4 steps (1 1/3 stops) for pulling dmax back to step 1, pull 1 step more for the base density of the step tablet (~ log 0.09 ~ 1/3 stop for UV light), then add base + fog density of your negatives for finding the actual exposure time. I use digital negatives, and the particular media I prefer cuts about 2/3 stop of UV light. Therefore the correct exposure time for my negatives should be 20:00 - 1 1/3 - 1/3 + 2/3 = 20:00 - 1 = 10:00.) BTW, please note that many prefer to use 90% dmax, in order to avoid the shoulder of the printing process. (This last point is more significant in the context of real in-camera negatives.)

  4. #14

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    1. From http://www.alternativephotography.co...survey-results I see one person successfully using it, and nobody saying it doesn't work. I do have some Cranes Kid Finish still, so I can run a comparison with that too. I do see other people printing Van Dyke on BFK, but no info about whether they're doing any acid coating. However, I also don't see anybody saying "this will not work".
    2. What would this look like vs just unexposed sensitizer (for example, the borders if you mask the negative) coming off?
    4b. From inspection, it appears there are merged steps in the print, but I can measure that for sure later from a scan. However, I'll bracket some step wedge exposures to make sure my times are good.

  5. #15

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    Hi again,

    1. As I already said I don't have experience with that paper (OTOH, if I'm not mistaking Rives BFK has many variants), therefore I will leave that to others that actually used that paper for Vandyke. In any case, as a rule of thumb, stay away from "buffered" papers... (I mean in the context of iron / iron-silver processes.)
    2. It will look like stain + halos around dark + dark glowing. And you definitely see silver coming out from darks in the water bath...

    Good luck!

    P.S. How your paper behaves with Cyanotype? Do you have any samples to show? It may help in eliminating the paper as the cause of your problem...
    Last edited by Loris Medici; 04-27-2010 at 03:05 PM. Click to view previous post history. Reason: Added P.S.

  6. #16

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    Real inspection will have to wait for the prints to dry, but I can say now that Cranes Kid Finish doesn't appear to act any differently to the Rives except in terms of paper weight and thus handling the quantities of solution and soaking. It also doesn't appear that I have bleeding.

    I do have a question or two about double coating: in prints with sloppy borders I can fairly easily see where the double coat doesn't quite cover the single coat. Do you just get better at this with practice? I could also mask the negative during exposure, but for some subjects I like a small border. I should mention that I'm brush coating, not rod coating.

    Also, could differences in toning be related to areas of single coating vs double coating?

  7. #17

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    Quote Originally Posted by singerb View Post
    ...
    It also doesn't appear that I have bleeding.
    ...
    That's good. Actually I wasn't expecting that you experience bleeding since to my knowing Rives is a pretty absorbent paper; It's designed for etchings and such, therefore it has a relatively weaker sizing - I mean when compared to hard papers like Fabriano Artistico and Bergger COT 320. Asked anyway to eliminate one probable cause of your problem...

    Quote Originally Posted by singerb View Post
    I do have a question or two about double coating: in prints with sloppy borders I can fairly easily see where the double coat doesn't quite cover the single coat. Do you just get better at this with practice? I could also mask the negative during exposure, but for some subjects I like a small border. I should mention that I'm brush coating, not rod coating.
    That's pretty normal / natural and shouldn't pose a problem as long as it's limited to borders / doesn't affect the image area...

    Quote Originally Posted by singerb View Post
    Also, could differences in toning be related to areas of single coating vs double coating?
    Double coated will tone as successfully as single coated. (And vice versa.) Of course, results will be different due to the difference in the strengths of the coatings.

    Your sample image was definitely weak (both at the black borders and inside the image area). Make sure you have a negative with enough DR + definitely try gold-thiorea. If you still have the same problem with other papers (and gold-thiourea toner) then it's either the negative or the sensitizer. (I can't think of any other reason! BTW, I'd rather start from the negative...)

    BTW, you didn't tell much about your workflow; what fixer and fixer strength do you use? Do you tone before fixing or after fixing? (It's better to tone before fixing, to reduce the possibility of bleaching in the fixer. I use 2% plain anhydrous sodium thiosulfate and fix for 2 minutes...) I mean; can you get good results with non-toned prints, primarily?

    Regards,
    Loris.

  8. #18

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    Ok, looking at the dried prints this morning, I can say that perhaps I was underexposing a little, as the step wedge I did last night appears to have deeper "blacks". I'll have to verify that with a scan. I also printed a more contrasty negative, and it certainly looks like I'm getting good shadow values. I'll post up a scan tonight. I toned the print(s) and it's still got that grey/brown split look.

    I'm toning pre-fixing, using a relatively weak (I think - with no scale yet it's hard to be sure) sodium thiosulfate solution. I'm not seeing bleaching in the fixer for un-toned prints, just the color change. I do seem to be able to get good results with untoned prints (mostly step wedges so far). Gold thiourea materials should arrive later this week, so I'm not going to do further tests until then.

  9. #19

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    As promised, a scan of the print with good DR, but still a grey/brown tone. Still, it's not bad, but I'm interested to see how the gold-thiourea does. I also verified from the newer step wedge that I had underexposed before, so I wasn't getting full shadow values.
    Attached Thumbnails Attached Thumbnails Scan-100428-0001.jpg  

  10. #20

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    I don't know if it's from the scan but it seems like you still have some potential for a better dmax. This looks like my prints with single layer, double layer were way better. (Again, could be the scan or maybe it's due the difference between or chemicals and/or papers...) I'm sure you'll get a much better result with gold-thiourea. Good luck again!

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