I’m consistently getting a DMax of L*26 with a MaldeWare Printing out process, using fresh chemistry. How does the PPE tool use my black point when considering a new curve during linearization? Does the linearization maths take my measured Dmin and Dmax and try to linearize the middle values? Or is there a lower density target black point that the new curve is trying to get me to hit (even though I have reached my Dmax given my workflow and cannot get darker blacks). Just trying to understand how I should interpret the new curves when I linearize. Any insight would help me a lot. Thanks.
Clear film produces dMax, but dMax is a product of hydration and exposure which is conducted well in front of linearizing the process.
What is your standard hydration that you are using as per:
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rH% and temp?
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how long is the paper hydrating in this prior to coating with the sensitizer?
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which sensitizer (meth 1 or meth 3)?
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how long is the paper hydrating post coating with the sensitizer prior to exposing?
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did you determine dMax based on step exposures through a strip of unprinted Pictorico Ultra OHP film?
This would be your first step prior to your first exposed linearization target. hydration and exposure. dMax will follow the linearization process as long as you have standardized your hydration (pre-coat, post-coat) keeping rH/temp and times exactly the same. it is that sensitive to exposure and contrast.
Jon
Hi Jon,
Paper is kept in a hydration tent at 70f and 70%RH for 2 hours before coating, then after coating it rests in ambient room temp for 5 mins before going back into the tent for 90 mins to settle before exposure. I use Fe1 (made up only a week ago) and 50:50 PtPd. The min base exposure was determined by exposing a test strip over the UHP film and stopping at the point the Dmax over the UHP was not getting any darker. I hav ebeen printing this for a few years and never really had a higher Dmax than 1.28. I just want to check that the linearisation is not trying to increase my dMax but simply linearising the values between my black and white. Thanks
Linearization does not increase dMax and generally will not decrease it.
Here is something to consider. Methodology 1 does not produce as much dMax as Meth 3 can, and your 70% is very high lending towards a cool version of the normally warm Methodology 1. Perhaps you might consider instead using Methodology 3 at about 55% rH which is slightly warmer than the neutral of Methodology 3. It would also produce higher dMax. Their sensitivity to UV is quite different and you would want to start at finding the base exposure again that produces the highest dMax.
Jon
Thanks Jon,
I might try the Fe3. That might be the best way to go really.
I like cooler plumb colors rather than the sepia colors, which is why I go for the higher humidity levels. Fe3 might be a good option to try.
The only issue is that in London it might be hard to get the humidity DOWN to 55%.
I have also been having a second problem: large patchy areas on the print. The lighter patches are warmer sepia and the darker patches are cooler. These are very blotchy and quite big. My guess is that there is some unevenness in the moisture content on the paper. As this is a new problem, I have been looking at any new variables and the only one I find is that my negative size is bigger now than the size of the 11x15 paper. (I’m in London so the Pictorico sizes are different here). The overlapping UHP may be causing some snorkelling of the air in the few seconds it takes before the vacuum on the Verified UV exposure unit lifts the the neoprene blanket. There is a lot of air running through the system for those seconds, possibly under the neg drying out sections of the paper.
I have already ruled out degraded sizing of old paper (by getting new Revere paper stock), degraded Fe solution (made new solution last week), too much glycerin (I reduced the solution from 15% to 5% VV).
This “mapping” effect is new and consistent in that it has been on every single print that I have made in this series, about 15 in total. It seems to be much better when I trim the neg to the paper size, but it is not completely gone away on all prints.
Have you heard of this issue?
Could the lower humidity Fe 3 help me?
Is there a way to improve the gasket in the vacuum frame which seems to have lost a bit of its seal.
I prefer Methodology #3 at 63-65% rH @ 70-72ƒ - just slightly eggplant purply off neutral. Lovely!
The blotchiness may be from high humidity and I find it helps rather than to hang the paper after coating to rather allow it to lay flat on glass while hydrating. I keep my post coating hydration to 60 minutes sharp!
With Revere I use both Tween 20 (or Polysorbate 20) and glycerine…. I do not have my volume % of that on hand. I think it may be 5% each by volume. But the blotchiness was solved by hydrating on glass. The gasket can be removed and replaced but if you press down does it seal? You can not let the pictorico film slide touch the seal at all…
J
Hi! Fe Methods 2 or 3 (referring to my book, Platinotype) will give you cooler tones than Fe1. Higher hydrations (anything above 70%) will begin to slightly reduce Dmax compared to prints hydrated in the 50–70% range — much of this is discussed and illustrated in the book. You may want to reduce hydration slightly, say to 65% at 70°F.
The 90-minute post-coat hydration is good, but you may not need to wait 5 minutes between coating and hydrating — you can go straight from the completed coating to hydrating the print. The only reason to pause is when working with a heavily sized paper, where the sensitizer needs time to absorb to the point where just a light sheen remains on the surface. Waiting between coating and hydrating can sometimes introduce inconsistencies if the atmosphere in the coating area is fluctuating (though it sounds like you have everything well under control).
Regarding the blotching — increase your pre-coat hydration from 2 hours to between 12–24 hours.
Thanks!
Pradip