Arches Platine paper is sucking back sensitizer in Winter (lower humidity.)

[Zero_Equals_Infinity]

I am finding that as winter has set in and the RH in my darkroom has dropped that the amount of sensitizer that is required on my Arches Platine paper has gone up substantially. (And I actually rather like the more sepia tone for some prints.)

My question is: How do I go about reducing the amount of sensitizer that is necessary? I am using 2ml each of LiPd and FeO for a 100 sq inch print, and that is excessive.

I was thinking of either:
a) Pre-conditioning the paper with an ultrasonic humidifier in a small sealed environment-- humidifier, rack and plastic bag over the works;
b) Misting the paper with an atomizer before applying sensitizer;
c) Diluting the sensitizer by adding water before applying.

Typically in the summer months I was using about 1.5ml each of LiPd and FeO, which also seemed a bit on the high side, but not nearly as bad as 2.0.

FYI, I am using the Sterling Watercolour (synthetic sable) brush from Bostick and Sullivan Bostick-Sullivan :: Brushes & Coating Rods :: Synthetic Sable Brushes


Thanks in advance for your comments and ideas.

 

[Kerik]

Pre-humidify the paper. I like using a simple steam humidifier. Run it in the room to get the room humidity up, or the paper will just dry out again. 2 ml each is a LOT for 100 sq in. I use about 1 ml each for an 8x10.

 

[Zero_Equals_Infinity]

I agree 2ml is a lot. I use laboratory grade variable pippets for measurement into a shot glass and pour it onto the paper and spread as per usual. Perhaps there is something about this batch of paper, but it sucks back the sensitizer like a camel drinks water. According to Bostick and Sullivan these brushes use 20-30% less solution than Hake brushes, so I am really left scratching my head. I may go buy another sheet from a different lot to verify that it is not a problem specific to a particular run.

I will pre-humidify the darkroom as per your suggestion.

Thanks.

 

[JBrunner]

Its dry where I live. I run a humidifier in the darkroom, sometimes even, I sprinkle water on the floor, but not where I walk.

 

[jeffreyg]

Humidity is not an issue down here in sunny south Florida. I also use laboratory pipettes and slightly dilute the emulsion with distilled water but I use a puddle pusher and find that 1.5cc total of emulsion easily covers a 64sq.in. print.

HOME

 

[Zero_Equals_Infinity]

Humidity is not an issue down here in sunny south Florida. I also use laboratory pipettes and slightly dilute the emulsion with distilled water but I use a puddle pusher and find that 1.5cc total of emulsion easily covers a 64sq.in. print.

HOME

How much do you dilute with distilled water? 10%? And would necessitate going through the process of recalibrating the correction curve? (I suspect at least tweaking is required.)

Thank-you,

Nick.

 

[Loris Medici]

Wow, 2 - 2.5ml (depending on paper) *LiPd+AFO* per 100 sq in. is perfectly normal by my standards, perhaps it's different when using FO? (I use the same amount for Vandyke and Cyanotype too...) Jeffrey's 1.5ml per 64 sq. in. is pretty much in parallel with my figures too, but I use a brush not a glass rod.

 

[artonpaper]

Try coating the paper with glycerin prior to sensitizing. (This suggestion came from Ron Reeder.) I coat with glycerin the previous day or early on the day of printing so the paper has time to dry. Try about 10% glycerin with distilled water. I haven't used Arches in a long while, but in general when the central heating is on I run a simple cold water humidifier and I start coating when the humidity gets up to 40%. During that time I hang the sheets of paper in the room so that they absorb some humidity. This works for both traditional Pt/Pd and Ziatypes. Of late I've been using Revere paper with similar results and I haven't had to use more than my usual 30 drops of solution.

 

[Zero_Equals_Infinity]

Thanks Arton, I will give that a go. It just seems a bit silly to be needlessly using too much expensive sensitizer if no benefit accrues..

 

[pschwart]

Thanks Arton, I will give that a go. It just seems a bit silly to be needlessly using too much expensive sensitizer if no benefit accrues..

You can also try adding a drop or two of polyvinyl alcohol to the drop count. No prep or precoat required.

 

[artonpaper]

I would just like to add, I am of the opinion that Arches Platine is problematic. When I first went to purchase some, years ago, the people at New York Central, who really know paper, told me that it varied greatly from batch to batch and serious users of that paper kept track of batch numbers, etc. The first prints I made were all mottled looking. I got all kinds of advice from different people. I found that very hot developer, a suggestion of one of my students who worked with renowned printer Arkady Lvov, and a five minute developing time time, my own accidental discovery, gave me good prints. At the time my favorite paper was Crane's Cover, and I didn't think the Arches was significantly better, image wise, although it was sturdier. When Crane's took a nose dive and no longer worked, I switched to COT 320. COT seems consistant and trouble free. I like the surface of Arches a bit better, but it's not worth the trouble. I've been using Revere paper of late and very much like the feel and the surface of the paper. It does not scan well, if that matters, but it is quite rich and so far consistent. I use one coat, no pretreatment, and it works for both conventional develop out Pt/Pd, and Ziatypes. I have also experimented with Buxton and Herschel, both good strong papers with good image quality, but the surface is too rough for my taste. I really miss Crane's Cover, and once great Crane's Platinotype.

 

[pschwart]

I have heard the reports about problems with Platine, but I have used it for many years, purchased from various vendors, and never gotten a bad sheet. Same goes for COT320, though availability has been a problem, so these are my standard papers. I haven't tested the reformulated Revere yet.

 

[Kerik]

My experience with Platine is more like Arton's. Inconsistent. Excellent when its good, pain in the ass when it's not. Also agree that COT is a very consistent paper and is worth the extra $$ most of the time.

 

[Zero_Equals_Infinity]

I am getting the mottled look and especially where there is little tonal variation in a part of the image. It most often expresses in the upper-mid tones towards white (Zone VII +). I was suspicious that it may have to do with the negative, (which looks "grainy" in the same part of the tonal range.) I am using MK to get enough blocking to reach dMax in the negative on an Epson R3880 printer. I have been contemplating changing to the Jon Cone inkset to see if that addresses the problem.

 

[Kerik]

Using MK ink tends to make negatives that print grainy in pt/pd. Not recommended for digital negs, IMO. I use a 3880 now and a 3800 before that. You can get the density you need without MK ink. PK is the way.

 

[Zero_Equals_Infinity]

I was unable to get Dmax (pure white on print) using PK, which was why I jumped to MK. (I am using Lithium Chloropalladite, Ferric Oxalate, and NA2 - 2.5% at a ratio of 20:20:1, and Potassium Oxalate developer (2 min), Water bath with citric acid, EDTA and Sodium Sulfite baths (1 & 2), followed by rinse.)

I have been contemplating jumping to the Jon Cone inkset for digital negatives -- see Digital Negative Update | PiezoPress It is a pricey initial expense, and if it solves my problem and yields low-grain smooth tonal transitions I will be a very happy camper.

 

[pschwart]

I also find MK to yield grainier negatives than PK, so I don't use it for carbon transfers. PK is a poor UV blocker on the 38xx, but I can get extremely smooth tones in palladium using MK and colorized negatives; the prints are visually identical to prints made from negatives printed with Piezography ink on an Epson 1400. If you are using colorized negatives you may need to find a different color as this can affect graininess. If you are using a QTR profile you may have to do considerable tweaking.

I was unable to get Dmax (pure white on print) using PK, which was why I jumped to MK. (I am using Lithium Chloropalladite, Ferric Oxalate, and NA2 - 2.5% at a ratio of 20:20:1, and Potassium Oxalate developer (2 min), Water bath with citric acid, EDTA and Sodium Sulfite baths (1 & 2), followed by rinse.)

I have been contemplating jumping to the Jon Cone inkset for digital negatives -- see Digital Negative Update | PiezoPress It is a pricey initial expense, and if it solves my problem and yields low-grain smooth tonal transitions I will be a very happy camper.

 

[Zero_Equals_Infinity]

Hi Philip. I went down the MK road with QTR during the summer, and it was intensely frustrating. MK seemed to answer the problem ... except for that damned mottling.

So now I just want a good solution, and Jon Cone provides a set of correction curves for different density ranges that looks pretty promising. The distribution of inks looks well balanced in the curve set that he provides. If anyone here has experience using the inks and correction curves he has provided, please chime in.

 

[pschwart]

Right. That's why I said "If you are using a QTR profile you may have to do considerable tweaking." Colorized negatives on the 38xx using MK are quick and easy and provide very smooth tones using inks you already have. The mottling you saw might be caused by a QTR QTR profile that is laying down too much ink and the negatives are drying unevenly. This would be my guess since you reported the mottling in the upper midtones and highlights. If this is the problem it is easily remedied.
Piezography works fine in my 1400. It's true the Cone ink offers economy over Ultrachrome in the longer term, but: initial cost is high, there is no entry-level way to test drive the solution, you will essentially be dedicating the printer to monochrome, and the negatives are more fragile (easily abraded, ink rubs off on your finger) than those made with Ultrachrome. That doesn't make it a bad solution, just some things to consider.

Hi Philip. I went down the MK road with QTR during the summer, and it was intensely frustrating. MK seemed to answer the problem ... except for that damned mottling.

So now I just want a good solution, and Jon Cone provides a set of correction curves for different density ranges that looks pretty promising. The distribution of inks looks well balanced in the curve set that he provides. If anyone here has experience using the inks and correction curves he has provided, please chime in.

 

[Zero_Equals_Infinity]

Thanks for the information Phillip. Did you use the QTR curves that Jon provides or did you make your own? If you used his, which one did you use, and did you like the results? I am commiting the printer to making digital negs only, so the loss of flexibility is not an issue for me. The fragility of the neg is a bit disconcerting. Did you encounter any problems with ink adhering to the print from the negative while printing? Any other caveats?

 

[pschwart]

- The Epson 1400 is not supported for making Piezography negatives so I use my own profile. I have never
used Cone inks in my 3800. Maybe I will if I purchase a new 17" printer ...
- I always store and print my digital negatives in 2 mil polypropylene bags. High humidity might be a problem,
but my environment is about 50% and that has been fine. Even a soft brush will abrade the negative,
so don't touch and get it into a bag as soon as it is dry.

Thanks for the information Phillip. Did you use the QTR curves that Jon provides or did you make your own? If you used his, which one did you use, and did you like the results? I am commiting the printer to making digital negs only, so the loss of flexibility is not an issue for me. The fragility of the neg is a bit disconcerting. Did you encounter any problems with ink adhering to the print from the negative while printing? Any other caveats?

 

[artonpaper]

You may want to get some COT 320 fro your tests, and this way you are sure to rule out paper problems. I use an Epson 3800 with Mark Nelson's proprietary Precision Digital Negative system (PDN). It begins by testing for a color ink that gives good masking at a deep eposure. I must say that I have printed inkjet negatives from scans of 8 x 10 negatives (to correct for defects) and can see very, very little or no difference in print quality. His system is well thought out and logical. BTW, I use Photo Black, but just how much if any of it is contributing to my green negatives I can't say.

 

[Zero_Equals_Infinity]

Thanks for the idea Arton, I will see about sourcing another paper for purposes of testing. I do note that I can see "graininess" in the negative, and especially where Y and MK are laid down heavily. (Y and MK track closely in my correction curve until the last 10% of the curve when the MK curve starts bending to a steep slope.) The graininess starts manifesting around zone VII (70%) on uniform background such as sky.

I have included the curve for reference as an attachment.

My sense is that the graininess is related to MK and the curve becoming predominantly Y & MK alone from 80% on. My hope is that the Jon Cone inks and curves will put this to bed once and for all. (As Philip alludes, it is a bit of a leap of faith to change up the inkset, and an expensive one at that.)

 

[pschwart]

If you really want to change inks, go for it, but your QTR profile is the most likely source of your problems. Most are probably using native Ultrachrome in the 38xx and achieving good results with QTR or colorized negatives, so my suggestion would be to run a few more tests before switching. QTR is a tweakers delight, so I would take that out of the equation for now and try colorized negatives. You have everything you need so the cost is only a couple of hours of your time. PDN works well, but you can use RNP arrays to determine an appropriate color: Dead Link Removed.
If you still see mottling, then time to reexamine the platinum printing workflow.

 

[Davec101]

It is my understanding Cot 320 is essentially Arches Platine coated with a thin layer of gelatin and then marketed by Burgger. This was identified when on one pack of Cot 320 the Arches Platine watermark was still visable. I stocked up on the older version of Cot 320, latest batches I have purchased have not been as consistant as the old, i put this down to recent bad batches of Platine making its way through to the Bergger paper. Have moved over to other papers, best advice to keep trying new papers and when you find one you like stock up on as much as you can afford.