Flocculation and Gum prints

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Davec101

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I have been testing gum over cyanotype am just have problems with the final magenta layer. I think this is flocculation, can anyone confirm this. Below is 100% crop, it almost looks like grain. Cyanotype goes on fine as well as yellow (Transparent Yellow, Windsor Newton) Paper is Fabriano Artistico Bright white (300lb). I just got away with it on the bottom print, but its still present and also needs less yellow.

Anyone know how to resolve this, thanks.

5019596995_d7d1fdda48_z.jpg


5019584651_a27abafe1b.jpg


5019606369_c609085eb4_o.jpg
 

Loris Medici

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What pigment is that? I often see this with PV 19 (quinacridone rose). Try to use it as the second layer (not third) and brush / smooth well... Also, use very little; it's a very strong colorant.

N.B. All above for PV19R...

Regards,
Loris.

P.S. Nice results, nevertheless...
 

R Shaffer

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If it is an consolation, I find magenta to be a difficult pigment and I frequently get a similar grainy appearance. It is like tiny clumps of solid pigment get trapped in the paper fiber.

In my own anecdotal experience I have blamed it on poor/damaged sizing as I see it more frequently in areas that I have brushed heavily on prior layers. I used to see it more frequently, but I think as I have gotten better at sizing it has been less of a problem.

You could try reducing the pigment or sizing before magenta layer.

Hopefully someone with more gum experience will chime in and either confirm or rebuff my assumptions.
 

R Shaffer

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What pigment is that? I often see this with PV 19 (quinacridone rose). Try to use it as the second layer (not third) and brush / smooth well... Also, use very little; it's a very strong colorant.

N.B. All above for PV19R...

Regards,
Loris.

P.S. Nice results, nevertheless...

And I meant to also say these look great.

I use Winsor & Newton Permanent Alizarin Chrimson
 

Colin Graham

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I always had better luck blending PV19beta (quinacridone violet) and PR209 (quinacridone red). But I agree the effect works well in these.
 
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Davec101

Davec101

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What pigment is that? I often see this with PV 19 (quinacridone rose). Try to use it as the second layer (not third) and brush / smooth well... Also, use very little; it's a very strong colorant.

N.B. All above for PV19R...

Regards,
Loris.

P.S. Nice results, nevertheless...

Thanks Loris for the adivice, your spot on it is quinacridone rose. I get this effect even when trying it fresh on the fabriano with no other layers so there is something going wrong. I will try it as a second layer tommorow to see if it makes a difference. What are you using for magenta?
 
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Davec101

Davec101

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If it is an consolation, I find magenta to be a difficult pigment and I frequently get a similar grainy appearance. It is like tiny clumps of solid pigment get trapped in the paper fiber.

In my own anecdotal experience I have blamed it on poor/damaged sizing as I see it more frequently in areas that I have brushed heavily on prior layers. I used to see it more frequently, but I think as I have gotten better at sizing it has been less of a problem.

You could try reducing the pigment or sizing before magenta layer.

Hopefully someone with more gum experience will chime in and either confirm or rebuff my assumptions.

Hi Rob

I am going to try using less pigment to see what the result is thanks, the paper is bonded to aluminum prior to coating and as such I am neither shrinking the paper or sizing it as the paper remains the same size through out the whole process.
 

Loris Medici

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Hi Dave,

I use that pigment exactly (Schmincke), I found that the earlier I use it and the more vigorously I smoth the coating, I get less (or none) of this phenomenon. But mind that I don't ust the same paper (surface actually, I print on Artistico HP) and I size with either 3% (formalin hardened) gelatin or diluted PVAc glue (not Gamblin PVA Size!), therefore my observations may not apply to you...

Regards,
Loris.

P.S. I like that pigment much BTW; it's very strong and transparent - also very lightfast...

P.S.2. When I say second layer, I mean the first gum layer over the cyanotype / palladium...


Thanks Loris for the adivice, your spot on it is quinacridone rose. I get this effect even when trying it fresh on the fabriano with no other layers so there is something going wrong. I will try it as a second layer tommorow to see if it makes a difference. What are you using for magenta?
 
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Loris Medici

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It now occured to me that a little 70% isopropanol or few drops of Ilfotol / Photo-Flo may facilitate to get a more even appearance!? Maybe...

My observation was that pigment particles liked to get together, I mean - almost like particles were attracted to each other...

Regards,
Loris.
 

Colin Graham

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Great advice Loris, thanks. I tried PV19 rose again and used much less pigment and also added some water to extend the open time to brush and got much cleaner results. Moving the magenta layer up to right after the cyanotype layer seems to help as well. Or at least, you are spared the extra effort on a lost cause if the coating gets bungled!
 
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Davec101

Davec101

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Glad if that was helpful indeed...

Regards,
Loris.

I was just waiting for the dry down results before thanking you Loris,. Your help has been invaluable :smile:

Using less PV19 has helped the grain/flocculation as has moving it to a second coat after the Cyanotype. however I am not getting the red’s I really want .The scan below had two layers of magenta in succession. Am pleased with the initial results as it has its own type of quality compared to the Polaroid original, which is shown below the scan, however it has lost some of the coldness of the original. Any ideas of have to push those red values up to the original other than hand painting without effecting the whole image hue? I have tried a number of other red’s including bright red by Sennelier but they all seem to grain up on Fabriano.

5027206197_88de88cb5a_o.jpg


5027834730_3a68f5500f_o.jpg



5027253201_e2e040fba5.jpg


Here is another I am working on at the moment, needs quite a bit of work; has had two layers of magenta, needs one really, again some of those lights at the back should be red.

5027227629_69be9ea683_o.jpg

Just out of interest what side of the paper are you guys using, the watermark or the mesh side? I prefer the mesh as it easier to get masking tape of it when creating a border however the watermark/rough side has a great finish to it.
 
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Colin Graham

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What sort of separations are you using? For the life of me I can't get isolated, stand-out colors using RGB separations, and have much better luck with CMYK.
 

donbga

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What sort of separations are you using? For the life of me I can't get isolated, stand-out colors using RGB separations, and have much better luck with CMYK.

I primarily use CMY seperations made from the channels pallet. Creating CMYK produces completely different negatives.

DaveC I get intense reds when I need them doing bi-color gum over cyanotype.

I use Quinacridone Rose as the last layer. The M. Graham and Daniel Smith brands of this pigment work very well. 1 coat for the yellow and 1 coat for the magenta layer. You are going to hate me for saying this but you need to size your paper. I use a very thin watery layer for the magenta coat. You do not need to put alcohol into the pigment mix. Though I do use grain alcohol with my gelatin size to kill the sparkles.

I use FAEW and Rives BFK papers. With FAEW I print on the mesh side, though after double shrinking and sizing with 3% gelatin and hardening with 2.5% glut the surface is soft and smooth as a babies butt. I really prefer BFK.

And I also use a dremel tool to mix my pigment mixtures and my coating mixtures which uses saturated AD. I brush on the mixed coatings with a very slighly dampened very high quality hake brush followed by a even and light roll out with a micro-foam roller. Almost all magenta pigs cause oily mixtures which are plaqued with fish eyes. I do the final smoothing with a large badger hair brush once the surface gets just slightly dry to rid the coating of those. The badger hair brush works the magic.

I forget how you are creating your negatives but I use PDN and create an individual adjustment curve for each pigment, including the cyanotype layer. By doing this and using CMY negs. the color is placed very precisely in the print. An alternative which I will explore soon is to also use an ICC profile when working with the positive image before color seperation. This will aid in softproofing if you understand how to do that properly.

I develop my prints for 1 hour @ 70F. Often I will have to use a water atomizer to get the final layer of magenta to release. This provises a very fine mist of water to develop the pigment and help it release. If I find the magenta (or yellow not releasing) I'll develop in warmer water for a short period to get the development started. Of course brush development is needed in some areas just to clean out whites or intensify certain colors, but that's an advanced technique that requires finesse and practice.

Be gentle handling the prints while they face down. If you let them plop strongly in the water the magenta layer may just slough off from the shock wave created to the impact. A wave front reflects off the bottom of the tray and scrubs the surface of the print.

If you are familiar with the Adobe Ole Moire file, print that in gum until you have a perfect tri-color print as you can make it. It will teach you a lot.

Using cyanotype as the Prussian Blue layer reduces the color gamut and you find certain colors impossible to match or create in the green, blue, aqua hues if that is your goal. Using the Adobe file mentioned above will help you key in on reproduction of flesh tones.

I don't know about flocculation but I just call it staining which is what you've got.

Good luck,

Don Bryant
 
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Colin Graham

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I primarily use CMY seperations made from the channels pallet. Creating CMYK produces completely different negatives.


Don Bryant

Multichannel CMY/ RGB separations appear to be identical on CS4, regardless of conversion/inversion order. I wonder what I missing, because I can't seem to get the purer color separations in the negatives with that method. Yes, CMYK does give completely different negatives- that's why I suggested it. I get better results taking the black-building density out of the colors and just adding them back to the stronger shadows as needed. Anyway, for selective color images like this it might be worth a try, if he hasn't already. (BTW, the image should be converted to cmyk before inversion to keep the K info in the shadows and not muddy the highlights with it.)
 
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donbga

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Multichannel CMY/ RGB separations appear to be identical on CS4, regardless of conversion/inversion order. Am I missing something? Yes, CMYK does give completely different negatives- that's why I suggested it. I just like taking the black-building density out of the colors and just adding them back to the stronger shadows as needed. For selective color images like this it might be worth a try. (BTW, the image should be converted to cmyk before inversion to keep the K info in the shadows and not muddy the highlights with it.)

There is nothing wrong with using CMYK negs. Having the K channel gives you some other options though I don't recommend printing it with a black water color for anyone just reading along.

Using a CMY seperation can be just as effective though. We can still achieve black shadows if that is your goal. And use 25% less transparency material.

Don
 
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Davec101

Davec101

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I primarily use CMY seperations made from the channels pallet. Creating CMYK produces completely different negatives.

DaveC I get intense reds when I need them doing bi-color gum over cyanotype.

I use Quinacridone Rose as the last layer. The M. Graham and Daniel Smith brands of this pigment work very well. 1 coat for the yellow and 1 coat for the magenta layer. You are going to hate me for saying this but you need to size your paper. I use a very thin watery layer for the magenta coat. You do not need to put alcohol into the pigment mix. Though I do use grain alcohol with my gelatin size to kill the sparkles.

I use FAEW and Rives BFK papers. With FAEW I print on the mesh side, though after double shrinking and sizing with 3% gelatin and hardening with 2.5% glut the surface is soft and smooth as a babies butt. I really prefer BFK.

And I also use a dremel tool to mix my pigment mixtures and my coating mixtures which uses saturated AD. I brush on the mixed coatings with a very slighly dampened very high quality hake brush followed by a even and light roll out with a micro-foam roller. Almost all magenta pigs cause oily mixtures which are plaqued with fish eyes. I do the final smoothing with a large badger hair brush once the surface gets just slightly dry to rid the coating of those. The badger hair brush works the magic.

I forget how you are creating your negatives but I use PDN and create an individual adjustment curve for each pigment, including the cyanotype layer. By doing this and using CMY negs. the color is placed very precisely in the print. An alternative which I will explore soon is to also use an ICC profile when working with the positive image before color seperation. This will aid in softproofing if you understand how to do that properly.

I develop my prints for 1 hour @ 70F. Often I will have to use a water atomizer to get the final layer of magenta to release. This provises a very fine mist of water to develop the pigment and help it release. If I find the magenta (or yellow not releasing) I'll develop in warmer water for a short period to get the development started. Of course brush development is needed in some areas just to clean out whites or intensify certain colors, but that's an advanced technique that requires finesse and practice.

Be gentle handling the prints while they face down. If you let them plop strongly in the water the magenta layer may just slough off from the shock wave created to the impact. A wave front reflects off the bottom of the tray and scrubs the surface of the print.

If you are familiar with the Adobe Ole Moire file, print that in gum until you have a perfect tri-color print as you can make it. It will teach you a lot.

Using cyanotype as the Prussian Blue layer reduces the color gamut and you find certain colors impossible to match or create in the green, blue, aqua hues if that is your goal. Using the Adobe file mentioned above will help you key in on reproduction of flesh tones.

I don't know about flocculation but I just call it staining which is what you've got.

Good luck,

Don Bryant

Hi Don

Thank you very much for such an informative reply, quite a few things to digest and i hope you dont mind if i get back to you on a few of them, in relation to sizing the paper. Why is it important that i do this if my paper is not moving on the aluminium?

At the moment i am using FA traditional white as opposed to Bright White, do you know if there is any significant differences between the two other one being whiter than the other?

To create negatives I am using the curves i created for cyanotype for each layer as from what i read they are not to dissimilar from the way gum works, I maybe completely off on this one! I am inverting the RGB image to create CMY separations. Out of interest what is wrong with just using the RGB channels instead?

I will definitely start printing out the ole moire file and see where i am going wrong. Like you say i think using the cyanotype process will limit me however i am having fisheye/staining problems also with this layer using D.Smiths Pthalo Blue too so i reverted to the cyanotype process. In a way the gum prints dont have to be exactly spot onto the Polaroids but close. I think gum prints have their own quality which one should take advantage of rather than replicating another process, if you get what i mean.

thanks again.

P.S It might be better if you could change the topic title to 'Fisheye/Staining and Gum prints' as opposed to 'Flocculation'
 

donbga

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Hi Don

Thank you very much for such an informative reply, quite a few things to digest and i hope you dont mind if i get back to you on a few of them, in relation to sizing the paper. Why is it important that i do this if my paper is not moving on the aluminium?

At the moment i am using FA traditional white as opposed to Bright White, do you know if there is any significant differences between the two other one being whiter than the other?

To create negatives I am using the curves i created for cyanotype for each layer as from what i read they are not to dissimilar from the way gum works, I maybe completely off on this one! I am inverting the RGB image to create CMY separations. Out of interest what is wrong with just using the RGB channels instead?

I will definitely start printing out the ole moire file and see where i am going wrong. Like you say i think using the cyanotype process will limit me however i am having fisheye/staining problems also with this layer using D.Smiths Pthalo Blue too so i reverted to the cyanotype process. In a way the gum prints dont have to be exactly spot onto the Polaroids but close. I think gum prints have their own quality which one should take advantage of rather than replicating another process, if you get what i mean.

thanks again.

P.S It might be better if you could change the topic title to 'Fisheye/Staining and Gum prints' as opposed to 'Flocculation'

Dave I'm on my way out the door so I can't reply for a while. Probably not till tomorrow.

Don
 

R Shaffer

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Hi Don

Thank you very much for such an informative reply, quite a few things to digest and i hope you dont mind if i get back to you on a few of them, in relation to sizing the paper. Why is it important that i do this if my paper is not moving on the aluminium?

Dave,

Sizing the paper with gelatin fills in between the paper fibers so that the paper is less absorbent. The emulsion can't absorb into the paper as deeply has fewer nooks and crannies for the pigment to get trapped in.

Mounting to aluminum eliminates the paper shrinkage and while sizing may help reduce the shrinkage, I don't consider shrinkage to be primary reason to size.

I find that a quick coat of PVA diluted 1:1 with water make for a good size after I have a few of layers of gum down.
 

Colin Graham

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If you don't preshrink, the factory size might be adequate, since it's not being compromised by the hot water shrinking step. That's the theory anyway. I know a few printers don't bother re-sizing if they don't preshrink. Personally though I still get staining with unshrunken, drymounted paper.
 

Colin Graham

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BTW, I keep messing around with RGB and Multichannel (just CMY, no K) and can find no measurable differences in the negatives between these separation methods on CS4, regardless of the order of conversion and inversion. I'd be really interested if other versions of PS give different results. It's odd, since the positives of RGB and CMY multichannel look vastly different. CMYK of course gives very different results, both visibly and measurably different, and is dependent on the order of conversion and inverting.

5030205372_7ec2c1c258_z.jpg


The prints on the bottom row aren't great examples, but they illustrate the better separation and saturation from the cmy(K) version. The RGB(multichannel/CMY) negatives seem incapable of rendering the same intense colors. You can see how the CMYK negatives seem to open up to allow the saturation through, especially in the duck bill and body. In the top 3 rows the channels are in order- C,M,Y.
 
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PVia

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Dave, your prints look great.

I think what you're seeing is a problem that seems to show up in many final coats, whether it be magenta as in your case or blue as in mine.

I coat pure gums Yellow-Red-Blue, with no size, and no shrinkage for prints up to 8x10 or so.

That third coat can be tough to lay down, but I find that a soft foam roller can do wonders for the smoothness, esp for the 3rd layer.
 

Loris Medici

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Colin that's nice - thanks for the trouble. I find myself often upping the saturation for RGB separations. And let me tell you: it works! All depends on your pigments and pigment saturation... I don't think there's an absolute correct way of doing it; depends on your materials / work flow and (ALSO) image / purposes...

Regards,
Loris.
 
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Davec101

Davec101

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Dave,

Sizing the paper with gelatin fills in between the paper fibers so that the paper is less absorbent. The emulsion can't absorb into the paper as deeply has fewer nooks and crannies for the pigment to get trapped in.

Mounting to aluminum eliminates the paper shrinkage and while sizing may help reduce the shrinkage, I don't consider shrinkage to be primary reason to size.

I find that a quick coat of PVA diluted 1:1 with water make for a good size after I have a few of layers of gum down.

So if i read you correctly Rob, i could lay down a size such as PVA after say a second gum coating whilst still having the print attached to aluminium? I like having the ability to avoid registration issues that bonding to aluminium provides especially as i would like to eventually like to print quite large gum prints in addition it seems so much easier get a good coat down whilst its attached to a flat surface.

thanks
 
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