COT-320 and Palladium

In the Vondelpark

A
In the Vondelpark

  • 0
  • 0
  • 18
Cascade

A
Cascade

  • sly
  • May 22, 2025
  • 2
  • 0
  • 18
submini house

A
submini house

  • 0
  • 0
  • 49
Diner

A
Diner

  • 5
  • 0
  • 93
Gulf Nonox

A
Gulf Nonox

  • 10
  • 3
  • 116

Forum statistics

Threads
197,819
Messages
2,764,946
Members
99,481
Latest member
chopfalne
Recent bookmarks
0

TheFlyingCamera

Membership Council
Advertiser
Joined
May 24, 2005
Messages
11,546
Location
Washington DC
Format
Multi Format
I've been playing around with two different paper types I got with my first ever Palladium kit. I got the Cranes (the big advantage of the Cranes is that it is a much faster medium - the downside is the stuff dissolves worse than generic paper towels when wet) and the COT-320. I have a couple of questions about the COT-320. I notice there are two distinct sides to the paper - one smooth, the other coarse. I have been coating my emulsion onto the smooth side, but my prints seem to still be soft and have too much of a paper texture showing up when dry. Should this be happening, or do I need to do something in addition to avoid this, like re-sizing the paper?

I've built my own UV lightbox more-or-less - I got six 24" bl-b tubes from Home Depot, and mounted them to the underside of my enlarger table. The lamps are very tight to each other, as I've read about in various descriptions of how-to-build descriptions. I've got the shelf where I put my contact frame about 12" or so from the lamps. It seems like my exposure times are somewhere north of 15 minutes, but I've only had real success in printing using direct sun exposure to date. Do I need to modify my setup in any way to improve my results, or do I just deal with 20 minute exposure times?

Also, how do you gauge proper exposure under blacklights? I have a decent idea when something is properly exposed using sunlight, as I can see the brown darkening. Any tips at all will be greatly appreciated.
 

Jeremy

Member
Joined
Oct 26, 2002
Messages
2,761
Location
Denton, TX
Format
Multi Format
TheFlyingCamera said:
I've got the shelf where I put my contact frame about 12" or so from the lamps. It seems like my exposure times are somewhere north of 15 minutes, but I've only had real success in printing using direct sun exposure to date. Do I need to modify my setup in any way to improve my results, or do I just deal with 20 minute exposure times?

Why is the contact frame so far away? My frame is only about 3-4" down from the bulbs; I get even lighting and much faster exposure times.
 

Kerik

Member
Joined
Nov 24, 2002
Messages
1,634
Location
California
Format
Large Format
TheFlyingCamera said:
I have a couple of questions about the COT-320. I notice there are two distinct sides to the paper - one smooth, the other coarse. I have been coating my emulsion onto the smooth side, but my prints seem to still be soft and have too much of a paper texture showing up when dry. Should this be happening, or do I need to do something in addition to avoid this, like re-sizing the paper?
You shouldn't have to re-size a paper like COT 320. I'd have to see a print in person to answer your other question. Have you seen pt/pd prints up close and in person before? If so, do these look different? How are you coating the paper?

TheFlyingCamera said:
I've got the shelf where I put my contact frame about 12" or so from the lamps. It seems like my exposure times are somewhere north of 15 minutes, but I've only had real success in printing using direct sun exposure to date. Do I need to modify my setup in any way to improve my results, or do I just deal with 20 minute exposure times?
20 minutes is on the long side, but first tell us about your negatives. (FYI, I use FP4, HP5, and Forte films processed in Rollo Pyro. My negs usually print in 6 or 7 minutes or less under a bank of 40W BL tubes.) Also, you can move the contact print frame much closer to the bulbs (2-4 inches). Your times will be shorter, but maybe not as much as you'd expect. The inverse square law doesn't apply to a large bank of lights, it applies to a point source.

TheFlyingCamera said:
Also, how do you gauge proper exposure under blacklights? I have a decent idea when something is properly exposed using sunlight, as I can see the brown darkening. Any tips at all will be greatly appreciated.
Why not just pull the frame out from under the UV and turn on the room lights?

Good luck. You're on your way...

Kerik
www.kerik.com
 

wm blunt

Member
Joined
Jul 13, 2003
Messages
171
Location
Missouri
Format
Large Format
Sounds like you have your print frame too far from light, 12 inches is pretty far. Use test strips to determine exposure time. Cot-320 should be pretty smooth, how are you coating? Sometimes too much brush work can raise the nap or fibers of the paper.
 

colrehogan

Member
Joined
May 11, 2004
Messages
2,011
Location
St. Louis, M
Format
Large Format Pan
wm blunt said:
Sounds like you have your print frame too far from light, 12 inches is pretty far. Use test strips to determine exposure time. Cot-320 should be pretty smooth, how are you coating? Sometimes too much brush work can raise the nap or fibers of the paper.

The same thing can happen if you've moved your coating tube across the paper too many times.

Also, have you dried your paper thoroughly after coating it?
 
OP
OP
TheFlyingCamera

TheFlyingCamera

Membership Council
Advertiser
Joined
May 24, 2005
Messages
11,546
Location
Washington DC
Format
Multi Format
Many thanks to all...

I'm coating with a puddle pusher. I got the 12" distance from some reference on how to build the lightbox. I can move the shelf for my contact frame much closer. Negative-wise, I'm shooting FP4+ (or Arista 125 in 8x10, which I assume is the same animal in a different label), processing in PMK Pyro, when printed on silver paper, they are printing somewhere between a 0 and a 1 for grade (55 yellow filtration on my dichro head).

I think the paper is dry enough before printing - it feels dry to the touch on both sides, and I'm drying it with a hairdryer.

I got the palladium kit from Bostick & Sullivan.

I just got a new contact printing frame from Photographers' Formulary, and a smaller puddle pusher to coat some for 4x5 negs. I'll try moving the shelf for the printing frame a lot closer to the bulbs and see how it goes.
 
OP
OP
TheFlyingCamera

TheFlyingCamera

Membership Council
Advertiser
Joined
May 24, 2005
Messages
11,546
Location
Washington DC
Format
Multi Format
Ok -

I moved the contact frame to about four inches from the lamps - I'm still getting long exposures (15+ minutes) but I'm getting much better dmax on my prints, and an overall better print. Here's an example... I do have a question though- is this much graininess in the print normal? Or is this just something I'll find on a negative-by-negative basis?

http://www.theflyingcamera.com/photos/JStreeLEBSF.jpg
 

colrehogan

Member
Joined
May 11, 2004
Messages
2,011
Location
St. Louis, M
Format
Large Format Pan
The graininess could be because the paper isn't completely dry. I know, you think your paper is dry. I've thought that some of my papers were dry, but they came out similarly to yours and there's not that much grain visible in my negative (at least not visible to me). How long are you drying your paper?

See the sky in this picture: http://dianemaher.fotopic.net/p11879189.html
 
Joined
Sep 7, 2002
Messages
623
Location
Sacramento
Format
Medium Format
Scott,

You may be having problems with too much heat, too little coating solution, poor coating technique, and possibly expired chemicals. It's also possible that the grain was caused by using too much contrasting agent (trying to print a negative that is too flat for the process).

It's really hard to tell what may be the culpret from the scan, but based on your posts, I can suggest a few things to try.

A 15 minute exposure may be about right for the typical PMK developer, especially if you do a post-development dip in the used developer (don't do this, as it merely increases the exposure time with no benefit to the image quality). I would think about going to a different developer that is less prone to nonproportional stain.

Are you double coating the paper? That normally doesn't work too well with a rod. With a rod it is possible to use much too little solution when coating, which can result in weak blacks, and some uneveness and mottling to the image, but typically not grittiness.

Grittiness can come from overheating the paper, and also from the amount of restrainer you are using. It can also be caused by coating technique. It sounds like you have enough contrast, so I would try letting the paper air dry for about 30 minutes with no heat and see if that affects the quality. If you do use the hair dryer, have the heat setting at the lowest level, or off to avoid too much heat.

If you do use a blow dryer, don't start with it until the surface of the paper no longer has the sheen of the liquid on it (wait until the paper goes 'velvet'). You may be drying some of the solution on the surface, and then when you develop, it washes away, resulting is a bit of grain in the image.

When I first started, I got the most miserable images with all kinds of problems like you are experiencing. The experience you gain from the first few printing sessions will quickly help eliminate a lot of the technique problems that you may be experiencing, so I recommend you keep at it, and try to modify your methods a bit to see where you can improve.



---Michael
 
OP
OP
TheFlyingCamera

TheFlyingCamera

Membership Council
Advertiser
Joined
May 24, 2005
Messages
11,546
Location
Washington DC
Format
Multi Format
Michael-

Thanks for the advice. After reading your remarks, it probably does have to do with the amount of heat - while I do use the cool air setting on the blow-dryer, I've not been using it exclusively, and I've probably rushed the paper into production.

I don't think it is expired chemicals - my set from Bostick & Sullivan is about three weeks old, and is stored in my darkroom, which is air-conditioned and quite dark when I'm not working around it, as it is in the basement.

The negative is definitely not too flat - the scene is a very high-contrast scene. I'm not doing the post-processing dip. I learned after about my third batch of film in Pyro that Gordon Hutchings himself had repudiated that technique, so I quit doing it some time ago.

I'm single-coating my paper, since this is my first ever batch, and I wanted to stretch my learning curve. The mix I've been using is 3:9:12 drops (#1,#2 FeOx and #3 Pd), to coat a 5x7-ish area for printing a 4x5 neg. I switched to a glass rod for coating because I was having problems when working with the Crane's paper of the foam brush lifting up balls of paper. I'll give the brush another try on the COT, since that paper is so much more durable.
 

Joe Lipka

Member
Joined
Sep 24, 2002
Messages
908
Location
Cary, North
Format
4x5 Format
PUT DOWN THE FOAM BRUSH AND BACK AWAY FROM THE COATING....:D

No good can come from a foam brush. The puddle pusher is better, the Richardson Brush is best. You might want to look at your drop count. Weak blacks might come from not enough sensitizer solution.

I let my COT 320 air dry for at least three or four hours, sometimes overnight.
 

Kerik

Member
Joined
Nov 24, 2002
Messages
1,634
Location
California
Format
Large Format
TheFlyingCamera said:
The mix I've been using is 3:9:12 drops (#1,#2 FeOx and #3 Pd), to coat a 5x7-ish area for printing a 4x5 neg.
If I read this right, you're using 3 drops FeOx No.1, 9 drops FeOx No.2 and 12 Pd. The FeOx No. 2 is your problem. I suggest you abandon the use of No. 2 and change to either Na2 contrast booster in the sensitizer or dichromated potassium oxalate developer.

Also, if you need that much No. 2 to acheive the contrast you desire, your neg may be too flat to produce a really fine pt/pd print.

Finally, you may want to try out a Richeson Series 9010 Watercolor Wash brush for coating (aka The Magic Brush by those who use it).

Good luck!
Kerik
www.kerik.com
 
OP
OP
TheFlyingCamera

TheFlyingCamera

Membership Council
Advertiser
Joined
May 24, 2005
Messages
11,546
Location
Washington DC
Format
Multi Format
Kerik said:
If I read this right, you're using 3 drops FeOx No.1, 9 drops FeOx No.2 and 12 Pd. The FeOx No. 2 is your problem. I suggest you abandon the use of No. 2 and change to either Na2 contrast booster in the sensitizer or dichromated potassium oxalate developer.

Also, if you need that much No. 2 to acheive the contrast you desire, your neg may be too flat to produce a really fine pt/pd print.

Finally, you may want to try out a Richeson Series 9010 Watercolor Wash brush for coating (aka The Magic Brush by those who use it).

Good luck!
Kerik
www.kerik.com


I'm just using the Pd kit from Bostick & Sullivan, and following their directions. Trust me, the neg is NOT flat. Printing it on a silver-gelatin paper, it requires somewhere between a 0 and a 1 to print without blown-out highlights.

Will most art supply stores carry the brush you speak of?
 

magic823

Member
Joined
Apr 1, 2003
Messages
456
Location
Boise, ID
Format
Multi Format
Joe Lipka said:
PUT DOWN THE FOAM BRUSH AND BACK AWAY FROM THE COATING....:D

No good can come from a foam brush. The puddle pusher is better, the Richardson Brush is best. You might want to look at your drop count. Weak blacks might come from not enough sensitizer solution.

I let my COT 320 air dry for at least three or four hours, sometimes overnight.


I second the Richardson (its actually spelled diffrent than that but I can't rember the correct spelling) brush. You realy can double coat with a rod well, you can with this brush.

NO FOAM BRUSHES!!!!
 
Joined
Sep 7, 2002
Messages
623
Location
Sacramento
Format
Medium Format
Scott,

Based on your mix listed above, I think Kerik is right about at least some of the grain coming from the restrainer in the #2 mix (great minds think alike). If you are using the #2 PD mix (1.2% Chlorate), then you have an awful lot of restrainer in the mix, and restrainer will definately do this to a print.

I don't know how good of a representation the scan is that you have provided, but it looks like you can back way off on the #2 FO, as the highlights appear to be quite hot. One of the things about pt/pd is the very long toe in the response curve, and that typically results in very nice, subtle highlights.

The image you are showing looks more like a silver print than a pt/pd print, which makes me think that you may be trying to get typical silver contrast characteristics at the expense of the tonal range in the print, and also at the expense of the smoothness of the tone.

I can't recall if you looked at the pt/pd prints I had up at the VC Conference last month, but I can assure you that with good technique, the grain you are experienceing will not occur. The key is to understand the limitations of pt/pd, and be sure that you are working to maximize the positive characteristics of the process, and minimize the weaknesses.


---Michael
 

roy

Member
Joined
Sep 7, 2002
Messages
1,324
Location
West Sussex
Format
Medium Format
magic823 said:
I second the Richardson (its actually spelled diffrent than that but I can't rember the correct spelling) brush. with this brush.

Richeson I believe. I had one sent over by Joe's Cheap Art Stuff. I have to confess that I have not used it yet but I will one day !
 
OP
OP
TheFlyingCamera

TheFlyingCamera

Membership Council
Advertiser
Joined
May 24, 2005
Messages
11,546
Location
Washington DC
Format
Multi Format
Michael-

I did see your prints at the VC conference - I guess I'm working to what I'm familiar with, and what I have as reference prints, which is largely silver prints. Please bear in mind that the image I scanned is about the fourth or fifth Pd print I've ever made, so I'm in the beginning stages of learning the medium. I was guessing at the mix I should use based on the instructions that came along with the Bostick & Sullivan Pd kit - I was getting a print I was happy with on silver paper printed at around grade 0- 1/2, so I was using the amount of the #1 and #2 recommended by their chart. I'll try a more temperate mix and print again tonight. Perhaps a 6:6 mix of #1:#2, or should I go even farther toward #1?
 

Kerik

Member
Joined
Nov 24, 2002
Messages
1,634
Location
California
Format
Large Format
TheFlyingCamera said:
I'll try a more temperate mix and print again tonight. Perhaps a 6:6 mix of #1:#2, or should I go even farther toward #1?
If you neg is as contrasty as you say, I would start with only FO #1 and palladium. Leave out the No. 2 unless you need it. In the mean time, look into the other contrast control methods that have been discussed. FO #2 is not the way most people print these days due to the exact problems you're having. FO #2 is fatal to print quality on some papers, including Arches Platine. COT 320 is made by Arches and is very similar to Platine.

As Michael suggests, a pt/pd print is not going to look like a silver print. It should have a softer, gentler tonality to it. If you're going for a high contrast Ansel Adams kind of look, stick with silver gelatin.

Here's info on using the Magic Brush from my workshop manual:

"The Magic Brush is used quite wet and very little sensiter becomes soaked into the bristles, so there is much less waste than with other brushes. To use, soak the bristles with water, then shake gently a few times. If the bristles start to separate, you?ve shaken out too much of the water. Lay down the bead of sensitizer on the right-hand side of the paper then spread it across the paper from right to left in quick, parallel strokes. Then make a series of strokes perpendicular to the first, then repeat this process until the paper is coated smoothly and the sensitizer is completely worked into the paper. The Magic Brush is so soft that it is nearly impossible to abrade the paper with it. These brushes are expensive (and are worth every penny), but with proper care will last for many years. Rinse the brush thoroughly after each print. At the end of a printing session, rinse the brush well, soak the bristles in fresh HypoClear for a few minutes then rinse with a final dip in distilled or deionized water. Dry off the metal ferrule to prevent it from rusting."

Good luck
Kerik
www.kerik.com
 

photomc

Member
Joined
Jul 20, 2003
Messages
3,575
Location
Texas
Format
Multi Format
Kerik said:
Here's info on using the Magic Brush from my workshop manual:

www.kerik.com

Thanks for that info Kerik...best description I have seen in writing on how to use the brush. Learning quickly that a 1 inch bursh might work fine for 4x5, but after that a 2,3,4 looks much more helpfull. Would guess this holds true for methods other than plt/pld as well?
 
OP
OP
TheFlyingCamera

TheFlyingCamera

Membership Council
Advertiser
Joined
May 24, 2005
Messages
11,546
Location
Washington DC
Format
Multi Format
Many many thanks all... I got some much better prints this evening. I cut the FeOx#2 in half for one print, and eliminated it altogether for a second, and got far superior results. I'll post scans when I can do them- right now the prints are drying. Just wanted to give a big thanks for everyone's helpful feedback.

I ordered two brushes, the 1" and the 2" from that Richeson manufacturer (Joes Cheap Art had the better price of the two mentioned, by about $1-2 per brush). Until then, I'll stick to single-coating with my glass puddle pusher.
 
OP
OP
TheFlyingCamera

TheFlyingCamera

Membership Council
Advertiser
Joined
May 24, 2005
Messages
11,546
Location
Washington DC
Format
Multi Format
Better Samples...

Ok- here goes. I made two more prints last night, changing the amount of the restrainer. Here is the same image as last time, but with a 6:6:12 mix.

http://www.theflyingcamera.com/photos/JStreeLEBSFimproved.jpg

There is still graininess/blotchiness in the darker midtones, but greatly improved. I probably could have stood to let it dry even longer (this one I let air dry for about 45 mins, and hit with the cool air only setting on my blowdryer for an additional 5 mins).

Here is another image I shot at the same general location, printed with 12:0:12 mix:

Dead Link Removed

(note - there is much more grain apparent in the scan than is visible in the print - Also, I tweaked the scan a tad in Photoshop to burn in the blown-out edges - it is a bad negative that shows a lot of development surge at the edges, and it's a shame, really, because it is a great scene. Next time I go back, I'll remember to re-shoot, and tray develop. Probably even bring the 8x10, so I'll have a good-sized negative to work with. )
 

Allen Friday

Member
Joined
Mar 30, 2005
Messages
882
Format
ULarge Format
I pulled out my B&S "Platinum and Palladium Printing Instructions" which came with the kit I ordered several years ago. The last page contains the "Contrast control Chart." You stated above that the neg prints well on silver paper between grade 0 and 1. According to the chart, the mixture for grade 0 is: 18-4-14. The mixture for grade 1 is 15-7-24 (for an 8x10 print). The mixture you initially used closer to the recommendation for a grade 4 print, 6-16-24. Apparently you are not "following their instructions."

Dick Arentz lists 6 causes of graininess in the latest edition of his book on plat. pall printing. The ones that may apply to your case are 1. Materials at too low a temperature. 2. Too much Restrainer. 5. Unsuitable paper. 6. Too much ferric Oxalate.

I would recomend starting from scratch. Review the B&S instuctions carefully. Follow them exactly to get a base print. If the problem still occurs, then start changing the variables mentioned in Arentz' book to eliminate the grain.

It is difficult or impossible to tell from the scans what the problem is. I recommend you read Arentz' book to learn more about the process. He states: "Graininess from the negative should not be confused with the granualrity found in the platinum or palladium emulsion. This can be a serious problem, to the point of degrading certain images. Methods to avoid this are covered in Chapter 7: Choosing Your Method, chapter 10: Advanced Technique, and Chapter 11: Problems."
 
Photrio.com contains affiliate links to products. We may receive a commission for purchases made through these links.
To read our full affiliate disclosure statement please click Here.

PHOTRIO PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Ilford ADOX Freestyle Photographic Stearman Press Weldon Color Lab Blue Moon Camera & Machine
Top Bottom