Graininess with Pt/Pd

[Dan Dozer]

I've just started using a new combination - Bergger 320, Potassium Oxylate, and Na2 for contrast. My initial thoughts are that I like everything except that my first efforts seem to be turning out a little more grainy or fuzzy than what I am expecting. I read about trying things like humidification of the paper prior to coating and using Tween 20. Any one have any other comments or simple suggestions for me to try?

Thanks,

Dan

 

[Ian Leake]

How much Pt/Pd printing have you done in the past? Can you describe what the "graininess" looks like in a bit more detail? Is it in the shadows or the highlights (or both)? What ratio of Ptd are you using? How much NA2? How much coating material and coating area (drops, cc, 8x10, 4x5, etcetera)? And are you using a brush or rod? Lots of questions, I know, but without more detail you'll probably get a host of speculative answers which may not help. For example a common cause of poor quality is insufficient coating material (especially if coupled with over vigorous brushing), but more info on the process you're following is needed to make a diagnosis.

 

[nick mulder]

Similar to Ian's comment>> What combo were you using previously ? And what was the reason to change ?

I recently also started a whole new set of chems/papers/processes and was too interested (oh, ok excited) so went and used them all in one go, I was lucky enough for it to work out (Ziatype and interestingly enough COT320/PotOx/NA2) - If it didn't work out though I would have stripped back the changes to one each time, if in turn the new addition worked then I'd consider this the new status quo and move onto the next change and so on, basically you'd have a process of elimination to find out what element is causing the issue.

 

[TheFlyingCamera]

I'm surprised you're having an issue with that combination - it works exceptionally well for me. Can you post an example of the problem here so we can get an idea of the symptom?

 

[RobertP]

Also make sure you are coating the right side of the paper. Some papers are easy to tell the smooth side by looking at them in a raking light. Then others, like the Swiss Opaline I use, require some very close inspection to determine the right side. I don't use Cot 320 so I can't comment on that particular paper but this is the case with most pt/pd papers I've tried. You'll also find that different papers require different amounts of solution. Like Ian pointed, error on the side of having a little to much solution as opposed to not having enough. Excessive brushing with a low quantity of solution can cause the fibers in the paper to fray/break, creating that fuzzy effect to the surface. But like it has been pointed out, it is really hard to tell considering all the variables involved without actually looking at the print. Robert.....P.S. In most cases if the paper has a water mark it will be on the right/smooth side.

 

[TheFlyingCamera]

COT320 is tough to tell the "good" side. You'll have to do it by feel AND look together. Once you get used to it, it's easy to tell. The "good" side is just a bit smoother, and the paper fibers will be harder to see.

 

[RobertP]

What type of brush are you using.. if you are using a brush?

 

[Dan Dozer]

Lots of questions so here goes on my past and present techniques and experiences.

I've been doing Pt/Pd for about two years now. I initially started out with a B&S kiit and Cranes Planinotype. I started out following all the B&S, Dick Arentz, and any other resources for tips on coating and mixes. I started out with Fo2 which I have now changed to Na2 as noted in my initial thread. I have now been trying Na2 for about a month or so.

I am now trying out Bergger and Weston papers. I got some Cranes Kid Finish and immediately didn't like it much.

The graininess i'm seeing the emost is in some portraits in the areas where it matters most, in the facial features where tones are somewhat even and on the lighter side. Note that the negatives are fine because I've also printed them in silver and they look pretty clear. Could it be that I'm working from negatives that are somewhat thin for Pt/Pd???

I'm using about one drop of Pt to every 5 drops of Pd. Note that I initially started out using only Pd and am now checking out how much it changes the image with some Pt as well.

I'm brush coating and for 8 x 10's, I'm using 18 drops of Fo1 and 18 of Pt/Pd on Bergger 320. It seems to be enough coating material to me. I'm using (and don't laugh here) natural bristle brushes that I got at Home Depot. They are not all that expensive, but seem to do the coating just fine to me. I'm using the brush coating technique that is on Jeffery Mathias's website where you brush one full pass each direction. This gives me four passes total in the brushing and seems to give me very even coverage. I don't think that I'm damaging the paper any in my brushing process - I'm pertty light in the pressure that I apply.

My E-mail access is down on my computer that has my scanner so I can't post anything for now. Maybe I'll try to do something this weekend with it.

Regarding the right side of the paper - that will be something I have to look into. I haven't worried about it until now, but perhaps that is part of the problem. I checked one of my prints (on Bergger) and it appears that the back is a little smoother than the front.

Thanks everyone for the comments and advice.

Dan

 

[rbergeman]

if the neg's good for silver printing there's a good chance it's a bit thin for pt/pd ..... but then, that's what the na2 is supposed to be good for ...... have you tried adding tween and humidifying? those are two standard steps for smoothing out even tonal areas, tho tween seems to lower my dmax .....interestingly, relative to what you're now experiencing, i've just started using na2 on cott 320 for some negs originally exposed for silver (meaning they're about one stop too thin in the shadows), but when i printed them in pt/pd using the A/B method (using more B than A of course) i always had trouble avoiding flocculation in the smooth water surface tones ...... in the past couple of weeks i've tried na2 diluted 1:3 on those two negs, and i find that na2 delivers on the promise of giving baby butt smooth tones above zone 5 (but yields less intense blacks if i also add tween) ...... i think cott 320 is a great paper for good blacks and local contrast in the shadows, but it does tend to be a bit 'grainier' than cranes was in smooth areas .... and it definitely has one smoother side to print on, so be sure to check that out first ..... by the way, you never said how much na2 you were adding to the 18+18 drops of solution (38 drops should be enuf to coat an 8x10, tho it is on the more economical side) ..... well, that's my two cents worth -- keep up the good fight

rich

 

[Ian Leake]

Although I don't print using NA2, my initial thought is also that your negatives are too thin which is making you use to much restrainer to compensate. Try developing a set of negs with sufficient density and see what the difference is.

It's quite easy to work out the correct side of COT320. You don't need to look at it - just close your eyes and run your finger tips over the surface ever so lightly and you'll notice the difference. Once the paper is processed (and all the sizing has floated off) it's much harder to tell.

You've probably got just enough solution to use when your brush is wet but not enough for the first sheet or two. I use 3cc (about 60 drops) for the first sheet I coat as the brush takes up about 1cc. The subsequent sheets get 2cc each until the brush us saturated and then I reduce it a bit more.

 

[Dan Dozer]

Rich - I've been thinking of trying humidifying and tween. I was able to find an old paper comparison on the net that identified the results in adding tween to the coating mix and it varied in increasing or decreasing the Dmax from paper to paper. Unfortunately, it didn't test Bergger. The one portrait that I noticed the problem which was 8 x 10 I used 3 drops of 20% Na2,18 drops of FO, 15 drops of Pd, and 3 drops of Pt. This mix seemed to give me a good range of values and contrast.

Note that I used to use about 24 drops when I was using Cranes, but Bergger seems to require a little less.

Ian - I'm a little confused about your suggestions on the amount varying with the wetness of the brush. My process is to soak the brush in distilled water until I'm ready to coat, then shake/wipe off the water until the brush feels only slightly damp, then coat the paper. This is what I read in Dick Arentz's book. I only coat one sheet of paper at a time. Are you doing muliple sheets? It sounds like it.

Dan

 

[Ian Leake]

Ian - I'm a little confused about your suggestions on the amount varying with the wetness of the brush. My process is to soak the brush in distilled water until I'm ready to coat, then shake/wipe off the water until the brush feels only slightly damp, then coat the paper. This is what I read in Dick Arentz's book. I only coat one sheet of paper at a time. Are you doing muliple sheets? It sounds like it.

Dan

Yes, I coat and dry all my paper at the start of a printing session - typically 6 to 12 sheets. I give each sheet a standard coating with no restrainer and manage contrast control with dichromate in the developer. This has the several benefits: it takes less space, is very time efficient, every print in a session has a consistent coating, and I don't need to worry about ruining negatives with paper that's not dry.

I used to keep the brush in water but I found that introduced more problems than it solved. Too much water and you get streaky prints, too little and the brush takes up chemicals that should be on the paper. I'm not saying don't do it this way (some very accomplished printers use this method), just that it didn't work for me.

 

[TheFlyingCamera]

Dan- 3 drops of 20% NA2? Wow. That's a LOT. I've found the COT320 takes a fair bit less than 24 drops to coat for an 8x10 - about 16. A pt/pd mix for me might be 9 pt : 7 pd : 2 2.5% NA2 : 16 FO. Your brush technique sounds good to me. It is sounding more like a humidity problem. How long are your exposure times and what light source are you using? You could be running into problems with the light source overcooking your prints - in a workshop I took at CFAAHP, they had gotten in a new light source that ran really fast, and was putting out enough heat that it was baking the prints and drying them out while they were exposing. Some of those prints got rather grainy and blotchy. Backing the light source off the prints another couple inches and cutting the power output helped a lot.

 

[clay]

Just an FYI for those using Na2 as a contrast agent: it will only behave properly when used in conjunction with pure palladium in the metal mix. When you start adding the potassium chloroplatinite to the mix, you rob the Na2 of it ability to consume twice as much FO in the reduction reaction - in other words, the platinum Na2 salt converts to K2PtCl6, which is insoluble, and negates its restraining and contrast increasing effect. When you use it in a mix with Pd and Pt, you get a constant ES of 1.5. regardless of the concentration of Na2 used. This is explained in exhaustive detail in the 2nd Edition of the Arentz book in Appendix A.

My naturally skeptical nature led me to test this for myself, and it is indeed the case that Na2 only works as a contrast increasing agent when combined with a pure palladium metal mix.

So, be forewarned, you are flushing expensive Na2 down the drain when you try to use it for Pt/Pd prints. The dichromate laced developer method is the way to get contrast control if you want a mixed Pt/Pd print.

 

[scootermm]

I have to reiterate what the turnip extraordinaire has said about using Na2 in combination with palladium AND platinum... Na2 is intended solely to be used in combination with palladium. Dick Arentz's book on pt/pd states this very clearly, but I also allowed my curiosity to force me to experiment with this and I came to the same conclusion as clay, albeit, without the extensive chemistry lesson, but nonetheless the same... Na2 usage is only intended for use in conjunction with pure pd. Arentz was right, likely shouldn't have questioned that.

 

[TheFlyingCamera]

Clay- do you have any other alternative contrasting methods besides dichromate in the developer for working with pt/pd mixed? I'd rather not use it if possible.

 

[scootermm]

Arentz book thats going to be about the most useful and informational resource you'll come across Scott.

 

[clay]

One thing that I have done for subtle contrast manipulation is to vary the Pt/Pd ratio. Pure Pt is higher contrast than pure Pd, and changing the mix of the two will allow you manipulate the contrast to a degree without using any restrainer. Of course, the more Pt, the more cool-toned the print becomes. If my memory is accurate, I think the exposure scale of pure Pd is something like 2.3-2.4 and the exposure scale of pure Pt is in the 1.5-1.6 range. So mixing the two metals in different ratios will give you some contrast changing effect.

One thing that is often mentioned is the difficulty in achieving a pure Pt print with modern materials. I heard this stated at a workshop one time, so naturally I went home and tested it myself. With the right paper (Buxton or Whatman's) I was able to make some very nice 100% Pt prints. I used fresh developer so that I could keep that variable constant. The funny thing is, I like the color and tonality and smoothness of Pd prints a lot more. So I just have this in my bag of tricks if I ever want to make a neutral print.

The dichromate method is not that bad. I do a lot of gumovers, so I am used to being cautious with dichromates.

 

[Ian Leake]

Dichromates aren't so bad so long as you:

• Avoid inhaling or touching the powder
• Avoid drinking the stock solution
• Avoid allowing any of the stronger developers or the stock solution to touch your skin (it can enter your system through abrasions and cuts in your skin)
• Ensure that no-one else can do any of those things (the Potassium Dichromate stock is a nice orange coloured liquid which may be very tempting to children...)

If you can do this then it's really easy.

I think the higher grades of developer do lead to a slight loss of "glow", but that's an argument for better negative control rather than different chemistry...

As an aside, I found that making pure Pt prints was very useful as it helped me understand much more about what's really going on with Pt/Pd prints.

 

[dpurdy]

I use hydrogen peroxide sometimes. Doesn't seem to take much and I mix pd with pt

 

[TheFlyingCamera]

I have to reiterate what the turnip extraordinaire has said about using Na2 in combination with palladium AND platinum... Na2 is intended solely to be used in combination with palladium. Dick Arentz's book on pt/pd states this very clearly, but I also allowed my curiosity to force me to experiment with this and I came to the same conclusion as clay, albeit, without the extensive chemistry lesson, but nonetheless the same... Na2 usage is only intended for use in conjunction with pure pd. Arentz was right, likely shouldn't have questioned that.

I was just thinking on this statement. I'll freely admit I did not read all the appendices of the Arentz book with extreme attention to detail, so I do not recall the caution about using NA2 with palladium only. In my own printing experience, I have seen an effect when using a blend of Pt/Pd. Perhaps this can be accounted for by the amount of Pd in my blend, or the amount of absorbed Pd in my developer. Perhaps it is a function of the minimal amount needed, and that beyond a certain threshold it becomes ineffective. I can show you two prints of the same negative that use the same pt/pd ratio, the only difference being the inclusion of NA2, and there is a decided contrast difference between them.

 

[RobertP]

And to confuse this even more. When you do add Na2 to the Pd and FO mix it is no longer a palladium print but a Pd/Pt print. It is just that sodium chloroplatinate reduces the FO by something like twice the rate as potassium chloroplatinite. But as Clay points out they will not work together. So technically, which ever method you use, you are adding a platinum salt to the mixture either way. Also if you are using both techniques, the traditional method (chloroplatinite) or the Na2 method (chloroplatinate) do not use the same developer for both. I highly recommend the Na2 method. I think it makes life so much easier. But that is just my opinion. There use to be an article at B&S website going into this in great detail. But since I'm not a chemist I think I fell asleep halfway through it. Robert

 

[RobertP]

Scott , I think what Clay is saying isn't the fact that it won't increase contrast but the fact that you are probably not using all the platinum salts by trying to combine the two. So you are probably flushing a lot of precious metal down the drain. If you are using potassium chloroplatinite you would probably be better served by increasing that mixture to increase your contrast instead of trying to add Na2. Or just go with the Na2 method and increase the Na2 for contrast. Robert

 

[scootermm]

It wasnt in the appendices I do remember that... although cant tell you the exact page number in the main body, Ill double check tonite when I get home and can thumb through the actual book. But just checking arentz website, in the graph listed here it states 6 drop of pd 6 drops of FO and Na2 drops being added in addition to the twelve drop total.

Perhaps the discernible difference you are noticing in the two prints you are referencing is the greater pt ratio to pd ratio... not the chemical characteristic of the Na2 contrast method, but the chemical contrast characteristic of pt to pd
EG: 7 drops of pt (6 drops of normal pt and 1 drop of Na2 pt) to 6 drops of pd ... vs ... 6 drops pt to 6 drops of pd.

 

[RobertP]

Since I do ULF prints I use pipettes. A 2ml pipette for FO and another 2ml pipette for Pd. Then I use a 1ml pipette for Na2. On page 59 of Arentz's book ( second edition) he gives you a chart that works very well if you know the DR. of your negative. I find it a pretty good starting point. But I also have a densitometer. Which makes it much easier. A 1ml pipette will allow you to really dial in the amounts of Na2 . Robert