Questions about sodium Hydroxide as accelerator for B+W graded paper.

Any one know about using sodium hydroxide instead of Carbonate?

How much hydroxide to get the PH to 13 for one liter?

I understand that Hydroxide is unstable as an accelerator??? something about Buffering? please explain.

when you need more contrast when grade 2 is only available.

you already have added double the carbonate. and still not what you quite need!

do you first subject the negative to selenium intensification? or make a developer with Hydroxide instead of carbonate? Now keep in mind we only can consider choices based on using only Grade 2 paper.

take me to school on the Hydroxide accelerator "thang"

thank you in advance,

greg zinselmeier said:

when you need more contrast when grade 2 is only available.

Click to expand...

Overprint and bleach reduce?
Where did you get grade 2 paper? Is it old?
Benzo plus carbonate might get a bit more contrast. Benzo seems to restrain highlights more than shadows. Pot.Bromide tends to reduce contrast.

thanks Don,

this is what I'm using per liter

Phenidone .5g
Sodium Sulfite 30g
Hydroquinone 7g
sodium carbonate 60g
BZT .2g

I have added another 60 grams of Sodium Carbonate. and its just "shy" of what i need. I may add another 7g of Hydroquinone. I understand this adds contrast, where metol
or phenidone is less contrast. so ?????

also it is a stained neg. in pyro cat HD. IDK if the selenium Intensifcation works for or against a stained Neg. ????

The grade 2 paper is Foma. FB new

Here's an interesting thread on increasing paper-contrast:
Increasing Graded Paper-Contrast

greg zinselmeier said:

when you need more contrast when grade 2 is only available.

you already have added double the carbonate. and still not what you quite need!

Click to expand...

Use a different negative. Try a harder paper grade. Switch to VC paper instead.

In all seriousness though, you're expecting something from chemistry it isn't going to give you. Not in this way. Increase pH to 13 and all you get is a soft gelatin emulsion, but not more contrast.

What you might try if it really has to be a chemical solution (no pun intended) is develop the print as it is and then intisify it. For instance chromium intensifier (TOXIC!!!!) allows you to boost the contrast of a silver image. I'm sure there are safer formulas as well.

For a mild contrast boost; print the highlights as you want them but the shadows slightly light and then gold tone. Don't expect anything close to a full or even a half grade boost though.

The chromium trick will let you boost the contrast far more, even repeatedly if need be. The image tone will be greenish though. Print permanence might suffer. Again, it's not a preferred approach in terms of toxicity and environmental concerns. Hexavalent chromium is carcinogenic, a strong irritant and toxic.

greg zinselmeier said:

thanks Don,

this is what I'm using per liter

Phenidone .5g
Sodium Sulfite 30g
Hydroquinone 7g
sodium carbonate 60g
BZT .2g

I have added another 60 grams of Sodium Carbonate. and its just "shy" of what i need. I may add another 7g of Hydroquinone. I understand this adds contrast, where metol
or phenidone is less contrast. so ?????

also it is a stained neg. in pyro cat HD. IDK if the selenium Intensifcation works for or against a stained Neg. ????

The grade 2 paper is Foma. FB new

Click to expand...

The formula above ID-62 is missing the normal 2 gm of Potassium Bromide, you could double this to 4 gm that will help improve the contrast.

Selenium toning the negative will work with negatives developed in Pyrocat hD. Another option is to tine the print with Ilford IT-8 Toner, but this gives quite a colour shift towards Olive Black, it does intensify the print as well, essentially the Bleach is similar to a Chromium Intensifier and the redeveloper a simple Pyrocatechin formula. In practice I use Pyrocat HD at 1 +1 to 25 as the redeveloper and get the same results.



Print - Forte Polywarmtone FB, Developed in ID-78, right half toned in IT-8

Ian

If it's an issue with your negative, just get some higher contrast paper (or vc paper). Especially if you really want to enlarge that negative.

I have 2 full boxes of 20"x16" Kodak Elite B&W paper Grade 2, so printing with a bit more contrast is something I'm giving thought to. I've been using VC papers since Agfa dropped Record Rapid.

One option that I used to use many years ago with graded papers was Ilford ID-14 published as a Press Contrast developer, it does give quite a decent boost in contrast. It's worth noting that Ilford recommend ID-62 normally be used at 1+3, but for higher contrast 1+2 or even 1+1.

Ian

I’m just gonna reshoot and add dev. Time to neg. And be done with it. I was hoping for a chemical switch-r-rue, that would tweak it just enough, but back to the shot!

A couple of tricks I use:

First, I found that selenium intensification for PMK negatives effectively removed the stain and the sum was net zero (removal of stain cancelled out the intensification). So, I now use bleach-redevelop when I need to add contrast to a negative. It is easy and does the job well and you can do this with all the lights on (and works for negatives developed in any developer). Simply make a rehalogenating bleach of potassium ferricyanide and potassium bromide. Bleach the negative until no silver image is left, rise and then redevelop in a staining developer like PMK or Pyrocat. This adds a layer of contrast-wise stain to the negative increasing contrast. Note: this may add graininess to smaller-format negs.

Adding carbonate and BTA to the developer, in conjunction with a stronger dilution often yields gratifying results. I used to keep stock solutions of both on hand just for this purpose (it's really unnecessary with VC papers; just dial in a bit more contrast if needed).

Selenium toning the print adds a bit of density, but not nearly as much as the IT-18 that Ian mentions. Still, a bit of local bleaching of the highlights and selenium toning of the finished print can often give enough extra contrast to get where you want to be.

In the worst-case scenario, you'll just have to bite the bullet and use a different paper. VC papers offer a lot of contrast control...

Best,

Doremus