PC-TEA questions?

[baachitraka]

I have mixed PC-TEA rather in a clumsy way and developed a roll of ORWO UN54+ for 8 minutes which came fully developed and contrasty.

- 100ml TEA.
- 9g ascorbic acid
- 0.25g phenidone

I have few questions on the ingredients,

- Will adding more ascorbic acid have any effect on contrast?
- Shelve life of Phenidone. I have in 50g and I am sure it will take very long before it is use it completely.
- Shelve life of ascorbic acid grains.
- Few grains of undissolved ascorbic acid still in the bottle. May I know whether it effects the developer?

* Shadow detail is very nice and will test APX 100 soon.

 

[Alan Johnson]

(1) Adding more AA will not have a significant effect, within reason.
http://unblinkingeye.com/Articles/Synergism/synergism.html
(2) I have some phenidone in a plastic container that is about 15 years old and has gone a bit yellow but still works. After 10 years I bought a new sample to use.
(3) At least a few years if dry, IMO.
(4) No effect, see (1).
In my experience PC-TEA gives a bit more grain and a bit less speed compared with Xtol !+0, which could be attributed to absence of sulfite.

 

[baachitraka]

Thanks. The main reason I prefer developers with long shelve life is that I am not a frequent shooter. I know its not a strong reason should prefer based on other characteristics.

- Rodinal is one which sings in overcast day.
- HC-110, I do not know how it compares with PC-TEA.

 

[baachitraka]

Its fun to scratch mix and also it works.
Yes, I understand the reasons behind your suggestion of keeping it simple.

Perhaps it may be the same reason behind caffenol, that not many are sure what is really going in that developer.

 

[baachitraka]

This is incredible stuff for holding the highlights, for tight grain and for maintaining the box speed.

If x-tol is better than this and I may soon setup the replenishing system soon.

 

[idamia]

@baachitraka Could you provide some examples of your results with PC-TEA?

Thanks in advance!

 

[baachitraka]

Sure. Prints have dried and I have put under some heavy books to flatten them and will _scan and post some soon.

 

[idamia]

great!

 

[Gerald C Koch]

PC-TEA, like most concoctions, is a rather arbitrary formula. I suggest buying a bottle of HC-110. It is not a substitute for PC-TEA, but it is a reliable general purpose developer. Keep it simple.

+1

Many years ago either Popular Photography or Modern Photography did a test. They had a group of people arbitrarily mix up a developer from a list of developing agents and accelerants, etc. Sort of like a Chinese menu, one from column A, one from column B, ... The amounts of each chemical were also arbitrary. IIRC all the concoctions produced an image. Were the negatives optimal, hardly.

Concerning the amount of ascorbic acid in PC-TEA this chemical acts as both a preservative like sulfite BUT also as a developing agent. Therefore changing the amount will change the activity of the developer.

These waterless concentrates are interesting. However the lack of water severely restricts their composition. So no sulfite, bromide, an other inorganics. Kodak in their formulation gets around this problem by using adducts with DEA which are soluble. So you will see in the patent DEA.SO2 for sulfite and DEA.HBr for bromide. Woks very well but is beyond the home tinkerer's capability.

 

[baachitraka]

Yeah. I shouldn't have talked high about this developer(chemistry is too complex: why just 9g of ascorbic acid in this case?) but this developer is a beauty in holding the high-lights.
X-tol would have done the same but the shelf life is what attracted me the most.

 

[Gerald C Koch]

Yeah. I shouldn't have talked high about this developer(chemistry is too complex: why just 9g of ascorbic acid in this case?) but this developer is a beauty in holding the high-lights.
X-tol would have done the same but the shelf life is what attracted me the most.

My all-time favorite for arbitrary quantities is the Germain developer where everything is a multiple of 7. To bring good luck to the user? As an example of blind, staggering luck this formula does actually work. However none of the developing agents produce any super-additivity.

http://unblinkingeye.com/Articles/Harvey/harvey.html

 

[baachitraka]

Glycin is prohibitively expensive here in Germany and that had prevented me to mix Harvey 777. Have seen some samples from @Thomas Bertilsson with luminous highlights.

 

[Thomas Bertilsson]

Glycin is prohibitively expensive here in Germany and that had prevented me to mix Harvey 777. Have seen some samples from @Thomas Bertilsson with luminous highlights.

Not that you would be able to mix it anyway, because the manufacturer has never made the recipe public. It is proprietary information of Bluegrass Packaging in Kentucky.
There are other developers featuring glycin that give really nice results, like Edwal 12 and Edwal 10. But if glycin is so expensive and difficult to purchase, then it's a moot point.

 

[baachitraka]

25g sells for €30.35 and that for me is way too expensive.

 

[Rudeofus]

chemistry is too complex: why just 9g of ascorbic acid in this case?)

Ascorbic Acid acts not only as secondary developing agent, it is also an acid. As you add more and more Ascorbic Acid to PC-TEA, pH and therefore activity will decrease. It appears that Pat Gainer found a local optimum here with 90 g/l concentrate.

 

[baachitraka]

I also read that more than 9g of ascorbic acid in 100ml of TEA is hard to dissolve but I don't know how far this is true.

 

[Gerald C Koch]

One must be careful when specifying TEA as there are two main grades of this chemical. There is a technical grade which contains 15% DEA and one which is 99% TEA. The technical grade has a higher pH which can throw off a formula's activity. So it is always good to specify which grade was used. You should get an MSDS when you buy TEA which will give the purity. I buy mine from The Chemistry Store which sells the 99% version.

 

[Rudeofus]

In case it helps baachitraka: Fototechnik Suvatlar also sells the 99-100 % version.

 

[baachitraka]

It was solid when it came by post and dipped the entire plastic bottle in hot water and took 100ml from it for making the formula.

 

[Gerald C Koch]

It was solid when it came by post and dipped the entire plastic bottle in hot water and took 100ml from it for making the formula.

To further complicate matters the two grades I mentioned in a previous post are also available as 85% solutions in water. This solves the viscosity or freezing problem for certain commercial users. The average person on APUG should not encounter them but again always good to read the label or MSDS.

 

[baachitraka]

Here are some scans of the prints. My focotar needs good cleaning nevertheless PC-TEA holds the highlights very well.

*Scans gave muddy tones and I did not adjust the curves and uploading as it is.

 

[idamia]

Given that the curves have not been tweaked, these look really fine!

 

[baachitraka]

Result from diffused light. This stuff is rather very good for any lighting.

APX 100 & PC-TEA for 7'30"

 

[idamia]

I have shot two rolls of Delta400 (120 film; @ASA400) yesterday and want to give PC-TEA a try.

Unfortunately, I can't find dev times.
Any suggestions?

 

[Alan Johnson]

Use Xtol (1+2) times:
http://www.digitaltruth.com/devchart.php?doc=discontinued