Bulk Hypo

[mikepry]

While with a buddy helping him pick up pool chemicals for his job at the pool place I happened to see pallettes with 45lb. bags of hypo. They were labeled Prismatic photo rice crystals! It cost me 35.00 for the bag. No shipping either. So look for a pool supply company cause they use it to de-chlorinate pools if the chlorine level went to high and also it is sold to water treatment plants as well. There is usually a pool supply house in every semi-large town. I try to use Mike @ Artcraft for everything but this is just to good of a savings to pass up. Hope it helps. Best, Mike Pry

 

[fhovie]

That is pretty cool - so do you use it one shot and do you add sodium bisulphate to it? I like the TF-4 from photoformulary but it isn't real cheap. I would have a hard time making the switch though, I like the short wash times and not needing stop bath. - Plus I couldn't use it with PMK. ... (Ph is too low)

Frank

 

[Robert]

If you like TF-4 when not try mixing TF-2? It's not a rapid fix but other then that it's similar to TF-4. My understanding is TF-4 comes with a high capacity but TF-2 is pretty good and cheap if you mix your own.

250 grams of hypo
15 grams of sodium sulfite
10 grams of sodium metaborate

all for 1litre

 

[lee]

why couldn't you use regular hypo with PMK. I use Kodak Rapid Fix without the hardner and have no problems at all. Try it you might find it works for you and it is sure cheaper.


lee\c

 

[avandesande]

This is hit or miss, I visited 4 or 5 pool places trying to find STS with no luck.

 

[fhovie]

</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (lee @ May 20 2003, 04:47 AM)</td></tr><tr><td id='QUOTE'> why couldn't you use regular hypo with PMK. I use Kodak Rapid Fix without the hardner and have no problems at all. Try it you might find it works for you and it is sure cheaper.


lee\c </td></tr></table><span class='postcolor'>
Hi Lee:

It may work but you would need to see a before and after for comparison. As soon as the PMK stained negative hits the low ph of acid fixer, a lot of it (the stain) falls off and it will cost you some density and a loss of the benefits of a good overall stain. The reduced silver will still be there and the negative will print - you just won't get as smooth a print as you might otherwise. I noticed a meaningfull difference in stain before and after the 20min recommended wash. Try some TF4 (ammonium thiosulphate based) and make a few exposures and compare the results against a sodium thiosulphate based fixer - I'll bet photoformulary would send you a sample if you asked them. One other thing - the capacity of TF4 is almost twice that of acid fixer - helps offset the cost a little. If you use it with prints - you wont need stop bath (just water) and your entire process will be a higher ph and more archival. Less wash time! So yes - it is more expensive but overall - worth it IMHO

Frank

 

[c6h6o3]

</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (fhovie @ May 20 2003, 05:23 AM)</td></tr><tr><td id='QUOTE'> benefits of a good overall stain. </td></tr></table><span class='postcolor'>
What benefits? Overall stain acts as fog, effectively reducing contrast. The best overall stain is the least overall stain.

 

[lee]

I have done comparisons before and I can't see it making any difference. None. About it being more archival I don't know about that. Being able to wash it out is another matter. Surface hypo is washed out with turblance and the rest is soaked out over a period of time with paper. With film, 20 minutes should be enough time regardless which fix you end up using.

Stain increased in the wash regardless of the ph of the fix.


lee/c

still not convinced

l\c

 

[mikepry]

</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (fhovie @ May 19 2003, 07:08 PM)</td></tr><tr><td id='QUOTE'> - Plus I couldn't use it with PMK. ... (Ph is too low)

Frank</td></tr></table><span class='postcolor'>
Frank'
I use the Kodak F-24 fixer that is identical to the one that Gordon Hutchins uses and recomends. Isn't he the guy that started this PMK craze? I don't use PMK at all anymore and as far as overall stain I couldn't agree more with the previous post that talks AGAINST overall stain. If you look on page 18 of the Pyro book he not only suggests it, he uses it!

 

[Donald Miller]

I agree with all that has been said about the effects of overall stain. In my experience, overall stain reduces overall contrast. It acts as an increase of B+F. I have even noticed with ABC pyro that if the Bisulfite gets some age that it also imparts an overall stain. The result is the same reduction of contrast. At least with ABC I know what causes it and what I can do to prevent it. In the case of PMK, it is marketed as being something of value. In fact the advertisements that coexist with the Bergger film ads clearly show an overall stained negative. The true benefits of Pyro developers exist in the fact that the tanning is proportional to silver density. Since the low values have little negative density they should have very little in the way of tanning effect from the pyro. The tanning/stain of beneficial pyro formulations will not be immediately visable to a casual observer by just visually examining the negative.

 

[fhovie]

Well guys - there is generally a give and take in most situations. Not having overall stain to print through could be seen as andvantage as far as contrast goes. I see a positive difference in the middle grey tones - zone 5 through 7 - like sky and chrome and metal with the added overall stain. The overall stain reduces the grainieness. IMHO. I have enough chemicals to mix 10 liters of regular fixer. I could go back and re-test. I have some new lighting I want to try and I also have some zone test negs - undeveloped in a box I could try. I am always seeking for improvements - at this time though, my frontier is probably not in the negatives but in the printing. My negatives 4x5 TRI-X in PMK with TF4 are full and rich and easy to print. It is now a matter of new darkroom skills to interperet my negatives in different ways. - Frank

 

[Aggie]

..

 

[sanking]

As a general rule my belief is that overall stain, which functions like b+f, should be avoided. Very high levels of non-image stain may have some benficial results in limited cases but the benefitws with most films and formats are outweighed by the negatives.

Briefly, high levels of general stain result in:

1. longer exposure times
2. lower contrast
3. some grain masksing

On the whole the advantage of grain masking may outweigh the longer exposure times and lower contrast for medium and high speed 35mm films, and for high speed 120 film.

For sheet film of 4X5 and larger size there is rarely a need for grain masking since these films already provide smooth grain at normal enlargement sizes. Therefore, printing negatives 4X5 and larger, even with silver gelatin printing, the longer exposure times and loss of contrast are more signifiant than any grain masking that make result.

For alternative printing where a fairly high Contrast Index is needed, and exposures with UV light are fairly long (even with film with low shadow density), the loss of contrast and longer exposure times are generally unacceptable.

Sandy King





For alternative procesess

 

[Aggie]

..

 

[fhovie]

I must confess - I only use PMK only for 4x5. I use DiXactol for MF (higher cost, less ovarall stain, higher accutance and tighter grain) and split D23 for cute little films. (Very fine grain - high solvent - good accutance) I found tanning developers unacceptable for enlarging very much.
FWIW:
Staining is really different over film types as well. TRI X has a lot of overall stain (which is a benefit for the large grain it has IMHO) , APX100 almost no overall stain. FP4 is minimal. I have never had so much overall stain that it increased exposure times measurably or caused me to jump a paper grade. Most of my subjects these days are N or N-1 and I am certainly not overdeveloping anything.

I have used several kinds of commercial and home brewed fixers and I like the results from TF4. I like the short wash times and not needing to use hypo clearing agent any more. The cost of chemicals is insignificant to the value of my time or the possible value of the print or the cost of the trip.

And ... many folks are not even sure at what ISO speed, their film performs with their chemistry to achieve one zone over B + F for a zone 1 ev anyway. (Which I have done with consideration of the higher overall stain on TRI X)

So hopefully - with all sacred cows now slaughtered .... I'd bet we could all agree that if you can capture 12 stops over B+F with/including a high overall stain and you did get grain masking that will help TRI X print smoother on a 24x20 print, one might find the stain an asset. Now - lets talk about pre-flashing ....... (just kidding)

- I have not done any alternative printing and I am sure different considerations might make any kind of staining developer undesirable. I understand that UV capable densitometers are required to faithfully evaluate PMK negatives and that would lead me to believe that overall stain could be a real issue there. For the Cachet, Forte and Ilford fiber papers I use, the results please me greatly - and are well received by others typically as well.

I guess we are back to the fact that no processes are ALL THINGS TO ALL PEOPLE and each discussion is usefull for the possibilities it opens up to be explored. At least that is the way I find them.

Frank