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Thread: Hypercat vs Pyrocat MC

  1. #1

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    Hypercat vs Pyrocat MC

    For those of you who are curious about the real differences between Hypercat and Pyrocat MC, I have some curves that demonstrate their respective characteristics in a very graphic way.

    A friend was kind enough to email me some curves Sandy King posted for some of the litter of Pyrocats, and I have a curve for Hypercat that makes for an interesting comparison. King doesn't give information regarding developer dilution, or temperature, but being somewhat familiar with his testing practices, I'll speculate that the dilution
    is the standard 1:1:100, the development temp is 72F, and agitation is rotary, probably in BTZS-type tubes.

    The Hypercat curve was generated as follows:

    Film-FP4+

    Developer-Hypercat

    dilution- 1:3:200

    time- 7:30

    temp.- 70F

    agitation- Rotary, Jobo

    densitometry- blue diffuse


    About dilutions and concentrations

    While Hypercat and Pyrocat MC are very similar in formulation, it can be confusing to decipher their respective dilutions, because Hypercat is 2X as concentrated as Pyrocat MC, and Hypercat uses a 20% sodium carbonate solution as its B solution, while Pyrocat MC uses a 75% potassium carbonate solution. For clarity of comparison, the developers as tested contain/ liter of working solution:

    Pyrocat-MC

    catechol .5g

    metol .025g

    ascorbic acid .04g

    potassium carbonate 7.5g



    Hypercat

    catechol .5g

    ascorbic acid .025g

    sodium carbonate 3g


    The curve for Hypercat was generated during tests for optimum carbonate concentration. All of the tests were developed identically in my Jobo ATL 2 Plus processor, for 7:30/70F, but the carbonate concentration varied from 1:1:200-1:12:200, and it is the carbonate concentration that appears where development time usually does. So, where it says "Curve=3:00", that indicates the dilution was 1:3:200, and not that the film was developed for 3:00 minutes.


    similarities

    Contrast and SBR are equivalent for a common paper ES, flare density, and speed calculation method.

    Differences

    Film speed-

    For an equivalent normal contrast, Hypercat gives an EFS (Effective Film Speed) of 160-, and Pyrocat-MC gives an EFS of 125+. This is not a big difference, but might surprise some who have read Sandy's claims that Hypercat loses speed compared to the Pyrocats.

    Development times-

    For normal contrast, an equivalent dilution and development method, Hypercat requires 7:30 min @ 70F, and Pyrocat-MC requires 10:00 min/72F. This might surprise a lot of people, considering Hypercat contains no secondary reducer, and 60% less carbonate than Pyrocat MC.

    Stain-

    Hypercat produces more image stain than Pyrocat MC. Metol and ascorbic acid both reduce stain formation, and Pyrocat MC contains more than 2X as much combined ascorbate and metol, as the ascorbic acid content of Hypercat.

    Fog-

    Hypercat produces less fog than Pyrocat MC, probably because it uses less than 1/2 as much alkali as Pyrocat MC. Didn't Haist say something like -"If you have too much fog, you have too much alkali"?

    Sharpness-

    Hypercat is sharper than Pyrocat MC. Because Hypercat uses no secondary reducer, it tans and stains more efficiently than Pyrocat MC.

    Grain-

    Hypercat produces finer grain than Pyrocat MC, because it stains more efficiently, works at a lower pH, and contains no metol.

    I think Pyrocat MC is a very good developer, but in my experience, and in comparative testing, Hypercat performs better. There are very few single-agent developers, fewer single-agent tanning/staining developers, and none like Hypercat, that are made up in glycol and produce full film speed.

    The formula:

    Hypercat A

    catechol 10g

    ascorbic acid .5g

    propylene glycol 90ml


    Hypercat B

    distilled water 750ml

    sodium carbonate 200g

    distilled water to 1 liter

    mixing A

    Add the catechol and ascorbic acid to the glycol at room temp, heat to

    125-150F with stirring until dissolved. Allow to cool to room temp

    before storing in a plastic container. The color of the stock solution

    should be clear to very light amber.

    To make a liter of 1:3:200 working solution, add 750ml water, 5ml Stock A solution, and 15ml stock B solution to mixing container, and top up with water to 1 liter. Enjoy.

    Jay
    Last edited by Ralph Barker; 2-Aug-2006 at 10:43.

  2. #2

    Re: Hypercat vs Pyrocat MC

    I dont know Jay, without seeing the family of curves for your test it is hard to compare the two. From your SBR 7 chart I see that you get a b+f of 0.28, this is not any different from what I get with pyrocat HD. I would suggest you post the curve for Sandy's SBR 7.4 along with yours so we can make a better comparison, since I am unable to see what you acertain. Your IDmin is 0.39, taking a guess from Sandy's family of curves his IDmin seems to be about the same....so, I am having a hard time seeing your claims from these curves you posted.

  3. #3

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    Re: Hypercat vs Pyrocat MC

    I'd suggest that if would like these "comparisons" to be worth anything, you go to the trouble of testing both under indentical conditions instead of simply publishing someone else's tests without their permission. The fact that you haven't bothered to actually test both yourself under indentical conditions makes any conclusions completely without basis.
    Last edited by Don Hutton; 2-Aug-2006 at 05:49.

  4. #4

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    Re: Hypercat vs Pyrocat MC

    Given the history of Jay and Sandy, the only beleivable tests are going to come from a much removed third party. I realize that pyro developers have something of a finite pool of consumers to draw from, but the oneupmanship and vituperation are starting to feel like the Cola wars.

  5. #5

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    Re: Hypercat vs Pyrocat MC

    Quote Originally Posted by Colin Graham
    Given the history of Jay and Sandy, the only beleivable tests are going to come from a much removed third party. I realize that pyro developers have something of a finite pool of consumers to draw from, but the oneupmanship and vituperation are starting to feel like the Cola wars.
    I fully agree with you. Even I am getting sick of this staining developer discussion and may start looking for a good traditional alternative.

    In this case, however, in the start of this thread there is a clear violation of intellectual property rights and I have sent a message to the LF forum informing them of that fact. The rules of participation at both APUG and the LF forum protect intellectual property rights.

    1. APUG
    APUG.ORG Terms of Use Agreement
    http://www.apug.org/forums/faq.php?f...q_new_faq_item

    4. The APUG Services contain Content of Users and other APUG.ORG licensors. Except for Content posted by you, you may not copy, modify, translate, publish, broadcast, transmit, distribute, perform, display, or sell any Content appearing on or through the APUG Services.


    2. LF Forum statement on intellectul property rights
    http://www.largeformatphotography.in...right_faq_item

    What About Intellectual Property Right
    By submitting materials to this site, you you are representing that are you are the owner, or are authorized by the owner to do so. As a consequence, all the material posted in this site is assumed copyrighted by their respective authors, and shouldn't be reproduced without permission and proper credit by any means, including framing.



    Sandy King

  6. #6

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    Re: Hypercat vs Pyrocat MC

    Jorge,


    I use 35mm film for my testing, which has a base density of about .2, and Sandy uses 120 or sheet film, which have far less base density, as you know. I'm not sure how the BTZS softwatre calculates B+F, but my density for step 21 is .23, and I don't know how B+F can be higher than that. I don't know how to separate out one curve from the family Sandy posted without his raw data, but I don't think it's too difficult to look at his SBR 7.4 curve separately, and compare the data for that curve against mine.

    Don,

    I have tested both developers under identical conditions; exposing my tests in my sensitometer, developing them in my Jobo ATL 2 PLus, and measuring them with my Noritsu DM-1 densitometer. I can't make conditions any more identical with my facilities, which are more than adequate to the task. I used Sandy's data for his developer, which he claims it's accurate, useful data, and my data for my developer, for which I claim the same. Sandy always attacks my testing to refute my data, and I thought it might be interesting to see the two side-by-side. I can post my own data for both developers, but my data for Pyrocat MC is substantially similar to Sandy's. The fact that you put comparison in quotes, and assumed I haven't "bothered" to do my own testing reveals your own biases very clearly. Some people believe what they want to believe, and for them, comparative data is a waste of effort.

    Colin,

    it is in no one's interst to post faulty data for their own developer, which is one reason I used Sandy's data for his developer. If we post faulty data, our developers will not be effective in use. It just doesn't make any sense to do that. I posted this comparison because Sandy has made a lot of theoretical claims for my developer that are not borne out in testing, or in actual use. If I simply said, "Sandy is wrong about my developer", without providing any data, I assure you I would be roundly criticized for it. Anyone who cares enough about this comparison to want to know the truth of it, can perform their own tests, as both formulae are published, so you don't have to take my word for it, or Sandy's.

    Jay

  7. #7

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    Re: Hypercat vs Pyrocat MC

    Sorry Jay

    I actually have trouble believing that you have tested them under identical conditions - if you had, I don't understand why you wouldn't have used that data instead of simply purloining Sandy King's data? Seems very odd that you would rather publish inoformation here which is of no merit ("integrity"?) due to potential process differences if you already have the identical data.

  8. #8

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    Re: Hypercat vs Pyrocat MC

    Sandy, you're back!

    I knew you couldn't stay away, it's too much fun here. I'm not sure you have a legal leg to stand on regarding intellectual property rights, as you gave permission to use your data at apug, without giving any limitations or restrictions. Have I misrepresented your data in some way, or are you just not pleased with the comparison? If you're looking for a good non-staining developer, I can make a few suggestions.

    Jay

  9. #9

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    Re: Hypercat vs Pyrocat MC

    Don,

    Sandy cannot refute his own data. It's that simple. He claims it's accurate and reliable, so what's the problem? BTZS testing removes "potential process differences" to the extent that's possible, and Sandy has written about the transferrability of this kind of data. I'd be happy to post my own data for Pyrocat MC if it will make you more comfortable, but I suspect that would be a wasted effort where you're concerned. If you don't like my data, or Sandy's, generate your own and post your results for the rest of us.

    Jay

  10. #10

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    Re: Hypercat vs Pyrocat MC

    D76 anyone?
    Brian Ellis
    Before you criticize someone, walk a mile in their shoes. That way when you do criticize them you'll be
    a mile away and you'll have their shoes.

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