New and improved Hypercat

c6h6o3

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do you get the solvents from the Chemistry Store?
 

john_s

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I buy TEA from a local company (Melbourne, Australia) who manufacture specialized lubricants. It's also used in soap manufacturing, including home/cottage type operations.

Propylene glycol is used in the refrigeration industry. It's used as a heat transfer agent in the food industry, and according to one web site, leaks of refrigerant do not spoil the product. It is an allowable food additive in some countries.
 

c6h6o3

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jdef said:
This new version of Hypercat should be perfectly suited to the work you're doing.
Click to expand...

I actually prefer less edge effect than most. That's why I like 510 for my
occasional semi-stand Tmax negative rather than Pyrocat. It increases local contrast without the exaggerated unsharp masking effect.

For 90% of what I do I still "love the smell of Harvey's in the morning". Or any other time of day for that matter.
 

aligndont

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new hypercat

From an imaging point of view, how is the new hypercat an improvement over the original formula? Also, is the formula for secret sauce available - sounds quite interesting.
 

aligndont

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How is the new hypercat an improvement over the old formula form an imaging point of view? Is the formula for secret sauce available- sounds interesting.
 

aligndont

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Jay, I will try, if time allows, the new hypercat this weekend. I have to admit that I am very satisfied with the original formula. Any guidance with developing times compared to the original or other developers? I'll let you know on this thread how things work out.
 

Ryuji

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So the formula is essentially 4.5mg ascorbic acid, 0.9g catechol and 18g sodium carbonate in a liter of water.

What's the role of the 4.5mg of ascorbate?

What's your target pH?
 

john_s

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Ryuji said:
So the formula is essentially 4.5mg ascorbic acid, 0.9g catechol and 18g sodium carbonate in a liter of water.

What's the role of the 4.5mg of ascorbate?

What's your target pH?
Click to expand...

Isn't it 45mg?
 

john_s

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Jay, I would have expected a little less film speed, given the lower amount of ascorbate and the absence of phenidone. Have you found this not to be the case?
 

aligndont

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Jay,I tried the new hypercat with delta 100 at ie 80 as follows: 1.5 ml sol.A, 15ml sol.B in 300 ml. distilled water 21 C in 500 ml tank. 1 minute initial gentle agitation followed by 2 gentle inversions per 6 minutes. Tried your suggested dilution but found the developer too active for my taste. I have yet to print the negatives. I, incidentally, found that A solutuion has a clear light brown coloration. From negatives developed in the more concentrated dilution I found results too contrasty but exceedingly sharp. Michael
 

aligndont

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Sorry, Forgot to note that total time of development was 18 minutes.
Michael
 

aligndont

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additional impressions derived from test strips: Using a Heiland split contrast system and a focatar lens most negatives had indications of 2 grade ( or close to ) contrast, were very finely grained, had that 3D look of pyro, smooth tonality, and terrific sharpness. Next time I will probably cut developing time by 10%. My enlarging head was at least high enough to print 11 X 14. I prefer longer developing times ( higher dilutions ) - possible compensation, possibly more accutance, relaxing.
 

Canuck

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Just wondering Jay if you have tried it as a single concentrate using TEA much like 510-Pyro? Thinking of playing but like the convenience of a single concentrate.

Elvis
 

gainer

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Jay, have you seen infectious development? I saw it in a trial of Hypercat with semi stand development. The contrast was too high due to my overdeveloping, but also thin white lines in the picture were made wider. Is there a theory about why ascorbic acid and catechol should work together? Each separately needs fairly high pH to become active, but silver particles act as a catalyst for development. This effect can, I think, cause local contrast to be different from overall contrast. I have used both ascorbic acid and hydroquinone with high pH, lots of bromide and some sulfite as lith developers, but not together. They have noticeable induction periods after which development rate rises exponentially. Have you tested to see the variation of contrast with time?
 

gainer

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Photograph a grid of white and black lines. Something like a piece of black window screen on a white background. How about a window screen with skylight coming through. In the print, the white spaces will be larger if there is infectious development. In extreme cases, the lines can be filled in. When I worked at NASA, we would sometimes see in the proofs of our technical reports where some important narrow traces had been filled in by the developer and etched out by a technician who knew nothing about where the trace should have been. In one time history, time went backward for an instant.
 

gainer

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I agree that "crazy sharp" is descriptive of what I saw. The problem is that it is is much like what I would expect from a lith developer. Grotesque would be more like it. I had a more conventional negative from the same scene and roll, as for my tests I do a 36 exp. roll all at the same time so as to have such comparisons. Granted, the development was too long even for semi stand, but I did not simply get high contrast. There were thin edge highlights that appeared natural with the conventional developers but much wider with Hypercat. The extended gray areas were lighter in some cases and darker in others than the conventional ones. At first glance, I thought I had seen the epitome of artificial sharpening, but if that's what it is, I don't want it except for some special effect. I don't know how well a scanned comparison would fare at low resolution, but when I will try to email you one.

The negatives at low to normal contrast looked fine, but anyone seeking high contrast negatives for alternative printing techniques should try it on a test first.
 

Gerald Koch

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What is being described as "infectious development" is really a misuse of this term. True infectious development occurs in low sulfite developers containing hydroquinone where the sulfite level is controlled by the presence of a formaldehyde or acetone addition complex. An example would be a lithograph developer. Using the term "infectious" is wrong and confusing.

What is being observed here is one of the Eberhard effects. These effects cause quite a bit of trouble in astronomical photography by distorting the size and relative positions of stars.
 

gainer

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Well, catechol is a first cousin of hydroquinone. Sulfite and ascorbic acid act, outwardly, alike in accelerating development rate, even though they do so by different mechanisms. When I see white lines in a print being wider than than adjacent black lines when they should be the same, or otherwise unnaturally wide, I think spreading of the sort encountered in lith developers. It makes little difference what it is called except if one is seeking a cure. I was told (too many) years ago that this effect was a result of the catalysis of the developing action by metallic silver, which we would prefer be limited to that caused by the specks in exposed grains, but which can expand to neighboring unexposed grains. Ascorbic acid should help to prevent such goings on by virtue of its somewhat more acidic oxidized state, but how much? I won't insist that what I saw was actually infectious development, as it might just have been overdevelopment which acted on the optical MTF shape of a step input to make the density threshold appear at a different exposure threshold. Such a thing can happen with any energetic developer. It seemed there were other differences between the results I got with semi stand development in Hypercat that were neither simple edge effects nor the usual effects of high contrast negtives. I think it is pretty certain that the local effects of stand development were more exaggerated in Hypercat than in any othe developer I have seen. The overall contrast I got in this instance, from an extended white to an extended black, was pretty close to normal. Perhaps there is a way to adjust the ratio of ascorbic acid to catechol so as to tune this effect, if it was not just my 78 year old imagination, to suit different situations. If that is so, it would be easy enough to make separate stocks of ascorbic acid and catechol in glycol. De Beers revivus.
 

aligndont

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Semi-stand withe hypercat new

With reference to the question of infectious development or other possible distortions created by this developer with reduced agitation I would like to offer this observation: my experience so far, as I described, yielded images without unnatural widths or contours in contrasty lighting. Some of my test shots included a white trellis in front of dark folliage, black fence rails against
a very light background, all in direct light. Is it possible that my use of a tabular film ( Delta 100 35mm) inhibited distortions with semi-stand developer?
I would also mention that there were no frames with uneven development that I could see.
 

Gerald Koch

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There are several variations on the Eberhard effect and they each have different names depending on who first described them. They cause problems when accurate measurements must be taken from a negative. For example, measuring the separation of two stars on a photograph. The effect causes the images to be farther apart than they actually are. Another variation, a small dark area adjacent to a larger area will be smaller than it actually is, while a similar isolated area will appear larger. It all has to do with the release of restrainers (bromide ion or developer oxidation products) and the local depletion of developing agent.
 

Kirk Keyes

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Sure - what's the link?
 
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