The Road to Pyro

There's an impossible to define point at which a photographer's natural inclination to try new films and developers starts to transform into a phenomenon popularly known as magic bullet chasing, a quest to find that perfect combination that will give our images that balance of grain characteristics, tonality and apparent sharpness that will finally yield that long sought after look, spurred on by the implicit belief that such a combination exists. Over the years I have tried my fair share of combinations myself, but if there was ever a point that this crossed the line into magic bullet chasing it was the first time I tried Pyro developers back in my 20's.

Don't feel too bad if that's a new on you. Pyro developers started falling out of favour as long ago as the early 1900's, a decline that has everything to do with the introduction of developing agents whose stability and convenience characteristics trumped pyro's image characteristics, an area in which few would argue it has ever been surpassed after more than a century.

So what is this stuff and why should it be worth the bother? First to the what: Pyro developer is a general term for black and white film developers that are based on either Pyrogallol (aka Pyrogallic Acid) or Pyrocatechin (aka Pyrocatechol or simply Catechol). These are normally used in combination with other developers such as Phenidone or Metol. When it comes to why, Pyro images have a few desirable characteristics. The most well known is something that at first blush sounds like the last thing you would want - these developers stain the negative. The important detail that turns what sounds like a disaster into a boon is that stain increases with the density of the image so that the final image consists of the regular silver grain image plus the stain image. Because the stain image is continuous it reduces the appearance of grain. Additionally, there is very little bleeding along edges where light borders dark in the image increasing the appearance of sharpness and detail. Normally there is something of a trade-off between fine grain and increased apparent sharpness (high acutance) in developer formulae but Pyro has a reputation for giving you both. 

On the light table a strip of negatives prcessed in Pyrocat HD (top) and a strip processed in a more conventional developer (bottom). The brownish cast in the top example is the Pyro stain. There are many different Pyro developer formulations which may give more or less stain with colour casts that can range from yellowish to brownish to greenish.  

This is the theory at least, and there are other claimed advantages as well. There are those who speak of Pyro developers as though they posses near magical qualities, but still others claim it isn't worth the bother. Next to Sodium Hydroxide (Lye) it is potentially the most hazardous substance you'll encounter in photo chemistry, a powerful skin irritant and toxic if you breathe in airborne powder. (Luckily it's not that powdery but precautions are still in order.) There are a few other considerations related to keeping it chemically stable, but so long as these are kept in mind and you are willing to mix separate solutions that are only combined just before use, something I do with more conventional developers anyway, using Pyro developers isn't really much more involved that what I was already doing.

Still, when it was becoming clear that my default mode of photography had returned to something involving developing film in the kitchen sink I told myself I wasn't going to do anything crazy like get back into Pyro developers. I had HC-110, a fine developer, economical to use and with one shot liquid convenience. By the time the bottle started to run dry though I had a hankering to try something that favoured sharpness over fine grain and decided to try Beutler's formula. Though not commercially available it was simple to mix from just a few ingredients, a sort of undertaking I was no stranger to, and I've been happy using it since. 

That was until there was x-ray film to think about, that marvelous stuff that lets me shoot 8x10 for a per-frame cost that rivals 35mm. Finicky stuff it is though with its double sided emulsion that's more prone to scratching that a wax cylinder phonograph. This shortcoming can be diminished by, as it turns out, Pyro developers that in addition to their staining characteristics also tan and harden the gelatin base of the emulsion making it tougher an more scratch resistant. And if I was going to be getting this stuff to use with x-ray film anyway, wouldn't it simplify things to start using it for my regular work as well? 

And so it was that with my last regular order of supplies was a box from Photographer's Formulary containing all the ingredients needed to make a small batch of Pyrocat HD whcih is probably the most popular Pyro developer formula out there at the moment. I still haven't found the 8x10 tanks I'm looking for to properly develop x-ray negatives but no reason not to start right in the next time I had roll film to develop. A recent optometrists appointment that brought me further down the South Coast (as the Canadian side of the Lake Erie shore is referred to by we locals, or at least our tourist boards) than my usual relaxed photographic sojourns usually go gave me just that chance when I was able to roll in a side trip to the lighthouse that stands at the mouth of the Grand River.

A straight scan from the first two rolls developed in Pyro and a crop from a very small section of the image unsharpened and straight from the scanner. In the crop grain seems all but invisible though I'm wondering whether reducing agitation might have boosted apparent sharpness, which doesn't seem as apparent as I'd hoped here.

For processing information I struck out at the Massive Dev Chart site. They had no information at all for Pyrocat HD with the Fuji Acros I had, but after digging through a few forums I came up with a time of 19 minutes at 20^oC with 1:1:100 dilution. As the comparison photo of the negatives on the light box shows this was too much. They're still workable though as the top photo (from the leftmost Pyro negative), possibly in part due to Acros's ability to hold highlight detail. Superficially the middle Pyro neg looks about right but this is because I used the 10 stop ND filter that I'm beginning to realize is denser than its nominal rating and consequently the shot is really underexposed and over developed. I shot at box speed which seems about right but I will have to give it less time and possibly less agitation next time. Pyro developers reputedly require less agitation to maintain even development and reducing agitation, for reasons I hope to discuss in a future episode, increases the apparent sharpness even more. This is my hope anyway as this is one area in which it doesn't seem that results met my expectations. More experimentation is sure to follow. As always I'll keep you posted.