PyrocatHD FP4 Semi Stand

What is PyrocatHD

Pyrocat HD. is a semi-compensating, high-definition developer, formulated by Sandy King. The advantages of formula include greater effective film speed, shorter development times, consistent staining action, lower toxicity, and no streaking or mottling with reduced agitation.

Why Use PyrocatHD

When it comes to film developers, every photographer who develops their own film is going to have their preferred choice and that’s fine. For those who are still experimenting with what certain developers can do for them, I would certainly add PyrocatHd to your list of developers to try out.

For anyone developing in trays, PyrocatHD has a high resistance to aerial fog Pyrocat-HD is an excellent developer for tray development. Negatives developed in trays, even with long development times, will have very little general stain.

How I use PyrocatHD

All my film development is done in daylight developing tanks using the agitation method whereby I agitate the developing tank by hand at certain intervals for a specific length of time.

For roll film such as 35mm and 120, I use a Paterson System 4 tank with a plastic spiral. When developing a single roll of 120 roll film, the total amount of chemistry I use is 500ml and slightly less when developing a single roll of 35mm.

For 5×4 sheet film, I use the SP-445 daylight development tank by Stearman-Press. I personally like the SP-445 because it’s easy to load and only uses 480ml of chemistry for 5×4 sheet film.

Pre-Soak Film

There are many debates as to whether pre soaking film is required and even whether it has any benefits. I do pre soak my sheet film although I have to admit that on the occasions I have forgot, I haven’t seen any noticeable difference.

I pre-soak the film for about 3 – 5 minutes in water which is at the developing temperature (21°C) and whilst this is happening I start to prepare the working solution.

Making A Working Solution

PyrocatHD is to be used as a one shot developer and comes in 2 parts (PartA + PartB). For Semi-Stand using FP4 when using the SP-445, I use 3ml of part A and 2ml of part B. To measure the quantities accurately, I use 10ml syringes. IMPORTANT: USE different syringes for each part to prevent cross contamination.

I fill a graduate with about 50ml of water at 21°C (70°F) and then add 3ml of part A followed by 2ml of part B. I then fill the graduate up to 480ml with water which has already been brought up to 21°C. Give the mixture a stir and then it’s ready to use.

Developing Times

For semi-stand development sometimes referred to as extreme minimal agitation, I use the times which Eric Rose mentioned and with his times, I have found them to produce a good negative for scanning. I say scanning because at the time of writing this article, I do not have the facility to make darkroom enlargements greater than 6x9cm.

Pyrocathd Minimal Agitation Ilford Fp4

The above chart indicates the times I use for scenes which have a subject brightness range (SBR) of 4,5 and 6. A subject brightness range of 5 is what I consider to be a normal scene.

The blue parts indicate when I need to agitate, which I do for 20 seconds. The dark grey indicates the end of development. Note that I agitate for the first 2 minutes for all situations.

Example For A scene which has a subject brightness range of 5 stops

  • Agitate for the first 2 minutes
  • Agitate at the 10 and 18 minute mark
  • End the development at 26 minutes

Example For A scene which has a subject brightness range of 4 stops (N+1)

  • Agitate for the first 2 minutes
  • Agitate at the 12 and 22 minute mark
  • End the development at 32 minutes

Example For A scene which has a subject brightness range of 6 stops (N-1)

  • Agitate for the first 2 minutes
  • Agitate at the 8 and 15 minute mark
  • End the development at 22 minutes

For scenes which require N-2 i have been experimenting with 16 minutes development times and so far the test results have been pleasing.

More PyrocatHD Information

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top