Film Development
DiaFine ISO Test
Diafine ISO Test With FomaPan 200 35mm Film
What Is Diafine
Diafine is a 2 bath fine grain, full or greater film speed two-part black and white developer that possesses some pretty incredible characteristics that you may want to be aware of if you are not already.
It is simple, extremely tolerant of temperate ranges during development and produces excellent results when paired with certain films.
Diafine can be used over a wide temperature range with one developing time for all films. Fast, medium and slow films can be developed simultaneously without adjustment in developing time.
Diafine is said to produce the greatest effective film speed, ultra-fine grain, maximum acutance and highest resolution.
Time and temperature have no practical effect if the minimum recommendations are observed.
The Diafine information sheet is available from this link
My Diafine ISO Test
For this test I chose to use FomaPan 200 35mm black and white film.
The purpose of the test was to photograph an X-Rite Color Checker at different ISO ratings and then see how they looked after developing them with my normal process.
Camera: Pentax Spotmatix SP1000
Lens: SMC Takumar 55mm f/2.0
Subject: X-Rite Color Checker Passport
How I Made The Test
I took a spot meter reading of a Kodak Grey Card which gave me 1/4 second at f/8 ISO 100 which was to be my first exposure. I then changed the exposure by one full stop until I had reached the equivalent of ISO 3200.
The X-Rite Color Checker below shows the colours of the patches which can be used as a rough indication to compare the grey tones of the film scan at different ISO values.
How I Use Diafine
I put both bottles A and B into a water bath and bring the temperature up to 20 degrees centigrade.
Part A (Developer)
- Pour A into the development tank
- Agitate slowly for 30 seconds
- 2 inversions at 2 minutes and 4 minutes
- Total time 5 minutes
- Pour A back into its bottle for next time
Part B (Accelerator)
- Pour B into the development tank
- Agitate slowly for 5 seconds
- 2 inversions at 2 minutes and 4 minutes
- Total time 5 minutes
- Pour B back into its bottle for next time
Water stop bath, fix and wash as normal.