Astrum · ISO 100 B&W negative
Astrum Foto 100
Astrum Foto 100 is one of the more honest pieces of fiction in the current B&W market. It sells as a Ukrainian-made stock from the old Svema lineage, with the right blue-and-yellow packaging and the right backstory. The reality is more complicated. Comparative testing by working photographers has lined up Astrum Foto 100 almost exactly with Agfa Aviphot Pan 200 cut to a slower rating, and the consensus on Photrio and EMULSIVE is that Astrum is now mostly a re-spooling operation rather than a production line.
That origin is not a problem. Aviphot Pan is a respectable aerial-survey emulsion with fine grain, high resolution, and a slightly extended red sensitivity that gives the film some near-IR character with a deep red filter. The polyester base is the thin, hard, mylar-style material you get on most repurposed aerial stocks. Great for flatness in the negative carrier, awkward in some plastic-spool 120 backs.
In practical use the film behaves like a contrasty ISO 100 pan stock. Box speed works in flat light; rate it at 80 in harsh midday sun for more shadow. D-76 1:1 around eight minutes is a safe start. Rodinal 1:50 sharpens the grain and is the go-to if you are after the older European look. Compared with Fomapan 100, Foto 100 is cleaner in the midtones and less prone to base fog, but it lacks the warmth that makes Foma feel mid-century.
One quirk: the anti-halation backing comes off in a slightly alarming purple wash during the first water rinse. That is normal, not bad processing. An extra minute of running water clears it.
The brief lists Foto 100 as discontinued. Astrum's production cadence is batchy enough that any given shop might or might not have stock, but Freestyle and several European retailers were still listing it in 2025. Buy when you see it.
Reciprocity exponent is 1.31. Zone Light Meter applies the correction past one second. A 30-second metered exposure becomes about 90 seconds at the negative. The Aviphot base handles long exposures more gracefully than the listed exponent suggests.
How the app handles this stock
- Box speed: ISO 100. Picker exposes pull/push chips so you can shoot it at any speed you want and the meter follows.
- Reciprocity: Above one second the app raises metered time to the power of 1.31.
- Expired film: if you load an old roll, set the expiry year and storage in the app and the ISO scales for you. B&W negative decay rates are baked in.