Infrared is making me crazy?

The sfx is not the best film for infrared, i dont now if the kodak infrared film in your place is afelebel.Normaliy the sfx must by defelept whit d 76 or id 11 from ilfort whit a time of 10 min. whit the stock solution .
Ludo.

Because it isn't true IR, SFX shouldn't suffer the same kind of shortlife problems as other genuine IR films or at least nothing to the same extent.

Is the IR filter you've got the right one for SFX as it doesn't go that far into the IR range?I haven't seen anyone report this kind of problem with the correct filter. I was given two rolls of SFX from a person I bought my darkroom stuff from so I am pretty sure it was quite old and while I have only ever used a red 25 filter with it I didn't have this problem.

I'd start a thread on this if I were you for a range of advice

pentaxuser

I expose SFX as ISO12 with the SFX filter, and develop in DDx. No problems to date. Usually SFX can be exposed at ISO200 and developed normally I believe to produce a pretty normal B&W film. K

Hmm... Overdevelopment should not yield black negs - that sounds more like gross overexposure. It looks like your posted photo was taken in full sun. If your ideal film speed for SFX with filter happens to be 25, then by definition full sun would call for 1/25 at f/16. Then at f/22, your speed would be 1/12th. If you are in fact shooting at 1 second at f/22, then you are overexposing by around 3.5 stops. This could definitely give you black negs. If your TLR shutter is sluggish (as so many are), then the overexposure is even greater. If your test negs without filter were OK, but the actual negs with filter were too dense, then I would recommend a close inspection of every square millimeter of the Infrarot, especially around the edges. They can degrade over time. However, based on the excessive density of both test and actual negs, I would throttle back on exposure. (Incidentally, when you expose the test shots at ISO 200 and 400, what actual aperture and speed are you using?)

Good luck,
Jon

PS: When you say 'Test shot is always black from overdevelopment times' I am taking this to mean the negs are black. Is this correct?

Your feedback helped.

I was able to determine the problem with the ilford film---I was convinced I was processing it incorrectly. It was my TLR from 1932 that was the problem. Close inspection revealed the shutter was not allowing the blades to shut completley. IE F16 would leave a F22 opening after exposure and F22 leaving an F64? opening after exposure...almost effectively solarorizing my infrared film. It is a new problem that started with when I put my first roll of rollei(9 rolls ago) embarassing!! and I chaulked it up as learning curve rather than equipment failure