Rating Adox/efke 100

[Matthew Rolfe]

I've just run a full film speed test for Adox/efke 100 (8x10) - making a series of Zone I exposures to find the film speed that gives the correct density for Zone I....

I developed in Rodinal 1:50 and using my densitometer came to the conclusion that the correct density for Zone I occured when the film was rated at 50 ISO.

There are so many opinions on how to handle Adox films, I have read in several places that the films shouldn't be overexposed and that they should instead be underexposed for optimum results. I have also read that 80 ISO as well as 200 ISO are good ratings for the 100. I can understand that many people rate differently due to personal taste, but what confuses me about the Adox films is that there are so many different opinions on simply getting 'optimum results' and how varied they all are. It seems that half of what I have read advises rating slower and the other half rating faster.

Any feedback would be greatly appreciated.

Matthew

[ic-racer]

You have done a good job cutting through any confusion. Use 50 as your test indicates. :)

[Mark Sampson]

Matthew- trust your tests and don't worry about what other people say.
Your challenge now is to find the development time that gives you beautiful highlights- no great task. Then you can go make photographs and not worry.

[Eric Rose]

My tests and experience show the rating to be at 50 asa as well.

[renes]

Did someone make similar test with Adox 50 ISO (4x5, 120)?

What was your rating?

[Wallace_Billingham]

FWIW I have never understood the advice not to over expose Efke films. They handle over exposure far better than under and I usually rate them a full stop below box speed

[renes]

FWIW I have never understood the advice not to over expose Efke films. They handle over exposure far better than under and I usually rate them a full stop below box speed

Did you do it with Adox 50 too (expose it as 25 iso)? Or you found better result with 32 iso?

[Wallace_Billingham]

Did you do it with Adox 50 too (expose it as 25 iso)? Or you found better result with 32 iso?

I would rate it at 25 unless the light is very contrasty in which case I would go with 32.

To be honest with you however most of my experience with Efke 50 is doing very long exposures well into the minutes using ND filters. A few years back I tested a run of Efke 50 with the metered scene one the filter factor and reciprocity on the box was figured in at 5 minutes using an iso of 50. (It was a cloudy day, I used a high f/stop and a 10 stop ND filter)

I did shots for 2.5, 5, 10, 20, and 40 minutes. The 2.5 minute exposure was nearly blank and the 5, 10, and 20 minute were all very usable with the 10 minute one being the best. The 20 minute one was still pretty decent but the highlights were a bit dense. The 5 minute exposure was a bit on the thin side but still very much scanable or printable, and the 40 minute one was pretty dense but could be scanned or printed if needed but with a bit of work.

I have shot a few rolls of the Efke 50 in 120 roll film in an old Minolta Autocord TLR and rate it at 25 and they looked pretty nice.

Most of my experience with the Efke films is the 100 and the IR820 which I always rate 1 stop slower than box speed.

I should be noted that when doing the above I use Rodinal and/or Diafine as my developer(s) of choice. Unlike with some films I don't think that Diafine gives much if any push with the Efke films and if does being a 2 part developer you should err on the side of overexposre anyway

[renes]

Thanks.