I'm looking for development advice.
Suggestions?
Context
I am about to take some Rollei Infrared "400" (==Aviphot 200) with on vacation, and made some tests beforehand. I found this post
That's about a 30x enlargement from 35 mm, ie a print about 4 feet wide. Since my pile of silver gelatin prints has become rather large I am storing pics on Flickr Pro. The downside to that is you cannot stop others also blowing them up to excessive dimensions. I have not ascertained if what you...
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interesting (among other interesting suggestions in the same long thread) because it showed actual pictures with vegetation, sky, and clouds...
So I made myself some metaborate, then some Barry Thorton 2-Bath developer, and exposed some '645' frames 2 days ago. As I was about to proceed with developing, I noticed nice cumulus in the sky that had been blue for days (remember Aviator, when Howard Hughes is desperately waiting for "interesting" skies?) So I shot an extra 2 frames.
Exposures
What I label "Base" exposure was obtained by setting my Sekonic 308 to 100ISO, and measuring incident light from the sun. 125/11+ is my shorthand for 1/125s, f/11 closed down 1/2 stop (halfway to f/16)
1 |
<no filter> |
"Base" exposure |
125/11+ |
2 |
<no filter> |
Base + 1 |
60/11+ |
3 |
Orange filter Heliopan |
Base + 1 |
60/11+ |
4 |
Orange filter Heliopan |
Base + 2 |
60/8+ |
5 |
IR filter B+W 092 |
Base + 4 |
30/5.6+ |
6 |
IR filter B+W 092 |
Base + 5 |
15/5.6+ |
7 |
Orange filter Heliopan |
Base + 2 |
60/8+ |
8 |
IR filter B+W 092 |
Base + 4 |
30/5.6+ |
Note that frame #5 exposure corresponds to dialing 6 ISO on the hand-held meter. Fully equivalent to
have generally incident metered at 400 iso and added 6 stops
where the "400" is just nominal, or fictional, or Rollei marketing.
Also note that with the orange filter I increased the exposure by 1 or 2 stops, definitely not the three stops engraved on the filter rim. I had already noted that with FP4 (real panchro, but not IR) 2 stops over was often too much.
Results
The film was developed in Barry Thornton's 2 bath 4+4 mins, 20.5°C. Details see
I have been working with Thorton's Two Bath Developer (120 roll film on stainless reels) for the past couple of months. I have had excellent luck so far and am settling into an agitation pattern. I have The Edge of Darkness and have done quite a bit of "web" reading on this developer. I am...
www.photrio.com
Frame 1 <no filter> "Base" exposure
Frame 2 <no filter> Base + 1
Frame 3 Orange filter Base + 1
Frame 4 Orange filter Base + 2
Frame 5 IR B+W 092 Base + 4
Frame 6 IR B+W 092 Base + 5
Interim conclusions.
- For filterless exposure, 100 ISO, incident metering seems OK if there are no important shadow details to be preserved.
- For orange filter, +1EV is appropriate with this film
- For B+W 092 filter, +4EV (ISO 6 on hand held meter) is appropriate
- Disclaimer: Snow or beach scenes may need less exposure
Appendix : transmission curve of B+W 092, nominally 695nm cutoff