Reciprocity failure...

[Jehu]

When my camera outfit was stolen in January, I lost the only copy of my chart of reciprocity failure. I had it on a computer but the hard drive crashed on that one. I normally store ALL of my documents on a server drive but I broke the rule on that one. Don't ask me why. Anyway, I've been trying to reassemble my chart from scratch. The last chart I had was mostly assembled from manufacturer's tech sheets. I'm trying to do that again but those only go up to a couple of minutes at the most.

Is anyone willing to share their reciprocity failure charts? I'd rather not go through the long (and somewhat expensive) routine of testing my films again.

edit:
I use mostly Delta 100, Portra 160VC, Portra 160NC & VS100

[Vlad Soare]

The attached charts work for me, though unfortunately none of the films you use is included. I only have Fomapan 100, TMY-2 and HP5+.
The first column is the metered exposure. The second, in bold font, is the corrected one.

[Gary Tarbert]

When my camera outfit was stolen in January, I lost the only copy of my chart of reciprocity failure. I had it on a computer but the hard drive crashed on that one. I normally store ALL of my documents on a server drive but I broke the rule on that one. Don't ask me why. Anyway, I've been trying to reassemble my chart from scratch. The last chart I had was mostly assembled from manufacturer's tech sheets. I'm trying to do that again but those only go up to a couple of minutes at the most.

Is anyone willing to share their reciprocity failure charts? I'd rather not go through the long (and somewhat expensive) routine of testing my films again.

edit:
I use mostly Delta 100, Portra 160VC, Portra 160NC & VS100

If you push the boundarys of reciprocity often have you thought about Fuji Acros ??best on market Why use 400?? Cheers Gary

[Jehu]

Thanks for the advice Gary. When I started LF about 3 years ago, I resolved to make changes slowly. I wanted to spend enough time with a particular film/developer combination to be able to understand changes as I make them. I still haven't delved into the world of Fuji but I suppose I will sooner or later if it's a readily available film.

[Leigh]

I still haven't delved into the world of Fuji but I suppose I will sooner or later if it's a readily available film.

I would strongly recommend you try Fuji Acros. It's readily available in 4x5 and smaller sizes.

It's probably the world champ for reciprocity characteristics... NO correction at all for exposures up to 120 seconds (2 minutes), and only 1/2 stop increase for exposures from 120 to 1000 seconds (almost 17 minutes).

It's only available in 100 speed. Fuji Neopan 400 is a completely different film.

- Leigh

nb - One point that caused some confusion earlier this year was that Fuji discontinued the 10-sheet 4x5 packaging, replacing it with a 20-sheet package. Some people interpreted this to mean that Acros was discontinued in 4x5 size, which is untrue.

[cjbroadbent]

My chart: f64 and go out to lunch, f45 and go for coffee.
After 15 minutes, an hour or so makes little difference and what difference there is quite acceptable.

[dsim]

My chart: f64 and go out to lunch, f45 and go for coffee.
After 15 minutes, an hour or so makes little difference and what difference there is quite acceptable.

Brilliant.....

[Heroique]

...those only go up to a couple of minutes at the most.

Here’s a quick chart for anybody else who mostly stays under 2 minutes...

Or you might call it a “starter’s chart” for traditional b/w films (not T-grain), until one becomes more familiar w/ personal equipment, film processing habits (such as “N-1” or “N-2”), and preferred results. As you learn more, adjust to your taste:

• Metered 2 sec. – use 4 sec (2x)
• 4 sec – use 12 sec (3x)
• 8 sec – use 32 sec (4x)
• 15 sec – use 75 sec (5x)
• 30 sec – use 3 min (6x)
• 60 sec – use 7 min (7x)
• 120 sec – use 16 min (8x)

(Note how easy this is: No correction until 2 sec., then each additional stop increases the multiplier by one.)

Over time, my personal reciprocity charts have started looking very different than manufacturing suggestions.

They also look different than the “starter’s chart” above.

[Eric Woodbury]

Here's the Howard Bond article from our friends at Photo Techniques

http://www.phototechmag.com/index.ph...e/reciprocity/

[Vlad Soare]

See also Patrick Gainer's article here. It explains how you can build a reciprocity failure chart for any film, starting from just one known point.