How to save underexposed Tri-x

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Hi all, I've under exposed by one to two stops. And I'm wondering how to save the image. I'd like to get as much detail from the negative as possible, but what I really don't want is a grainy photograph. It's 4X5 Tri-x 320. The balance of the compromise has to be infavor of "no grain." Maybe I should just develop 25% more and then stain with something, this will give me contrast and image, but I'm affraid this will give too much grain, and I've never really used any stains to cover grain before so I don't know how well it would work. I want to enlarge to 8X10. Or maybe I could go from 4x5 up to 8x10 negative? Any ideas before I try and develop this. Thanks.

-- david clark (doclark@yorku.ca), October 08, 2000

Answers

Response to Underexposed film???

Process in PMK Pyro. You will pick up highlight density, have shadow detail and all in all have a very printable negative. 1-2 stops underexposure is not all that much when you are using PMK Pyro. With other developers you will get contrasty, grainy negs if you overdevelop.

I would shoot a few additional sheets of film and intentionally underexpose 2 stops as well. Then process each sheet +10% +20% +30% and +40%. Check the result and use the appropriate time for your underexposed and valuable negatives.

-- Bill Smithe (bs2@aol.com), October 08, 2000.


Response to Underexposed film???

You are worrying too much about the grain. You are only enlarging 2 times, 4x5 to 8x10. You could use the old Kodak Recording film and not worry about grain in such a small enlargement. Take the advice to shoot similarly exposed film and test process it, but you are worrying too much over this one.

-- Dan Smith (shooter@brigham.net), October 08, 2000.

Response to Underexposed film???

I agree with Dan...grain shouldn't be a problem with an 8x10 enlargment. Try a test with additional development and see how it looks. You can also gain about a stop of exposure by selenium toning the negative. If you have seriously underexposed the film and there wasn't enough light to break the threshold in the shadows, no amount of development will salvage the shadows.

Hope it works out o.k.

-- Doug Paramore (dougmary@alanet.com), October 08, 2000.


I would process in a developer like FG-7, 1:15 in a 9% dilution of Sodium Sulfite--go to the Falcon Home page and scroll to the data for FG-7. Then if the neg still is a problem try selenium toner, 1:1 in hyp neutralizing agent for up to 10 minutes plus another wash. Between the two you should be able to rescue the negative easily. FG-7 in sodium sulfite will reduce grain structure , provide added speed and reduce your development time. It is not the silver bullet of developers, but for the situation you face it may be worth a shot. Alternative: Process films for N+1 in the developer you normally use and then use selenium toner. If you use Pyro, this probably will not work, but D-76, TMaxRS, acufine, etc.etc. plus selenium would help. Finally, there is always photoshop! Bob

-- Bob Moulton (bobmargaretm@home.com), October 09, 2000.

Diafine is supposed to give you at least a 1 stop gain, perhaps 2.

TMax RS and other phenidone based developers are also supposed to give some speed gain.

I especially like the other reply that suggested intentionally underexposing and checking out the results.

-- Charlie Strack (charlie_strack@sti.com), October 10, 2000.



Would there be any advantage to post-exposure - adding a little exposure to the whole negative to pump up the low values a bit?

If you're doing experiements, you might want to try that.

-- John H. Henderson (jhende03@harris.com), October 11, 2000.


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