Age of enlarger lamp affecting exposure time

greenspun.com : LUSENET : B&W Photo - Printing & Finishing : One Thread

I have an old Omega B66 which I bought used a few years ago. I realise enlarger lamp intensity gradually decreases with age, which of course affects exposure time. A lamp, I am told, may last 3 years, for week end users. Does this mean that if I want to reprint something I did one or two years ago, I need to start all over again. That all the notes I took the last time around is basically useless.

-- Mei Leng Lau (bohl-lau@ erols.com), November 20, 1998

Answers

Mei Leng, not only does lamp age contribute variation to the process but so will small differences amoung lots of paper or batches of developer. So it is unlikely that a year or two down the road you could make a near identical print on the first try. You may not be able to do that even a short time later. Still, your notes are hardly useless. The decisions you made about contrast, dodging and burning, and yes, even exposure time, will certainly help you achive a finished print much faster than if you didn't have that information. Wouldn't you agree? To Ansel Adams the negative was like a musical score and each print had the potential to be a different performance of that score.

-- mitch rosen (mitchrosen@sprintmail.com), November 21, 1998.

Mei;

Keep your darkroom notes on print making in terms of %, +10%, -30%, etc. Over time, when you go back to make a print, one you have established the basic over all exposure, then the burning, dodging, can easily be recalculated. There are a lot of other things That can change in your darkroom over time, such as develper freshness, different developers, changes in the paper manufacture, a new enlarging lens, etc, etc.

Also, if you keep these type of notes, I've found it a good idea to have a master print that you retain in your files. When reprinting, you will have an orginal to shoot for, and you will know when you are on the money. Or you may decide to do it quite differently!?!

-- Gene Crumpler (nikonguy@emji.net), November 22, 1998.


Mei, I have also noticed that enlarger bulbs made by different manufacturers have different intensities. This will throw your times off horribly, as it did mine!

-- Regina Hugo (vhugo@earthlink.net), December 24, 1998.

Moderation questions? read the FAQ