3-5 second exposure- What's wrong?

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Delta 400, MGIV FB, Ethol LDP 1:3, Bessler 23c, Minolta 50mm 1.28 , 4 seconds @f11 and a 00 Ilford contast filter.

What's wrong ...my whites are dirty and why such a short exposure?

-- Joe Lacy (jmlacy@flash.net), April 09, 2000

Answers

How big is the print? The 23C is very bright, and 4 seconds at f/11 is about right for a full frame 5x7. Before I retired it for other reasons, I used an autotransformer (Variac) with my 23CII to cut the intensity a bit. A slightly reduced lamp output will put you at the optimum aperture of the lens (say, 2-3 stops down), and 10-15 seconds for an 8x10. Cut the output further for 5x7s. Only then will you have time to dodge and burn without being in a state of panic! If the negs are about right, put the #2 or #3 filter in place and your prints should clean up nicely. BTW, the reduced output shifts the color temperature of the bulb, but the paper grade changes by less than 1/2 a number.

-- Conrad Hoffman (choffman@rpa.net), April 09, 2000.

I'm using Delta 400 rated at 320 EI developed in Kodak XTOL with a 20% pull,printed on either Polymax Fine Art or MGIVFB developed in Dektol. Print exposures are usually in excess of 12 seconds at f11 (8X10 paper).Enlarger is an Omega B8 & 50mm f4 EL Nikkor with a #3 polymax filter in the head Perhaps the over-expose & under develop sceme can work for you as well. I too have a variac attached to my enlarger with the above technique,however, I keep the device on full at all times. By the way Delta 400 in XTOL, as above, give me some of the most easily printed negs I've ever worked with.

-- Robert Orofino (rorofino@iopener.net), April 09, 2000.

Conrad's probably on the money...

This is very dependant on your negative too. If you have 'thin' negs then the enlarger exposure time will be a fair bit different to if they are really dense.

I say this because for a 8x10 enlargement, my times can vary quite a bit depending on the type of film, and how I've expoused the negative. Maybe you should do some calibration tests on camera exposure/EI Rating/film development or get someone to eyeball your negs and see if they think they look ok.

-- Nigel Smith (nlandgl@eisa.net.au), April 09, 2000.


Thin flat negs. Go to f16-f22 and use a #3 filter. Reduce the wattage of your enlarger bulb. And find the proper film speed, developed properly for the printing paper and chemistry you are going to use. And stay away from RC paper. You shoot one roll, the negs are great and then you shoot another roll and they are too thin and flat. Do you develope your own film? You should. The chemistry that the labs use isn't always as fresh as it could be when they get around to your roll. What wattage is the light source in your 23c? Get a lower wattage bulb. I have two different wattage bulbs in my darkroom just in case I run into a customer who has goofed up their film(or a lab who has screwed up). James

-- james (james_mickelson@hotmail.com), April 09, 2000.

Multigrade papers almost always look best up around grade 3 or so. This is because they need a combination of their two emulsions to look good. I aim for 3 1/2 for all of mine.

-- E. L. (elperdido65@hotmail.com), April 10, 2000.


Short exposure, dirty whites, Hmmm....Have you put a sheet of "unexposed" paper through the developer?

-- Bill Mitchell (bmitch@home.com), April 10, 2000.

An UN Safelight. I didn't think of that. A very possible explanation. This is why this I frequent B&W World. Everyone is thinking andready to help.

-- Robert Orofino (rorofino@iopener.net), April 10, 2000.

Two points -- First, I'd be interested in knowing what kind of autotransformer would applicable to a 23c. I too sometimes have very short exposure times at f8, but my negatives are not that thin, just contrasty (pushed). Second, "dirty whites" could be a consequence of using the 00 contrast filter -- i.e. somewhat flat and unclean -- but I guess it all depends on what one means by dirty.

-- Christopher Hargens (ldmr@cruzio.com), April 20, 2000.

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