What are typical print exposure times?

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I have an Omega D2V condenser enlarger. When making 8x10 prints from 35mm negatives (using an 80mm lens) I'm getting exposure times between 2 and 4 minutes. Is this "typical" for this setup? When I used an old B66 enlarger the times were much quicker (under 1 minute). What kind of exposure times do you typically see? I also noticed that the bottom flat surface of the lowermost condenser seems to be frosted. Is this normal? Could that be causing my long exposure times?

-- Bill Akstens (bill.akstens@trw.com), April 25, 2001

Answers

You should see 10-20 second exposure times depending on the head to print height. The bottom condenser should not be frosted. I think the frosted diffuser has been left in place.

If you haven't taken a condenser apart, carefully remove the condenser assembly and take it to a flat soft surface. A bed is ideal. Invert the assembly slowly and remove the top condenser, corrugated separator and bottom condenser. The Opal glass should then come out. If dirty, clean the condensers with window cleaner and carefully reassemble. These things are reasonably tough but can be chipped or cracked easily and they are not cheap to replace.

Bon chance!

Duane

-- Duane K (dkucheran@creo.com), April 25, 2001.


I've never seen an opal glass installed under the condensers as a standard thing. Certainly it would convert the machine from condenser to diffusion, which might be good. With the condenser set for 35mm, my D3 exposes an 8x10 piece of Seagull or Multigrade IV in about 8 seconds at f/5.6- if it takes you 2-4 minutes, I'm amazed that you can even see the image to focus it! The only way I could get that long an exposure is to put the paper in upside down. Try removing the opal glass (hopefully sombody didn't frost the actual surface of the condenser) and also check to see what wattage bulb is in place. In the "really obscure" catagory, check that someone didn't install a diode and switch in the line cord to provide two intensity settings- rare, but it has been published as a darkroom tip/trick many years ago.

-- Conrad Hoffman (choffman@rpa.net), April 25, 2001.

If your enlarger is aligned, you should have no problem printing at f8 or f11 and your printing times should be 10-30 seconds. I say this about the enlarger because if the negative stage is off axis your prints won't be sharp at some level. Also, check to make sure you have the right bulb in your D2. Cheers

-- Scott Walton (f64sw@hotmail.com), April 26, 2001.

What size light bulb is in the enlarger? That's another thing you could check that could contribute to extended exposure times.

-- Joe Lipka (JoeLipka@compuserve.com), April 26, 2001.

What aperture are you using? If you are getting 4 minutes at f22, that equates to 30 seconds at f8, which is not outragous. You may a low wattage bulb installed in the D2.

-- Ed Farmer (photography2k@hotmail.com), April 26, 2001.


Last night I disassembled the condensor head. It turns out the previous owner had installed a piece of milk plexiglas below the lower condensor. It reduces the light output, hence the long print times. I will have to study the benefits of shorter print times vs more diffuse light. Thanks for all your comments and help!

-- Bill Akstens (bill.akstens@trw.com), April 27, 2001.

You found the reason for your long printing times. If you have been using various papers you might find the same long times as well even with straight condensers. Some papers are slower than others and a few are positively glacial.

-- Dan Smith (shooter@brigham.net), April 29, 2001.

your piece of milk plexiglass must have been practically opaque to give you four minute exposures. With regard to short times versus diffusion, I'm not so sure that the old arguments of diffuser versus condenser still hold true. The thought with condensers was that whilst they gave higher contrast (this is still the case), highlights were also poorly separated due to the Callier Effect. The Callier Effect was a problem with the older thicker emulsions but modern films do not suffer to anything like the same degree. However diffusers do have one great benefit and that is they hide dust. Ok if you empty your vaccum cleaner over your negs you will get spotty prints but I have found I have to do a lot less retouching with a diffusion head. I converted my enlarger (a very well made Opemus 6 Super 6) to a multigrade head which is a diffuser head. My exposure times were actually shorter due to having a halogen bulb in the head. Contrast was unaffected to and there was certainly no loss of sharpness. The the three big benefits were a) Dial in grade filtration with the possiblity of accurately dialling in one quarter grades, b) up to two stops dial in neutral density for those tricky dodging and burning in exercises and c) a lot less retouching.

Adrian Twiss

-- Adrian Twiss (avtwiss@ukonline.co.uk), April 30, 2001.


Hi Bill,

since you are using an 80 mm lens you are using less than half of the light passing through the lens (with 35 mm negatives). If you get yourself a (preferably modern) 45-50 mm lens (optimal for 35 mm)you will cut the exposure time to less than half. You will also get sharper, contrastier prints. 80 mm lenses are optimized for medium format negatives.

-- Peter Olsson (peter.olsson@lulebo.se), May 04, 2001.


Let me correct myself for my answer above. I assumed that you were using the 80 mm lens together with condenser-lenses matched to that lens. Changing lens will not help with the exposure time unless the condensers are changed to a set optimized for the shorter focal length.

So, a 50 mm lens with matching condensers (or diffusionbox) will give you shorter exposure times than an 80 mm lens with m-ing condensers!

-- Peter Olsson (peter.olsson@lulebo.se), May 08, 2001.



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