Enlarger exposure times / f stop settings

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Can someone tell me where I am going wrong. I am printing black and white 6x6 with a converted Beseler Printmaker 35 (two 4" condensers) I cannot seem to get any exposure time and or open lense settings. Everything is around 10 to 15 sec's at f22. I am using Adorama Multigrade RC paper and Ilford filters. Contrast changes according to filter change, but exposure time seems short to me. Thanks

-- Charlie Griffin (griffcme@aol.com), February 28, 2001

Answers

Seems to me you need a ND filter perhaps a two or three stop, heck maybe more. Applying the ilford filters will create some ND effect but not enough. By applying the two stop ND filter it will get you back to using the sharper aperatures of the enlarging lens,f11 at 10- 15sec.

-- John Kufrovich (jkufrovich@ev1.net), February 28, 2001.

This is a pretty common problem. Ideally you want to use the lens at its optimum aperture, 1 or 2 stops down from wide open. You also want enough exposure time so you can dodge and burn. I like about 10 seconds. ND filters will get you there. You can also look for a lower wattage bulb, though often that's not an option. I have my enlarger plugged into a variable transformer (Variac or similar) so I can dial up whatever voltage and intensity I want. You can dim the bulb substantially before there's enough color shift to affect VC paper. Cheap light dimmers are tempting, but they can suddenly change intensity due to line noise. You might try one, then get an autotransformer if you like what the light dimmer does.

-- Conrad Hoffman (choffman@rpa.net), February 28, 2001.

Charlie, I may be reading this wrong but 10-15 seconds isn't really a short printing time. You should be able to effectively do all the burning and dodging with this length of time but if you do need more, I would go with a less wattage rather than an ND filter (just one more surface you have to worry about keeping clean). I usually like to be in the 3-8 second range myself but I print cold light. Cheers, Scott

-- Scott Walton (f64sw@hotmail.com), March 01, 2001.

Charlie,

I would check your negative density. Unless you're making your negatives intentionally thin, this seems a bit extreme to only be able to print at f22. I've had negatives at varying densities for years, and never have had one so thin that I could only print on f22. Don't know if this helps any...

Jon Osing

-- Jon Osin (josing@bcr.com), March 01, 2001.


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