[Leica] Re: Off-subject - enlarger light source

[George Huczek <ghuczek@sk.sympatico.ca>]

At 08:45 AM 02/04/99 +0100, Gerry(UK) wrote:
>  Can someone please give me
>advise on the relative merits of this type of head?   BTW, I already have
>the necessary filtration for use below the lens if necessary, so will have
>no need to purchase the filters but have had some difficulty attaching them
>to my existing enlarger.
>
Yes, you will likely get quite a bit of advice on this topic.  I use both
of the types of heads you described, so I can give you some observations
from personal experience.
   First, you should note that the contrast that you are aiming for during
print development should be matched to the type of light source you are
using.  With a condenser enlarger head you should develop your negatives to
normal contrast and with a diffusion head you should aim for higher
contrast to get the best results, because the diffusion head will tend to
lower print contrast slightly.  You can compensate for the contrast
differences slightly by changing paper grades in B&W, but film development
will have a marked effect on the tonal range obtainable from the print.
So, you can not exactly match a print made with a condenser head to a print
from the same negative made on a diffusion head just by changing paper
grades.  There will be noticeable differences in the way shadow and
highlight details are rendered using each enlarger source.  This applies to
sliver-based films; chromogenic film is more tolerant of changes in the
type of light source used.
   Condenser heads will produce a grainier-looking image.  Personally, I
like this look very much, especially when using Rodinal developer.  For the
right type of image, prints look sharp, rugged and masculine.  (For
portraits, especially of women, a diffusion enlarger head is usually nicer,
to soften the image slightly.)
   A condenser head will also show any defects in the negative very
clearly.  Dust and scratches will show up and require a great deal of
retouching.
   Finally, regarding the filtration issue which you raised, you may have
to do some testing to match the filtration of your VC filters with what you
are accustomed to getting from your dichroic head.  This will take some
time, but is necessary if you want to do it right.  
   I would also add that you should try to place your filters above the
lens rather than below it.  I use VC filters above the lens most of the
time, but I do use them below the lens as well.  When I need to print with
split grades using a condenser head, I find that it is more likely to
disturb things if I try to open the filter drawer to change filters between
exposures.  Instead, I lay the filters below the lens on a filter mount,
and nothing gets disturbed when filtration is changed.  I handle my filters
with gloves, so they stay clean -- this lets me get away with using them
below the lens with no appreciable loss of image quality.


 _
[o] -GH