frustration with condensers

I use an Ilford anti-static cloth on the negatives, which cleans them
up really well. I favour glassless carriers. If you're using a glass
carrier, it's somehwat more difficult.

Are you talking about spots from dust on the condensers? Yes, they must
be kept clean, but at normal lens apertures any spots on the condensers
are very far out of foucs.


Mike wrote:
Any of you get frustrated with keeping spots, lines, and specs clear when
using a condenser?

I'm using an old Omega DII condenser for 4x5. The original glass wasn't
perfect. I found replacements on eBay and ended up using one piece from
each set after trial and error. However depending on the exact focus, I
still get some lines/spots that show up. Most the time this isn't a
problem unless the enlarger height and focus is at some exact spot.

It might be time for me to plop down $300 for an Aristo V54 head....

"Mike" wrote

the bottom glass is very near the negative and this is where
the focus is!

To keep the size of the condensers manageable. The light
from the condensers exits in a cone that comes to a 'focus'
on the rear element of the enlarger lens.

If the condensers were 1 inch above then they would have to be
17% larger. To get the mass of the condenser one cubes the
linear dimension: 1.17^3 = 1.6. In fact the whole lamphouse
would be 1.6x as heavy (and at a minimum 60% more expensive)
than one where the bottom condenser sits just above the negative.

The 17% comes from ratioing the present distance from the
condensers to the lens ~6 inches, by the new distance ~7".

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer: Electronics; Informatics; Photonics.
To reply, remove spaces: n o lindan at ix . netcom . com
Fstop timer - http://www.nolindan.com/da/fstop/index.htm

On Fri, 13 Jan 2006 15:44:58 GMT, Mike
wrote:

I use an Ilford anti-static cloth on the negatives, which cleans them
up really well. I favour glassless carriers. If you're using a glass
carrier, it's somehwat more difficult.


Not talking about spots on negatives


February 1, 2006, from Lloyd Erlick,

Although the discussion is about condensers
rather than negatives or carriers, I have to
remark about glass negative carriers.

For many years (many) I used glassless
carriers. My reason was the supposed ease of
operation. Laziness doesn't really even
qualify as a reason, because I had never
tried glass carriers so I could not say which
was easier or 'lazier'.

Well, after I finally slipped the glass
inserts into my negative carrier and made
some prints, I realized the prints were
better. Glass negative carriers help one make
better prints. Period. The reason is negative
flatness. The results are plainly visible in
prints; the corners are noticeably sharper
when glass a carrier is used. It saddens me
to say this, because I have years of prints
made glasses. But it is true.

It is accurate to say my reluctance to try
the glass carrier was based on laziness. I
believed the extra four surfaces would be a
nightmare of dust and specks and print
spotting.

But no nightmare ensued when I finally tried
glass. I made sure the glass inserts were
clean before I put them in. One was
anti-Newton ring glass, and both were brand
new, so pretty clean. In any case, cleaning
them was no problem, and took only a moment.
Since they are just glass, cleaning in
distilled water would be simple where
necessary. The glasses are plain flat
surfaces, so they're far easier and quicker
than cleaning a lens, at any rate, although
even that is hardly an onerous task. And like
a lens -- especially a nice house-trained
enlarger lens -- it will stay clean. Yes we
can mess it up, but how often does that
happen, even for slobs? I find cleaning the
glass carrier is extremely easy with one of
those cloths they include with a pair of
eyeglasses, and a bit of breath on the glass.
No spit, please.

So the glass negative carrier is really
extremely little more work than glassless,
but it has a definite payoff in print
improvement.

We have Bob Saloman to thank for persisting
in pushing the notion of glass negative
carriers. I read his exhortations a long time
before I tried.

regards,
--le
________________________________
Lloyd Erlick Portraits, Toronto.
voice: 416-686-0326
email:
net: www.heylloyd.com
________________________________
--