Re: Double vs Single Condenser Lens

On Apr 13, 4:55 pm, news*NOSP...@xxxxxxxxxxxxxxxxxxxxxxxxxxx (A R)
wrote:
I've started taking 6x6 photos. Instead of buying a new enlarger, I'm
adapting my trustworthy MPP condenser to take 6x6 negs. This has
involved fabricating a new lens board, fabricating a new neg holder,
purchasing a new enlarging lens and replacing the condenser.

Now, I have a pair of spherical condenser lenses but unfortunately I
have no cell to mount them in. A single lens on its own fits snuggly in
the enlarger head and seems (by eyeball) to give a uniform illumination
across the easel.

I know some enlargers use single apsherical lenses but what
advantage/disadvantage do I have using a single spherical lens?

Come to think of it, I'm not to sure why condenser lenses come in pairs!

--

I need more time!

Broadly, I think the objective of a condenser system is to (i) as you
said evenly illuminate the negative, (ii) pass as much of the light
through the negative as is practical and (iii) pass it through as
nearly colimated as possible.

With one lens, if the convex side is toward the negative, objective
(i) would likely be fulfilled. I have doubts about (ii) and (iii).
.

Relevant Pages

  • Re: Double vs Single Condenser Lens
    ... involved fabricating a new lens board, fabricating a new neg holder, ... purchasing a new enlarging lens and replacing the condenser. ...
    (rec.photo.darkroom)
  • Re: Photomicrography ... objective questions (and general advice)
    ... E200-F only supports Koehler illumination with its Abbe condenser. ... uses a quirky relay lens to make Koeher illumination work. ... Don't buy a new scope if you budget is below US$3000. ...
    (sci.techniques.microscopy)
  • Double vs Single Condenser Lens
    ... Instead of buying a new enlarger, ... involved fabricating a new lens board, fabricating a new neg holder, ... purchasing a new enlarging lens and replacing the condenser. ...
    (rec.photo.darkroom)
  • Re: B& L Dynazoom question
    ... I'm pretty sure you have the older gray color Dynazoom. ... elements of the condenser were screwed into the stage and a thrid ... convex lens was mounted on a rack. ... >Under that is a lens, diaphragm, and slide-in holder assembly that is ...
    (sci.techniques.microscopy)
  • Re: Double vs Single Condenser Lens
    ... purchasing a new enlarging lens and replacing the condenser. ... The symmetry does not correct spherical aberration but the plano-convex shape of the condenser reduces it. ... Some enlargers use only a single condenser but, since most condenser enlargers also use light sourses of relatively large area and diffuse surface the aberrations of the condenser have less effect. ...
    (rec.photo.darkroom)