which lamp for variable contrast paper

[vicmortelmans]

Hi,

my darkroom setup is based on a very old and basic b&w enlarger, which, when I obtained it, had no lens, no lamp, no negative carrier and no filter holder.

I mounted an M42 Takumar on it, made myself a (kind of) negative carrier and I can also put the Ilford variable contrast filters below the lens.

Now I'm a bit puzzled about the lamp. I bought a powerfull halogen lamp in the nearest store. It allows to stop down to 5.6 ~ 8 and have exposure times of ~8 seconds (for 13x18cm prints), so the power is OK.

Yet, I noticed that the contrast of normal paper (grade 3) is higher than variable contrast paper with the grade 3 filter on. Is this normal? Or is my lamp not suited for this configuration and maybe adding a color cast?

Are (b&w) enlarger lenses any special? Which kind of fittings do they come in (my enlarger has the same fitting as normal home armatures).

Groeten,
Vic

 

[bsdunek]

Most older enlargers used the PH series of lamps. These were:
PH211 - 75W
PH212 - 150W
PH213 - 250W
In my Durst 606, I use the PH212, while in my Knidermann 6X9 enlarger I use a PH213. I would start with the PH212 and see how it works.
As for enlarging lenses - they are different than camera lenses. They are designed for a really flat field, as both your negative and paper are flat. Generally a camera lens has a curved field as you are taking photos of a three dimensional world.
That said, for years I used a Scheinder 75mm f4.5 lens salvaged from an old Voightlandr camera for my 6X6 work and it worked pretty good stopped down. Opened up, I could either get sharp center or sharp corners, but not both.
Enlarging lenses are pretty cheap now, so it would be worth picking one up.