Enlarging lens for 6x7

[Herminus]

I just got a Fujinon 90mm ES f4,5 for my Magnifax 4. (69USD on ebay).

To my surprice 6x7 vignettes badly at the long ends (the film holder is 6x8,5m).

What lens would be good for 6x7 with 39mm threads?

 

[ic-racer]

Why do you think the issue is with the lens?

 

[Rick A]

I just got a Fujinon 90mm ES f4,5 for my Magnifax 4. (69USD on ebay).

To my surprice 6x7 vignettes badly at the long ends (the film holder is 6x8,5m).

What lens would be good for 6x7 with 39mm threads?

I'm not familiar with your enlarger, but my guess would be that the condensers are not in the proper position for the format.Does your machine have adjustable condensers?
If you are indeed trying to enlarge 6x9, then the 90mm will not cover and you will experience vignetting. You will need a 105mm lens for that format, or a Wollensak 90mm Enlarging Raptar, it's designed to cover 6x9, but uses a 29mm mount not 39mm.

 

[Ian Grant]

I would expect a 90mm enlarger lens to cover 6x7, it's a Tessar type though so not as good coverage as their more expensive range.

As above it's more likely an enlarger issue. Fuji sold 75mm lenses for 6x6, 90mm for 6x7, and 105mm for 6x9 this is common to most manufacturers five or take 5mm.

Ian

 

[Steve Goldstein]

Are you seeing vignetting wide open or with the lens closed down a couple of stops? I agree with Rick here, most likely it's not the lens.

In general the "standard" focal length for 6x7 is 90mm, though there are some exceptions. For example, the 80mm Nikkor-EL and the Rodenstock 80mm Apo-Rodagon-N are both specified as covering 6x7. The rare 90mm Apo-Rodagon (non-N) is said to vignette (I have no experience with that one) but the even rarer 90mm Apo-Rodagon-N is specified for 6x7. If you're sure it's the lens then you could go longer, a 105mm will certainly cover.

If you're really trying to cover 6x8.5, that's more like 6x9 and you'll certainly need at least a 105mm lens for that.

 

[Ian Grant]

You might look at this thread. There's a few threads on various forums about vignetting with your enlarger.

Ian

 

[Ian C]

The Fujinon 90/4.5 ES enlarging lens properly covers up to 56mm x 72mm (6 x 7cm) and has coverage angle of 53° according to the following source.

http://www.photocornucopia.com/1061.html

Thus, it should be adequate for your stated purpose. If you try to use it with a film-format diagonal in excess of 90mm, then it might vignette the corners. So long as you don’t exceed the 6 x 7cm format, any vignetting you see is due to something other than the lens.

 

[Alan9940]

Like others have already said, I'd suspect something in the enlarger itself first; condenser positioning, etc. That said, all my enlarger lenses are Schneider Componon-S and I've used a 100mm for 6x7 for many, many years without any issues.

 

[Herminus]

Thanks, not at home at the moment but it could be the enlarger, will take a look at those threads (and the enlarger when I get home)

I just assumed the enlarger would take 6x7 because the glass in the holder is 6x8,5 (only one holder and adjustable slides for smaller sizes).

The vignetting is on the longer sides left and right, 6x6 would be fine. Vignetting is also when stopped down.

It’s a 6x7 from my RZ67.

 

[ic-racer]

You might want to measure your mixing box to make sure you have the correct one. Color 4ES looks like a nice enlarger head!

 

[j.c.denton]

If you like to keep the costs low and don't mind a darker image, look out for an old Rodenstock Rodagon 80mm f/5.6. They come in a "zebra" look, are very sharp and cover 6x9.