Gundlach Radar Anastigmat 8x10 users

[benrains]

Does anyone else have first-hand experience with using the Gundlach Radar 12"/4.5 lens? I acquired one about a year ago as sort of a "bonus" that came along with a camera. I hadn't tried it out until just this past weekend, and used it for some full length portraits in a studio setting. The results I'm got are a little disappointing (which is saying a lot for me, because I'm pretty ok with the other run-of-the-mill lenses from the same era.)

Specifically, even at those relatively close distances where the image circle should be larger, I'm finding the lens vignettes in the corners of my 8x10 film, and the sharpness falls off noticeably before then... even at apertures of f/11 and f/16. I'd say it's maybe a reasonable lens for 6.5x8.5 and 5x7 work, but 8x10 seems overly optimistic. With similar true Tessar designs, like the Zeiss Tessar 300mm/4.5 and the Wollensak Velostigmat 12"/4.5 I've not run into those kind of problems. Just curious if maybe I've a bum example, or if this is normal for the lens.

[BrianShaw]

I have used a Gundlach Radar in shorter focal length (190mm) on 4x5 and have been happy with its performance, but that was landscapes so it was at infinity focus. Mine was even dropped rather severly in the past as evidenced by a big dent on the front ring. One of these days I'll have to try it for portraits to see if I encounter issues like you have.

The 12 inch lens that I've been using that I LOVE is the Kodak commercial Ektar. I've only used that for portraiture on 4x5. Might be worth a try on an 8x10 to see if it resolves some of the issues your encountering.

... or maybe you havve a bum example, as you say.

[ic-racer]

Did you try f45? There is a brochure on that lense here (Grundlach catalog).:http://www.cameraeccentric.com/html/info/korona_2.html

[William Whitaker]

...even at those relatively close distances where the image circle should be larger, I'm finding the lens vignettes in the corners of my 8x10 film, and the sharpness falls off noticeably before then...

Concerning the vignetting, I was going to ask if you got a "bonus" hood, too. But the sharpness issue suggests something more sinister. Has the lens perhaps been disassembled and then reassembled incorrectly? I have that lens, but can't get to it before next week. Someone else may be able to compare theirs to yours before then.

[Jim Noel]

I have never used my Radar at an opening larger than f 32. I don't have the problems you mention.

[Steven Tribe]

The Radar is (according to VM) a modified tessar with the rear group being made up of 3 glued lenses. It is not unknown for one of the lenses to have become delaminated and removed by a previous owner. It would still work (?) but the focal length would be changed a ltlle and the coverage, perhaps, altered. Perhaps you should also check the orientation of the second of the two lenses in the front?

[benrains]

Thanks for the feedback on this. I'll more closely inspect the lens, particularly the front group, to make sure everything is in proper order. The glass is clear, and the focal length is appropriate for the claimed 12", so I think all the lenses must be present.

It's possible that at the small apertures it'll perform better, but I'd have expected a lens explicitly marketed for use on 8x10 would at least fully illuminate the format (even if not sharply). Unless I find something obviously wrong with the lens, that I can fix, I'll stick to using my Zeiss Tessar 30cm or the Velostigmat 12". Sort of a shame though because the Betax No.5 shutter on the Radar works perfectly.

[Jim Graves]

I also have this lens in a Betax 5 shutter. I put it on my Kodak 2D today and had no trouble illuminating the corners @ f-4.5 at infinity ... even with 3" of rise. At 4" of rise it is getting dim on the corners but illuminates them.

I'll try to get my scanner up and running ... I'm sure I have an example around here somewhere.

[Jim Graves]

Here's the only full-frame 8x10 I've got on file for this lens.

Taken at the California Automobile Museum in Sacramento. Kodak 2d, Gundlach Radar Anastigmat 8x10 (approx. 12"), Betax 5 shutter, @ f-4.5 for 7 seconds. 1937 Cadillac.

[Jim Galli]

Here's the only full-frame 8x10 I've got on file for this lens.

Taken at the California Automobile Museum in Sacramento. Kodak 2d, Gundlach Radar Anastigmat 8x10 (approx. 12"), Betax 5 shutter, @ f-4.5 for 7 seconds. 1937 Cadillac.

VEry nice glow Jim. Mine always covered 8X10 fine.