Boyer Paris Beryl 90/6.8 a dagor?

[monkeymon]

Some time ago, i got this lens.. just the elements on size #1 adaptors. I liked it, because it's the smallest 90mm wide angle lens i have ever seen/owned. And i seem to end up owning every single small 90mm lens there is.

I got a size #00 shutter for it, and goddam it's tiny! And covers 4x5 nicely!

My actual question is, is it really a dagor type lens? If it is, I'm ever happier because i have never owned a dagor type lens. And it means it's probably even a good lens.. at first i thought it won't be much of use.

I'm also interested in it's value, does it have any? As i only paid 10$ for it.

Attached is a picture of if, comparing it to other well know small 90mm lenses of different designs.

[Dan Fromm]

Yes it is a dagor type. And yes it is a good lens. Beryls are usually overlooked because they're not engraved Doppel Anastigmat Goerz Ser. III Dagor. They usually sell for less than the comparable Dagor. Some years ago I offered a 250/6.8 Beryl here for a lot less that people ask for 10"/6.8 Dagors and didn't get a nibble.

See http://www.galerie-photo.com/boyer-lens-optic.html

Goerz' claim that Dagors cover 85 degrees is exaggerated. Boyer makes the same claim for the Beryl, they exaggerated too. See www.dioptrique.info for calculated coverages and prescriptions. My co-author Eric Beltrando insists that Beryls cover 70 degrees and that for exacting applications such as photoengraving 55 degrees is the most that's usable.

Boyer isn't the only French lens maker who made Dagor clones. Lacour-Berthiot and its successor S.O.M. Berthiot made three dagor types, f/6.8 Perigraphe, f/14 Perigraphe, and Eurygraphe at a variety of maximum apertures. The f/6.8ers are dagors in all but name. Around 1950 S.O.M. Berthiot claimed they covered 65 degrees.

[Ian Greenhalgh]

I've got a 6.8/110 Perigraphe and it illuminates all of the ground glass on my 5x7 camera, but I haven't made any exposures with it yet so I don't know if the outer area is usable or mush. I expect the usable area is no more than a 180mm circle, but maybe at small stops it might be acceptable on 5x7, time will tell.

[Dan Fromm]

I neglected to mention that Boyer sold Beryls as convertible lenses. The cells are identical. A single cell's maximum aperture is f/13 and its focal length is approximately 1.8 times the complete lens' focal length. CEDIS-Boyer's fiches techniques say that a single cell of the 90/6.8 Beryl is 160/13.

Way back when, Lacour-Berthiot sold f/6.8 Perigraphes (f/14ers too) as convertibles. S.O.M. Berthiot's post-WW II propaganda says nothing about Perigraphes' convertibility, offers Eurygraphes (sold as symmetrical lenses and in casket sets with cells of differing focal lengths) as convertible.

Like coverage, convertibility is a sometime thing.

[monkeymon]

Need to test it out, it at least illuminated the whole 4x5". Though i just checked it quickly, but it seemed to have some extra room to play.. so i would think i should cover 4x5". And thus the 85degree would be accurate.

There is something funny about a convertible wide angle lens, i notices the Wollensak EWA 90/12.5 is also convertible, and angulon 90/6.8.. i really much like the fact that so tiny lenses have such elaborate lens designs.

I'll post some results when i have the time to take some pictures with it, first i probably just test it on a scanning back which is a bit short of 4x5". Just to know which of these 90mm lenses is the sharpest and end up on my pocket seneca.

Though, i still should get one of them Super Topcor ER 90/5.6 lenses, it would probably be the best of the small 90mm wide angles.

[Dan Fromm]

Though, i still should get one of them Super Topcor ER 90/5.6 lenses, it would probably be the best of the small 90mm wide angles.

Are you sure about that lens? The catalog (see http://www.cameraeccentric.com/html/info/horseman_2.html , p. 18) says that it just covers 4x5 at f/22. More of a 2x3 than a 4x5 lens. Or perhaps for quarter plate.

If you want a light little 90 that has scads of coverage, look for a 90/14 Perigraphe. These things come in barrel, have to be front mounted, can be jammed into the front of an Ilex #3. S.O.M. Berthiot's most conservative coverage claim for the lens is that it just covers 5x7. Look for a post-WW II one, s/n above around 700,000. Henri Gaud published results of trials with, among other lenses, an ancient and a post-WW-II 90/14 Perigraphe, the newer one was better. This is the least expensive one around http://www.leboncoin.fr/image_son/406143420.htm?ca=12_s right now; I bought my 60/14 from the seller, he's a good guy.

[monkeymon]

I do not actually need any movements, as my camera is more of and point & shoot type.. just the sharpest possible lens that is small as the ones in the picture i posted. I have been using Raptars before, just upgraded to angulon after.. about 10 years of shooting. But i'm now finally building me a camera (based on pocket seneca) that is a little more of a user friendly than my last one, so i kinda like a good lens on this one. But anyhow, i did not buy this lens for the camera.. just was happy to know it is dagor, so now i'm thinking that it might be a contender. I was kinda happy with the 90/6.8 angulon already.. and thought about maybe getting the Super Topcor ER 90/5.6 as it's multicoated and small, probably sharper than any of these older lenses.

Interesting lens that BERTHIOT PERIGRAPHE nevertheless. 60mm might be pretty cool, i'm just really trying to limit my gear and somehow keep my concentration on the shooting part.

I'll need to test this Beryl to know more..

[Dan Fromm]

Aleksi, you say you want a 90. The 60 Perigraphe might just cover 4x5 but it is very difficult to front mount and has considerable of falloff. It will be down nearly 2 2/3 stops in the corner. With lenses that wide, cos^4 bites hard. If you want a 60 mm +/- lens to use on 4x5, modern lenses have great advantages over old ones like mine. Larger maximum apertures, so easier focusing, falloff closer to cos^3 than to cos^4 and available center filters.

If you want a 90, don't be distracted by shorter lenses.