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komatsu
9-Mar-2019, 13:56
The following image is from a 300mm f/3.5 Goerz Hypar. I'm really enjoying this lens but it's got me thinking. As far as I know, the following are all of a similar design: the Steinheil Cassar, the Rodenstock Eurygon, the Berthiot Stellor, the Meyer Trioplan, the Wollensak Varium, the 3-element Perscheid and (of course) the various Cooke triplets.

My question is: do all these lenses exhibit a similar level of softness or are there more pronounced examples. I'm keen on the reasonably restrained look of the Hypar, and I'm especially curious to know if it applies to the Varium and Perscheid.

(BTW: virtually all the Perscheid shots I've seen on line do not differentiate as to which version of the lens is being utilised.)

Thanks (hopefully) in advance,

Leo

https://farm8.staticflickr.com/7875/46340531195_b51beb8334_z.jpg (https://flic.kr/p/2dAXkrM)Morris (https://flic.kr/p/2dAXkrM) by Leo Velimir Brancovich (https://www.flickr.com/photos/55873497@N04/), on Flickr

Dan Fromm
9-Mar-2019, 15:40
Leo, be careful when speaking of Berthiot Stellors. There were two series, Ia and Ib.

Ser. Ia was initially (from 1912 to 1936) a four element airspaced anastigmat reminiscent of the Zeiss Unar. All focal lengths were f/3.5.

Ser. Ia (1936-on) is a triplet. All but the two longest focal lengths are f/3.5. Tthe two longest, 315 and 360 mm, are f/4.

And then there's Ser. 1b, with all but the two longest focal lengths f/4 and the two longest, 360 and 480 mm, f/4.4. This is more-or-less a Tessar with three instead of two cemented elements in the rear cell.

Confusing nomenclature, eh?

Rodentsock's Eurygon is a trade name that covered a number of design types. Gotta be careful when speaking about them too.

Whir-Click
9-Mar-2019, 16:19
I don’t have examples of the Varium to share, but it is interesting to note that Wollensak pitched this line of lenses as a mid-point between the softness of the Verito and the sharpness of the Velostigmat Series II. Perhaps consistent with the “reasonably restrained” softness you mention.

Here is the description from a 1926 Wollensak publication:
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komatsu
10-Mar-2019, 00:18
Thanks Dan,

I knew about the Eurygons as they are visibly different (I assume those dinky little things are enlarger lenses?). The Stellor, however, is quite a surprise. You may have saved me some future disappointment!

Thanks,

Leo

komatsu
10-Mar-2019, 00:23
Thanks a lot "Whir-Click"! I've seen the Hypars and Eurygons advertised this way. It's as though they're selling a "defect" of these designs as though it was a desirable quality (which for many, it is!). Your post is a good clue regarding the Varium. Now, what about the Perscheid.....

Leo

Jason Greenberg Motamedi
10-Mar-2019, 10:19
I don't have a scanned image, but I have a 16" f3.5 Varium, and it is softer at f3.5 than the image you posted. Although they look a bit different, a Varium at f3.5 has the halation (diffuse highlights) of a 16" Verito around f8, or thereabouts. Noticeable but not overwhelming. It is a great and very large lens (needs at least a 8" lensboard).

The Trioplan and Cassar (both 210/3.5) lenses I owned were triplets, but not soft focus lenses. They weren't very sharp at f3.5, but certainly were not intentionally soft focus and didn't have halation.

The Cooke (270/4.5 IIE) that I own looks very different when it is defocused than the Varium. The Cooke seems too lose its hard lines when softness is increased, but doesn't have much halation.

jp
10-Mar-2019, 12:00
I have the 210 trioplan and consider it smooth not soft or sharp. sorta like the photo at the start of the thread.

https://www.flickr.com/search/?user_id=13759696%40N02&sort=date-taken-desc&text=trioplan&view_all=1

If you wanted a little bit sharper, go for a tessar or RR. If you want a little bit softer the Fuji soft focus triplet which I think is not soft enough.

komatsu
10-Mar-2019, 14:49
My word, I think you nailed at least part of it it! That puts the Trioplan, Cassar, Eurgon (triplet) and Hypar in a distinct group. It may be these are all "soft" due to the inherent fallibility of the triplet formula at 4.5 - 3.5. It seems like the Varium may be doing something else, which squares with the (few) images I've seen.

Thanks to everyone for these highly enlightening answers.

Leo

komatsu
10-Mar-2019, 14:53
...but can anyone enlighten us all on the Perscheid triple?

Leo