Fuji. W 150 5.6 vs Symar S 150 5.6 image circle

[John Chang]

Regarding the image circle of these lenses, I see conflicting info:

For the Fujinon, I have seen from 224 (http://www.thalmann.com/largeformat/mid-rang.htm) to 245 (http://members.aol.com/subgallery/byseries.htm)

For the Shneider, most of what I read is 210 (including
Schneider's own page:
http://www.schneideroptics.com/info/vintage_lens_data/)
But I have also seen it at 220:
http://www.largeformatphotography.info/lenses/LF4x5in.html
(This page lists the 150mm APO-Symmar, which I am told is the
same thing as the modern Symmar S).

Can anybody comment on whether the Fujinon really does give appreciably more *usable*
(ie. not suffering from light fall-off) image circle? I suspect this because the Symmar
tends to cost as much or more, and I've read Schneider is known to be modest in their
image circle numbers, whereas Fujinon can be "optimistic" as Mr. Thalman writes.

Any other comments on comparing the two?

Thanks.

[Nick_3536]

The Fujis come in different versions. The higher number is the older single coated version. Newer versions have the smaller coverage.

[Oren Grad]

This page lists the 150mm APO-Symmar, which I am told is the same thing as the modern Symmar S

They're both fine lenses, but they're not the same. The Apo-Symmar is a later design specified to cover 72 degrees rather than 70 degrees as with the Symmar-S, hence the larger image circle. Details of both are available on the Schneider Optics site - the Apo Symmar is still listed under the current photography products, even though it's out of production.

[Walter Foscari]

" ... whereas Fujinon can be optimistic..."
That is certainly true for the older single coated version (writings on the inside of the filter ring). Stay away from those if you are concerned with coverage. Data for the newer series on the other hand has always been close to the truth in my experience.

[Steve Hamley]

A wide(r)-angle plasmat will suffer additional light fall off beyond the image circle of a narrow-angle plasmat according to the laws of physics. All lenses, at least of a given design, will exhibit essentially the same amount of light fall off given the same amount of coverage, so more coverage also equates to more light fall off in the increased part of the image circle - no free ride from one manufacturer versus the other.

Steve

[Mike Kovacs]

Steve, does that not force the manufacturers to decide exactly how fuzzy the image is where "coverage" is deemed to end?

[Dan Fromm]

Mike, go visit Schneider's site. What they do is pretty clear and somewhat scary. Coverage ends where the MTF at quite low frequency is tiny. Without going there again to check, I recall that tiny is roughly 20%, and at that point the MTF curves are near vertical.

Rodenstock, IIRC and I could be wrong, does much the same. Except, that is, in the case of Apo Rodagon Ds. When I had a 1:1 75/4 I looked up its MTF chart, which turned out to look like the central part of a wide angle lens' MTF chart, i.e., very flat curves to the edge. No image at all past the edge, though, because of a field stop. No question about what that lens covers. Not enough for my purposes, alas.

Cheers,

Dan

[Bob Salomon]

"Apo Rodagon Ds. When I had a 1:1 75/4 I looked up its MTF"

There is also a 75mm 4.5 Apo Rodagon D as well as a 120mm Apo Rodagon D. Did you check the curves for these as well?

[Mike Kovacs]

I couldn't find any MTF charts on the schneideroptics.com website for the Symmar and Symmar-S. I don't think they exhibit as sharp a falloff as the more modern LF optics.

[Michael Gudzinowicz]

John,

What is the filter size of the Fujinon 150? See the following table for identification
of the different versions and their specs.

http://members.aol.com/subgallery/byfl.htm

The Symmar S is a good MC lens, but it isn't identical to the APO, and is
well removed from the plain Symmar.

Mike