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peter ramm
13-Jun-2011, 18:15
I bought a 200mm Grandagon a little while ago. Lovely lens but not very sharp. I have made a number of exposures, most at f32 and a distance of about 25 feet. I focus carefully but the film is a bit soft. That is true for material in front of and behind the point of focus, so DOF appears fine and I don't think it is a problem with the film plane.

My Apo Sironar S 240mm is tack sharp. What should I expect from the 200mm? Can one send such lenses to anyone to check cell spacings etc?

Peter

Steve Hamley
13-Jun-2011, 18:44
Give it a try at say f:16.

S.K. Grimes might have the cell spacing recorded. Do you know if the shutter is original?

Cheers, Steve

MIke Sherck
14-Jun-2011, 06:55
I have the older Fujinon 210mm, single coated, with 352mm of coverage. It is tack-sharp. I love this focal length for 8x10!

Mike

IanG
14-Jun-2011, 07:18
It should be very sharp at f22. The cell spacings are factory set and not always identical. My 90mm Grandagon has brass spacer rings, it's possible to loose them if your not careful when fitting cells into a shutter.

Ian

mcfactor
14-Jun-2011, 11:02
My Caltar-N 210 (a rodenstock sironar-n) is perfectly sharp all the way to the corners and covers 8x10 easily.

peter ramm
16-Jun-2011, 07:29
Thanks. The lens appears to be in great shape and in its original shutter, but who knows. There may well be a spacing issue. Any ideas as to someone who can check this out?

Armin Seeholzer
16-Jun-2011, 08:00
My Caltar-N 210 (a rodenstock sironar-n) is perfectly sharp all the way to the corners and covers 8x10 easily.

This is not a wide angle typ of lens, but my 155 mm Grandagon is tak sharp and also should be a 200mm!
But it need a strong front standard!

Cheers Armin

Louis Pacilla
16-Jun-2011, 09:57
This is not a wide angle typ of lens, but my 155 mm Grandagon is tak sharp and also should be a 200mm!
But it need a strong front standard!

Cheers Armin

I agree with Armin. I also own & use a 155 Grandagon N & I find it's razor sharp all the way to edges of the image circle. I see no reason why the 200mm Grandagon would not preform equally as well if it's spaced correctly.

It may be worth your time to send it off to SK Grimes or even better a Rodenstock trained repair center( If that exists) To have it put on an optical bench & spacers then added as needed. You may find out that no problem is found & then Maybe it's operator error. It can happen.:)

peter ramm
16-Jun-2011, 10:21
The 200mm has a large IC and lots of complex glass in it. That affects its potential to be sharp, as the attached MTF data show (supplied by my friendly local Rodenstock dealer).

Difficult part here is that all of my previous experience is with very sharp lenses and I may just be seeing what is normal for a lens with a 500mm IC. Hate to send it Germany if there is nothing wrong but I guess I will have to do that or live with the uncertainty.

Ole Tjugen
16-Jun-2011, 12:30
A WA lens should be as sharp as a normal lens, if not sharper. Central sharpness, at least should be VERY sharp.

IN all the lenses I have used, only a very few very fast lenses have been visibly unsharp, unless tortured well beyond their intended use - or perhaps due to operator error.

Is your GG and film plane exactly in the same place? The shorter the lens, the more critical that is - what gives tack sharp pictures with a 300mm lens might well be far out of tolerance with a very wide lens.

IanG
16-Jun-2011, 13:28
Peter, can you get someone else near you to give the lens a try, perhaps on a different camera, or you borrow (or hire) a different camera

I'm not familiar with the 200mm Grandagon but my 165mm Super Angulon is very heavy, and I'd guess your lens is no lighter.

You need to eliminate any potential camera errors, register as Ole mentions, lack of rigidity causing almost unnoticeable camera shake etc. It takes very little to lose critical sharpness, with my Mamiya 645's on a tripod it's was aas simple as not using mirror lock even with quite short exposures 1/60th, 1/30th and slower.

Ian

Richard K.
16-Jun-2011, 13:30
Peter, I managed to have been offered one of these (Grandagon 200) for a decent price so I went ahead and bought it despite the size and weight I really wanted it to be bad so that I could get the lighter and smaller 210 SSXL at significantly more money but darn if it isn't sharp corner to corner (on 10x12), even with moderate movements. It also seems to have less light fall -off than my memory of the 210 SSXL (I had a great one whenI had a 11x14 but sold both) but I may be wrong here. So, yeah it can be a very sharp lens with great coverage and good illumination. It doesn't exactly snap into focus on the GG, so careful focusing is needed.

peter ramm
16-Jun-2011, 15:46
Good points. It is possible I have a stability issue. I have the P2 mounted on a Sinar plate with two rail clamps, but that mounts on a Sinar head on top of a five series Gitzo. That's quite a bit of weight and kind of .... springy. I did notice that on one plate some of the material at the lower part showed obvious doubling. I attributed it to an aggressive tilt because it was limited to one part of the image. Maybe the tilt was exagerrating something happening all over.

Let me put the whole thing on the Foba stand and try it. Only reason I haven't done that is I have been shooting outside. Not the Foba's forte.

Richard, let's have a grandagon party and compare our optics. Im just down the road in Niagara. PM me if you're interested.

Darryl Baird
17-Jun-2011, 17:49
your current equipment mirrors mine and I have few (if any) stability issues. Focus seems more likely. my two cents...

peter ramm
18-Jun-2011, 11:17
Shot the same subject on the Foba stand. Image is definitley sharper, more what I would expect. Not as sharp as a Sironar S but fine considering the IC and field of view. I think I must have had some wind on the camera the other day. Overpowered the stabilizing effect of the Gitzo.

Lots to love in this optic, pun intended.

Richard K.
18-Jun-2011, 14:08
Richard, let's have a grandagon party and compare our optics. Im just down the road in Niagara. PM me if you're interested.

I should be able to head out that way in the next couple of weeks....I'll PM you to arrange a time, closer to then. :)

John NYC
18-Jun-2011, 16:02
I had a 150mm SS XL for a while, and it was certainly sharp. While, as Ole said, the central sharpness was ridiculously good, the edge sharpness especially blew away any 35mm equivalent in focal length. There is something to be said for the brute force approach of 8x10 film.

peter ramm
30-Aug-2011, 06:33
I have been thinking more about this. Made a few shots with the 200mm on an IFF studio stand and results are a bit better, but still not super sharp. Perhaps it comes down to the large reduction ratio of the 200mm lens. There is just a lot of stuff in there to be resolved.

I am shooting pictures of mechanisms, with lots of sharp transitions across screw heads, seams and the like. Point is to get the sense of detail that 8 x 10 can provide. However, it is exactly this type of detail that will suffer as scanner MTF interacts with everything else. Let's propose a couple of hypothetical examples. In each case, the the film/lens are giving me 70% MTF at my spatial frequencies.

a) .7 F/L MTF x .6 scanner MTF = 0.42 system MTF (hypothetical Epson)
b) .7 F/L MTF x .8 scanner MTF = 0.56 system MTF (hypothetical drum)

Just examples. Not sure what the Epson is really doing to modulation across a bunch of slotted screws, but it doesn't take much degradation to really soften the image. The test, of course, is a drum scan. Not sure any of my efforts are worth that.

TheDeardorffGuy
30-Aug-2011, 10:50
I have been thinking more about this. Made a few shots with the 200mm on an IFF studio stand and results are a bit better, but still not super sharp. Perhaps it comes down to the large reduction ratio of the 200mm lens. There is just a lot of stuff in there to be resolved.

I am shooting pictures of mechanisms, with lots of sharp transitions across screw heads, seams and the like. Point is to get the sense of detail that 8 x 10 can provide. However, it is exactly this type of detail that will suffer as scanner MTF interacts with everything else. Let's propose a couple of hypothetical examples. In each case, the the film/lens are giving me 70% MTF at my spatial frequencies.

a) .7 F/L MTF x .6 scanner MTF = 0.42 system MTF (hypothetical Epson)
b) .7 F/L MTF x .8 scanner MTF = 0.56 system MTF (hypothetical drum)

Just examples. Not sure what the Epson is really doing to modulation across a bunch of slotted screws, but it doesn't take much degradation to really soften the image. The test, of course, is a drum scan. Not sure any of my efforts are worth that.

I've done several CLA on these. They are very sharp. The "f stop sweet spot" seems to be between 16 and 22 closer to 16 in a open to close movement, I thought maybe there was some difraction at 32. That would degrade sharp edges..i

Robert H
13-Mar-2014, 17:19
As much as I have admired the 200 from a distance, I must confess I've heard the 155 is in fact a better performer regarding sharpness. The MTF curves also suggest this but had always assumed the real life differences were marginal.

8x10 user
13-Mar-2014, 17:33
I have moved away from 8x10 for field use but back in the day I used a 150 SSXL, 210mm Sironar W, and 360 Sironar S... All three were very sharp. I think the 210, and 360 were slightly sharper but other factors could have been at play. At the right aperture I'd say these lenses are capable of roughly 3000PPI (based on high resolution scans and my 10x Schneider loupe).