Rodenstock 90mm 6.8 grandagon...distortion, bag bellow, center filter?

[adam_mirko]

Dear all,

 

as I'm new in large format, I've already got great answer to my old post, and now I

have more clear ideas about the focal lens that I have to buy to begin.

 

A 90mm.

 

I'm attracted from Rodenstock 90mm 6.8 N, or 4.5 version lens.

 

 

I'm going to take urban landscape pictures that include Buildings, Perpendicuar

architectures, and also night views with neons and lights.

 

All that I want from my lens is all that everybody (I suppose) want:

 

1) Full details

2) Less fall of light at edges

3) Very low, or not Distortion at border of lens

 

My pictures are often really graphic and geometric, so I need a lens that doesn't get

distortion perpendicular lines (for example when I take pictures of alot skyscraper's

windows)...I need also to know if it's possible correct with photoshop the fall of light on

the edges.

 

Is the center filter and the wide angle bellow necessary with the 4x5 format?

 

Thank You in advance.

 

The motivation that I'd chose the Grandagon 6.8 instead of the 4.5 is about the price:

 

if I buy the Grandagon 90mm 6.8 I can buy also the 210mm Apo Sironar N because I

need these 2 focals.

 

But I don't know if will be a right choise to save money buying these 2 lenses or buying

only the 90mm 4.5 Grandagon and wait 1 year to buy the 210mm Apo Sironar N...

 

Can someone help me?

 

Thank You in advance

 

Adam Mirko

[r_fos]

I've used the 90 Grandagon N for a few years and I don't think the vignetting is too

objectionable. That being said...yes you can affect the vignetting in photoshop, but it's

not an exact science. That is, a flawless effect is not always what you end up with.

Overall, I think it's a great lens: compact, sharp & minimal (if any) distortion. I've been

pleased with it. The only con to the lens has been focusing with it in dim lighting. It's

a bit difficult even with an upgraded viewing screen. Bag bellows...I don't have one on

my Ebony, but I do have a recessed lens board on the 90 Grandagon. That seems to

work fine. Good luck in making a decision

[michael_briggs2]

Whether you "need" a center filter depends on you and your uses of the lens rather than being an inherent characteristic of the lens. All lenses have non-uniform illumination of a function of distance off-axis, in all formats. Somehow people get concerned about this in LF photography, probably because center filters are available. Whether you will find a center filter useful depends on the focal length vs the format, the extent of movements such as front rise that you use, whether you use negative or transparency film (negative has more exposure latitude), etc. That said, probably only a small fraction of 4x5 photographers use a center filter with 90 mm lenses. Modern designs, such as the Grandagon-N, Super-Angulon, Nikkor-SW and Fuji-SW, use optical methods to improve the uniformity of illumation. (But not the old, plain Angulon, nor the more recent Super-Symmar-XL.)

 

Nothing stops you from buying a 90 mm and a 210 mm lens. That is a rather big step in focal length.

 

Probably you should just buy something and find what you want for your photography. After taking photos for awhile, you may decide that a 90 mm lens is too wide. We can't predict that for you.

 

Very few LF cameras can use a 90 mm lens and a 210 mm to their full potentials with a single bellows. A regular, pleated bellows long enough to do a good job with a 210 mm lens will typically be too compressed at 90 mm to allow full movements. But you can buy a 90 mm lens and see what your camera with its current bellows can do. If it seems like your are straining the bellows when you apply movements that the 90 mm lens can support, then you would be better off with the bag bellows. This is the same answer that you got to your previous question about the 110 mm lens.

 

The Grandagon-N / Super-Angulon / Nikkor-SW / Fuji-SW lenses generally have very low distortion. This is using the term "distortion" in the meaning of rendering straight lines in the scene as straight lines in the image. One reason for this is that the designs are approximately symmetrical, unlike the retro-focus designs required in SLR cameras. The PDF datasheet available from Rodenstock's website has a graph of the distortion for the 90 mm f4.5 Grandagon-N. At large subject distances the distortion is very low. The f6.8 version is likely fairly similar.

[leonard_evens]

I have the 90 mm f/6.8 Grandagon_N. I am very happy with it, and I use it pretty often. Its coverage is adequate for my purposes, particularly since movements with the bellows so compressed are somewhat limited for my camera..

 

I used it for several years without a center filter. But at one point I got the 75 mm, f/4.5 Grandagon-N, because I found stiutations where the 90 mm lens wouldn't let me get as close as I needed to be. I probably could have managed without a center filter for the 75 mm lens, at least of landscapes, but I found that in architectural photography, my pictures would show color shifs at the periphery because of different degrees of fall of illumination. So, I finally got a center filter. Since the same filter works on the 90 mm lens, I now use it pretty regularly, but if I didn't have the 75 mm lens, I wouldn't have gotten it.

[big toys are better]

One thing to note is that the aperture's extra half-a-stop in the 90mm Grandagon f/6.8 does make a difference in focusing over the f/8 Nikon and Schneider options (as does the f/4.5 Grandagon over other 90mm WAs).

[michael_briggs2]

I used an f8 90 mm lens for years (a Nikkor-SW). Perhaps because I mostly used it outdoors during daylight hours, I didn't find it that hard to use. One key is to have a fully opaque darkcloth. Short focal length lenses are harder -- I tilt my head to match the angle that the light rays reach the ground glass and so don't see the entire image at once. Inside or at dawn/dusk, a faster lens might be easier. But at some point you will want to check the depth of field at f16, f22, ... and the image will be very dim, regardless of the maximum aperture of the lens.

 

You have now asked about 90 mm, 110 mm and 135 mm lenses for your wide-angle choice (http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00Plnb & http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00PnwK ). Starting with one wide-angle and wanting to do architecture, a 90 mm is probably the best choice (for 4x5). My most frequently used 4x5 wide-angle is 110, but I have a wider lens to use when that lens isn't wide enough. 90 mm lenses are less costly; you can always crop if the lens is too wide but you can't as easily add onto the film (though in the digital era you can try stitching). Lenses shorter than 90 mm are harder to use.

[ashton_lee3]

I've always used f8.0 90's and they work fine... particularly if you have a decent "Brightscreen" or other efficient groundglass with fresnel. You'll always stop a lens down anyway, the the faster lenses are huge and heavy. Buy a used F 8 lens and you'll have the money for a few more lenses... say a 135 and a 210. I find I use a 135 more than a 90 even for buildings. You can use movements to tame a 90, but you'll still get way more distortion than moving back and using a 135 or longer lens, whenever that is possible.

 

The people who like center filters best are those who sell them. You very likely will never feel the need for one.

 

Don't assume older lenses are inferior. The Kodak Wide Field Ektars, and Commercial Ektars are still competitive as are many discontinued designs from all the majors. I'd much rather have a quiver of 3-4 15-30 year old lenses than just 1-2 new lenses.

 

You will probably want a camera with a bag bellows option... or a Deardorff which has the wonderful sliding lens board, which can give you rise independently of the bellows.

[brucecahn]

I have had a Schneider 6.8, the current one, called the classic. Except for the speed it is as good a 90mm as I have used, unusually sharp, no readily apparent distortion. Currently have the Rodagon 4.5 n. It is also a great lens. The extra speed is quite usable. The lens may be used at f8. If you need the speed get the 4.5. Otherwise the other lens is at least as good. I have not used the Rodenstock 6,8. The faster lens is quite heavier and more bulky.

[andresainderichin]

The Rodenstock is wonderful, (but the f4.5 is huge). I never bothered about the center filter (it's very expensive), and

never felt distortion was a problem. Since I do most of my photos indoors, the 90mm is almost standard for me. I need

movement, so the bag bellows is realy useful.