150 does not cover enough ?

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I called a photo store looking for a used lens of 150mm. The owner said that with 150mm I would have such minimal coverage that I would not be able to use any movements without vingetting, and that 150mm is strictly for copy work. Am I right to think this is absurd? The 4x5 film is, according to my Zone VI catalogue, 6 1/2 inches in diameter, or 161mm. The lens I will purchase has 231mm image circle, so would this lens be just fine? Thanks for any feedback on this. Raven

-- Raven (mtand13@netreach.net), July 18, 1999


Response to focal lengh question

Yes. You are correct in thinking that the camera store owner's (I can't believe a store OWNER would say such a thing.) opinion is absurd. I own a 159mm lens which covers 8x10, and there are plenty of 90mm, 75mm and even some 65mm lenses which cover 4x5. Amazing.

-- Chad Jarvis (cjarvis@nas.edu), July 18, 1999.

Response to focal lengh question

Think of the light coming out of the back of the lens as a cone, the apex of which is the nodal point of the lens. The further away your film plane is from the apex the wider the projected image circle is. When you are doing close up or macro photography, the plane where the image is sharply focused is positioned further away from the nodal point than when you are making images which are not closeup

So it depends on whether that 231mm image circle has been measured at a close focusing or even macro distance as opposed to situations where the subject is farther away from the camera (head and shoulders portraits to landscapes).

Assumming you are talking about getting the Rodenstock Apo-Sironar S 150mm f/5.6 (which has a published image circle of 231mm @ f/22), and since this is promoted as "a universal lens" and not specifically a macro lens, you should say "balls" to the camera store and move on. But since this is also a relatively new design, you might have trouble finding it used. Most standard 150mm lens designs (from Nikon, Rodenstock & Schneider) have published image circles ranging from 210mm to 220mm. There is also a price (in cash, about 40% more) to pay for the slightly larger image circle of Apo-Sironar S, but if you need it, you need it.

-- Ellis Vener (evphoto@insync.net), July 18, 1999.

Response to focal lengh question

Raven, Vignetting should not be a problem in most situations. Your logic is correct.

My 135 mm has only 200 mm of coverage and I have never had a problem using it for landscape photography. 231 mm may not be enough for some table top compositions involving tilt and rise/fall if your camera height is near the height of the table. IF you think that's an issue, you could consider a 155 mm f6.8 Grandagon-W, which would have a 382 mm image circle. But you would pay a significant penalty in weight. It weighs 1460 g, vs 250 g for the 150 mm S. It's front filter is 105 mm, so there's a lot of glass there. Personally, I'd stay with the 150 mm S if you want that focal length.

A better alternative would be to move to a longer focal length lens, such as Rodenstock's 180 mm N has a 262 mm image circle (400 g), or the 180 mm S with a 276 mm image circle (410 g). Other brands are comparable.

I'm not sure what drove you to the 150 mm focal length, and how important that is. I started with a 90 mm, and then added a 210 mm. But we're all different.

Hope this helps. Bruce

-- Bruce M. Herman (bherman@arctic.net), July 18, 1999.

Response to focal lengh question

If the store owner was only familiar with the Schneider 150 Xenar then perhaps he would think that the image circle of the 150mm focal length would be smallish, and once something like this gets into your head it may never be corrected.

But the truth is that modern Schnieder's (APO-Symmar, not Xenar), Rodenstock's, Nikkor's and Fuji's all offer 150mm lenses with tons of image circle. Even the Xenar offers a little bit of movement and it's far less than 231mm of image circle.

-- David Grandy (dgrandy@accesscable.net), July 18, 1999.

> 150mm I would have such minimal coverage that I would not be able to use any movements without vingetting, and that 150mm is strictly for copy work.

That's ridiculous, but to give the store owner the benefit of the doubt he may have been thinking of old press-camera lenses, many of which didn't exactly abound in coverage.

-- John Hicks / John's Camera Shop (jbh@magicnet.net), July 18, 1999.

To add to Mr. Hicks' comments -- anyone remember the old Ektar 135/4.7 or whatever it was that was mounted on the old Speed Graphics?

Heh. Don't try to shift those.

But most modern 150mm, LF-specific lenses should cover 4x5 without a problem. -jon

-- j. law (jrl@blast.princeton.edu), July 19, 1999.

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