Dropped a lens! Is it damaged?

[tedw6]

So I had my Linhof Techno on a tripod at the edge of a 12 foot drop. Yes, it fell off and landed on a Rodenstock 65mm Grandagon-N. The camera was fine, but the edge of the lens was bent. The lens did not obviously hit on the glass but on the metal lens barrel.

I figured it was toast. To test it, I borrowed a Grandagon MC (older version) from a buddy and shot the same image with both lenses on Adox 100 developed in Rodinal 1:100.

I can't tell the difference between the two negatives.

So, to make the lens a user, I bent out the metal with needlenose pliers and permanently installed a 58->62 stepup ring.

Am I fooling myself or is the lens okay?

Thanks.

Ted

[Jac@stafford.net]

So, to make the lens a user, I bent out the metal with needlenose pliers and permanently installed a 58->62 stepup ring.

Am I fooling myself or is the lens okay?

The general rule is to test the lens after the very latest thing that happened to it, which in your case is bending the metal. Test again.
.

[Alan Gales]

It may be fine. It all depends upon how it hit and how hard.

I once owned a Zeiss zoom for a Contax 35mm camera that had the same thing happen to it. A small piece of the lens barrel where you screw in the filters had broken off but the lens performed fine and you could still screw in filters.

[diversey]

I think your lens is fine since you have tested it. I had a similar lens drop as you had for my Leica lens.

[BrianShaw]

If you can't see a problem then you aren't fooling yourself at all. I have a 90 Schneider that i bought cheap because of a bent rim. I've never seen anything to make me thing there's a problem. Your resale value just plummeted, though.

[Bill_1856]

Congratulations!

[Sirius Glass]

Your lens is ok, but do not make a habit out of bending the lens ring.

[tjvitale]

If you could get a digital scanback on your view camera with that lens, you can check alignment by going to very high resolution on an area of high contrast and checking the red, blue and green channels of the image within Photoshop. At very high magnification, cycle through individual (1) red, (2) blue and (3) green channels, within Photoshop, so that only one color of light is being examined. The physical position of the thing (edge of a letter or a simple crossed-line target) being examined will shift depending on the color of the light. This process looks for chromatic aberrations (CA), where the various colors of light focus. Better lenses will have less chromatic aberrations.

If a portion of the field has been changed, relative to another corner, it "may" show up as more CA.

Also, examining image detail quality under high magnification, especially when compared to a similar lens, may reveal if there is an issue. Obviously, this would be a better test if you had a similar digital image from a time when the lens had not suffered a drop.

I would not assume image quality has not changed, only that it is not glaringly visible. Sorry!

On the other hand, the lens barrel of a large format lens is quite robust. If a cylinder with several solid elements (individual lens elements) holding its cylindrical shape is dropped on a corner, it is quite possible that it will not distort. But, think of how may times you have seen a car frame look bent after an accident. In addition, the filter ring riser acts as a shock absorber, crumpling preferentially, such as a collapsible steering column, during high load.

Film can be very forgiving. High resolution digital is devastating. I had to stop using several lenses after I saw this test used on them. In the real world, these CAs just show up as softness.

Tim Vitale
Oakland, CA