how critical is lens coating

[Frank_E]

today at a camera swap meet I purchased a 90mm f8 Fujinon SW for the grand sum of $150 which I thought was a good deal. The shutter speeds seemed reasonable and the glass was clean. Didn't notice till I got home and examined it in better light that on the front element about half to 2/3 of the anti-reflective coating seems to have been rubbed off (worn off). So my question is how much of an impact might this have on my shots. I shoot 4x5 and only B&W.

I am aware that in the earlier days lenses were uncoated, however here I am dealing with a situation where the lens seems to be "half coated"

thanks for your feedback

[Armin Seeholzer]

Its no big deal at all, just use the lens an be happy!

Cheers Armin

[Robert A. Zeichner]

Optical coating reduces the amount of light reflected from the surface on which it is deposited. Uncoated glass reflects about 4% of the light striking it. Your lens is made up of a number of glass elements and as long as the rest of them are in good shape, transmission losses should be very minimal. You would do well to use a proper lens shade or better still, a compendium shade to eliminate non-image forming light from reaching the lens and ultimately, the film. People have been making wonderful photographs with totally uncoated lenses for over a hundred years, but still a proper shade will enhance contrast by reducing the unwanted light lying outside of the image area.

[imagedowser]

....... and you'll get better shadow detail. Def. use a shade.

[Bob Salomon]

Coatings are also a metal deposit on the lens that makes it harder to scratch. One of the original reasons for coating was to protect the surfaces.

[cdholden]

I thought coating was originally used for improved contrast in aerial recon sorties.
If used for protection, why do some have a softer coating than others? By design or by accident? My 203mm Ektar is one of the few I've seen that doesn't have coating damage. I've used a few with mottled coatings and some scratched from incorrect cleaning, but none seem to have a noticeable effect on film or paper.

[8x10 user]

I've always found that the coatings on lenses are softer then the glass and scratch easy. Of course there is that Schneider scratch resistant coating.

[Tony Karnezis]

You would do well to use a proper lens shade or better still, a compendium shade to eliminate non-image forming light from reaching the lens and ultimately, the film...a proper shade will enhance contrast by reducing the unwanted light lying outside of the image area.

....... and you'll get better shadow detail. Def. use a shade.

Frank, it sounds like you got a good deal on a nice lens. Here is a very nice article written by Robert demonstrating the effect of a good lens shade.

"Can better shades improve lens performance?
http://web.mac.com/razeichner/RAZP_l...hade_pg_1.html

[GPS]

I've always found that the coatings on lenses are softer then the glass and scratch easy. Of course there is that Schneider scratch resistant coating.

It's just an impression coming from the fact that scratches on a coating are easier to be seen than scratches on uncoated glass. As Bob says modern coatings are harder than the glass itself.

[kirkmacatangay]

Frank,

I was standing beside you when you got that lens. Still kicking myself for not getting it even though I did not have a budget for that type of lens. I do not think there will be an issue because the coating. Shoot with it and see if you like it.

Kirk