Multicoating coming off?

I bought a Sinaron-S 5.6 MC from eBay and I see what appears to be

pinhead or larger spots where the multi-coating looks have flaked off.

If is difficult to see, and in fact, can't be seen unless you get the

light reflecting off the lens at just the right angle.

 

Is this something I should be concerned about: 1. at all, 2. only in

case of potential flare conditions, or 3. not at all?

 

I haven't had the chance to test the lens under shooting conditions,

and would greatly appreciate the opinions of this group before I do so

and/or contact the seller. I seem to remember somewhere in the past

reading that this is a common manufacturing condition that is not

significant, but I could be dreaming it up.

 

Other than that, the lens is without scratches or fungus or other

visible problems, and seem to focus well on the ground glass.

 

Many thanks for your opinions.

if you plan on using this lens for paid work, i'd test it thoroughly under different lighting conditions beforehand. most likely it won't have any negative effects, but it "could" have an effect on color rendition and flare resistance. that's something i'd want to be absolutely sure about before using on an assignment.

Having the multicoating flake off is not a common problem. The common problem that you may be thinking of is for specks of the black edging paint to detach from the edge of the lens elements. This is fairly common on Schneider lenses from a certain era and so has acquired the nickname "Schneideritis", but can occur on lenses of other brands. But this isn't a problem with the optical coating.

 

As long as the area of the missing coating is very small, the effects should be very small. But normally defects like these make a disproportionate impact on the price of the lens. So if you paid the price of a perfect used lens, you might want to consider returning the lens or asking for a price adjustment.

 

Your lens is a renamed Apo-Sironar-N -- http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=004am3

some guys use canned air to clean dust of lenses.. if a piece of quartz dust gets in the tube and you spray the lens its like shooting it with a gun.. i know becouse ive done it.. it wont affect the final product, mutlicoating as i understand it enhanses light pennetration of the lens, so a tiny spot on the print with slightly less light wont noticibley decrease quality. i had a bubble in a lens that i had bought from canon.. i paid a whole lot for it and was upset so i called canon.. they said to take a photo and circle the problem on the print and they would probably replace the lense.. that was the end of that, could never find anything.... dave...