Effect of cleaning marks/spots on rear lens?

[youngcoby]

Hello,
in several topics, the bad state of a front lens has been well documented. It's effect on picture quality is rather small.

Can the same be said for spots or cleaning marks on the rear lens? I guess this is more critical (closer to the sensor/film, together with a smaller total area of the lens), but I'm not sure.

Someone could help me out here?
Filip

[eddieitman]

Well i have a Jupiter 11a that has what can only described as a Wet petrol look on the back element where the coating is damaged.
Take a look at the section on my site for that lens and i hope that it answers your question.
I will try and take a picture of it when i am home for you
http://digital-darkroom.weebly.com/russian-jupiter-11a-1972.html

[martyn_bannister]

Only way to say would be to take identical lenses, one without damage and one with. Then take comparison shots under desired conditions.

However, that would only give results which hold true for that lens and that damage. Vary the lens or the damage and repeat?

All in all, perhaps not possible to generalise?

[Laurentiu Cristofor]