mj wrote:
You pays your money and you takes your choices.

For better than 20 years I serviced both 35mm and most medium format
systems. I can say that in a small percentage of all the lenses I have
repaired (less then 20%) I have seen "protection" filters break into the
front element of the lens scratching it. Hoods generally offer better impact
protection. IMO


You need very careful to understand the implications of that statistic.

As a lens repair person you say you see 20% of lenses where the filter
has damaged the lens. I don't dispute that at all. But it does *not*
mean that 20% of the lenses which have UV filters suffer such damage.
Most people, who damage their filters will do it in a far less
catastropic manner. They are likely to put a scratch on the filter,
replace the filter and not send the lens for repair.

Also, whilst I accept filters can damage the lens if hit sufficiently
hard, one would have to question whether the lens would have been
damaged anyway without the filter. If a knock is sufficient to damage a
filter and smash it into a lens, it must have taken quite a knock -
quite possibly enough to have damaged the lens anyway.

I personally tend to use filters all the time. I might make an exception
on my Nikon macro lens though. The front element is very well recessed,
making damage to the element unlikely. Whilst I have never proved this,
I suspect a filter is more likely to degrade an image if the object is
focused very close, which is what one is likely to do on a macro lens.

But since the element on the micro nikkor lens is very well recessed, it
will be difficult to clean, so perhaps there is a good reason to buy a
UV filter.

Scratches on lens elements have a very significant effect on resale
value. There is for example a Nikon 600 mm lens for sale:

http://cgi.ebay.com/ws/eBayISAPI.dll...m=220278589593

This would be perfect for me.

* Just the lens I am looking for.
* Seller is only 40 miles away.
* Seller happy for me to pick it up.
* I can avoid the very significant risks of Paypal on items over $2000.

But that 600mm lens has a small scratch on the front element, and is a
bit tatty in places. Whilst I did bid, I am not going to bid again. It
has reached $4900 which I feel is enough for a lens with a scratch on
it. Had the condition been better, I would certainly have bid a lot
more, especially as it is very local to me.



I would rather see an auction where the seller says "has had a UV filter
on from day one" than "has a small scratch but does not degrade image".
Clearly scratches are more likely to cause problems when shooting into
the light.