Andrew Brydon wrote:
> Been recommended both UV filter and Polarising filter, both as
> alternatives for a semi-permanent attachment when outdoors.
> What are the pros and cons of each, and overall which would be the
> better choice? [Local shop only has circular polarisers, if it
> matters.]
Polarizing filters should NOT be used on a regular bases. They make
changes to the recorded image that you may or may not like. They also
reduce the total amount of light reaching the sensor by a significant
amount. They are the filter I would consider the most useful to the digital
photographer as you can't reproduce the effect after the exposure, but you
don't want them all the time. Circular polarizers are required for some
cameras to assure the automatic systems work properly.
UV filters filter out UV and, depending on the filter, some visible
light in the blue range. Based on what I have been told and from my own
quick experiments, digital cameras by nature have very little if any
sensitivity to UV light.
Most people who own UV filters have little or no idea what they really
do. They use them not for their filtering effect, but because the want to
"protect" the lens.
In the real world, very little reduction in image quality will be caused
by the additional glass. UV filters are easier to find and cheaper than
plain glass.
Also in the real world there is very little to fear from meaningful
accidental damage to a lens under normal situations. A small scratch or
nick on a lens really does almost nothing to the capabilities of the lens.
While there may be some loss of resale value due to a scratch, with
digitals, even a two year old camera is so far out of date that resale value
is not a real issue. SLR's with interchangeable cameras are an exception
I would have to say that much more is paid for UV filters every year,
than value lost by scratches etc.
In short, if it makes you feel good to use one, do it and don't feel
bad, if it makes you feel good not to use one, then don't and don't worry.
Personally I don't wear suspenders and a belt, I often don't even wear
either.
--
Joseph E. Meehan
26 + 6 = 1 It's Irish Math