Filter Quality Specs

[MBehrens]

I see suggestions on filters in the forum and the only guideline that is ever provided in choosing a quality filter is to "don't go cheap" not really very helpful.

What has prompted this is that I recently had a lens in to the manufacturer for front-focus calibration. Their first question was "are you using a UV filter?" Of course no mantra seems to be more agreed upon than using a protective filter. The next question from the rep is "is it a quality filter?" my response is I didn't buy the most expensive, but not the cheapest either. His response was that cost didn't indicate quality... So what does? He could not elaborate. Can anyone here elaborate?

I'm currently shopping for some ND filters and find myself stalling out on how to choose.

Thanks.

[ErikKaffehr]

Hi!

My guess is that filter quality does not matter so long as it's decent quality and multicoated. Resolution may be affected by filters but this may be more related to thickness than to quality. I would be much surprised if any decent filter would affect front or back focusing.

Best regards
Erik

I see suggestions on filters in the forum and the only guideline that is ever provided in choosing a quality filter is to "don't go cheap" not really very helpful.

What has prompted this is that I recently had a lens in to the manufacturer for front-focus calibration. Their first question was "are you using a UV filter?" Of course no mantra seems to be more agreed upon than using a protective filter. The next question from the rep is "is it a quality filter?" my response is I didn't buy the most expensive, but not the cheapest either. His response was that cost didn't indicate quality... So what does? He could not elaborate. Can anyone here elaborate?

I'm currently shopping for some ND filters and find myself stalling out on how to choose.

Thanks.

[250swb]

I agree that any expensively good filter should not affect focusing ability. But there are some top filters that are better than others IMO, like the B&W MRC range, although this is not just based on theoretical optical performance, but on aspects like easy cleaning, brass rings, and thinness.

Steve

[situgrrl]

Their first question was "are you using a UV filter?" Of course no mantra seems to be more agreed upon than using a protective filter.

Really?  Not here I don't think!  I don't use them except when I'm by the sea or in the mountains.  Unnecessary glass results in lower quality.  FWIW I use Hoya Pro MC filters - though the same glass is repacked as Kenro now for less money.

For ND filters however, I use Cokin P.  They are resin and not the best optically - though acceptable for video which is what I use them for.  There is a nice set of Cokin X Pros in the second hand section I suspect are a better optically.  Square holders make grads much easier to use.

[MBehrens]

Thanks.