Is there any loss of IQ when using a UV filter.

The best way to answer this question is with your own eyes. Set your camera on a tripod ane shoot a test with and without your UV filter. Make sure you have consistent light so you not confusing your test results with lighting changes. Look At the images at about 50% magnification and make up your own mind.

One thing you will discover here on the forum is that there are two equally divided camps, yes... and  no...

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Phil
www.PhilCorlis.com
www.FindingBritain.com