Updated 23/06/08 Hot on the heals of Sabbath999's thread http://www.thephotoforum.com/forum/showthread.php?t=100141 where he showed the nastyness of the Hoya HMC UV(0) filter on his 70-200 f/2.8, it got me thinking about sthe quality of my filters. Fortunately I have one of every filter Hoya makes with exception of their snake oil based "digital Pro1" filter which they can shov... Anyway so I decided to do a test of not only sharpness but also flare issues. Unfortunately my Hoya HMC is on a lens which I left at a friends. But fortunately Sabbath999 already covered that filter in his thread linked above, and I still have a Hoya standard and a Hoya SuperHMC filter to play with. Unfortunately they all go on different lenses So: Assumptions and Method: All photos were taken on a tripod with mirror lockup. All photos were taken at the maximum sharpness of each lens, determined to be f/5.6 on the Nikkor 80-200mm f/2.8 at 80mm, and also f/5.6 on the Nikkor 18-70mm f/3.5-5.6 at 18mm. The 18-70mm is less sharp giving the Hoya standard filter a bit of an advantage seeing how poor quality would be harder to see. Nevertheless the results are still rather conclusive. Sharpness photos were taken outside in the sun photographing gravel. The lens hood was on, and the camera was in the shade to prevent the results being biased by light hitting the element. Contrast photos were taken inside against a black bed photographing into a wirelessly triggered SB-800 set to 1/64th power. Results: Hoya Pro1D Protector Sharpness 80-200mm f/2.8 @ 80mm f/5.6: No filter VS Filter: Hoya SuperHMC UV(0) Sharpness 80-200mm f/2.8 @ 80mm f/5.6: No filter VS Filter: Hoya Standard UV(0) Sharpness 18-70mm f/3.5-5.6 @ 18mm f/5.6: No filter VS filter: Hoya Pro1D Protector Contrast 80-200mm f/2.8 @ 80mm f/5.6: No filter VS Filter: Hoya SuperHMC UV(0) Contrast 80-200mm f/2.8 @ 80mm f/5.6: No filter VS filter: Hoya Standard UV(0) Contrast 18-70mm f/3.5-5.6 @ 18mm f/5.6: No filter VS filter: Conclusion: Well as can be seen the Hoya Standard filter shows a visible difference even on a standard kit lens. This is the cheapest in Hoya's lineup and has no coating on the glass. You can easily see your own reflection when looking into the lens. This of course causes it's massive flare problems too, extending all the way to a loss of contrast. I won't be buying this filter again. The Hoya HMC filter is absent from this test but Sabbath999 showed it makes a visible difference with a very good lens. How this filter would affect a cheap kit lens is unknown. The MultiCoat on the glass would also give it better contrast and flare performance than the Hoya Standard filter too but this is as yet un tested. The Hoya SuperHMC is the cheapest in their professional lineup that comes in a black case with gold writing so it must be good right? Well it worked pretty well. Sharpness wise there doesn't appear to be a problem and the 80-200mm f/2.8 is a very sharp lens to begin with. I have no reservations about keeping this on my lens all the time. The contrast is excellent and there is no visible flare. There is a ghosting artefact, which would still mean removing the filter when shooting into the sun or other light source. They are also cheaper than B+W filters so I think I'll only be buying this type from this point forward. New filter The Hoya Pro1D is the flagship filter in the Hoya lineup and comes at a flagship price. This filter is unfortunately the result of much marketing fluff and as can be seen above hows no improvement over the SHMC results. That didn't stop the filter from costing significantly more. It still ghosts, while controlling flare worse than the SHMC did. How did I reach this conclusion? The colour of the flare has moved up towards the green part of the spectrum. Ideally the closer to UV the further it should be from the visible spectrum and the better. Please note compared to the other tests the exposure is slightly lower. Sharpness wise this filter is also fine, but again no improvement over the cheaper SHMC. What is really saddening is the website. While the SHMC section at least had the decency to show some graphs, data, and give actual information, the Pro1D section is full of lovely big colourful graphics claiming superior performance suited to digital cameras (like this makes a difference), along with other fancy details like thinner glass (sounds more fragile), a black matte internal frame to reduce inner glass reflection (what?, but my Hoya standard filter fell apart the other day and had a black matte frame too), and no data or explanation of why this is good at all. The only benefit is the frame is about 0.8mm thinner which may help if you suffer from vignetting with thicker filters like polarisers. Overall I can not recommend this filter given its increased price over the Hoya SHMC.