Hoya R72 IR Filter Flare & Lens Hoods

Discussion in 'Open Discussion' started by tradesmith45, Jun 21, 2013.

  1. tradesmith45

    tradesmith45 Mu-43 All-Pro

    Dec 13, 2012
    Oregon
    Hi all,

    Been shooting IR w/ my new OM-D for a bit & loving it. Bought the ever popular Hoya R72. Hands down it produces the most flare of any filter I've or did own. Did lots of testing w/ 3 lenses & other filters - its defiantly the Hoya. And we are not talking about a little icicle of flare but rather a giant lolly pop.

    The B&H web site where I got the filter is completely mute about anti-reflection coating on this & all the other IR pass filters.

    So do any of you folks have experience w/ other IR filters w/ no/little flare? That you are sure have AF coatings?

    Testing revealed lots about my lenses & various hoods. I'll post more on hoods later. The factory hoods provide very little shade for the filter. If the Hoya is at least 35% shaded, flare mostly goes away. The worst problems are naturally on the widest angle lenses - my M.Z9-18mm. Zooms are as expected worse than primes. With the 12mm, I can have the sun in the frame & have almost no flare. Until I screw on the R72.

    I did a search on this site for other comments about this & found lots of discussion about lens hot spots w/ IR. Surprise, when the filter was described they were all - you guessed it - the Hoya R72.

    Thanks much!
     
  2. usayit

    usayit Mu-43 Hall of Famer

    Hot spots are usually the result of the lens' characteristics not the IR filter....

    I have an IR filter that works wonderfully across the lenses that I like to use for IR. My newest lens, Leica 35mm f/1.4 Summilux Asph, is regarded as one of the best optics available YET... IR hot spot is terrible right in the center of frame. Totally useless in IR.
     
  3. usayit

    usayit Mu-43 Hall of Famer

  4. tradesmith45

    tradesmith45 Mu-43 All-Pro

    Dec 13, 2012
    Oregon
    What IR filter are you using?

    Thanks much for the link. But it shows the 3 lenses I tested on - M.Z 9-18, 12 & 14-42 IIR - are rated as good IR performers.

    Based on my tests & observations, I'm now a skeptic on the issue of IR hot spots - lens or filter. There certainly could be a problem w/ some lenses but I now think 2 other factors may be even more important - hoods & filters.

    First is the universal inadequacy of factory lens shades. More on this later but the short version is every shade I have ever owned is much too short & the Mu43 stuff is the worst. They seemed designed for compactness rather than shading. I routinely look for a shade made for the next longer FL lens to get effective hoods. That has never resulted in a hood that vignettes. But there are much fewer choices for Mu43 especially for the 9-18.

    Flare from the R72 is super sensitive to shading as I reported. So we can safely assume that all the tests reported on the link you sent have been made w/ inadequate lens shades.

    My OM-D is unmodified. The R72 lets in some visible & the camera blocking filter cuts off most long IR. The camera/lens is already seeing the same wavelengths. We should be seeing lots of flare & hot spots in the visible images but lower intensity. In my tests, nothing even close shows up in the regular shots w/ a UV filter that has strong AR coatings.

    Now IR PP nearly always includes cranking up contrast & clarity/definition to the max. That will certainly reveal lens flaws not seen in visible shots w/ weaker PP adjustments. With good shading of the R72 & w/ the UV filter, I can crank up PP w/o any hot spots & little/no flare depending on the lens.

    So I'm suspecting that the other problem is inadequate AR coating on the IR filters.
     
  5. tradesmith45

    tradesmith45 Mu-43 All-Pro

    Dec 13, 2012
    Oregon
    By the way usayit, please excuse my strident tone above. I'm pretty steamed about spending so much $$ on filters & hoods that don't work so well.

    You're post is greatly appreciated!
     
  6. tradesmith45

    tradesmith45 Mu-43 All-Pro

    Dec 13, 2012
    Oregon
  7. tradesmith45

    tradesmith45 Mu-43 All-Pro

    Dec 13, 2012
    Oregon
    You won't be surprised to have me suggest you try a hood for a 50mm or longer on this lens. In my film days, I always rummaged through camera store parts bins for good hoods. Now you can find many options on ebay.
     
  8. usayit

    usayit Mu-43 Hall of Famer

    Giottos IR filter 092. I only do IR (on an M8) occasionally so I simply didn't go for the highest quality filter (I usually do with other filters). I would say its comparable to the Hoya. I can't go stronger without modifications to the camera.

    Samples

    5910027161_f9d87a3c5c_b.

    5909840153_f5558748a0_b.

    5929950484_4f3c31f2c8_b.

    My filter is a 77mm size and I use step up filters to affix them to whatever lens thread size. As such, none of my shots with filters have hoods attached. As for hoods (in general), my observation is that they are only effective on the widest focal length on zooms. Kinda make sense as the FOV is variable and a completely effective hood would also need to be adjusted as the FOV changes. I am mostly a prime shooter. Generally, I use 12mm Heliar and a 24mm Elmarit for IR.
     
  9. usayit

    usayit Mu-43 Hall of Famer

    My test IR shots with the 35mm were also done from a shaded view point with the same hot spot of about 30% of the frame dead center. The same occurs no matter the conditions. No matter... the lens was never intended for IR...
     
  10. tradesmith45

    tradesmith45 Mu-43 All-Pro

    Dec 13, 2012
    Oregon
    Nice shots!

    I chose the Hoya R72 based on cost just as you did. I've contacted B&H to see if they can demonstrate any advantage for the hi priced stuff.

    You'll find lots of cheap 77mm hoods out there on ebay. A folding rubber one might work for the 35mm.