Ordered a roxsen focal reducer and it just came a few days ago, dissapointed with center sharpness.

Discussion in 'Adapted Lenses' started by colbycheese, Jun 21, 2015.

  1. colbycheese

    colbycheese Mu-43 Veteran

    378
    May 1, 2012
    Way up there.
    So a few weeks ago i ordered the roxsen focal reducer (EOS-M4/3) and it arrived a few days ago. I did some tests with my Nikon E Series 50mm and did a center crop comparison. I am kinda disappointed with the results the focal reducer is giving me. I looked at a ton of tests that people did with this focal reducer and the center sharpness really didnt seem to be that much different. Anyways here is the comparison photos if any wants to see. The camera wasnt moved at all at both shots used f/4 (the f-stop was set to 4 on the lens for both. I used base iso for both as well. No post processing done except cropping.
    Without the focal reducer
    https://www.flickr.com/photos/97949387@N05/shares/m200m9
    with the focal reducer
    https://www.flickr.com/photos/97949387@N05/shares/7UGC2S

    It seems not only sharpness is reduced but a blue tinge is present. I know about the shooting towards lights can cause blue spots problem but this was shot with lights only behind the camera. Anyways does anyone know if this is normal or should i get a refund? Thank you
     
  2. Klorenzo

    Klorenzo Mu-43 All-Pro

    Mar 10, 2014
    Lorenzo
    Try with a fixed white balance. And the second one looks overexposed. I'd try to match the exposure as much as possible.
     
  3. HarryS

    HarryS Mu-43 Top Veteran

    921
    Jun 23, 2012
    Midwest, USA
    I compared them in Lightroom and all I can say is they must be small crops as it's pretty jaggy at 4:1. Don't see much difference either,
     
  4. RnR

    RnR Mu-43 All-Pro

    Sep 25, 2011
    Brisbane, Australia
    Hasse
    Umm... why are you fixing the position of the camera in place? The focal reducer makes your 50mm into a ~75mm'ish vs the normal 100mm. Would you do a sharpness test between a 35mm lens and a 50mm lens by shooting from the same spot? Shoot such that the scene looks the same without you having to crop. Otherwise its impossible to gauge the effect of the focal reducer.
     
  5. bikerhiker

    bikerhiker Mu-43 All-Pro

    Dec 24, 2013
    Canada
    David
    Colbycheese, I posted my thoughts with my Mitakon Lens Turbo (one of the better cheaper focal reducers) which you can search for it on this forum and it produced great sharp results. I also get a blue spot and orange flare under direct light; but you shouldn't get any color tinge on yours? It also looked kind of out of focus too. The problem I found with my Mitakon is that, there is some play with the mount and if you use focus peaking, the focus will always be just off slightly. If you shoot say @ f/5.6 and f/8, DOF will be wide enough to cover any manual focus error. Use focus magnify 7x or 10x to assist in nailing focus and make sure you shoot from the tripod. You will have better results. If not, then check IBIS and dial in the correct focal length. If you did everything possible and still not getting the results, then it's possible you have a defective focal reducer.