How to rate a lens?

Discussion in 'Adapted Lenses' started by alaios, Dec 13, 2013.

  1. alaios

    alaios TalkEmount All-Pro

    Jan 11, 2013
    Real Name:
    Hi all,
    I just got a lens and the pics I got look okay to my mind. I was wondering though how I can test how "sharp" it is.

  2. Amamba

    Amamba TalkEmount All-Pro

    Apr 13, 2013
    SE MI
    Take shots of something sharp and contrasty, like printed text.

    Use a tripod, or direct flash to minimize camera shake (flash can cause lack of contrast due to reflected light, so be careful).

    Sent from my Nexus 7 using Tapatalk
  3. Poki

    Poki TalkEmount Hall of Famer

    Aug 30, 2011
    You don't really need to test a lens separately, just look at the pictures you've taken at 100% magnification. If they look okay to you at every part of the image, the lens is good enough.
  4. f/otographer

    f/otographer TalkEmount Regular

    Aug 20, 2013
    I would recommend instead of spending time trying to figure out something so ephemeral as "how sharp is this lens", which is very subjective and open ended depending on the conditions involved in trying to figure this out (and useless anyway), the time would be better spent just going out into the world and use the lens to create art.

    You will find out nothing useful about a lens by shooting brick walls or (forgive me Amamba) shooting text or rulers or grid lines. What an absolute waste of a photographers time.

    Rather you will find out everything about a lens by simply using it to take photographs. Shoot your family members, shoot your pets or your children, walk down a street and shoot interesting architecture, or passers by, or a shadow dappled store front, or a tired mother pushing a baby stroller, or a stray dog sniffing trash cans in an alley, or a passing locomotive, or an empty train bridge, or a flower, or a chained up bicycle, or an airplane overhead, or sun thru tree leaves, or a spider, or kids playing ball, or your reflection in a window, or a statue in a park, or a stream, or....


    One of the above scenarios is going to give you a bunch useless photos. One scenario can give you art. After you have made Art with a lens (or even just tried to make it) you will begin to understand its character, its innate nature. You will begin to understand how it sees the world, how it reacts to changing light. Even how it reacts to the movement of the human soul.

    How to rate a lens? You rate it by the great photographs it takes. Which is, incidentally, how you rate the photographer.
    • Like Like x 6
  5. quezra

    quezra TalkEmount Top Veteran

    Aug 22, 2012
    I agree generally with what the others have said, but I do still think there is use in testing a lens, particularly at different f/stops to get a feel of its character. Many old legacy lenses change quite dramatically between wide open and stopped down a little bit, and understanding this characteristic can help you compose when you have room to play with aperture (i.e. you don't need it fully open or fully stopped down). No need for lens charts, but set a lens on a tripod with a range of stuff more or less in the focal plane and shoot at different f/stops to get a sense of how the bokeh, corners, etc shift. And some lenses just aren't really worth shooting wide open - good to know that too, especially finding your favorite apertures to capture the 'character' of the lens.
    • Like Like x 1
  6. Poki

    Poki TalkEmount Hall of Famer

    Aug 30, 2011
    This reminds me pf LOTR: Swords get their names for the things they did in combat. I guess it's the same for lenses. ;)
    • Like Like x 2
  7. f/otographer

    f/otographer TalkEmount Regular

    Aug 20, 2013
    Thats exactly right. I personally own Lightbender, The Shutter Hammer and Diffraction Biter, all made by the Elven smith Tomioka.
    • Like Like x 6
  8. xXx1

    xXx1 TalkEmount All-Pro

    Jan 15, 2013
    There is one good reason to photograph brick walls and it is to test if the lens is "decentered". Pixel peeping gives enough info about the quality of lens but one needs to take care not to go too far as there is seldom need to go into extreme print sizes.

    It is bacically like or dislike type of thing.
  9. addieleman

    addieleman Passionate amateur

    Nov 13, 2012
    Real Name:
    Ad Dieleman
    I do both types of lens evaluation actually: I first make a few test shots to see if it has any objectionable flaws. This is sort of an intake; many lenses in my collection don't get past this point. If I like what I see, I'll take it on a test drive making "real" pictures. I only know after months of use if I really like a lens and what it does for me, not being a prolific photographer (alas!). And it happens that after a few times in actual use I dismiss a lens after all, because there's something I don't like. Most prominent example in my case is the Zeiss Distagon 28/2.8 for Contax/Yashica, a really sharp and contrasty lens, but I didn't like its inky black shadows and cool color rendition. So out it went after its first test drive although it was the sharpest 28mm lens I have ever seen.
  10. Gandalf

    Gandalf TalkEmount Regular

    Sep 5, 2013
    Right on! A good way to get to know a new lens -- or a lens you haven't used for a while -- is by spending a day shooting ONLY with that lens, just leave all the rest at home. If you find a subject you'd prefer to shoot with a different lens, shoot it anyhow and spend some extra time on it. At day's end you'll know how the lens performs and how you'll be able to get your best results with it.