Panasonic Leica 15mm real minimum focusing distance.

Discussion in 'Native Lenses' started by TheWintermute, Aug 9, 2017.

  1. TheWintermute

    TheWintermute New to Mu-43

    6
    Jan 9, 2017
    Hi owners of Panasonic 15mm lens,

    I'm currently contemplating switching my 17mm Olympus for 15mm Panasonic to obtain a slightly larger view angle. One of the important characteristics for me is close-up capability.
    On paper Panasonic has 20cm closest focusing distance and 0.1x reproduction ratio.
    And Olympus has 25cm closest focusing distance and 0.08x reproduction ratio.

    However, I found that on practice the Olympus is actually capable of focusing on objects just 17cm away from the focal plane. Therefore it actually provides a reproduction ratio of 0.12x.
    I measured reproduction ratio by taking photo of a ruler and dividing sensor width (17.3mm) by the length of the ruler in the frame (140mm).

    Can someone with a 15mm Panasonic measure the ACTUAL closest focusing distance from the focal plane OR just take a picture of a ruler for me at the closest possible distance?

    Thanks!
    P1060522-3.
     
  2. jyc860923

    jyc860923 Mu-43 Hall of Famer Subscribing Member

    Feb 28, 2012
    Shenyang, China
    贾一川
    Not that I own the PL15, but for some lenses the actual FL shrinks when focusing close, which I think is called focus breathing, it's not accurate if you just calacutate the magnification ratio based on manufacture's claimed FL, if Olympus says the magnification of the 25mm is 0.08x, it means the actual FL in closest focusing distance must be shorter than you interpreted based on which your calculation suggested a magnification of 0.12x.

    Now if someone has a photo of a ruler I'm interested too.
     
  3. TheWintermute

    TheWintermute New to Mu-43

    6
    Jan 9, 2017
    Hi! I believe that taking a picture of a ruler is a foolproof way of measuring magnification which doesn't depend on focal length, focus breathing or anything else. It's literally just saying that at the minimum focusing distance the object of length X will fill the frame completely, therefore the magnification = sensor_size/X by definition of magnification.

    Cheers
     
    • Agree Agree x 2
  4. jyc860923

    jyc860923 Mu-43 Hall of Famer Subscribing Member

    Feb 28, 2012
    Shenyang, China
    贾一川
    yes taking a photo of the ruler is the ultimate way.

    your ruler photo shows that the magnification is 1.226950... what's Olympus thinking???
     
  5. Mike Wingate

    Mike Wingate Mu-43 Top Veteran

    558
    Feb 21, 2017
    Altrincham
    Mike Wingate
    image. image. Photo of a rule. A Ruler is someone who sits on a throne, for example Queen Elizabeth II.
    5". Manual focussing with the PL15mm until the blue focus peaking lit up the length of the rule. GX80.
     
    • Funny Funny x 1
  6. Mike Wingate

    Mike Wingate Mu-43 Top Veteran

    558
    Feb 21, 2017
    Altrincham
    Mike Wingate
    124mm or 5" closest focussing distance.
     
  7. b_rubenstein

    b_rubenstein Mu-43 All-Pro

    Mar 20, 2012
    Melbourne, FL
    We have a more definitions on this side of the pond: Definition of RULER
     
  8. Mike Wingate

    Mike Wingate Mu-43 Top Veteran

    558
    Feb 21, 2017
    Altrincham
    Mike Wingate
    Totally copacetic with that.
     
  9. TheWintermute

    TheWintermute New to Mu-43

    6
    Jan 9, 2017
    Thanks very much for the pictures!
    If 124mm fills the frame, it means Panasonic 15mm has maximum magnification 0.14x. Much better than advertised and better than Olympus 17mm.
    This is another reason to switch for me.
     
  10. Mike Wingate

    Mike Wingate Mu-43 Top Veteran

    558
    Feb 21, 2017
    Altrincham
    Mike Wingate
    No problem. I generally mount the camera on a rack and pinion and just move it forwards and backwards to focus. With this lens in manual, it was so fast and easy and the blue peaking really worked well. Which is a feature I found when borrowing one in Manchester.
     
  11. MillsArt

    MillsArt Mu-43 Regular

    94
    Jul 8, 2012
    Wouldn't something like one of the various true macro lenses, or the 45/1.7 etc be a better lens for getting as much magnification as possible ?
     
  12. Not if you're after a 15mm perspective...