This site is supported by the advertisements on it, please disable your AdBlocker so we can continue to provide you with the quality content you expect.

Explain this!

Discussion in 'Adapted Lens Forum' started by hectorlektor, Sep 12, 2017.

  1. hectorlektor

    hectorlektor Premium Member

    Joined:
    Sep 25, 2014
    Messages:
    228
    Likes Received:
    136
    Location:
    Sweden

    -Return to Top-

    So I own the Samyang 100mm 2.8 macro for Nikon, and I have used it on both Sony and Fuji and Nikon. However, it always seem to be sharper on the Nikon camera for some reason, not by much, but noticable. I have tried several copies of my friends lenses and came to the same results. However when I tried several copies of the lens made for Sony FE and Fuji X they were as sharp as the Nikon was on the Nikon body, no matter what the resolution of the sensor. I mean, the only difference what I know of is that the FE mount and X mount have built in adapters in the lens barrel. Can it be that the adapters are taking away some sharpness? But that would be weird since they don't contain any glass, and if they were faulty they would have messed with infinity focus or something like that.

    Anyone who can explain this?
     
  2. robert

    robert Administrator Staff Member

    Joined:
    Feb 21, 2011
    Messages:
    15,362
    Likes Received:
    4,987
    Location:
    Austin

    -Return to Top-

    The only thing an adapter is doing is putting the lens in the proper position for the sensor. Even if the adapter is slightly 'off' the only thing that can be affected is the close focusing distance or the infinity focusing distance.

    How are focusing with the Nikon, and which Nikon body are you using?
     
  3. lawsofphysics

    lawsofphysics Premium Member

    Joined:
    Apr 17, 2013
    Messages:
    2,407
    Likes Received:
    881
    Location:
    usa

    -Return to Top-

    Ad hoc testing can be confusing and frustrating.
     
    AnthonyM likes this.
  4. hectorlektor

    hectorlektor Premium Member

    Joined:
    Sep 25, 2014
    Messages:
    228
    Likes Received:
    136
    Location:
    Sweden

    -Return to Top-

    Focusing isn't any problem with any body or any adapter, both close and infinitu focusing is just fine for all lenses and all bodies and all adapters. That why it's so strange, how can it be sharper on my d800e than my A7, A7rii, Xt 20, xe1, xe2, my friends a7ii and a7r, it doesn't make sense. Am I being haunted by the unsharp ghost???? :eek: :D :D :D
     
  5. robert

    robert Administrator Staff Member

    Joined:
    Feb 21, 2011
    Messages:
    15,362
    Likes Received:
    4,987
    Location:
    Austin

    -Return to Top-

    You didn't answer the question. How are you focusing? Are you using the focusing screen or the green LED focus assist?

    Are you doing side-by-side controlled testing with all these cameras using a tripod, or are these taken at different times in different conditions hand-held?
     
  6. hectorlektor

    hectorlektor Premium Member

    Joined:
    Sep 25, 2014
    Messages:
    228
    Likes Received:
    136
    Location:
    Sweden

    -Return to Top-

    I tried it indoors with both focusing aids and no focusing aids, green dot, just my eyes, peaking and so on. Makes no difference.
     
  7. dem

    dem Premium Member

    Joined:
    May 31, 2015
    Messages:
    627
    Likes Received:
    309
    Location:
    UK

    -Return to Top-

    Are you comparing image sharpness for a full frame Nikon and a full frame Sony to an APS-C Fuji using the same Samyang 100/2.8 designed for a full frame?

    How are you making this comparison?
     
  8. robert

    robert Administrator Staff Member

    Joined:
    Feb 21, 2011
    Messages:
    15,362
    Likes Received:
    4,987
    Location:
    Austin

    -Return to Top-

    Unless you do controlled tests, any results are anecdotal and meaningless.
     
  9. Goldingd

    Goldingd Premium Member

    Joined:
    Jan 20, 2014
    Messages:
    641
    Likes Received:
    160
    Location:
    Anaheim CA

    -Return to Top-

    If you can look thru the back of both lenses, is anything going on different in the rear element? Slightly different rear element???

    Your Nikon mount copy was probably designed with a full frame focus circle, and DSLR flange depth in mind. The FujiFilm mount version, in addition to having a bit longer rear section to account for the mirrorless shorter flange depth, and of course the attachment ring appropriate to a Fuji X mount, may have also had a bit of lens element design modification as so to create a nice flat area of focus at the sensor. Or, thy could of just attached a different rear cylinder keeping all the actual part with the elements the same.
     
    Last edited: Sep 12, 2017
  10. Frankie

    Frankie Premium Member

    Joined:
    Mar 31, 2011
    Messages:
    3,389
    Likes Received:
    559
    Location:
    The Left Coast

    -Return to Top-

    As I'd posted in another recent thread: "......sharpness is a pleasing combination of resolution and contrast."

    Perhaps your camera sensor/FW is better in resolution and/or contrast?
     
    beakhammer likes this.
  11. beakhammer

    beakhammer Premium Member

    Joined:
    Oct 5, 2013
    Messages:
    10,170
    Likes Received:
    6,284
    Location:
    Salish Sea

    -Return to Top-

    I have often found that different lenses perform better or worse on different cameras. Much of what we perceive as sharpness is a hodgepodge of effects such as contrast and resolution and color fringing and so forth, all of which are impacted by the lens, the sensor, the processor, the lighting, the aperture, the shutter speed/mechanical vibration, filters, lens-hoods, the nature of the subject, the post-processing software and the photographers own opinions and eye-sight. This goulash of complex factors means that some lenses seem to work better with some cameras than with others. That's just the way it is, and it's one reason why I own so many lenses.
     
    Goldingd likes this.
  12. gyoung

    gyoung Premium Member

    Joined:
    Oct 3, 2013
    Messages:
    365
    Likes Received:
    108
    Location:
    Nottingham

    -Return to Top-

    I seriously doubt there is any optical tweaking going on, just mount difference, this is a 'budget' brand!
    Differences can arise from sensor design, anti aiiasing filters etc, but in general, having used a lot of mf lenses on Nikon, Sony and Fuji, its mote likely 'pilot error' than optical or mechanical.

    Gerry
     
  13. robert

    robert Administrator Staff Member

    Joined:
    Feb 21, 2011
    Messages:
    15,362
    Likes Received:
    4,987
    Location:
    Austin

    -Return to Top-

    We are being asked to explain an anecdotal situation without any examples.

    Do some controlled tests and get back to us with the viewable results, then we'd be happy to Explain!

    :bling:
     
    gyoung and beakhammer like this.
  14. magmouse

    magmouse Premium Member

    Joined:
    Jul 19, 2015
    Messages:
    680
    Likes Received:
    1,069
    Location:
    London, UK

    -Return to Top-

    What Robert said...

    Plus, in designing your tests, you'll need to think about how you accommodate the different crop factors. APSC uses a smaller part of the image circle, and so (all other things being equal) magnifies the optical image created by the lens more than a full-frame sensor. This means that the softness of edge transitions in the image that create the impression of more or less sharpness are also magnified.

    Of course, making all things equal can be borderline-impossible, as @beakhammer points out...
     
    beakhammer likes this.
  15. pfogle

    pfogle Puzzled

    Joined:
    Nov 20, 2013
    Messages:
    1,344
    Likes Received:
    949
    Location:
    Auckland New Zealand

    -Return to Top-

    Just use the combo that works! Why sweat it?
     
    Fujiphotog likes this.

Share This Page