Prime M/F vs Prime auto focus?

Discussion in '35mm Cameras and Accessories' started by stradibarrius, Aug 22, 2013.

  1. stradibarrius

    stradibarrius Member

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    I was wondering if there is a result difference between a prime M/F and Autofocus from the same manufacture. Of course I am talking about equal quality, era, vintage etc. lenses.
    I have never really thought about this until now.
    Not looking to start a war just looking for opinions.
     
  2. BMbikerider

    BMbikerider Member

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    I don't actually think there will be a great deal of difference. I have used both types of Nikon AIS manual and AF 20mm and 28/85 AIS and AF and apart from the build quality on the AIS versions being a shed load better there was no difference in the image quality. In comparison the AF versions seemed to be quite flimsy.
     
  3. markbarendt

    markbarendt Subscriber

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  4. Dr Croubie

    Dr Croubie Member

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    The experiences I've had with Canon are that the glass has gotten better, the build quality went down but has since gone back up.
    Example: going from FD to EF was in the 80s, when plastic was fantastic. My FL 55/1.2 is a great metal beast, optically great except some wide-open coma (gone by f/2). My EF 50/1.8 II is a toy. They even used to make the EF 50/1.8 (mk1) with a metal mount, then changed it to plastic to save a few bucks. Optically, I can't compare it to the FL55/1.2, but from what I've seen it's not that much different to the FD 50/1.8. They've had problems introducing lenses with new optical formulae, eg their first versions of their digital lenses were shocking, and their cameras got a bad rap because their kit lenses were so bad, ie 18-55mk1. But lately they've gotten a lot better, even for the price, my 40/2.8 pancake is great, you can get them for $150 nowadays, and mine spends its life glued to my EOS3 with an orange filter on the front, damn fine lens.

    When Mamiya 645 transitioned to AF they also kept the same glass, just re-mounted them in an autofocus barrel and added an electronic diaphragm. I recently tried getting a 45AF to replace my 45MF. Glass was good, but the diaphragm was DOA, wouldn't stop down or open up, which is kinda useless, so I had to return it. Build quality looked a bit more plasticy compared to the MF tank, which probably contributed to it breaking easier, but the glass was the same. (They've recently re-formulated a lot of their lenses to make them work better with digital, but that's not directly related to being AF).


    I have heard things about Nikons, especially the 20mm primes (that I was looking at getting once), in that the first ones were a lot different to the second ones, some were sharper in the centre as a trade-off for more distortion or softer corners, can't remember which was which though...
     
  5. flatulent1

    flatulent1 Subscriber

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    I assume you're talking about the effect of autofocus on image quality? That'd depend entirely on the user. Someone focusing manually is usually more careful about focusing precisely where he wants, while someone relying on autofocus may or may not hit it and may not notice until he gets the images back. Gross generalities, to be sure, but certainly true from my own experience.

    If, on the other hand, you're talking about, say, the optical difference between the FD 85mm f/1.2L and the EF 85mm f/1.2L, there is no difference from what I've heard. But if you look at another pair like the FD 24mm f/1.4L and the EF 24mm f/1.4L, there may well have been optical improvements incorporated in the new lens.
     
  6. kitanikon

    kitanikon Member

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    Numerous differences could have been introduced....structurally as mentioned already, but also in terms of HOW it focuses...

    MF lenses typically are viscous dampened for a more "fluid" feel (an exception I've noticed is the 60mm/2.8 AFD micro-Nikkor that is quite smooth for an AF lens, and the full time MF/AF Canon EF lenses are okay for MF)
    ...whereas AF lenses generally must be 'fluid-free' for quicker turning using the motor (in-camera or in-lens).....

    As for actual practical usefulness...
    MF is better (for me at least) when shooting in dense woods/forest where the AF is easily "confused" by leaves, branches and such...and I can focus more quickly since I know where I want to focus...