• #387
    David K

    How are guys finding the AF on the S2 lenses. Is this an individual lens thing or a camera thing?

  • #389
    woodyspedden

    for the most part I find AF to be pretty good. Not in the Nikon class but pretty good. My 120mm sometimes gets into a hunt mode when focusing towards infinity but not always. Probably something I am doing wrong but we'll see.

    The 70 and 180 seem to AF very good.

  • #390
    David K

    Hey Woody,

    Good to see you over here and can't wait for a bunch more guys to join us. Regarding the AF, I need to do some more testing too. Roger says he's got the way the AF works figured out and knows how to “trick” it when need be… and he's pretty smart about this stuff. Got a friend request from you and am more than happy to accept once I figure out how 😮

  • #391
    David Farkas

    Hi Guys,

    I find the AF on the S2 to be very accurate and repeatable, much more so than a Nikon or Canon pro body. I think the biggest stumbling block is understanding how the AF system on the S2 works. Once that is understood, life becomes much easier. For instance, the AF isn't a single point in the crosshairs, it is more an average of what is in the central circle. So, if a high-contrast object is in the circle, but outside of where you want focus to fall, you will be disappointed. Also, because the DOF is so narrow on the larger sensor, you will find that it is better to err on the side of focusing to the front of an object/subject rather than just behind it. DOF will fall behind, but will be non-existent going forward.

    Once you figure out how the system works, it is very easy to work with it. At first, it required conscious thought, but now I just use the system without thinking about it. And almost 100% of my shots are properly focused. This rate was admittedly much lower when I first started using the S2. The camera hasn't changed much (apart from firmware tweaks to the AF system), just my use of it. I hope this makes sense.

    Incidentally, because the subject is so much larger given the narrower field of view, AF accuracy (or at least ease) on the 180 is actually better than that of the 35. I can't recall ever missing focus on the 180, even in the beginning.

    David

  • #394
    Jack MacDonough

    Good advice David.
    I have had no AF problems other than occasionally with the 35.
    I have noticed a few rare times in post processing a far off scene must not have been focused at infinity, but short of infinity. My new work flow is to visually check the distance setting on the lens at time immediately after exposure, and if not on infinity,then take a backup shot with the distance setting manually reset on infinity.
    Any better procedures?
    Jack

    I would add that this probably was a problem on other pro cameras I have used, but their lenses were not sharp enough to show the issue.

  • #396
    Al Tanabe

    Currently I use mf with activation of the AF through the back button. Focus, compose, then tweak the focus if needed. The AF has worked well on the 70 with no issues.

  • #432
    woodyspedden

    Well, as I said my only problem has been with the 120mm and that happened only twice. I was focusing close to infinity and the S2 just kept hunting.

    I think the best advice is to use Al's method. Using the AF button on the back to get close then tweak seems like a pretty quick and reliable method.

    Anyway I am not knocking the AF of the S2, just sharing my experiences

    Thanks for all the advice

    Woody

  • #440
    Al Tanabe

    woodyspedden;106 wrote: Well, as I said my only problem has been with the 120mm and that happened only twice. I was focusing close to infinity and the S2 just kept hunting.

    I think the best advice is to use Al's method. Using the AF button on the back to get close then tweak seems like a pretty quick and reliable method.

    Anyway I am not knocking the AF of the S2, just sharing my experiences

    Thanks for all the advice

    Woody

    I have found that AF, any brand, does not always agree with my framing and point of focus. With Nikon, I got 51 opinions on what I should be focusing on, all within the center of the frame of course. So even with the superb AF from Nikon, I ended up doing the same with that system, rear button focus compose, adjust, shoot.

  • #493
    Mark Gowin

    David Farkas;52 wrote: Hi Guys,

    I find the AF on the S2 to be very accurate and repeatable, much more so than a Nikon or Canon pro body. I think the biggest stumbling block is understanding how the AF system on the S2 works. Once that is understood, life becomes much easier. For instance, the AF isn't a single point in the crosshairs, it is more an average of what is in the central circle. So, if a high-contrast object is in the circle, but outside of where you want focus to fall, you will be disappointed. Also, because the DOF is so narrow on the larger sensor, you will find that it is better to err on the side of focusing to the front of an object/subject rather than just behind it. DOF will fall behind, but will be non-existent going forward…

    David, An explanation of how the S2 autofocus works would make a great addition to your S2 “how to” video series.

  • #576
    Doug

    My experience coincides with Atanabe's… I have the rear button set up to AF while pressed. I have only the one S lens, the 70mm. Sometimes I'm not sure if the AF has adjusted focus or not when shooting a new subject at a somewhat different distance… it's so fast and quiet (but then my hearing is bad anyway). So I'll focus on something quite close, and then on the desired subject to be sure. I am impressed…

  • #578
    David Farkas

    Doug;275 wrote: My experience coincides with Atanabe's… I have the rear button set up to AF while pressed. I have only the one S lens, the 70mm. Sometimes I'm not sure if the AF has adjusted focus or not when shooting a new subject at a somewhat different distance… it's so fast and quiet (but then my hearing is bad anyway). So I'll focus on something quite close, and then on the desired subject to be sure. I am impressed…

    Doug,

    Instead of moving the camera, focusing on something closer, then moving back to your original subject and refocusing, try just racking the lens. Because the lenses are always ready for manual focus, just turn the focus ring all the way to one side and then tap the rear thumb AF button again. Very quick and easy way to make sure the camera has indeed locked focus where you want it.

    David

  • #592
    Doug

    The best ideas seem obvious in retrospect. I'll try that! 🙂

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