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  • #46
    Re: C-AF disappointing

    Originally posted by TonyR View Post
    No, I don't think so. If Rls Priority-C was set to the default On, then the camera starts shooting before focus is achieved. So, if you were using Sequnetial-H mode, your results are as I would expect. You must use Sequential-L to get C-AF with burst shooting.

    It can do this:

    I had shutter release prio set to Off from the beginning.

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    • #47
      Re: C-AF disappointing

      I'm almost certain CAF is actually related to the actual frame rate you choose, not whether it is set to L or H.

      So, if you limit H to, say, 15fps you'll get CAF between each frame. That's certainly how mine behaves, anyway.
      Regards,
      Mark

      ------------------------------
      http://www.microcontrast.com
      Too much Oly gear.
      Panasonic GM5, 12-32, 12-35, 15, 35-100, Laowa 7.5.
      Assorted legacy lenses, plus a Fuji X70 & a Sony A7S.

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      • #48
        Re: C-AF disappointing

        Originally posted by drmarkf View Post
        I'm almost certain CAF is actually related to the actual frame rate you choose, not whether it is set to L or H.

        So, if you limit H to, say, 15fps you'll get CAF between each frame. That's certainly how mine behaves, anyway.
        Look at Page 46 of the manual.

        Sequential High -

        "Pictures are taken at up to about 15 frames per second (fps)
        while the shutter button is pressed all the way down. Focus,
        exposure, and white balance are fi xed at the values for the
        fi rst shot in each series."

        We are talking about the E-M1 MkII right?

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        • #49
          Re: C-AF disappointing

          I agree with TonyR I always use Low for CAF .
          Rob.

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          • #50
            Re: C-AF disappointing

            Then H FPS and CAF would be meaningless when used together. And the statement regarding CAF on page 43 is contradictory with page 123. I use mode 2 most of the time, sometimes mode 1 depending on light angle and background.

            And still does not explain why I get zero frames in focus.
            Last edited by Tordan58; 29th May 2017, 01:54 PM. Reason: Spelling

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            • #51
              Re: C-AF disappointing

              Originally posted by TonyR View Post
              Look at Page 46 of the manual.

              Sequential High -

              "Pictures are taken at up to about 15 frames per second (fps)
              while the shutter button is pressed all the way down. Focus,
              exposure, and white balance are fi xed at the values for the
              fi rst shot in each series."

              We are talking about the E-M1 MkII right?
              With mechanical shutter, yes.

              Where does the manual talk about these issues with the electronic shutter?

              I have been using L for ages (too many images with H to deal with!) so I'm relying on memory, but I still believe it will CAF at 18fps with the electronic shutter and I thought you could only reach that on H?
              Regards,
              Mark

              ------------------------------
              http://www.microcontrast.com
              Too much Oly gear.
              Panasonic GM5, 12-32, 12-35, 15, 35-100, Laowa 7.5.
              Assorted legacy lenses, plus a Fuji X70 & a Sony A7S.

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              • #52
                Re: C-AF disappointing

                Originally posted by drmarkf View Post
                With mechanical shutter, yes.

                Where does the manual talk about these issues with the electronic shutter?

                I have been using L for ages (too many images with H to deal with!) so I'm relying on memory, but I still believe it will CAF at 18fps with the electronic shutter and I thought you could only reach that on H?
                No, 18 fps is the highest burst rate in Sequnetial-L with silent shutter. The manual omits to specifically talk about how AF works with Sequential-H and silent shutter but both H with mechanical and Pro Capture-H say the AF reverts to S-AF if C-AF is set.

                Also, I just tested Sequential-H, silent shutter at 15 fps and it only focuses once at the beginning.

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                • #53
                  Re: C-AF disappointing

                  Originally posted by drmarkf View Post
                  With mechanical shutter, yes.

                  Where does the manual talk about these issues with the electronic shutter?

                  I have been using L for ages (too many images with H to deal with!) so I'm relying on memory, but I still believe it will CAF at 18fps with the electronic shutter and I thought you could only reach that on H?
                  I used Seq low at 18fps on all the shots on Bempton and for sure CAF was active all the time.
                  Paul
                  E-M1ii, Pen-F and too many lenses
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                  Portfolio Site
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                  • #54
                    Re: C-AF disappointing

                    Hi Tord I would not have thought that your experience with CAF would have been a setting issue given the images that you post. You are a season Olympus pro. I am happy with my copy of the MKII and 300 F4 but I only use drive modes with antishock (diamond) and LF with CAF. At first I thought this may have been the issue but your static CAF tests shows a front focusing issue.
                    Do you think the image you show is an oof issue or a shutter shock issue?
                    Which drive modes were you using? Will be interested what comes back from Olympus support.
                    John

                    OM-D E-M1, 12-40 f2.8 Pro, Tamron 14-150mm f5.8, E5, E3, Zuiko 50-200mm SWD, Zuiko 12-60mm SWD, Zuiko ED 70-300mm f5.6, 50mmf2, Zuiko ED 9-18mm f5.6, Sigma 50-500mm f6.3, EC14, EC20, RM-1, VA-1

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                    • #55
                      Re: C-AF disappointing

                      Originally posted by TonyR View Post
                      No, 18 fps is the highest burst rate in Sequnetial-L with silent shutter. The manual omits to specifically talk about how AF works with Sequential-H and silent shutter but both H with mechanical and Pro Capture-H say the AF reverts to S-AF if C-AF is set.

                      Also, I just tested Sequential-H, silent shutter at 15 fps and it only focuses once at the beginning.
                      Thanks - I'll correct my brain should I ever need to use those speeds!
                      Regards,
                      Mark

                      ------------------------------
                      http://www.microcontrast.com
                      Too much Oly gear.
                      Panasonic GM5, 12-32, 12-35, 15, 35-100, Laowa 7.5.
                      Assorted legacy lenses, plus a Fuji X70 & a Sony A7S.

                      Comment


                      • #56
                        Re: C-AF disappointing

                        Originally posted by Tordan58 View Post
                        Then H FPS and CAF would be meaningless when used together. And the statement regarding CAF on page 43 is contradictory with page 123. I use mode 2 most of the time, sometimes mode 1 depending on light angle and background.

                        And still does not explain why I get zero frames in focus.
                        Yes, Sequential-H and C-AF is meaningless when used together. But that is why the manual says the camera reverts to S-AF when you set both of these. The question is, were you set to any (silent, normal or Pro capture) of the Sequential-H settings? If you were you would probably not get any sharp shots of a moving subject like a bird.

                        The manual is [email protected] ! We have to deduce what it means and what the camera really does. The stuff on page 43 assumes you have used the default settings. C-AF starts when you half-press the shutter. The table on page 123 is very confusing but sort of works if you assume that the photographer is using single shot and not sequnetial. So, the AF starts continuously focusing when you half-press the shutter and stops (or locks) when you fully press it, in mode 1 or 2. In sequential shooting it only "locks" momentarily to take the shot before continuing to C-AF between shots (and then only if you are in an L mode).

                        Anyway, as a long-time E-M1 MkI and MkII user, I can assure you that the MkII must be in sequential-L to use C-AF (unlike the MkI after firmware update 3.0!). The results are not perfect but you can get a number of well-focused shots from a burst. On static subjects, you will see a variety of sharpness as the AF hunts around. I don't use C-AF for static subjects, ever.

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                        • #57
                          Re: C-AF disappointing

                          Originally posted by birdboy View Post
                          Hi Tord I would not have thought that your experience with CAF would have been a setting issue given the images that you post. You are a season Olympus pro. I am happy with my copy of the MKII and 300 F4 but I only use drive modes with antishock (diamond) and LF with CAF. At first I thought this may have been the issue but your static CAF tests shows a front focusing issue.
                          Do you think the image you show is an oof issue or a shutter shock issue?
                          Which drive modes were you using? Will be interested what comes back from Olympus support.
                          I suspect that the front-focusing issue with C-AF comes from the way that S-AF and C-AF differ in operation. The following is mostly a guess based on a few snippets from Olympus slides and web sites.

                          S-AF uses hybrid PDAF and CDAF so it probably uses CDAF to fine-tune the focus. CDAF favours the highest contrast part of the subject under the focus point rather than the closest part.

                          C-AF is looking for movement and is much more dependent on PDAF (see https://www.olympus.com.au/Products/...ed-Performance - High-speed AF system) so it may be less accurate and it may have an algorithm that hunts back and forth a little (I think it does this more with AF Lock set to higher values). The PDAF system is designed to favour the nearest subject which is something that CDAF cannot do. So, when you use C-AF on the focus target used above it may pick out the part of the subject that is nearer than S-AF would. So, on average, with this target, you may get front-focus.

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                          • #58
                            Re: C-AF disappointing

                            Originally posted by Ross the fiddler View Post
                            When you review the images in camera, thumbnail size, it will show where the AF point is located. Are those AF points showing where you intended?
                            I wish I could check this however don't have the camera any longer. I still have the files (RAW). Is there a way to find out using Olympus Viewer?

                            My Gallery on 500px

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                            • #59
                              Re: C-AF disappointing

                              Originally posted by Tordan58 View Post
                              I have a hard time believing it's a setting issue, as all shots are OOF. I get the feeling there is a consisent failure in acquiring focus in C-AF.

                              I used mechanical shutter, H fps (from 8 to max) and IS Auto, except the end of the session when I disabled IS to see if that was the culprit - no improvement seen, though.
                              I just noticed that you said this in an earlier post. Mystery solved. It will not be doing C-AF.

                              It is pretty stupid of Olympus to have these arcane, complex rules. Perhaps if the AF displayed in the viewfinder was actually S-AF when you use Sequential-H it would be better. Or some message gets displayed when you choose C-AF and Sequential-H. Anyway, it is poor user interface design. It would be easy to miss in the manual and lots of people expect to be able to use a camera without reading it.

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                              • #60
                                Re: C-AF disappointing

                                OK so reviewed the pictures once more and focused on the first frame in sequence. There are something like 1000 of pictures, time and patience are limited so cannot inspect every single one. Most are crap anyway.

                                I found one exception. It's not perfect but pretty accurate from focus point of view. I also know for sure that the E-M1 would have nailed it, so it's not a tremendous achievement considering the Mark2 performance on paper.


                                Then more samples showing the mediocre results that the C-AF (non TR) produces. The Tern is progressing slowly against a steady head wind, I fired a burst hoping to capture a nice dive.


                                And one showing how bad it gets with C-AF + TR. I tracked the duck and fired a burst as it had slowed down almost to a halt, expecting to freeze some nice splashes.


                                Both have clean background, good contrast, subject occupies a large enough part of the frame, all conditions met for the AF to acquire focus instantly. Which it did, and still not capable of focusing correctly.

                                Can anyone explain what is going on?

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