Cameracraft magazine – Taking your practical photography further

The Alpha 580 – a three-way view

Written by

David Kilpatrick

The list
So, here is how the three types of lens and three types of viewing method interact, to which I have added the NEX/LA-EA1 and the SLT A55/33 behaviours. If you don’t read the rest of this review, please read this. I promise you it took as long to put together as the whole of the rest of the report!
Alpha 560/580 in Optical Viewfinder mode

  • All AF lens types use Phase Detect autofocus, single, auto or continuous including sequence shooting
  • 11 zones of the maximum 15 zones (3 cross sensor) AF are activated
  • Focus modes Spot, Local and Wide Area
  • Exposure metering uses 40 segments, honeycomb pattern. Sensitivity is from EV2 (not very good) in Matrix or Centre Weighted modes, from EV4 in Spot mode (very poor for low light). Can cope with extremely bright conditions up to EV20 (rarely found on Earth)
  • Pressing the Movie button starts filming at the focus distance set; no AF during video. Optical finder blacks out, image is shown on rear screen
  • 95% view of the composition at 0.8X magnification (compared to 0.74X for A3xx series, 0.9X for A700)
  • Optical preview of depth of field using stop-down button, accurate from smaller apertures (f/4 to f/22) but not useful at large apertures (f/1.4 to f/4)
  • Continuous shooting possible at 5fps with AF/AE, 7fps in Speed Priority with locked AF/AE
  • No grid lines or Virtual Horizon display in optical finder

Alpha 560/580 in Quick Live View mode

  • All AF lens types use Phase Detect autofocus, as for optical
  • All 15 zones of the AF sensor are activated (four appear to be ‘assist’ type extensions)
  • Focus modes Spot, Local and Wide area
  • Face Detect and Smile Shutter modes can be used
  • Exposure metering is from the QLV CCD sensor, in 1200 zones. Sensitivity from EV1 to EV17 (a moderate range, slightly better than the optical finder method for low light, OK up to sand or snow in sunshine) in all modes
  • Pressing the movie button has the same focus effect as with optical viewing, with a rapid switch on the rear screen between the QV image and a sensor image
  • 90% view of the final composition
  • No depth of field preview, and no magnified focusing view
  • Continuous shooting limited to 3fps with AF/AE
  • Grid lines and Virtual Horizon display can be enabled


Focus Check LV used for an 8 second tripod exposure at f/9, CZ 16-80mm at 16mm, ISO 100. Horizon level used in camera, verticals corrected in Adobe Camera Raw with lens profile applied and convergence adjusted. This shot is the front cover for a 2011 calendar featuring over 50 images of our home town, Kelso, almost all shot on Alpha, which can be obtained as a printed copy by post from Lulu.
Alpha 580/560 in Focus Check Live View mode

  • Screw-drive lenses focused by the mirror flipping and Phase Detect AF when first pressure is taken on the shutter release, even if CDAF is selected. Continuous AF is not possible either for still or video
  • SSM and SAM lenses focus using Contrast Detection AF from the CMOS sensor if this option is selected. Focusing can be slow and sometimes fails. AF is not possible during video
  • All 15 zones of AF are activated if Phase Detect AF is selected, with Spot, Local and Wide area choices; if Contrast Detect AF is used, centre spot and a Flexible Point (movable on-screen) are the options
  • Face Detect and Smile Shutter can be used
  • Exposure metering is from the main CMOS sensor, in 1200 zones, with Matrix/Centre Weighted and Spot options. The sensitivity is far superior to the other modes, going down to EV minus 2 in all modes, and up to EV17 in the A580. Note that the A560 is limited to EV16, which implies the sensor is saturated. This means its true ISO range has been curtailed by 1EV, by overexposing (and should really be ISO 200-12,800 with a 25,600 extension). The 580’s true range is assumed to be a genuine 100 to 6400 with extension to 12,800
  • Pressing the Movie button smoothly transitions from Live View to the movie 16:9 crop, but you must focus first as it does not initiate refocusing in any mode with any lens. AF during video is not possible
  • 100% of the final composition is visible, with 7.5X or 15X critical magnification to check focus, and very accurate previewing of colour, white balance, contrast, sharpness and exposure
  • Very accurate depth of field preview shows precisely on screen what you will get, because the magnifier works during stop-down – you can even press the stop-down button while viewing the magnified image, and see the sharpness change without losing your selected magnification
  • Continuous shooting at 5fps or Speed Priority 7fps possible, but no C-AF, and AE only at 5fps
  • Grid lines and Virtual Horizon display can be enabled

Alpha NEX-5/NEX-3 with LA-EA1 adaptor

  • The NEX should in theory function exactly like the Alpha 580, but without the provision to do a Phase Detect autofocus action in Live View prior to shooting video, or with each still shot. The normal LV of the NEX is equivalent to the Focus Check LV of the 580/560 but with Contrast Detect AF enabled permanently in-camera
  • E-mount NEX lenses (no adaptor needed!) can focus continuously without problems – they are designed to do so, and have a motor like SSM but even quieter and smoother
  • Screw drive lenses fitted using the LA-EA1 adaptor can not autofocus at all, manual focus with 7X/14X magnified check must be used
  • SAM and SSM lenses via the adaptor can autofocus on shutter pressure only, AF-S mode and can not continuously autofocus, including during video. It is possible to refocus during video with first pressure on the shutter
  • Spot, Wide Area, Flexible and 25 Local focus points can be selected (wide area also uses the 25 points)
  • Exposure is from the main sensor using 49 segments unlike the 1200 zones of the 580/560, and the sensitivity is extended – from EV0 at ISO 100 (not present on the camera!) at f/2.8, which matches the EV minus 2 at f/1.4 of the A580/560, right up to EV20 which is one stop brighter than these can meter off-sensor in relative terms
  • Depth-of-field preview is not available, and the NEX always shows the live image at the full aperture of Alpha lenses

The Alpha 55/33

  • The A55/33 use a Phase Detect system which is always in-line and active, to feed both the EVF and rear screen – all its viewing options are electronic, all are supplied from the main CMOS sensor
  • Contrast Detect AF is not provided, but Manual Focus with the usual 7/7.5/14/15X magnification options can be used
  • AF uses a 15-point module with 3 cross sensors
  • All types of lens including screw drive can autofocus during 7fps or 10fps sequences and video filming. The only difference between lens types is the smoothness of AF, and the noise recorded during video – some screw drive lenses, such as the CZ 16-80mm, are actually quieter than SAM lenses like the 18-55mm and appear to follow focus just as well
  • Metering is from the main CMOS sensor (ISO 100-12,800) and ranges from EV minus 2 to EV17 whether using the 14 or 16 megapixel sensor. This is quite revealing when the A560’s 14 is limited to EV16; the Translucent mirror is clearly removing enough light to remove the ‘need’ to oversaturate this sensor
  • Depth of field preview, along with exposure/WB/contrast/sharpness preview, is fully implemented but the eye level EVF is not sufficiently accurate, the rear screen is often better for previsualing images
  • Grid lines and Virtual Horizon visible at eye level as well as on rear screen

This round-up of the three modes of the A580/560, compared to the other video-capable Sony models, may show you just how complex the operation and compatibilities of the Alpha have become in the last year. I would argue that this is an unsustainable situation; to many combinations either work differently, don’t work, or require detailed knowledge of how to set up the camera. This is contrary to Sony’s philosophy of making photography simpler and replacing mechanical complexity with clever electronics. My feeling is the the A580/560 design is complex without providing the solutions offered by either the NEX or the SLT A55/33 design, and will be the last generation of this type.
If Sony can not improve the Contrast Detect AF function of this camera type sufficiently to remove the need for Quick Live View entirely, they will not be able to bring video to full frame or to higher end APS-C without adopting the SLT design across the board. This may be unacceptable to the marketplace if the Translucent mirror can not be lifted for ‘pure’ shooting. I’m fairly sure the next step is an instant-return, or lock-up, SLT design – that, or the CDAF continuous focus algorithm for SAM and SSM lenses will finally have been cracked.

Comments

19 responses to “The Alpha 580 – a three-way view”

  1. OldNoob avatar
    OldNoob

    David,
    Thank you for the review and helping me understand my camera better.
    I do have many questions,, but i will only ask one.
    Which Auto-focus mode do you feel is most accurate when using Minolta Primes such as the 50mm f/1.7?
    The reason i ask is from experience with terrible back-focusing when using a a560 with my Minolta lenses ,, which are tack sharp on my a100.
    After reading your review i see it may have just been a matter of me not understanding the camera and the different focus modes.
    To be honest ,, i dont really care about the Live view, i use the optical viewfinder for everything. Yeah, im that old.
    Anyway, thanks again.

    1. admin avatar
      admin

      I always use single shot, centre AF point. The A580 has not proved immune to FF/BF issues though and I am afraid it tends to go with that type of AF sensor despite continued improvements. I have only recently started using the 50mm f/1.4 lens after getting the A77, it’s the only camera I have owned so far which focuses it accurately.
      David

  2. admin avatar
    admin

    The Sigma is a much better lens. Since you have a choice between OS and SSS there really isn’t an issue. The Sigma is so much better at the long end of the range, optically.
    David

  3. william9 avatar
    william9

    Thanks David. Now that I’ve gotten an a55, I’ve been thinking of selling my Tamron 18-250 and getting the Sigma 18-250, for the potential of better IQ and less distortion, as well as the OS for video. Your review comments stopped me for the moment. From your reviews, it sounds like you’d recommend this kind of switch (it’s affordable), so long as the video would be in the 18-100 range or so. Am I correct in that?
    BTW – do you still find that you get better IQ at 200-250mm from the Sigma compared to the Tamron? Are they pretty much equal from 18-150? Thanks again for your advice.
    William

  4. admin avatar
    admin

    I did not use a tripod; at times, I used a binocular support (a monopod with a sort of Y-shape at the top) because I was so cold I could not hold the camera still at all. The stabilisation on the Sigma 18-250mm seems fine for movies up to a middle setting, maybe 100-150mm. At a certain point (always at 250mm) it becomes impossible to pan or move the camera without the distorted effect. I think this is due to the type of stabilisation used in that lens, and some other Sigma lenses might behave differently. What I do know for sure is that the in-body SSS does not produce the same effect.

  5. william9 avatar
    william9

    David,
    I was struck by your comment about video and the Sigma OS system: “Don’t think that in-lens OS will be your solution to longer clip lengths before overheating shuts the system down. It doesn’t agree with the movie mode, in contrast to SS which works well.”
    Q: Did you use a tripod when making the video on YouTube? If so, could the “ripple” effect due to the OS stabilizer being on and the lens trying to stabilize something that is already still — the same kind of difficulty as leaving the SSS on when using a tripod?
    Is there any reason to get a Sigma OS lens for a55 or a580 video — or is it always best just to go with SSS and a steady hand?
    Thanks, William

  6. LEdgars avatar
    LEdgars

    In terms of camera handling I would rate Minolta 7D as best camera made by Minolta/Sony. Suppose A700 and A900 also were designed by Minolta, but ‘improved’ by Sony and both are already one step down.

  7. gwbuffalo avatar
    gwbuffalo

    The D-lens distance encoder is great for ADI calculations, and in that case focus produces a distance measurement rather than the other way around. But the D encoders are mechanical, and are too coarse to allow the camera to finely control focus motor speed for silky smooth contrast AF.
    I feel sure the encoder in the E-mount lenses is a high resolution encoder (probably optical) for that reason. Since contrast AF doesn’t really care about distance, I’m pretty sure the LA-EA1 and Alpha cams don’t even use the D encoders.
    With much less mechanical backlash (gear slop) than body-driven lenses, the SAM and SSM lenses contrast focus smoother and quieter (and the LA-EA1 with not drive motor can only focus with them anyway). But E-mount lenses will always contrast focus much better than any of them because there is precise feedback of focus group position and speed to the camera.

  8. gwbuffalo avatar
    gwbuffalo

    Excellent article! The best ever explanation of the three viewing systems in use on these newest Alphas.
    One thing regarding the suitability of SSM and SAM lenses for contrast detection AF is the lack of a focus group position encoder in the 8-pin A-mount lens system.
    The E-mount lens system is most suitable for contrast detect AF not just because the focus motor is smooth, but because the control system has knowledge of the exact position of the focus group.
    I believe that is the purpose of the extra 2 pins on the E-mount lenses. It is the A and B phase of an electronic position encoder on the focus group.
    Such an encoder allows the control system to move the focus group very precisely in executing the contrast AF scheme. All A-mount lenses lack this encoder (not needed for phase detect AF). A side benefit of the encoder is the camera body can enter manual focus check magnification automatically whenever the focus ring moves the group.

    1. admin avatar
      admin

      The D-lens specification is supposed to report a fairly accurate focused distance and the initialisation of the A-mount lens, on startup, has always included a ‘focus range check and park’ process. We need to wait and see how things develop. Pentax devised a very good way to get single shot CDAF with any lens, including screw drive – a simple process by which the camera does a ‘big’ focus range check, maps the result; homes in on the approximate position for sharpness, and does a second smaller sweep around around this; then it moves to the detected peak contrast position and if necessary does a tiny final shuffle; and locks. I don’t think the story is over yet.
      There are two obvious options open to camera designers. One is very simple – detect focus from the focusing screen in an SLR design. Optical devices like the split image RF or microprism create phase contrast in a form the eye can see, and what the eye can see can also be detected by a sensor. The second option is go down the Contax N body route, and build a fine focus mechanism into the sensor carriage – have a sensor which can move forward of backward over a small but functional range such as 3mm. Used with a manually focused lens this could allow enough video focus adjustment with shorter focal length (below 100mm) lenses to enable video CDAF.

  9. George avatar
    George

    Now that you have reviewed extensively both the Alpha 55 and the Alpha 580 which would you choose if you needed only one camera for family and vacation shots, no studio?

    1. admin avatar
      admin

      Alpha 55. GPS, eye level video shooting, autofocus during video, quiet operation, smaller, lighter, EVF is great in low light.

  10. DavieR avatar
    DavieR

    The 2s timer for MLU would not work for me. So often, I raise the mirror and wait for the right moment, perhaps waiting for the wind to drop or for someone to move into/out of frame.
    Thanks for a couple of really interesting reviews – this one and the A55.

  11. admin avatar
    admin

    With all the latest Sony models – NEX, SLT, 560, 580 – you do not see image noise in typical shooting conditions until ISO 3200, provided you process the raw file sensibly. That does not mean cranking up to maximum NR either. I am just going to add a link to a full size version of the antiquey furniture shop interior which is at 1600. I’m sorry these large file download links are restricted to subscribers, but I need to limit bandwidth and obtain subscriptions alike. Anyone with an existing YUDU or Payloadz subscription, or a magazine subscription paid up, can email me [email protected] and I will manually upgrade their Free registration on the site to Normal or Premium status as appropriate.

  12. jfirneno avatar
    jfirneno

    David:
    That report was extremely interesting (and for me timely). Especially enlightening was your discussion of High ISO low light handling by Sony vis-a-vis Nikon’s strategy. This would explain some of the results I’ve seen on various sites and from photos I’ve received from people working with the A580. The statement you made about ISO 1600 being virtually noise-free caught my attention. My A850 has fairly strong noise from ISO 800 and above (raw, right out of the camera). So I was wondering can you quantify the raw file low light ISO advantage of the A580 over the A850 (or A900) in terms of stops? I promise this will be my last low light question.
    Regards
    John

  13. Dan Vincent avatar
    Dan Vincent

    I would figure that the 2s timer would be enough to tame most vibrations, even with FCLV’s double-dip of the mirror. Of course, once you nail the focus, you could leave FCLV, wait a few extra seconds, then trip the shutter. Yes, it’s not as good as having the a900’s multi-fire MLU mode, but I’d say it’d get the job done for 99.9% of the people who relied on 2s timer before.

  14. admin avatar
    admin

    Bingo! It’s only a 2 second respite, but in FCLV mode combined with the 2 second selftimer, the mirror lifts for the 2 seconds and the shutter closes – both optical and screen finders are black. Then the shutter fires and the mirror briefly flips to return to FCLV mode.
    This doesn’t work with the wireless remote release, if set to remote and the 2 sec button used, you just get a rapid-bleep 2 sec delay and normal firing. It does work with the wired cable release.

  15. admin avatar
    admin

    My error – I was thinking about the lack of it in Focus Check LV mode when testing this. I’ve altered the paragraph involved to state this. For me, not having the mirror drop and rise in FCLV mode would be the most important (probably impossible) change. That’s because FCLV is the focus and viewing mode I would use on telescopes, microscopes, macro bellows and similar setups needing zero vibration. Of course I have also been working with the Alpha 900 for two years, and that has a true mirror lockup mode not just a pre-lift.
    But you have given me an idea. I have not tried combining the FCLV mode with 2 second mirror prelift or 10s self timer. I’ll check this out right away and add something to the review.

  16. Dan Vincent avatar
    Dan Vincent

    David,
    The a580/560 does have Mirror Lockup in the 2s self timer. It’s right on the Sony specs pages for the cameras.

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