The reason the (slight) miss sync is obvious on the lead figure, and not so much on the others is because he is at the border of the light and shadows. The difference is not caused so much by his movement, but by the movement of the tree leaves that give a different shadow pattern between the left and right images. You can observe this same miss sync in the left foot of the middle figure in blue. It's not so obvious there because the whole figure is in shadow.
You know that perfect synchronization is only possible by following the two known steps:
-First, half pressure, focus.
-Second, full pressure, shoot
In fact there were some failures in attempts to synchronize old equipment, such as Samsung NX1000 despite the fact that the firmware allowed a perfect sync, as was demonstrated 2 years later. Always follow the ritual of those two steps is, then, very important.
But making street photography it is very easy to rush, shoot without sufficient previous focus, due to the haste and that the audition of the synchronization sound is not easy and that we are more aware of the photographied scene than of the green visual image in the screen that confirms that the focus is O.K.
But if that had happened in the photo that you comment then the differences would have been greater and also affected the rest of the scene.
Perhaps the small difference that you point out is due to the different luminous incidence in both lenses because in fact the rest of the people in the background have a faster movement: they walk and they have not stopped to observe.
Thank you very much for your comments! :-) :-)
On the other hand:
I have proposed in the group 3D photo of Yahoo to do several test to assess if in the current Sony equipment, mounted side-by-side, it is possible to compensate the excess of stereobase for made normo stereo, modifying the focal distance, according to the Gerhard Herbigg golden rule:
There is a guest post about the possibilities of the cable manufactured by Sony (VMC-MM2) for the synchronization of its current Sony Alpha cameras, and its usefulness in stereo photography:
I have been uploading these "street photo" photos this morning trying to show in the Yahoo Group 3-D photo (https://groups.yahoo.com/neo/groups/photo-3d/info) that an excess of stereo base in the Sony Alpha rigs can be compensated by decreasing the focal length of the lens, acording to the first golden rule of Gerhard Herbig (modified):
Focal length * 10 = distance of closest object / stereo base (all parameters in millimeters or any other unit of length)
For that reason in that last dozen of photos uploaded there are photos shot using NEX-5 rig, (as joke named by me w55 cam :- ), as homage to Fuji W3 but only whit finger sync) mixed with others s3D pics shot with my favorite rig, the twined A6000 cams + Sony VMC-MM2 cable.
I am glad that you are able to distinguish the photos shot with the NEX-5 cams from those shot with the Sony A6000 rig. :-) :-) :-)
Beginners in s3D photograph would not have been able to distinguish that, as you, only visually, and maybe they (of course, not all of us, regular users of Phereo) would have needed a quantifying test with great acuracy, as the smart photo sync test developed by Barry Aldous and described in the latest issue of the journal Stereoscopy edited by the ISU, International Stereoscopic Union.
I have been trying to focus on the stereo base and depth, in both Sony Alpha rigs (NEX-5 and A6000) and only secondarily the good syncronization of the current Sony Alpha rigs, already demonstrated in previous albums:
Tracing of 20mm in length implies that 1 mm corresponds to 1 second.
Coincidence even in half a millimeter implies coincidence in the synchronization in half millisecond or less.
To get more precision we would need a laser with a narrower trace, but it would not be easy to adapt a surgical laser to this test.
I do not think that it is necessary to be more precise in the Barry Aldous test because synchronization of half a millisecond or less, I think it is enough to obtain synchronized 3D photos in our current circumstances.
Timo and Randy, I've never used flash on the A6000 Sony rig with the VMC-MM2 cable. In fact instead, I use 2 pieces (thumb-grips) to increase the ergonomics of the cameras.
Dan, I've observed that operating the shutter on the main camera the sync es perfect but operating the shuter on the sub-camara (the cam conected to the L-shaped plug, right angled) it's not possible shoot the main camera and only one pic (in the sub-cam) is obtained. Also using the DSLRKIT (female + male plugs) you do not need external shutter. The Sony VMC -MM2 cable is available in different countries with differents prices:
https://savemoney.es/asin/Sony%20VMC-MM2
Thank you Georgios. Thanks Path. I'm really enjoying a lot the 3D Sony Alpha rig (A6000 + VMC-MM2 cable+ A6000), almost every weekend. :-)
I tried a flash test with my a5100 pair. Using the built-in pop up flash both cameras flashed when the flash units were up. However the exposure from the two cameras did not match. The right camera (master) had good exposure but the left was over exposed. It appears that the left "saw" both flashes but only metered for one. With one one flash "up" it was even worse. The non-flash camera metered for no flash and then was very washed out as a result of the flash.