Originally Posted by Ken Ross
Shawn, I'm also a bit confused about the A65 & A77. I see lenses advertised for the Alpha cameras that say they have 'autofocus'. Why would you need an autofocus lens if the camera has in-body AF? The same would apply to IS. Some lenses for the Alpha are labeled as image stabilized, but why would you need that if the body has IS built-in? Are these for an older style Alpha camera?
The lens does the autofocus, not the camera. There's a switch on the side to toggle AF/MF. The body just controls the AF through the mount. The camera body has a focus motor though. The LA-EA2 has a focus motor as well. If what you said was true, then ALL Minolta/Sony lenses would be autofocus. There are older Minolta lenses that are MF only and use the (Minolta) Alpha mount. There is an 85mm F/1.4 Rokinson? lens that is new that does not AF.
Now the lens stabilization, that's another can of worms. You're in luck as I've gone down that path already.
For Sony branded Alpha mount lenses, none that I know of have IS built into the lens, as all Alpha mount cameras have it in the body.
Some Sigma branded Alpha mount lenses have IS; others do not.
Here's where it gets fun:
Take the Sigma 17-50 F/2.8. Up until late 2011, the Sigma version had IS built-in on the Sony mount. Now the "new" version of the same lens does not in Sony or Pentax mount, but DOES in Canon/Nikon mount. As Canon / Nikon DSLR's don't have in-body IS, this makes sense.
However, the Sigma 70-200mm F/2.8 (4 versions since inception) has never had IS until the newest version (all in Sony mount). This is a head scratchier as it as adds length and weight to the lens. I have "version 3" of this lens, the HSM II Sigma 70-200, without OS.
Sigma makes a handful of other lenses for Sony DSLR cameras that have IS in body; I think there's a 18-50 F/2.8-F/4 that does, and perhaps others.
Tamron does not AFAIK.
When I still used the Nex5n and Nex-7 with the LA-EA2 adapter I searched all over for lenses that had in-body stabilization as I'm not a very steady photographer. Had the Sigma 17-50 F/2.8 for a while; it was sharp but the zoom ring was stiff.
Only other thing I'd like to add about this:
For autofocus lenses there are two types of af mechanisms - older, noisy "screw drive" type that are loud and terrible for video. I have some myself, like the Sigma 30mm F/1.4, which I use in MF only video mode. Then there's the HSM or hyper sonic motors, or Sony's SSM (Super Silent motor) lenses that are great for video. Examples; 16-50mm F/2.8, 70-200 F/2.8 (SAL70-200G), 70-300 F/4 - F/5.6 (SAL70400G), Some of their cheaper lenses, like the 35mm SAL F/1.8 are not SSM but not too overly loud, and it's $199 and sharp as a tack wide open.
But none of them are as quiet (except for the SSM lenses I listed) as your E-Mount lenses. None of them.
Also Tamron has a nice 70-300mm lens, the USD (Ultra silent drive) that is very quiet as well.
Enough for now. Also, if you're seriously thinking about the A65/A77, get the A77. Same 24mp sensor, but the A77 has AF micro focus adjustment, 2 controls, better articulating screen, weatherproof, top LCD etc.