JJack: Sigma mount is supposed to be more-or-less compatible with Pentax K-mount, right?
So will this lens work with K-5 and K30?
The same question about 120-300mm F2.8 as well.
I had a SD14 with the 18-50mm f2.8 and I found that K mount lenses could be fitted to the Sigma body, but they are slightly loose (I secured my modified 50mm with bluetack!), and Sigma mount lenses will not mount on K mount bodies as the tabs on the Sigma Bayonet are slightly thicker that the K mount tabs.
Anyway's if you're gonna buy SA mount glass you might as well put it on an SD1 ;)
km25: If these new Sony cameras are using beam spilters in place of a moving mirror. Are they: 1. Show light loss. Say a lens that is a f2.0, do to spilter becomes say f2.8. A loss of light. 2. The beam spilter is in the opical path, does that degraded the image from the lens. 3. Most of the light would be sent to the sensor. Would this not degrade viewing.Just asking. This is not a new idea. Movie cameras, like Bolex and Canon still 35mm high speed cameras used the same. But there was a price to pay.
I've owned an Nex 5n and I now own an a37... I think that the mirror definately reduces detail (marginally) and also increases noise by a 3rd of a stop as you need more exposure to get the same shot, which can be a big deal depending on the light you have to work with and on your taste.
It is possible to remove the mirror from SLT cameras if you're careful, as they are held in place by a hinged bracket.
I only use old lenses and manual focus so for me the a37 with the mirror out and nice old M42 glass it's the best camera I've used for manual focus. And as you can get M42 adapters with focal lengths programmed into them it means the in body stabilization works too.
I doubt I'd have the nuts to take the mirror out of the a99 though! :P
Roger: How about a digital back for all the old film cameras. So you don't have to buy, buy, buy, a new camera every year or two? You know where you buy a digital back for your film camera, maybe even two, three, or four with different sensors. No new cameras just a back Leica did it they just charged to much. Your good old film camera and lenses with a new back. All of my old film were able to change screens, prisms, and backs.
Something to think about.