Sony 28-75mm f2.8 SAM

[bakubo]

About 30 minutes ago I was at a big Bic Camera in Tokyo. They had the new Sony 28-75mm f2.8 SAM lens on an A900. I was amazed at how leisurely it focused. Slow. Just going from 3 feet to 12 feet was slow. There was also a Canon 5DII with 24-105mm f4L nearby so I tried it. Fast. Also, a Nikon D90 with a Sigma 18-250mm f3.5-6.3 OS HSM. Fast. Also, a Canon 50D with a Tamron 18-270mm f3.5-6.3. Fast. I have the Tamron 28-75mm f2.8 in Canon mount so it has an in-lens motor, but not USM. I don't recall it being so slow on my Canon 30D. Actually, the Sony lens on the A900 seemed quite a bit slower than most screw-drive lenses on my A700. Anyone know what the deal is?

[KevinBarrett]

Slow and steady nails the focus?

[bakubo]

Slow and steady nails the focus?

Well, it sure was slower than most of my screw-drive lenses and was also slower than I recall the Tamron 28-75mm f2.8 on the 30D and it does not have USM for Canon either. It sure didn't seem any more accurate than the other lenses and bodies I checked today.

[bossel]

I have the KM 28-75/2.8 screw drive on the A700 and I'd say it's rather quick focussing. No need for me to 'upgrade' to the new lens.

[bakubo]

I have the KM 28-75/2.8 screw drive on the A700 and I'd say it's rather quick focussing. No need for me to 'upgrade' to the new lens.

Yeah, that doesn't surprise me at all. Based on what I saw today I wouldn't trade the screw drive KM for the SAM drive Sony either. Maybe there is some explanation for it. I don't mean it creeped, just that it was noticeably slower than all the other lenses I am used to. My Sony 18-250mm can be slower in some situations, but most of the time is a lot quicker than what I saw today.

[KevinBarrett]

It is certainly a disappointment. I prefer f/2.8 or greater aperture lenses mainly for their ability to grab focus faster, rather than their light-gathering capacity. To slow it down with an inferior in-lens motor is a shame.

[Greg Beetham]

What's going to happen when the start removing body focus motors? And in what model are they going to start doing it? The next one?
Greg

ps. Otoh they might have a plan, they might be intending to introduce a seperate line of DSLV type cameras with interchangable A-mount SAM lenses...then they can revert the DSLR camera line back to normal....Very clever Sony, you had me there for a moment...

[bfitzgerald]

I dunno, cannot say SAM has impressed me on the lenses I tried, the 50mm f1.8 is no match for the 1.7 for AF speed, notable difference.

I knew it was a bad idea, el cheapo in lens motors. Now to be honest I think SSM might make sense for a few lenses (16-80mm), this lens is well, erm evidently a much more expensive Tamron, so why bother anyway?

I'm just waiting for the inevitable in body AF motor removal shortly

[KevinBarrett]

Hopefully, with those screw-driven primes out there, including AF Zeiss designs with Sony branding, they'll leave the AF motors in the metal-bodied cameras, at least.

[stevecim]

since the SAM lenses I've tried aren't quite or fast focusing, makes me think Sony added the motors because Nik/Can kits lenses have motors.(me too sort of thing) Surely Sony would not drop the body motor this early in the game. You would want to have your whole lens line up with SAM/SSM for at least 3-5 years before dropping the body motor. the moment they drop body motor, you would lose AF on around 90% of Sony/Minolta/third party lens. But I guess you can never tell what Sony will do

[bfitzgerald]

Sony seem to be watching Nikon a lot, and I am convinced that they will take the AF motor out of entry models (just a case of when), I doubt they would be as brave as to have a go at A5xx range models, not yet anyway. Sony don't want people going on ebay buying up all sorts of nice cheap lenses, that's why the 50mm f1.8 is SAM, and the new kit lenses etc. They will say most entry buyers won't buy lenses anyway, and if they do they can pick up the cheap nasty plastic SAM Sony ones

There is no real advantage to SAM, check out this 28-75mm, it's larger than the screw drive one, slower to AF. Sure make a real SSM version, but what Sony have missed is that SAM is noisy, Canon and Nikon make quiet kit lenses, or pretty quiet. Also look at the problems Pentax have been having with motor failures. I'd be pretty shocked if these lenses last decades like the screw drive ones do.

Problem for Sony is you cannot force people to buy their own lenses, but you can punish them with MF for doing so. Next up for removal is the mechanical aperture control...

[Greg Beetham]

We'd better not start rejoicing in the streets just yet, that Sony might introduce a seperate camera line for the SAM lenses and still support conventional full featured DSLR's with in body focus motors.
It doesn't seem likely (too me) that the SAM lenses would be a good choice for a still camera with video capability if they are slow to focus and noisy to boot, not that I could care less if that is actually what does transpire....All I care about is that Sony fixes the Macro flash system back the way it was before they meddled with it....and continue to do R&D on building a better DSLR (ie. quality, functionallity...features), with the features that should be there without compromising the cameras STILL taking functionallity in order to incorporate some almost useless gimmicks.
Greg

ps. They did a good job on the A550 in some respects though, especially with the auto HDR function, and the high frame rate, even the face detect might proove useful, but it's probably more of a high lattitude camera with it's good high ISO ability, here where I live at about Lat 20deg South of the Equator we need a camera that starts out at ISO50 not ISO200..unless you like shooting at night/dusk/twilight a lot that is.

[Greg Beetham]

I was doing a little snooping on some lens details, just for the heck of it...
Sony 28-75 f2.8 SAM 565g (L94 X W77.5mm) $800 US B&H
Tamron 28-75 f2.8 510g (L92 X W73mm) $459 US B&H
Sigma 24-70 f2.8 EX DG Macro 715g (L115 X W89mm) $569 US B&H
[new] Sigma 24-70 f2.8 EX DG HSM 790g (L94.7 X W88.6mm) no price at B&H yet.

On the face of it it's hard to see any advantage in the Sony SAM lens if it's slow to focus, and taking the price into account, also didn't someone (David maybe) say the optics were very similar to the Tamron's.
The Sigma's are physically larger than both the Sony and Tamron lenses (82mm filter vs 67mm) because of the starting wider angle, it's interesting that the new Sigma HSM is physically smaller (although heavier) than it's companion non HSM version.

Not all the SAM lenses are expensive though..
Sony 55-200 f4-5.6 DT SAM 305g (L85 X W72mm) $230 US B&H
Sigma 50-200 f4-5.6 DC OS HSM 420g (L101.9 X W74mm) $199 US B&H (both have 55mm filter size)
Tamron 55-200 f4-5.6 Di-II LD 300g (L83 X W72mm) $164.95 US B&H (52mm filter) Assume it's a motorized lens neither B&H or Tamron's own site-specifications list whether it is or isn't. (This lens gets very good owner reviews).
....an amazing price for Sony....

Sony 18-55 f3.5-5.6 DT SAM 210g (L70 X W70mm) $200 US B&H
Sigma 18-50 f2.8-4.5 DC OS HSM 395g (L74 X W88.6mm) $199 US B&H (The Sigma is physically larger because of the large starting aperture, has 67mm filter vs 55mm for the Sony lens).
....although a slower lens it's another amazing price from Sony....

I compared a couple more but this message is starting to get quirky to try and type...must be reaching the limit of allowable space.
Greg

[KevinBarrett]

Thank you, Greg, it's very enlightening to have all the numbers in front of you.

[Heidfirst]

Not all the SAM lenses are expensive though..
Sony 55-200 f4-5.6 DT SAM 305g (L85 X W72mm) $230 US B&H
Sigma 50-200 f4-5.6 DC OS HSM 420g (L101.9 X W74mm) $199 US B&H (both have 55mm filter size)
....an amazing price for Sony....

Sony 18-55 f3.5-5.6 DT SAM 210g (L70 X W70mm) $200 US B&H
Sigma 18-50 f2.8-4.5 DC OS HSM 395g (L74 X W88.6mm) $199 US B&H (The Sigma is physically larger because of the large starting aperture, has 67mm filter vs 55mm for the Sony lens).
....although a slower lens it's another amazing price from Sony....
Greg

note that both the Sigmas that you mention have optical stabilisation built-in as well ...
You would need to compare a non-OS version to the Sonys for a true comparison.

the Tamron 55-200 is $165 delivered at B&H so you are paying $65 (40% of selling price) for a micromotor & a different name.