Photoclubalpha

For a mate who is thinking about this lens, has anyone got/used one on Sony or other makes (he actually has N***n).
Any comments/samples welcome.

I'm holding out for the Sony 70-400!

Mike

Yes, we've had one on Nikon full frame D3. It is really excellent, much better than earlier Sigma designs of a similar range, and the OS works well. Not that the Sony version has OS.

David

David Kilpatrick wrote:Not that the Sony version has OS.

I heard the rumour that Sigma is planning to sell their OS lenses also in Sony Alpha and Pentax K mounts---with OS! Currently, their OS lenses for cameras that have in-body image stabilizers built in are without OS. But obviously this is going to change. So in the near future, Sony and Pentax shooters using Sigma OS lenses will be able to choose between in-body and in-lens stabilization. Of course the two stabilizers won't co-operate so the user must decide for one and switch off the other.

The rumour so far refers to the brand-new Sigma 18-250 mm 1:3.5-6.3 DC OS HSM lens only. I have no idea if more Sigma OS lenses for Sony and Pentax will follow ...

-- Olaf

I'm awaiting a response from Sigma UK on this. Their MD is insistent that the Hybrid OS will switch automatically, using OS for viewing and SSS for exposure. Their technical sales manager is not so sure, he's waiting for a firm statement on how this will work.

David

I would be keen to learn more about the functioning of this lens. I have been put off a little by the 1,750 Kg weight. I would like to know if it has lens stabilisation for Alpha that can be switched off or if this has been completely disabled for the Alpha mount. Based on O1af's insert above in lens image stabilization appears to have been switched off in the Alpha mount 120-400. Can that be confirmed? I wonder if the lens has crept up to 1,750 Kg because it has been made as the Canon/Nikon but just with OS switched off.

While it may make manufacturing easier to put the image stabilization into all lens mounts, one of the reasons I bought into Sony was so that I didn't have to pay more for stabilized lenses, nor put up with the extra bulk and weight.

And I REALLY hate to pay for useless features!

Dusty

alphaomega wrote:I would be keen to learn more about the functioning of this lens. I have been put off a little by the 1,750 Kg weight. I would like to know if it has lens stabilisation for Alpha that can be switched off or if this has been completely disabled for the Alpha mount. Based on O1af's insert above in lens image stabilization appears to have been switched off in the Alpha mount 120-400. Can that be confirmed? I wonder if the lens has crept up to 1,750 Kg because it has been made as the Canon/Nikon but just with OS switched off.

The OS is absent. It is built without it for Sony and Pentax.

David

i'll bet the only weight numbers they publish are for the OS versions only, even if the Pentony versions are lighter. would that make canon or nikon users upset if the lens was lighter for the body AS mounts? or make them take notice of it and investigate further as to why? or maybe just find out there is no as on these brands? it would just create confusion i'm sure

David Kilpatrick wrote: The OS is absent. It is built without it for Sony and Pentax.

David

But will we see real reductions in weight/size/cost, or just a big fat expensive OS lens with the OS turned off?

Dusty

It is exactly the same in dimensions, but not in weight. The weight quoted refers to the Nikon mount model only, always, with Sigma specs.

David

is there any indication yet on the effect these elctromechanical parts have on how long a lens lasts ? For example what happens when one of hese lens OS systems goes bad is it like body AS where the sensor can be shifted?

Javelin wrote:is there any indication yet on the effect these elctromechanical parts have on how long a lens lasts ? For example what happens when one of hese lens OS systems goes bad is it like body AS where the sensor can be shifted?

There have been failures already. Also, these lenses depend on accurate parking of the moving group for their best (non-stabilised) performance. All of them give uneven sharpness across the frame when the OS/IS/VR/VC is used, unlike in-body stabilisation. This is hardly visible with long teles but shows up with a vengeance in designs like the Canon 24-105mm K, Nikon 24-120mm, etc when used at the wide end. If the moving group is incorrectly centered when parked, then even the unstabilised performance of the lens suffers. This has been the big problem with the 105mm VR Nikkor macro lens, the VR mechanism causes vignetting (unevenly distributed) and does not park centrally, so when turned off, the use may be left with uneven and quite sharp corner vignetting and sharpness loss.

All of this is ignored by those who claim in-lens OS beats in-body. It may do so for long lenses, where the field of view and circle of coverage allow loads of tolerance. It's not the case with wide and wide to tele zooms though, and it would be a disaster with fast wides. No IS/VR type 35mm f1.4 or anything like it has ever been made - the macro Nikkor is the closest and that is considered to have suffered badly from the VR installation.

David

I knew about the problems it causes on some focal lengths. I just wonder what those lens will be like in 20 years.

I have long had this lens in my sight, but held back due to the published weight. I note DK is stating above that the Sony version is lighter than the published 1,750 Kg. I once asked Sigma if they could provide me with the Sony version weight. They stated they had just received supplies but not yet put a copy on their scales. They never came back on it.
I would be most grateful if an owner or a person "in the know" could state the actual weight of the Sony version here. thanks in advance.

They don't know yet so nor do I!

It is only likely to be a few grammes difference. Have you found out whether the Sony is HSM or screw drive? If it is HSM, the weight will be very close. If it is screw drive, that may cut 100g or more from the weight.

There is no way it is going to be significantly lighter, 10 per cent maybe.

David