what could be wrong with this lens??

[ottor]

Purchased a "Used - New Condition" Sigma 70-200 f/2.8 OS EX DG APO from Amazon - seller is a private party.. Stated used it for a week or so and wanted to sell to trade for a Canon lens.

Using on a Canon 450D - when I use "Live View", the autofocus will lock, and then on the LCD, it appears that the image will 'float' to the left of the screen, and then float back slowly again... He sent me the warranty card that was never filled out. Is this something I should send back to Sigma, or has anyone else seen this before? The "Proof of purchase" will show that it was purchased 'used', but I completed the warranty card - do you see any problems with any warranty work that may be done?

tks,

r

 

[Derrel]

I have not heard of this issue. It sounds as if it might be something with the OS system. Have you cross-checked it with the OS on,and with it Off, to see if that is the root of the problem?

How fast is the refresh rate of the camera?? Is it possible that the OS system and the refresh rate of the Live View, together, cause some type of delay?

I am not familiar with that camera. Do you have other image stabilizer lenses, like a Canon made one, for comparison?

 

[ottor]

I have not heard of this issue. It sounds as if it might be something with the OS system. Have you cross-checked it with the OS on,and with it Off, to see if that is the root of the problem?

How fast is the refresh rate of the camera?? Is it possible that the OS system and the refresh rate of the Live View, together, cause some type of delay?

I am not familiar with that camera. Do you have other image stabilizer lenses, like a Canon made one, for comparison?

>>>>>>>>>>>>>>>>>>

Thanks Derrel...

I put my 18-55 IS Canon on, and with the IS on/off, no problem... has always worked perfect.

The sigma has 2 OS Modes - and I'm not sure what the difference of the modes are... The Sigma Manual states... "Set the OS switch to Mode 1 - press the shutter button 1/2way down, confirm the image in the viewfinder is stable then take the pic. (It takes about 1 second to produce a stable image) - Mode 2 detects the vertical camera shake, and overcomes the blurring. It is effective on subjects moving horizontal to the camera"

I put the Sigma back on, and with the OS #1 off - no shift - turned it on, and image shifted to the left .. Mode #2 was stable in the viewfinder.

Although I'd never shoot with the OS on while attached to a tripod, I tried it this time, and used a wired remote shutter release so I know that it's not a 'handling' thing.. .. The image in live view mode was totally stable.... Turned on the OS, pushed the button 1/2way to focus, and the image shifted to the left again.. slowly, but steady.

Odd... I'd hate to return this (If I even can) when it's either normal, or it's my mistake...

r

 

[Derrel]

Well, you know, after your explanation, it sounds like this is normal behavior. That 1-second time period required to produce a stable image...seems like that's being represented on the Live View...

 

[KmH]

Mode 2 is for panning. The OS system ignores the horizontal accelerometer.

I hate to be the bearer of bad news, but Sigma's warranty, like the warranty from virtually all other consumer electronics makers, only applies to the original owner and is not transferable.

Sigma has online warranty registration, so few people ever bother to fill in the warranty card. Sigma - Service - Register your new Sigma