tesseagles Loc: NW ARKANSAS OZARKS

An anyone tell me what this button on my Sigma zoom lens is for? I know the auto manual switch. It’s the one below it . THE OS ON AND OFF SWITCH! What is that for? Thanks!!

CHG_CANON Loc: the Windy City

Did you try checking the manual?

Silverman Loc: Michigan

Would that possibly be for Vibration reduction?

jeep_daddy Loc: Prescott AZ

tesseagles Loc: NW ARKANSAS OZARKS

Had I not purchased this lens used and without a manual yes I certainly would have looked it up, read it, and had my answer.
But because I have no manual, and I have this great group of photographers who have been great help I thought “I know!! I’ll ask on uglyhedgehog!” And viola I got my answer and I thank you very much for sharing your knowledge.

CHG_CANON Loc: the Windy City

Try the manufacturer's website. Many times, the PDF copies of all their manuals are available for free download, lenses, cameras, etc.

tesseagles Loc: NW ARKANSAS OZARKS

I have for my camera which I bought used but for the lens I figured I’d a quick answer since I know pretty much the rest of the lens and how to use it. This was puzzling me. I sure appreciate your help!!
Tess🌸

tesseagles Loc: NW ARKANSAS OZARKS

I have for my camera which I bought used but for the lens I figured I’d a quick answer since I know pretty much the rest of the lens and how to use it. This was puzzling me. I sure appreciate your help!!
Tess🌸

billnikon Loc: Pennsylvania/Ohio/Florida/Maui/Oregon/Vermont

After using both 1 and 2 you must bucket your shoe.
NO, one is for general vibration reduction and 2 is for sports.

ggab Loc: ?

Recent mfg Tele Zoom lens that have stabilization, now often provide an option for panning vs shooting stationary objects.
You will see this on the Manufacturers lenses as well as third party, Tamron and Sigma.
Which Sigma lens is yours?

47greyfox Loc: on the edge of the Colorado front range

I’ll second the recommendation to check the website for Sigma lens info. The “manual” supplied with lens is usually a multi language big folded piece of paper that requires a powerful set of reading glasses to find information.

nadelewitz Loc: Ithaca NY

That's another name for Optical Stabilization.

amfoto1 Loc: San Jose, Calif. USA

Yes, it's image stabilization, to help you hand hold steady shots at slower shutter speeds than would normally be possible. Sigma calls it "OS" or "optical stabilization". When it's enabled, there are sensors within the lens that detect any movement and shift a group of lens elements to counteract "camera shake" blur.

Typically you can use three to four stops slower shutter speed with a stabilized lens, than would be possible without it. For example, a 200mm focal length without stabilization might normally need at least 1/200 shutter speed. One stop slower is 1/100. With reasonable care and good technique you should get a very high percentage of sharp shots. Two stops would be 1/50 shutter speed and you still should see very good results. Three stops is 1/25, but most shots will still be sharp so long as you are reasonably steady. And even 1/12.... four full stops slower... might be possible at 200mm. (If you are using an APS-C camera, 200mm "acts like 300mm".... so the numbers might instead be 1/300, 1/150, 1/75 and 1/37.)

The manual and previous responses are correct about the two different stabilization modes, too. Just to clarify, Mode 1 is "normal". The stabilization works to correct movement in all directions, both on the horizontal axis and vertical axis. Mode 2 might best be described as a "panning mode", often used for sports but possibly used for other things, too. Anything that's moving can be panned. "Panning" is done using a slower shutter speed (called "dragging the shutter") to deliberately introduce some background and/or foreground blur effect and lend a sense of movement to an image, while still rendering the moving subject reasonably sharp.

Mode 2 image stabilization only corrects movement along one axis.... the vertical. It doesn't try to counteract the blur that you're trying to introduce with the panning technique.

Below is an image that was done using a panning technique and slower shutter (note: take extra shots... panning can be tricky and only a limited percentage of the shots are likely to come out the way you envision them). This image was done at 1/80 with a 200mm lens on an APS-C camera...



Compare to the below image that was done without the panning technique, using a much faster shutter speed to fully freeze the subject's movement (note the difference in how the car's wheels appear, in addition to both foreground and background objects)... In this case, a 300mm lens and a 1/3200 shutter speed:



Both above shots were done with lenses that have image stabilization and were on identical cameras (Canon 50D, APS-C format).

Panning while dragging the shutter versus a fast shutter to freeze movement are two different ways to render moving subjects in a still photo.... It might be "sports" in these examples and many other cases, but certainly isn't limited to only those types of subjects. You can choose how you want to render any moving subject. A third possibility is to use a stationary camera... no panning... along with a slower shutter speed, to allow movement to blur. I don't have an example to show you... but you've surely seen images where flowing water or surf is made to look "creamy", while all the stationary objects in the image appear sharp. That's done using a long shutter speed, but usually with the camera on a tripod so there's no panning or other movement at all.

Hope this helps!

cambriaman Loc: Central CA Coast

OS is the Sigma term for VR.

nadelewitz Loc: Ithaca NY

VR=OS=IS=on and on. Every camera maker has to give it their own name.