To IS...or NOT to IS....

Skip, save your money. If it was an extra $100 then go for it but the extra cost of 5 to $600, no.

Depends. I do a lot of low light work and I don't believe I ever shoot at more than 1/125.. if I am shooting higher than that I drop the ISO. So personally I'm aiming for the IS version so I can keep my nice shutter speeds without having to up the ISO.

If you do a lot of sunny, outdoors stuff the difference may not be worth it.

How about reliability? What happens after the warranty runs out and the IS stuff breaks, or it gets out of alignment? How much does it cost to have it repaired/replaced?
I think it would be much cheeper to have a non-IS lens calibrated than a IS lens rebuilt/calibrated. This is what drove Me to get the non-IS F4.

Sam

IS DOES matters. Get it !

If you always think on the "Murphy-line", yes, don't buy a IS lens.
If you think real life - IS is highly recommended!!!
Save good shots - IS it's worth of it.
Going cheap - o.k. - Your choice.
Hey, btw, it's a great workout to carry an IS lens on a field trip, consider the weight loss to the purchase, it's a win-win situation....

ChrisBlaze wrote in post #2236600
does the "in body" IS from people like Sony suppose to stop motion blur?

No. It does the same thing as an in-lens IS system, albeit not as efficiently.

You will NEVER regret spending the extra for IS.

I have never wished I had a no IS when I was using an IS lens. If you don't need IS you just turn it off.

There have been several times when I wished I had IS when I was using a non-IS lens. You cannot add IS as an after-market option to a non-IS lens.

If you are ever going to be hand holding the lens in a low light situation where you really want the shot, get the IS version. The difference in cost depends on how much you value your difficult shots.

AirBrontosaurus wrote in post #2234523
IS doesn't stop motion blur. It stops camera shake. If you can shoot in the conditions you want and like the results, then you don't need IS. If you constantly find yourself sufferering from camera shake blur or using too high ISO, then you should look into IS. It won't stop motion blur (which means it has limited usefulness for stoppping motion with sports), but it will help make the background look crisper.

I think this is the perfect answer.

I got my "main" lens (17-55) with IS, because I use it frequently indoors, and outdoors with low light, and with an ISO of about 400 and the IS turned on I can do pretty much anything I want. I also got the IS on my 70-300, but have it turned off most of the time because when I use that lens, I am on a tripod.

If you currently like your non-IS pictures, I'd advise you don't bother spending the money on it. Firther, if you are using a lens that you really like, I'd say go ahead and get your own since you already know what to expect and that it works well for you. You're already way ahead of the game on this one. Get your own copy of the Sigma (or just see how long you can keep borrowing that one )

Go to a shop and try both lenses on. Have a look at 200mm with shutter speeds below 200 with and without IS and you can see the diff.

I'm getting old and starting to get the shakes...

But even with your camera mounted on a tripod.... Nothing is rock solid. Can still get loss of IQ. IS does help, especially those newer IS that are tripod sensitive.

Well a lot my photofrapher friends that used to shot events at night all they purcased IS lenses and couple of weeks later slod theyre IS lenses

they said IS didnt done much difrence to them and that is loses sharpness

so id say go for the sigma ... want low shuter speed ? buy a good tripod or monopod

i've never used a IS lens so im no thalking by own experience but from other experince

( anyway all this is my opinion and im n00b xD )

IS does make a big difference when it comes to camera movement...well worth the money if you have poor technique or get tired from holding position for an extended period of time. For many people, IS does make a big difference. I have IS on most of my lenses and have yet to find a situation where I wished I didn't have it. I can not say the same for my non-IS lenses...there have been many times that I wish they did have IS.

I agree with the "you'll never regret IS" posters.
I think its important to remember IS requires a slight change in technique too - it takes a fraction of a second to kick in. Many that I've heard say "it made no difference" were sports shooters who don't have the option of holding the shutter button for half a second for the IS to stabilize. For them it may not matter. For me with my less than perfect tecnhique and caffeine saturated hands, it does.

If money isn't a problem and go with the IS. You won't regret it.

Good luck.