Sigma 150-600 Sports/Contemporary Firmware Update for Faster AF

Firmware seems to have been released to improve AF speeds 20-50%, please report your findings!

http://www.sigma-global.com …il/150_600_5_63​_S014.html

Having moved house three weeks ago my dock is still hiding in one of the boxes that is as yet unpacked. Will try to find it and see how things go. As I now have open fields all around my new place it seems the perfect time to do a bit of bird photography. We think we have at least four songbird nests in the hedge around our gardens, including possibly a Robin.

Alan

AF seems snappier, but I still get that "Sigma jitter", where the AF ratchets a little bit. Sometimes I get it, sometimes I don't.

TeamSpeed wrote in post #17932652
AF seems snappier, but I still get that "Sigma jitter", where the AF ratchets a little bit. Sometimes I get it, sometimes I don't.

What is the "Sigma jitter" ? Never heard of it.

In AI Servo while shooting seemingly stationary subjects while holding down AF ON, Sigma lenses can jitter back and forth. I don't get this with my Canon USM lenses. Very minute adjustments back and forth... It is as if the lens and body argue a bit. It's not a body thing, I have seen this on several bodies with a few of my Sigmas. Sometimes they just lock and don't move, other times meh.

Well I found the dock and the update is done. The AF is now really snappy, definitely quicker than it used to be. This is the first time I have really seriously tried it out on static targets like this, but I did notice a little bit of jitter with BBF/AI Servo. My other Sigma lenses are not HSM, I have had it once or twice only with my 20-40 EX DG f/2.8 but never noticed it on the cheap 28-300. I'm shooting on a 50D.

I shot a few hand held out of my bedroom window of one of the local Robins, through the double glazing. Focus looks OK but they all look a bit soft on the camera LCD at max zoom. Two panes of window glass will do that though. Time to get the bedroom furniture arranged so I can set the camera up on the tripod and open the window in order to shoot.

Alan

Oh something else I noticed after downloading the test shots I did is that the lens description has changed in LR, I'm still using LR4.4. Instead of just having the focal length it is showing the full makers name and model designation.

Haven't had the chance to use it on anything challenging, but the little bit of testing I have been able to do makes me real anxious for some time off to go test it on some small birds or birds in flight. The lens really snaps to focus, although I do understand what you are calling "Sigma jitter".

Tim

This is firmware version 1.02 for the Contemporary Lens, and version 1.04 for the Sports lens..... just to clarify. I just updated my 150-600 C, will take it out over the weekend and see if I can tell a difference in the AF speeds! May also throw on the Canon 1.4TC v2 and see how the AF speed is with that combo now.

TeamSpeed wrote in post #17932652
AF seems snappier, but I still get that "Sigma jitter", where the AF ratchets a little bit. Sometimes I get it, sometimes I don't.

"Sigma jitter" boy that's a new one! My S doesn't "jitter" and I have never even heard of that phrase.

You have never heard of the term jitter? It is a very common technical term in electronics.

I've experienced jitter with canon lenses.

TeamSpeed wrote in post #17932681
In AI Servo while shooting seemingly stationary subjects while holding down AF ON, Sigma lenses can jitter back and forth. I don't get this with my Canon USM lenses. Very minute adjustments back and forth... It is as if the lens and body argue a bit. It's not a body thing, I have seen this on several bodies with a few of my Sigmas. Sometimes they just lock and don't move, other times meh.

All of my Canon lenses jitter, including 300mmf/2.8, 100mm macro (possibly the worst), 15mm Fisheye (another bad one), and 17-40mm. The lens that does it the least is the 24-105mm L. It doesn't matter the body either. The jitter occurs with 3 different 1 series bodies and the 7D MkII. Chuck Westfall has written that this is normal in AI Servo.

I don't believe the ratcheting is normal. I have had sigma do this on a 1d3 but canon lenses didn't. After the the 1d3 was sent in for their mirror box recall, the sigma stopped doing it. Then my 1d4 had the same issues. I have not seen this with canon late model lenses. There is something amiss in AF communications, tolerances, etc. I have seen this with older canon lenses too, but not with any of the mkii lenses. Often when a manufacturer knows something is a little off, will they call it normal. It is a common joke in the software industry to call a long lasting and known software bug a "feature". It just means that either a solution isn't known yet or the fix hasn't been prioritized.

http://www.dictionary.​com/browse/jitter
verb (used without object)
3. to behave nervously.

I'd say that's a good match for the described lens "feature"

I have found a common way to experience jitter is fitting an extension tube (and even more so if teleconverter also fitted) to a lens and attempting to AF. My 100-400 II will do it with all 3 bodies I own but is well behaved without the tube.

It is definitely a combined lens/camera behavior. It is almost like the camera body tells the lens to focus to X, the lens tries, but doesn't have enough finely graduated gearing to quite get there, and goes too far, the camera says, whoa, back up a bit, and the lens goes back, but again focus is not quite right yet again, and it gets into this twitchy sequence.

I have seen some sigma and canon lenses on some bodies that in AI Servo, don't do this either. I haven't quite nailed down the conditions or combinations, but it does affect my shooting from time to time.

AI Servo should remain locked on a non-moving target without creating a situation where you run a burst as it does this jitter, causing a number of OOF images. You shouldn't have to go to One Shot with still objects. You never know when that bird is going to launch off a branch.