Focus Issue

[Swampy]

Ok, I'll start with the first Canon thread. I can't understand what's happening with my Canon version Sigma 50-500mm.

When I first got it, I couldn't get a picture in focus to save me, then I went on my Mexico trip 2 days later without having much time with it. I'm shooting down there with it. Out of focus. Almost like a backfocus issue. A few days into my vacation and I dare bring it out again. I shot wonderfully sharp pictures of pelicans and seagulls on the water that I posted up not long ago (Photos - Color - Pelican Case). After that, again, everything out of focus. I figured it to be a backfocus issue this morning. I took shots in AF and could see it was OOF in the viewfinder even, turn the focus a little bit and took the same shot, tripod, selftimer, mirror lockup. Manual focus worked fine, AF - blurry. Tried a bunch of different types of shots. Always the same. It's not the camera though. Both my Canon's do it and my other lens works fine on both cameras.

So. I guess I send it back for repair already. I'm still curious, why would it not work, then work, then not work again? Odd.

[Wichita Wayne]

Have you considered the level of charge remaining in the batteries? If your sharp shots were on fresh batteries then you might just need to change batteries when you want to use this lens. It is a big lens that probably needs good steady power to drive its motors. I would also contact Sigma. This lens is one of their high dollar flagships and I am sure that they want you to get better service. Lastly........just how much Mexican hooch did you drink before taking the out of focus pictures?

[Swampy]

Have you considered the level of charge remaining in the batteries? If your sharp shots were on fresh batteries then you might just need to change batteries when you want to use this lens. It is a big lens that probably needs good steady power to drive its motors. I would also contact Sigma. This lens is one of their high dollar flagships and I am sure that they want you to get better service. Lastly........just how much Mexican hooch did you drink before taking the out of focus pictures?

Battery indicators say "full" and it's not like the S2's indicators (either full or hey, you're going to lose pictures now). If it takes that much juice to drive this lens, then I don't want it in Canon. But I doubt that's it. I've got about 100 pictures on the charge of this battery and it's supposed to be good for 1500 shots or so. This happened with the first shots I took, then on the same charge a few days later, it worked perfect, and now, it's still doing it.

Haven't contacted Sigma, will be doing that tomorrow. Yesterday was the first time I had a chance to really investigate the issue.

No hooch down in mexico before any of the pictures with that lens... :)

[Linda G]

It does definitely sound like a lens problem. It may not be getting power from the camera connections right. Canon lenses have their own motors, unlike other camera models and if the connectors aren't making good contact or your power supply irratic, that could explain your problems. As new as it is, I'd send it back and explain the problem but make sure it's happening on both your canons, not just one. Don't want sigma to tell you it's your camera. <g>

[fujifilmnut]

Had this a long time ago on a Nikon F4 and Vivitar lens. It was a loose lens element.

[Auminer]

Please update us on what you found out...I'm having the same problem on the D2x with the 50-500. Was going to check it out on the S2, but I'm getting a black CCD death on that one now! :mad: Ruined a lot of shots I thought were going to be winners...grrrrrrr.

Dave