Tamron SP 150-600mm Di VC USD

archer1960 wrote in post #16704213
I have seen this exact same thing with other long 3rd-party lenses; the Sigma 50-500 (which I have rented multiple times) does it occasionally too, as does my Tamron 18-270.

Is your 18-270 the newer model with the PZD motor? I have the earlier version, and have never had this happen to me.

Digital EOS 7D Mark II Canon: EF 50mm f/1.8 II, EF 50mm f/2.5 Compact Macro, Life-Size Converter EF Tamron: SP 17-50mm f/2.8 DiII, 18-400mm f/3.5-6.3 DiII VC HLD, SP 150-600 f/5-6.3 Di VC USD G2, SP 70-200 f/2.8 Di VC USD, 10-24mm f/3.5-4.5 DiII VC HLD Sigma: 30mm f/1.4 DC Art Rokinon: 8mm f/3.5 AS IF UMC

pknight wrote in post #16704740
Is your 18-270 the newer model with the PZD motor? I have the earlier version, and have never had this happen to me.

No, it's the older version. It doesn't happen often, but when I heard that it was also happening with the 150-600, I just figured it was something in the way Tamron reverse engineered the Canon AF system. Just moving the camera to a different subject and back, or changing the zoom level will bring it back to life.

Gripped 7D, gripped, full-spectrum modfied T1i (500D), SX50HS, A2E film body, Tamzooka (150-600), Tamron 90mm/2.8 VC (ver 2), Tamron 18-270 VC, Canon FD 100 f/4.0 macro, Canon 24-105 f/4L,Canon EF 200 f/2.8LII, Canon 85 f/1.8, Tamron Adaptall 2 90mmf/2.5 Macro, Tokina 11-16, Canon EX-430 flash, Vivitar DF-383 flash, Astro-Tech AT6RC and Celestron NexStar 102 GT telescopes, various other semi-crappy manual lenses and stuff.

palmor wrote in post #16696985
Canon EOS 5D Mark III
1/3200s f/8.0 at 600.0mm iso640

Nice... I wish the BG was blue sky. Would make for a great print.

A7rIII | A7III | 12-24 F4 | 16-35 GM | 28-75 2.8 | 100-400 GM | 12mm 2.8 Fisheye | 35mm 2.8 | 85mm 1.8 | 35A | 85A | 200mm L F2 IS | MC-11
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archer1960 wrote in post #16704767
No, it's the older version. It doesn't happen often, but when I heard that it was also happening with the 150-600, I just figured it was something in the way Tamron reverse engineered the Canon AF system. Just moving the camera to a different subject and back, or changing the zoom level will bring it back to life.

The difference is, at least for those of us with a lens exhibiting this behavior, it isn't "occasionally". It's 100% reproducible; and it's quite odd behavior.

My 18-270 won't do the same thing no matter how hard I try.

That said, when my camera guy gets back from his trip, I'm gonna have him send it to Tamron for a looksee; and see what they say.

EDIT: To be clear, it's when moving suddenly between a near or far target that's in focus, to a target in the opposite direction that is not. This is not failure to acquire and track something like a BiF nor AF failing period.

- Eric S.: My Birds/Wildlife (7D MkII/5D IV, Canon 10-22 f/3.5-4.5, Canon 24-105L f/4 IS, Canon 70-200L f/2.8 IS MkII, Canon 100-400L f/4.5-5.6 IS I/II)
"The easiest way to improve your photos is to adjust the loose nut between the shutter release and the ground."

Snydremark wrote in post #16704822
The difference is, at least for those of us with a lens exhibiting this behavior, it isn't "occasionally". It's 100% reproducible; and it's quite odd behavior.

My 18-270 won't do the same thing no matter how hard I try.

That said, when my camera guy gets back from his trip, I'm gonna have him send it to Tamron for a looksee; and see what they say.

EDIT: To be clear, it's when moving suddenly between a near or far target that's in focus, to a target in the opposite direction that is not. This is not failure to acquire and track something like a BiF nor AF failing period.

Ok. I can't reproduce it reliably on my 18-270, but it's always at max zoom when it does happen. I've got a tamzooka on the way, hopefully in the next two weeks or so, and I'll play with it when it gets here.

Gripped 7D, gripped, full-spectrum modfied T1i (500D), SX50HS, A2E film body, Tamzooka (150-600), Tamron 90mm/2.8 VC (ver 2), Tamron 18-270 VC, Canon FD 100 f/4.0 macro, Canon 24-105 f/4L,Canon EF 200 f/2.8LII, Canon 85 f/1.8, Tamron Adaptall 2 90mmf/2.5 Macro, Tokina 11-16, Canon EX-430 flash, Vivitar DF-383 flash, Astro-Tech AT6RC and Celestron NexStar 102 GT telescopes, various other semi-crappy manual lenses and stuff.

Sam
5D4 | 6D | 7D2 (2 bodies) | Reasonably good glass
Gear List
If I don't get the shots I want with the gear I have, the only optics I need to examine is the mirror on the bathroom wall. The root cause will be there.

Scrumhalf wrote in post #16704937
Doesn't seem to happen to this guy, whatever the reason is. And he is using a 7D.

http://www.youtube.com​/watch?v=I6BXbjSywY4

He's not using AI Servo. He's using One Shot and moving the focus point in between shots; totally different scenario. I've never seen One Shot fail to go grab focus yet.

- Eric S.: My Birds/Wildlife (7D MkII/5D IV, Canon 10-22 f/3.5-4.5, Canon 24-105L f/4 IS, Canon 70-200L f/2.8 IS MkII, Canon 100-400L f/4.5-5.6 IS I/II)
"The easiest way to improve your photos is to adjust the loose nut between the shutter release and the ground."

Sam
5D4 | 6D | 7D2 (2 bodies) | Reasonably good glass
Gear List
If I don't get the shots I want with the gear I have, the only optics I need to examine is the mirror on the bathroom wall. The root cause will be there.

Grizz wrote in post #16704733
Hawk with dinner.

IMAGE LINK: http://flic.kr/p/ki1jJ​x

Wow!

6D | 70D | 24-105 L IS | 17-40 L | 300 F4 L IS | 50 1.8 II | 1.4x II | LR5 | HV30 | bug spray | wilderness
Gallatin National Forest, Montana/Lassen Volcanic NP Campgrounds

Peter
http://www.flickriver.​com/photos/peterbangay​an
EOS 5D Mark IV, 1Dx1, 7D Mark I & II/Canon T2i Gripped/EF 500mm f/4L IS USM MK1 / EF70-200mm f2.8L IS II USM / EF100 -400 f4.5-5.6L USM/ EFS 10-22mm/EFS 17-55mm/EFS 18-200mm/Canon 1.4x II/Canon 2x III/ 430EXII / 580EXII.

Randy
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-JasonMK on Flickr
1Ds Mark III | 650D | EF 17~40mm 4L | EF-S 18~135 STM | EF 50mm 1.4 | EF 100mm 2.8 USM Macro | Tamron 70~300mm 4.0-5.6 Di VC USD XLD | 430 EX III | 430 EX II | Lowepro SlingShot 100 AW | EF 25 II | PS CC | LR CC

My Flickr page - https://www.flickr.com​/photos/86957042@N07/

Absolutely agree there, Randy. Just to further the discussion: (be sure to click through to see better quality)

7D + 100-400; 400mm @ f/8:

IMAGE LINK: http://www.flickr.com …s/snydremark/12​666332714/
Reifel Sandhills_400-0673 by Guideon72, on Flickr

7D + Tamron 150-600; 400mm @ f/6.3:

IMAGE LINK: http://www.flickr.com …s/snydremark/12​665877265/
Reifel SHCrane-0395 by Guideon72, on Flickr

Plus a whole post on my recent trip to a local reserve (where the cranes were taken):
https://photography-on-the.net …/showthread.php​?t=1361905

This lens performs remarkably well, especially for the price range and reach.

- Eric S.: My Birds/Wildlife (7D MkII/5D IV, Canon 10-22 f/3.5-4.5, Canon 24-105L f/4 IS, Canon 70-200L f/2.8 IS MkII, Canon 100-400L f/4.5-5.6 IS I/II)
"The easiest way to improve your photos is to adjust the loose nut between the shutter release and the ground."

- Eric S.: My Birds/Wildlife (7D MkII/5D IV, Canon 10-22 f/3.5-4.5, Canon 24-105L f/4 IS, Canon 70-200L f/2.8 IS MkII, Canon 100-400L f/4.5-5.6 IS I/II)
"The easiest way to improve your photos is to adjust the loose nut between the shutter release and the ground."