Swapping Tamron 70-300 for Sigma APO

moxfyre · 03-31-2008, 01:39 PM

Originally posted by kenyee

Looks like a good copy to me :-)
If you stop it down enough (roughly 2 stops), the PF is mostly controlled.
Be careful about the evil rear lens cap...

What's evil about the rear cap on the Tamron? It's much sturdier than the cheap rubber ones that I've seen on other lenses.

benjikan · 03-31-2008, 02:35 PM

Originally posted by kenyee

Looks like a good copy to me :-)
If you stop it down enough (roughly 2 stops), the PF is mostly controlled.
Be careful about the evil rear lens cap...

My lens cap has the dot point well indicated in relief...

kenyee · 03-31-2008, 03:50 PM

Originally posted by moxfyre

What's evil about the rear cap on the Tamron? It's much sturdier than the cheap rubber ones that I've seen on other lenses.

If you're switching lenses and do the technique where you put the rear lens cap back on your Tamron w/o matching up the dots and just rotate it clockwise until it drops down (I put the Tamron in my Velocity bag while doing this), it can drop down into a misaligned position where the rear cap is locked on and you can't get it off...

My Sigma 17-70's cap has no such problem. It's a fairly common problem. I've seen this in the Canon and Nikon forums as well from other Tamron owners (google for "Tamron stuck rear lens cap" if you're curious)...
Even lens rental places know about it. A friend rented a few Tamron lenses and both had their caps replaced w/ Nikon ones :-)

moxfyre · 04-01-2008, 12:36 AM

Originally posted by kenyee

If you're switching lenses and do the technique where you put the rear lens cap back on your Tamron w/o matching up the dots and just rotate it clockwise until it drops down (I put the Tamron in my Velocity bag while doing this), it can drop down into a misaligned position where the rear cap is locked on and you can't get it off...

My Sigma 17-70's cap has no such problem. It's a fairly common problem. I've seen this in the Canon and Nikon forums as well from other Tamron owners (google for "Tamron stuck rear lens cap" if you're curious)...
Even lens rental places know about it. A friend rented a few Tamron lenses and both had their caps replaced w/ Nikon ones :-)

Hmm... I haven't encountered this problem myself, somehow. I'll keep an eye out for it. Thanks!

By the way, I just got some new rear lens caps from CameraFilters.com (along with a hood, front caps, polarizer, other odds and ends). Their plastic twist-on K-mount caps are only about $1 and work very nicely.

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03-31-2008, 01:39 PM	#16
moxfyre Forum Member Join Date: Mar 2008 Location: College Park, MD Posts: 86	Originally posted by kenyee Looks like a good copy to me :-) If you stop it down enough (roughly 2 stops), the PF is mostly controlled. Be careful about the evil rear lens cap... What's evil about the rear cap on the Tamron? It's much sturdier than the cheap rubber ones that I've seen on other lenses.

03-31-2008, 02:35 PM	#17
benjikan Veteran Member Join Date: Jan 2007 Location: Paris, France Photos: Gallery Posts: 4,308	Originally posted by kenyee Looks like a good copy to me :-) If you stop it down enough (roughly 2 stops), the PF is mostly controlled. Be careful about the evil rear lens cap... My lens cap has the dot point well indicated in relief...

03-31-2008, 03:50 PM	#18
kenyee Veteran Member Join Date: Mar 2007 Location: Boston, PRofMA Photos: Albums Posts: 3,026	Originally posted by moxfyre What's evil about the rear cap on the Tamron? It's much sturdier than the cheap rubber ones that I've seen on other lenses. If you're switching lenses and do the technique where you put the rear lens cap back on your Tamron w/o matching up the dots and just rotate it clockwise until it drops down (I put the Tamron in my Velocity bag while doing this), it can drop down into a misaligned position where the rear cap is locked on and you can't get it off... My Sigma 17-70's cap has no such problem. It's a fairly common problem. I've seen this in the Canon and Nikon forums as well from other Tamron owners (google for "Tamron stuck rear lens cap" if you're curious)... Even lens rental places know about it. A friend rented a few Tamron lenses and both had their caps replaced w/ Nikon ones :-)

04-01-2008, 12:36 AM	#19
moxfyre Forum Member Join Date: Mar 2008 Location: College Park, MD Posts: 86	Originally posted by kenyee If you're switching lenses and do the technique where you put the rear lens cap back on your Tamron w/o matching up the dots and just rotate it clockwise until it drops down (I put the Tamron in my Velocity bag while doing this), it can drop down into a misaligned position where the rear cap is locked on and you can't get it off... My Sigma 17-70's cap has no such problem. It's a fairly common problem. I've seen this in the Canon and Nikon forums as well from other Tamron owners (google for "Tamron stuck rear lens cap" if you're curious)... Even lens rental places know about it. A friend rented a few Tamron lenses and both had their caps replaced w/ Nikon ones :-) Hmm... I haven't encountered this problem myself, somehow. I'll keep an eye out for it. Thanks! By the way, I just got some new rear lens caps from CameraFilters.com (along with a hood, front caps, polarizer, other odds and ends). Their plastic twist-on K-mount caps are only about $1 and work very nicely.