Go Back   Steve's Digicams Forums > Digital SLR and Interchangeable Lens Cameras > Canon Lenses

Reply
 
Thread Tools Search this Thread
Old Apr 23, 2007, 9:07 PM   #1
Junior Member
 
Join Date: Apr 2007
Posts: 10
Default

I own a (Canon 70-200 2.8 IS).... Need some info on the Canon 1.4X and the 2X extenders.... Basically some pros and cons.... Do and don'ts.... etc....

Thanx in advance....


The Factor is offline   Reply With Quote
Sponsored Links
Old Apr 24, 2007, 3:50 AM   #2
Super Moderator
 
Mark1616's Avatar
 
Join Date: Oct 2005
Posts: 7,397
Default

As you are using Canon glass I would stick with canon TC's as they are going to give you the best results. If you were a Sigma user then I would use their TC's (actually I do, I have both their 1.4 and 2x TC's to go with my 70-200mm f2.8 and 120-300mm f2.8). I have use lesser 3rd party TC's in the past such as the Teleplus 2x TC and it is nowhere near as good as the Sigma and Canon will give you the best results.

OK, so what is going to happen when using the TC's?

With the 1.4x you will have a 98-280mm f4 (a 1.4x TC will lose 1 stop of brightness from the main lens).

With the 2x you will have a 140-400mm f5.6 ( a 2x TC will lose 2 stops of brightness).

There are other things that you should be aware of when using TC's, there will be a loss of quality but when the extra length is needed it is better than cropping down on the original and with the 1.4x I'm still very happy with 12"x8" prints the 2x is not as good but still usable where length is needed. One area that people do not always consider when using TC's and that is the distance you are trying to use the lens over. All lenses will have an optimum distance beyond which theAF is not as 'hot' as you are getting nearer to infinity. With a 200mm lens you are looking at about 20-30m for this so adding a TC might mean that the size of the subject you are shooting will mean you are now further away so focus is weaker. They are ideal for birds/wildlife and still work well in other situations but just wanted you to be aware of this. I was using my 120-300mm f2.8 with the 2x TC at the weekend shooting Cricket and this was the furthest distance I've shot over and found I really needed to stop down to get usable results.
Mark1616 is offline   Reply With Quote
Old Apr 24, 2007, 5:57 AM   #3
Senior Member
 
John at the Beach's Avatar
 
Join Date: Feb 2003
Location: Southeastern NC
Posts: 491
Default

I use a Tamron 1.4x converter with my canon 70-200 2.8L with good results...Never tried the canon 1.4x so I can't say one is better than the other...I do get a slight vignetting at 200mm, so beware of that...Thats not a problem for me because I like the effect...If I get a photo that I dont like the vignette in, I use PS and crop it out...:G
John at the Beach is offline   Reply With Quote
Old May 20, 2007, 10:27 PM   #4
Senior Member
 
Imacer's Avatar
 
Join Date: Jan 2004
Location: Juneau, Alaska
Posts: 474
Default

Do you lose your auto focus by using a extender?
Imacer is offline   Reply With Quote
Old May 21, 2007, 6:00 AM   #5
Senior Member
 
John at the Beach's Avatar
 
Join Date: Feb 2003
Location: Southeastern NC
Posts: 491
Default

No problems with auto focus from 70mm through 200mm...I just get the slight
vignette on the corners at the 200mm end, as I mentioned in my other post...
John at the Beach is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 10:52 AM.