BetterPhoto Q&A
Category: New Questions

Photography Question 
Robyn Gwilt
BetterPhoto Member Since: 7/15/2005
 

Converters


Hi there - anyone know if you can use a Canon 2x converter with a Sigma lens? - i.e. a 18-200 or a 28-300?


To love this question, log in above
5/26/2006 10:03:01 AM

 
Jon Close
BetterPhoto Member Since: 5/18/2000
  Canon EF 2x and EF 1.4x may work with a couple of Sigma lenses - like the 70-200 f/2.8 EX - but definitely will NOT fit on their 18-200 or 28-300. Wide-angle zooms and f/xx-6.3 lenses are usually pretty bad candidates for use with teleconverters anyway.


To love this comment, log in above
5/26/2006 10:28:08 AM

 
Robyn Gwilt
BetterPhoto Member Since: 7/15/2005
  Thanks Jon. And the new Sigma 17-70 F2.8-4.5. Could I damage either the converter or the lens by trying, or will I just get a messed up shot?


To love this comment, log in above
5/26/2006 1:52:21 PM

 
anonymous A.    I have a Sigma 28-300 on my Canon D20. I regularly use a 2x converter with it, and though it is a 3rd party brand I can't see any reason Canon's own tcv wouldn't work equally well.


To love this comment, log in above
5/27/2006 7:03:31 AM

 
Robyn Gwilt
BetterPhoto Member Since: 7/15/2005
  David, I take it then I will not damage either the converter or the lens? I'm going on a 5 day coastal hike, carrying EVERYTHING on my back - food, clothes etc, sleeping in huts - therefore, trying to keep my photography equipment weight down. I'll have a waist belt for the camera, with 2 cylindrical pouches either side - I thought I'd put spare batteries & converter in one, and the 28-300 lens in the other - as I can also put the polarizer on it. To take my Canon IS 70-200 F2.8 is going to be just too much weight and bulk, so this was an alternative. My concern is damaging anything?


To love this comment, log in above
5/27/2006 8:42:20 AM

 
Slim Brady 
BetterPhoto Member Since: 3/1/2006
  just buy a real nice P&S and enjoy yourself. Don't take your heavy artillery with you, thats for shooting weddings. Shoot raw, take an epson 2000( for example )and lots of batteries and have fun


To love this comment, log in above
5/27/2006 10:20:49 AM

 
anonymous A.    A few lenses and converters that worked with film SLSs won't fit the digital equivalent cameras because the mounts are physically shorter; but if it attaches without force, everything will be fine.
Don't worry about poor Box Brownie Brady B. ... or maybe we SHOULD worry if he has lost the joy of the hike!


To love this comment, log in above
5/27/2006 3:56:22 PM

 
Slim Brady 
BetterPhoto Member Since: 3/1/2006
  sorry Mr Richie Rich, just tryn to save our girl a bigger hike than she bargained for


To love this comment, log in above
5/27/2006 9:11:13 PM

 
anonymous A.    No worries, Barry... and no offence intended, either. Be well and prosper. RR


To love this comment, log in above
5/28/2006 3:41:33 AM

 
Robyn Gwilt
BetterPhoto Member Since: 7/15/2005
  Ok, just got the converter :) :) But.... it doesn't fit the Sigma lenses - you were right Jon. I'll pack the backpack, see what the weight is, and then make a decision - but OMG the Canon Lens/Converter adds HUGE weight. Might just take the others. In the meantime, if ANY of you are thinking of visiting South Africa - this is a part of the coast thats a must-see. Best option is to book out the whole trail - takes 12 people, but we're limiting it to 8, and splitting the cost of R6000.00 ( USD923) check out http://www.footprint.co.za/otter.htm and thanks for all the advice.


To love this comment, log in above
5/28/2006 12:30:46 PM

 
Slim Brady 
BetterPhoto Member Since: 3/1/2006
  I did a 14mile hike and it was not with other photographers. 20pounds, tripod food and another heavy(water). The trails weren't perfectly marked, so we had a guide (people have gotten lost for a couple of days before). Problem was that I wanted to stop and take pictures along the way and by the time I got my shot the others were so far ahead I had to run (I fell alot). I actually landed backwards on my photobag once and hear a load crack. Luckily it was the lens hood. So it was very fustrating to say the least. Then on the way back it started to rain (which wasn't in the forecast). So I had to stop and pack the plastic hood over the bag and even miss the shots that I planned on the way back.


To love this comment, log in above
5/28/2006 2:50:24 PM

 
Jon Close
BetterPhoto Member Since: 5/18/2000
  Sorry I've been away and didn't get back with a follow up on this thread. To David and others, the Canon teleconverters are designed with an extended front element that nests into the back of only a select few compatible lenses. That front element will collide with the rear element of other lenses, causing physical damage to both. Sigma's EX teleconverters are similar. Kenko and Tamron teleconverters are designed so that they will mount to most lenses without problem.

Note that Canon's EF-S lenses extend their rear element backwards into the camera body. There currently are no teleconverters compatible with the EF-S lenses. But that's ok, since EF-S is generally limited to wide angle zooms that don't give good results with TCs anyway.

TCs are best used with prime lenses and zooms with maximum aperture of f/2.8 or f/4. Because the TC lengthens the focal length, but cannot make the lens wider to gather more light, the maximum aperture is reduced by 1 stop with a 1.4x, and 2 stops with a 2x. For example, a 70-300 f/4-5.6 zoom with a 2x TC becomes a 140-600 f/8-11 lens. Most autofocus SLRs require a maximum aperture of f/5.6 or larger to work, so you lose AF operation with the TC, and the smaller aperture also means the viewfinder is much darker making manual focus difficult.


To love this comment, log in above
5/29/2006 5:40:51 AM

 
Robyn Gwilt
BetterPhoto Member Since: 7/15/2005
  Thanks Jon - I'm just going to stick to using it on my Canon - doesn't fit anywhere else as I've discovered :)


To love this comment, log in above
5/29/2006 11:32:13 AM

 
Log in to respond or ask your own question.