Are any of you using the 2x or 1.4x extender? What are your thoughts on this? I have the 70-200 f2.8 IS and am looking for an economical way to extend my range. If you have one, which do you have / prefer and how often do you use it? <BR><a href="http://www.amazon.com/Canon-EF-Extender-Telephoto-Accessory/dp/B00009XVBY/ref=sr_1_1?ie=UTF8&amp;s=electronics&amp;qid=12321 69683&amp;sr=8-1" target="_blank">http://www.amazon.com/Canon-EF-Extender-Telephoto-Accessory/dp/B00009XVBY/ref=sr_1_1?ie=UTF8&amp;s=electronics&amp;qid=12321 69683&amp;sr=8-1</a>

you lose a couple (if not more) stops on your lens using an extender.

The 2X was designed to work best with the super tele primes and it's amazing on them. It's also very good on the 70-200's but as Joe mentioned it automatically loses 2 stops so your 70-200 becomes an f5.6 lens. This is not the end of the world if you're using it outdoors and you have IS. The 2X on my 70-200 f4 L IS well even though it's f8 still AF's on my 1 series. <BR> <BR>The first jet ski is a shot with the Canon 2X on my 70-200, the second is the 400 f5.6L with Canon 1.4X and the bird is done with the 2X on my 400DO which is what I bought the 2X to use with. <BR> <BR><img src="http://www.wakeworld.com/MB/Discus/messages/87667/660302.jpg" alt="Upload"> <BR> <BR><img src="http://www.wakeworld.com/MB/Discus/messages/87667/660301.jpg" alt="Upload"> <BR> <BR> <BR> <BR> <BR><img src="http://www.wakeworld.com/MB/Discus/messages/87667/660303.jpg" alt="Upload"> <BR> <BR>(Message edited by richd on January 17, 2009)

Rich ~ Thanks for the info! I knew I would loose 2 stops, my biggest concern was the few reviews I read where people mentioned they lost sharpness with the extender. For the price I think I will pick one up and give it a try.

I love using the the following website for comparing lenses! <BR> <BR>I set it up to compare the 70-200mm without and with the 2x extender (for the 400mm it sets it to f5.6 right away.) If you set it to 280 mm (1.4 extender equiv) the f-stop is f4.5. <BR> <BR>Mouse over the image to compare the sharpness and details between the two lenses: <BR> <BR><a href="http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=103&amp;Camera=9&amp;Sample=0&amp; FLI=4&amp;API=0&amp;LensComp=103&amp;CameraComp=9& amp;SampleComp=0&amp;FLIComp=6&amp;APIComp=0" target="_blank">http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=103&amp;Camera=9&amp;Sample=0&amp; FLI=4&amp;API=0&amp;LensComp=103&amp;CameraComp=9& amp;SampleComp=0&amp;FLIComp=6&amp;APIComp=0</a> <BR> <BR> <BR>However you can't beat a "real world" example like Rich's!!! Rich owns all the lenses so you can just ask him to post up examples! LOL... ok maybe not ALL, just the good ones! ;-) <BR> <BR>(Message edited by dcervenka on January 17, 2009)

I'm not sure that's a good example David. The exposure looks way off.

The ISO chart or rich's photo?

The chart looks like it has some exposure discrepancies between the two examples.

ISO is about: <a href="http://www.the-digital-picture.com/Help/ISO-12233.aspx" target="_blank">http://www.the-digital-picture.com/Help/ISO-12233.aspx</a> <BR> <BR>Word!

I can see the CA increases on that chart but I think it's a bit deceptive as far as sharpness due to the density differences in the black.

My original comparison was to show the difference between the 70-200 with and without the 1.4 and 2x extender. <BR> <BR>Compare it to another lens like the 300 f2.8 <BR> <BR><a href="http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=103&amp;Camera=9&amp;Sample=0&amp; FLI=4&amp;API=0&amp;LensComp=249&amp;CameraComp=9& amp;SampleComp=0&amp;FLIComp=0&amp;APIComp=0" target="_blank">http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=103&amp;Camera=9&amp;Sample=0&amp; FLI=4&amp;API=0&amp;LensComp=249&amp;CameraComp=9& amp;SampleComp=0&amp;FLIComp=0&amp;APIComp=0</a> <BR> <BR>and I think you can clearly see the difference in sharpness.

Wow. Stop splitting hairs about it. Those comparison tests are done in a lab setting, so who knows how much difference there will be in the real world. I'm sure a shaky hand or slow AF would ruin more photos than the negligible loss in sharpness caused by a 2.0x TC. <BR> <BR>FWIW- the world didn't end when I put a Canon 1.4x TC on my 70-200. I would post a sample photo but I'm half afraid that pulling that particular external from my closet might set off 'the big one.' We just got done hearing about all those quakes in Yellowstone and I don't feel like tempting fate. Sorry.

I just looked at the link Dave posted with the comparison and I would say that is about right. Remember those are unprocessed 100% pixel based crops off a test chart. <BR> <BR>My shots are processed, sharpened and reduced for the web which will hide much of the 2X's shortcomings. <BR> <BR>Walt: good call- the TC's due tend to increase CA and reduce contrast in general which is what those test examples are showing. The 2X is much worse then the 1.4X in that regard.