Canon 100-400 with converter ?

Has anyone here had experience using the canon 100-400 L lens and 40D body with either the Canon 1.4 or 2x converter?. I realize you would loose auto focus, but is the IQ degraded to the point of not being usable? I'd like to be able to fill the frame more with some of the smaller birds, but a longer lens is just not in the picture in the near future($$$). I have done some testing with the tamron 1.4 and 2X, and the IQ does drop off a bit. I was curious as to whether anyone has had success with the Canon units.

Hi Dave,
I tried a lot of shots with my 1-400L and Canon TCs with both the 20D and the 40D. I personally liked the challenge although I got a lot more failures than successes. As for being usable, that depends on your intended use and personal standards of IQ. Here's a 100% crop of an unprocessed image with the 20D and the 1-400L and the Canon 1.4xTCII.

This is what I cleaned it up to for a quick web post. I also printed out an 8 x 10 pic that came out pretty good (at least to me).

And here's another 100% crop of an unprocessed image. This one was with the 40D and the Canon 2xTC (Used tripod, MLU, and cable release. f14, 1/6s, ISO 800)

Thank you Steve for taking time to post the images. The processed imnage looks pretty good. I'm just trying to find a way to get around cropping my images so heavily. Even with a noise filter I just don't get that nice crisp image that I see so much of here. I'll keep experimenting. I know the real answer is to finfd a way to move in closer.

My experience with a 1DMK2 and 100-400 with 1.4 TC is variable. If I stop down to f 10 or 11 and use good long lens technique I can get usable shots with decent sharpness. However, wide open it is not up to par. Remember my 1DMK2 will AF with the 1.4 TC. I have tried the taping trick with my wife's 40 D and I find the AF is too slow and too erratic.

Here are 3 images taken this morning all with 100/400 with Tamron 1.4TC and Canon 40D. All images taken wide open. The spoonbill was taken through a chicken wire fence. The spoonbill and the hawk are captive.

Spoonbill as mentioned above.

3rd image. ISO 1600

Thanks Michael. Those are pretty impressive shots. There is a touch of noise in the shots, but again I guess it's all about what the final use will be.

I've only ever tried the Canon 1.4X extender on a 100-400mm lens on a 20D and a 5D body.
It's possible to get a reasonibly good result given the right conditions but I'd say this is the exception rather than the rule and would only use that combination as a very last resort.
I havn't tried a 2X on the 100-400mm but would expect the image quality to be poor.

You may get away with using the 1.4X on the 100-400mm for static subjects but for small and active birds it's a very poor combination IMHO.

I have used the 1.4x with the 100-400 on a 10D, 20D and 1D Mark III. My experience pretty much agrees with others. I found the resulting images to be quite soft. I can get an acceptably sharp image but it is rare. Also, the loss of light at 400mm was often a problem. I just found I could not hook up the TC and shoot with confidence. I have now had the ability to use the 1.4X with a 500mm, f/4.0, IS, and I can already tell the problem with the 100-400/1.4 combo was not the TC; it was most definitely the lens. When using the TC and the 500 combo, my images don't look any different than shots taken with the 500 alone.

Paul

Thanks Justin and Paul. I can only dream of the day when I could own the 500. I think I would have to agree that the big problem is that most birds don't seem to know the word stationary, therin lies my problem. I had even contmplated the Sigma 50-500 ((heard some people had good results) but isn't that a 6.something on the long end. Won't that also cancel autofocus on the 40D?

The lens 50/500 and the 170/500 are ƒ6.3 at the long end, but tell the camera they are ƒ5.6, so autofocus works. My wife has the Sigma 170/500 and it is amazingly sharp at 500 mm definitely as good or better than the 100/400L is at 400 mm. Now if the auto focus on that was was as fast as the 100/400L I would be using one!!!