Canon 1.4X II T/C

[clutchkiller]

Just a couple of comparison pictures, one with the T/C, and one without. Both images were shot from the exact same distance, and have had the same size single crop applied to them. The birds are different species, but relatively have the same body size.

Picture using only the Canon 300mm f/4 (minus T/C)

Picture using the Canon 300mm f/4 combined with the T/C

I've read that using the T/C slows down the lens, I haven't been using either the lens or converter long enough to notice a difference.

 

[Lan-Lord]

Paul, thanks for the test, and keep them coming. I like the look (and reach!) of the 300 + 1.4.

Using the TC does slow down the lens by 1-stop of light. (eg, the lens will not gather as much light when compared to not using the TC). It looks like in your test that you may have been in auto mode, but even so, when you look at the exif data on those 2 images, you can see that the photo with the TC has less light (noted by the ISO, f/Stop, and shutter values) . Fortunately, in the situation that you were shooting (mid-day, and adequate sunlight), you could afford to loose 1-stop of light with the TC, but if you were shooting in a low-light situation, the performance would have been "slower" with the TC.

But those 2 shots look great from your setup. Plus seeing that you have an effective focal length of 420mm (not counting crop factor) is a good thing too!

 

[clutchkiller]

Okay got ya Chris. I should have looked at the camera settings (Aperture Value).

Here are two more for a comparison. Both of these have the same shutter and ISO speeds. Both pictures have been left completely unedited for the comparison, only converted from RAW to JPEG and batch re-sized to post here. Both taken again from the same distance.

Without T/C. Aperture 4.5

With T/C. Aperture 5.6

edit- Shutter speed was @ 1/320 and ISO was @ 1600. I've been taking pics of some birds, the weather is horrible right now.