FloridaDrafter
- التعليق
This review is based on use with a Canon EOS 5D mark IV and the Canon EF 100-400mm f/4.5-5.6 L IS USM II lens. The Canon EF 1.4X III Telephoto Extender gives this lens a max of 560mm f/8, so you loose one full stop. To put that in perspective, from f/5.6 to f/8 (one full stop), you are only getting 1/2 of the light that you were getting at f/5.6. For me, there was a slight learning curve and it took some fiddling with settings to get good exposure in lower lighting. The day I got this, it was one of those overcast days where the sun just looks like a smudge in the sky, but I just couldnt wait for better conditions, and really, why should I? It was a pretty good test actually. Five of the shots Ive attached were taken that day; the Downy Woodpecker, two of the Eastern Bluebirds, the Dove, and the Tufted Titmouse. My settings ranged from 1/200th shutter / ISO 1200 to 1/1000th shutter / ISO 800, and the darker images were at f/8. Most were taken under 60 feet away with the flying birds being over 150 feet. All shots have been cropped to various degrees. There is a wee bit of IQ loss, but nothing that you will notice on prints from 11x17"ish below and for general use, like Facebook, forums, and other places you might want to post images, even high quality ones. Once you convert to JPeG or other "lossy" formats, its a moot point anyway. I am a "pixel peeper" so I did notice some IQ loss when zoomed past 100%, but honestly, how many people do that?. I dont see any color fringing or vignetting , even though that has been reported, however, I seem to concentrate on the subject, which I know will be cropped, so if it is indeed there, its of no concern to me. I tested it, using the mentioned 100-400mm lens, on the 5D mark IV, the 7D mark II, and the Rebel T7i. All focus points worked on each of these cameras, even in outside lighting that wasnt optimal. I was really surprised because reviewers have stated that you loose some peripheral focus points. Focus did slow down in low light on all the cameras I tested on, but honestly, it wasnt that bad. Good lighting was a different story, all cameras AF was snappy as usual. Now, when Canon says the Canon EF 1.4X III Telephoto Extender will only work with certain lenses, it has nothing to do with optics or light, it just plain wont fit other lenses. For the heck of it, I tried to attach it to an EF 70-300mm f/4-5.6 L IS USM II, an EF 70-300mm f/4-5.6 IS USM II (non L), and an EF 100mm f/2.8 (I know, I just wanted to see), and it just would not fit the lens. The front element of the Canon EF 1.4X III Telephoto Extender went too far into the lens to allow it to attach. This device will not replace a dedicated long lens, but it will sure improve your reach with very little loss in IQ. You just have to pick your lighting battles.