Extender???

[Catmendo]

I would like to hear from some of you more experienced guys on Canon's Extender's. My main question is this. Will my 100-400mm retain its ability to remain sharp when using an extender???

[MARINERMAGNUM]

Sharpness will fall off about 10-20% in my experience with the 1.4 on the 100-400. You will also lose auto focus as well as some contrast and it adds some CA.

[Dbl]

What will happen with the 100-400 is its ability to focus. On any non 1 series camera you will lose auto focus capability above an aperture of f5.6. So when you add the 1.4 or 2x converter your aperture will exceed that.

There is a procedure to tape pins on the converter to stop the lens from reporting aperture so you can retain auto focus. This is hap-hazard at best. I was able to get it to work on occasion when I owned that lens but the auto focus speed slowed down way to much to be useful.

Kenko converters have been said to work with this combo but the loss of IQ and focus speed make this a last resort attempt at longer reach in my opinion.

[MN Shutterbug]

but the auto focus speed slowed down way to much to be useful.

The Af speed has to be faster than someone like me attempting to manual focus. I have the Kenko 1.4 and have used it just once, to try it out. I should just sell it. I always forget I even have it in my bag. I grew up with manual focus cameras and lenses. Unfortunately, I got older. It takes me much more time and is a lot tougher to get a sharp photo, if I can't rely on AF. Here is one of a few shots I took with the Kenko on my 100-400. I think it's sharp enough, but the coloring in the stomach, seems a bit weird. This bugger was quite aways from me.

[Steve Foss]

Stu, autofocusing aside, in very good light with a subject close to you that requires little or no cropping, the IQ is still good. Add either less than optimal light or a distant subject and it falls off too much.

I used the Kenko 1.4 and the Canon 1.4 on the 100-400 and, like X-T, eventually forgot they were in the bag and relied on woodscraft to get closer to the subject.

[MARINERMAGNUM]

I'm thinkin of gettin one of these with my Cabela's credit card bucks. Anybody here got one?

[MN Shutterbug]

I'm thinkin of gettin one of these with my Cabela's credit card bucks. Anybody here got one?

I've been tempted. I'd like to see one in person, so to speak, to find out if you can see anything coming from the side of you.

[Catmendo]

Great commentary gents and good sound advice! In the future, as I continue to evolve along in the world of photography, I will now begin to plan a strategy for a budget that will be geared towards the purchase of a lens with more reach. Like most of you, I would love to go out and purchase something in the neighbourhood of a 600mm. So with that said, that's what I will set my sights on.

[Steve Foss]

Stu, you might think in terms of the 500 instead. It's 8 pounds instead of the 12 pounds of the 600, with nearly as much reach, and it resolves more sharply than your 100-400. Even strong guys have trouble handholding the 600, so it's pretty much always a monopod or tripod deal, and that can get cumbersome. I can handhold the 500 for up to a minute or two at a time with no trouble. I can't say the same for the times I've shot the 600.

Just some more food for thought.

Also, any of the Canon telephoto prime lenses can take the 1.4 TC without the loss of image quality you get on the 100-400/TC.