Requesting opinions on your personal use of Canon Extender RF 1.4 and/or RF2.0 teleconverters

[garymak]

Hi, I'm requesting opinions from anyone who has direct personal use experience specifically with Canon Extender RF 1.4 and/or RF2.0 teleconverter with any of the permitted lenses but especially the RF100-500mm F4.5-7.1 L IS USM, with respect specifically to the following:

1) Any degradation in I.Q., e.g., sharpness, color, etc.

2) Any noticeable impact on lens function e.g., auto-focus, etc.

3) any other quirks or observations on using this RF extender

4) which one you use for what purpose, e.g., "2x for bird photography", "1.4 for travel photography", etc. and why you chose it.

I'm not looking for information on EF extenders (I've used EF ones for years) or extenders in general or thoughts in general, just if you have one of these two RF extenders specifically and what your personal experience has been with them.

Thanks in advance!

[shadowsports]

Hi Gary,

I have the RF 1.4x.  I purchased it and the RF 100-400 about the same time.  I purchased the RF 100-500 shortly thereafter.

For EF I owned a Sigma 150-600c with TC 1401 (1.4x).  I never used the TC. 😆.  Never felt like I needed to.  

For the RF 100-400 you can use either RF TC the full range of its FL.  For the RF 100-500 the lens has to be zoomed to 300 or more to connect the TC.  The TC works between 300-500mm.

You lose 1 stop of light with the 1.4x and 2 stops with the 2.0x.  (Like EF)  Again, I own the 1.4x.  On the RF 100-500 (300mm) which yields 420mm f5.6 becomes f8 and f7.1 becomes f10

AF is a little slower, and becomes more noticeable as light decreases. 

Worth noting.  DSLR's had a limitation where they could not AF when using a TC with an aperture above f8, or they would only work with 1 point AF.  R body's do not have this limitation.  They might be slow above f8, but they can technically focus. 😊   A tripod is a good idea.  Handheld is possible too.  After my next trip, I will likely get a RF 200-800 and shelf the 1.4x. 

Image degradation occurs because of magnification.  The 2.0x has its place too, but I have no experience with one.  Mostly because of the loss of light.  I purchased my RF 1.4x from Canon refurb.👍

[garymak]

Thanks, that's the kind of analysis I was looking for.  Much obliged. 

Followup question: how much IQ degradation? Something you notice upon close inspection or something that makes you wish you had a longer lens and didn't need a tele converter? You seem to imply the latter with your comment "After my next trip, I will likely get a RF 200-800 and shelf the 1.4x. "  (BTW, shouldn't you be saying "BEFORE my next trip, I will likely get a RF 200-800 and shelf the 1.4x. " 🤣😉)

Thanks.