Tell me about the RF 1.4 & 2x extenders

birdbrain wrote:

Texchappy wrote:

What are your thoughts on the extenders? Would you get the 1.4 or the 2? I would have thought the 1.4X but saw a video saying the 2X is the one to get.

I have found no problems using the RF 2x on the RF 100-500!

It produces very good results, samples posted earlier by me.

I have not noticed any slowdown in AF as mentioned in other posts.

I have nothing but praise for the RF 2x it is so far in advance of the EF 2x III which I never really liked.

It's interesting that in this thread previous threads about extenders with the R5 and the RF 100-500 there are numerous opinions expressed by those who "know" based not on experience with the combination but by "what everyone knows or should know about extenders."

Phil, gimp_dad and Texchappy have had good experiences with the RF2X and the 100-500. I throw my hat into the same ring as those RF2X owners and users: my experience has been quite good.

I ordered the 2X extender when I ordered my 100-500 for several reasons:

1) For my use the 1.4 extender was insufficient. The 100-500 stretched to 700mm at the long end was not enough more reach than a little cropping of the bare lens image.

2) I thought about the 300mm limitation on the base lens when mounting the extender on the 100-500. My assumption from the start was that there were engineering goals set by Canon regarding the R5 and the RF 100-500 that were a great fit for my wishes.

So, a major selling point for me of the R5 and the 100-500 lens (and the combination was essential in my decision) is the low weight, small size, better balance (than the heavier, front-heavy) Sigma 150-600C I used for years with my Canon 7DMk II. I saw that the lens was made lighter and without that front-heavy awkwardness by limiting the maximum aperture to 7.1 at full zoom. That brought out the nay-sayers. They didn't actually compare that aperture properly with the EF 100-400, i.e. with both lenses at 400mm--where the RF100-500 is only 1/3 stop slower than the EF 100-400.

Instead of putting larger and heavier glass in the 100-500 to make it faster at full zoom, they made it really sharp when wide open at full zoom instead--so no stopping down was necessary (or useful) to improve sharpness.

I guessed (without knowing) that if the engineers could have made that tidy, light weight lens super sharp over the full zoom range without elements that interfered with mounting a sharp 2X extender below 300mm zoom then they would have. If they could have without compromising their overall goals. I like their choice.

I reasoned (without knowing) that they chose to make the fit work only beyond 300mm because making it fit over the full zoom range would have required them to have compromised one or more of their design goals. Goals like extraordinary sharpness for a 100-500 zoom lens especially when wide open at full zoom and their goal of low weight and small size in the package. Maybe I was wrong about the thinking but I do think that they thought about it before accepting what I find tolerable--the 300mm limitation.

3) The argument about atmospherics ignores the obvious reality: if your subject is at a distance that you cannot reduce and still capture it, then you are stuck with the same atmospherics regardless of how what hardware you use. No lens overcomes atmospherics--only getting closer does that.

The identical atmospherics are there for cropping the image of the bare lens. It's there for shooting with either an inexpensive but slow 600 or 800 prime or a hugely costly fast and sharp 600 or 800 prime. Shoot at a distance may be required for the shot and the atmospherics are there no matter what lens you have. You have it and you learn to live with it and use the best tool for the job in spite of those atmospherics. For me it is the handy and easily carried RF2X.

For me, a couple of hundred meters from the Pacific Ocean and a few miles from the 45th parallel, heat waves are not an atmospheric problem. Wind is. We cope.

Phil has shown that the 100-500 plus RF2X produces great photos at modest distances. As I said, my use demands something for greater distances. The bare lens is great for BIF but I wanted something that would be good for shooting chicks on a cliff ledge 60m distant. I can always use my 7DmkII with the Sigma 150-600 on a tripod with its effective 960mm equivalent reach, but I also wanted to hand hold my R5 and get the reach.

So, I've had no regrets purchasing the RF2X. Optimizing my use of it is still a work in progress but we don't have chicks in the eyrie yet.

1000mm about 72m away (google earth is my friend).

1000mm and about 64m distance

800mm and a bit closer than above.

Not shown are photos taken at other focal lengths. The combination is quite sharp at all focal lengths. You can look at the full size images to find downy feathers here and there that demonstrates the resolution/sharpness as much as anything.

Don