Extenders Which RF extender unit should I get?

[JCBigler]

I want to get one of the RF extender units to use with my RF100-500 lens.

Will mainly be used for solar and lunar photography. I doubt I would use it for much else. But with my R6 mkII, which do you think would be best?

The 1.4x would give 700mm plus the 1.6 crop would effectively be up to 1,120mm. Or the 2x would give 1,000mm plus the 1.6 crop would give 1,600mm.

But losing the 1 vs 2 stops of light, for solar eclipses I don’t think it would matter. For lunar photography, would the 2x be too much zoom and too little light?

 

[David Stallard]

Just remember with the extender you start your range at 300mm (the 100-500 wont allow any shorter) I would guess for astro / solar work you are using a solid tripod? stabiliser off and either will do you well, I have both and with the mirrorless system wouldn't hesitate to use either - you will be surprised what else you will use it for once you start ;-)

 

[Nick L]

I have both and I use the 1.4x much more, its lighter and smaller but it is a restricted range with both as David said.

This was shot hand held at 1000mm with the 2x on a very clear night last february

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[JCBigler]

I have both and I use the 1.4x much more, its lighter and smaller but it is a restricted range with both as David said.

This was shot hand held at 1000mm with the 2x on a very clear night last februaryView attachment 34063

That's a super nice shot.

Do you feel like you are limited with the reduced light gathering of either of them for things like lunar photography?

Usually the moon is so bright that you kind of have to stop down some or use a really fast shutter speed anyway.

 

[Nick L]

For normal 1/2 moon to full moon no issue, for a lunar eclipse I wou;d ;ike to use the 2x but I know there is so little light I would tru with and without I think ( I have never used the R5 on a lunar eclipse - later this year I hope we do not have a cloudy night as there is one)

 

[jcass]

I want to get one of the RF extender units to use with my RF100-500 lens.

Will mainly be used for solar and lunar photography. I doubt I would use it for much else. But with my R6 mkII, which do you think would be best?

The 1.4x would give 700mm plus the 1.6 crop would effectively be up to 1,120mm. Or the 2x would give 1,000mm plus the 1.6 crop would give 1,600mm.

But losing the 1 vs 2 stops of light, for solar eclipses I don’t think it would matter. For lunar photography, would the 2x be too much zoom and too little light?

Are you using a solid tripod and ball/gimbal head? I'm assuming so.

The 2x with the 100-500 L give you 1000mm at ~f/14. But that is wide open. Stopping it down a little and you're looking at 1000mm at around f/16 or f/18. I think the extra reach is more important than the aperture in your use-case. But be very careful, you're shooting a moving object and you may need to bump the ISO to keep your shutter speed high enough.

 

[Only RF]

It's going to be pretty jiggly with a 2X at 1600mm even with a tripod. I had both EF ones in my DSLR days but used the 1.4 most often. This is with the R7, 100-500 and 1.4. I was out for a walk in the dusk doing some low light tests and spotted this. That was from the summer of 2023 and that haze is from the wildfires in Canada.

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It cleaned up and cropped well.

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[Only RF]

I also have the R6II and it surprised me when I tried this crop. I did not expect that. You will be able to get the details out with some careful PP. The 1.4 as others said will be more versatile. From personal experience these days I'd only use a 2X on prime lens but that is just me.

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[miuzi]

I use the 2x, albeit with the 100-400mm f/5.6-8 and an EOS R8, and have found it really invaluable for some of the things I like to shoot, like the moon or airshows. I bought it specifically with the April 2024 total solar eclipse in mind, and it was worth it just for that. My light situation is even worse than your hypothetical pairing, dropping to f/16 wide open at 800mm, with no IBIS as one would find in the R6 mkii, but I find it works great for me to get the moon.

 

[Only RF]

I use the 2x, albeit with the 100-400mm f/5.6-8 and an EOS R8, and have found it really invaluable for some of the things I like to shoot, like the moon or airshows. I bought it specifically with the April 2024 total solar eclipse in mind, and it was worth it just for that. My light situation is even worse than your hypothetical pairing, dropping to f/16 wide open at 800mm, with no IBIS as one would find in the R6 mkii, but I find it works great for me to get the moon.

I did use a 2x on my EF 100-400 II and R. It worked pretty good.