Comparison of RF 1200mm f/8 L and EF 600mm f/4 L II with 2X III

Comparison of RF 1200mm f/8 L and EF 600mm f/4 L II with 2X III (RF 1200mm was tested recently):

https://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=1599&Camera=1508&Sample=0&FLI=0&API=0&LensComp=748&CameraComp=979&SampleComp=0&FLIComp=2&APIComp=0

I think, EF II version is providing a better image. By the way, the RF 600mm f/4 L with 2X does not do as well as EF 600mm f/4 L with 2x III.

What surprises me is that although canon has optimized the $20K RF 1200mm lens (with the extender slapped to the back of it), in terms of sharpness it does not appear to do as well as the old EF 600mm II version with 2X III extender.

I have never tried my 600mm with my 2X III, having seen this, I am now very motivated to test it.

Also may be of interest:

https://www.the-digital-picture.com/Reviews/Canon-RF-1200mm-F8-L-IS-USM-Lens.aspx

amm wrote:

Comparison of RF 1200mm f/8 L and EF 600mm f/4 L II with 2X III (RF 1200mm was tested recently):

https://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=1599&Camera=1508&Sample=0&FLI=0&API=0&LensComp=748&CameraComp=979&SampleComp=0&FLIComp=2&APIComp=0

I think, EF II version is providing a better image. By the way, the RF 600mm f/4 L with 2X does not do as well as EF 600mm f/4 L with 2x III.

What surprises me is that although canon has optimized the $20K RF 1200mm lens (with the extender slapped to the back of it), in terms of sharpness it does not appear to do as well as the old EF 600mm II version with 2X III extender.

I have never tried my 600mm with my 2X III, having seen this, I am now very motivated to test it.

Also may be of interest:

https://www.the-digital-picture.com/Reviews/Canon-RF-1200mm-F8-L-IS-USM-Lens.aspx

CA is horrendous on 600 f4 II + TC2 III. and that goes for the sharpness and contrast.

I purchased both 1.4X and 2X extenders as having both extenders were mandatory. However, I only used 2X with 70-200mm f2.8 couple of times till its novelty wore off. I never used it again with any other lenses. Perhaps because of seeing all the unsatisfactory test results I found on the internet with 2X extenders. Having seen Canon's 20K, RF 1200mm test results couple of days ago, motivated me to try 2xIII with EF 600mm II.

I was not feeling that good today (got my booster shot which is giving me chills and a bad headache), but I decided to try the EF 600mm f4 II with the 2X III on R7, before the weather get worse.

So here are couple of pictures. Both pictures are taken with the aperture wide open (forgot to try other settings). The focusing speed was OK, not very fast but I did not limit the range, I should have. R7 focusing would get confused every now and then when background was busy, but I have observed the same issue with the bare lens as well.

Among couple of hundred pictures that I took (some under high contrast situations), I did not notice any CA, even before using DPP4 which corrects it.

R7, EF 600mm with 2X III, f/8, 1/1250 Sec, ISO 1600

R7, EF 600mm with 2X III, f/8, 1/750 Sec, ISO 2500

these 2 images look real good for that combination.

An even lower budget path to long focal length.

Since I was stuck at home, I experimented with stacked teleconverters. Hand held, auto focus, F number of 18 when wide open would be 16, motion blur, diffraction blur, very slow AF, DPP digital lens optimizer, focus limiter switch set to full range. With this combination if there is low contrast then AF will bang back and forth between near and far.

Monarch Butterfly (Danaus plexippus) on Zinnia in Norman, Oklahoma, United States on October 5, 2022. Focal Length 1120.0 mm, EF100-400mm f/4.5-5.6L IS II USM +1.4x III + Kenko TELEPLUS HD C-AF 2X DGX

Thanks, I have been telling the same thing to my wife and that I should spend half of the saving, she is not buying it

Make: Canon
Model: EOS R7
Date Taken: 2022-10-09 16:10:28
Exposure Time: 1/83 sec
F Number: f/9.11
ISO Speed Ratings: ISO 640
Focal Length: 1200 mm

Distance to subject is about 35 meters.

KevinRA wrote:

JohnMoyer wrote:

An even lower budget path to long focal length.

Since I was stuck at home, I experimented with stacked teleconverters. Hand held, auto focus, F number of 18 when wide open would be 16, motion blur, diffraction blur, very slow AF, DPP digital lens optimizer, focus limiter switch set to full range. With this combination if there is low contrast then AF will bang back and forth between near and far.

Monarch Butterfly (Danaus plexippus) on Zinnia in Norman, Oklahoma, United States on October 5, 2022. Focal Length 1120.0 mm, EF100-400mm f/4.5-5.6L IS II USM +1.4x III + Kenko TELEPLUS HD C-AF 2X DGX

A lovely butterfly.

I do wonder here though if you are gaining anything by stacking the TC's with this combo - e.g. the re the depth of field and sharpness hit.

Thanks.

In this case you are correct that I did not gain anything except isolation of the subject from nearby surroundings. There is much less contrast with the stacked teleconverters and increasing depth of field increases diffraction blur. There is motion blur because the bug was moving and the wind was moving the flower.

It was an experiment. It demonstrates that at some time in the future when I cannot get close enough this will work. Usually 560mm or 800mm is enough. And it costs less money than some other solutions to the same problem.

JohnMoyer wrote:

KevinRA wrote:

JohnMoyer wrote:

An even lower budget path to long focal length.

Since I was stuck at home, I experimented with stacked teleconverters. Hand held, auto focus, F number of 18 when wide open would be 16, motion blur, diffraction blur, very slow AF, DPP digital lens optimizer, focus limiter switch set to full range. With this combination if there is low contrast then AF will bang back and forth between near and far.

Monarch Butterfly (Danaus plexippus) on Zinnia in Norman, Oklahoma, United States on October 5, 2022. Focal Length 1120.0 mm, EF100-400mm f/4.5-5.6L IS II USM +1.4x III + Kenko TELEPLUS HD C-AF 2X DGX

A lovely butterfly.

I do wonder here though if you are gaining anything by stacking the TC's with this combo - e.g. the re the depth of field and sharpness hit.

Thanks.

In this case you are correct that I did not gain anything except isolation of the subject from nearby surroundings. There is much less contrast with the stacked teleconverters and increasing depth of field increases diffraction blur. There is motion blur because the bug was moving and the wind was moving the flower.

It was an experiment. It demonstrates that at some time in the future when I cannot get close enough this will work. Usually 560mm or 800mm is enough. And it costs less money than some other solutions to the same problem.

for me, using my canon 100400 mk2 and a TC 1.4 III has been enough to deal with images like this and birding. i do have the canon 600 f4 mk2 but it is a monster to handhold without a tripod.

the other and better option for me is using my canon 300 f2.8 II and TC 2.0 III, which gives me an instant 600 f5.6 with high IQ focal length. 300 mk2 is a pretty light lens for me that doesn't tire me out carrying it all day. YMMV.