p.3 #1 · Canon EOS R7 Mark II to Have Stacked 40MP Sensor?
AmbientMike wrote:
That's interesting he seems to be doing quite well using it, i doubt it's competitive vs your 500 though at 100% im a direct comparison. Are you saying f/11 on the lens, or f/11 effective, 1/3 stop down or 1 1/3? They always used to say one stop down for 1.4 to get best performance after basically adding 7 elements to your lens, not too surprising imo
I have a hard time seeing advice using tc's on zooms, they used to say not to do that. Currently a thread about 70-200/2.8 having 2x recommendations though, I'd probably be pretty hesitant to do that ...Show more →
You really should test equipment yourself to see how it performs and if that is acceptable.
Stopping down a full stop may have made sense 20 years ago when primes and TCs were less advanced, but today about 1/3 is enough sometimes or sometimes you don't at all. The 100-500 is not the right lens to use regularly with a TC. It's just that Canon is weak on good zoom options over 500mm. Ether you use the 1.4x TC and suffer the IQ, you use the 200-800 which is generally worse lens and slow, or you use one of the shorter zooms with a TC like the 100-300/2.8.
That 70-200/2.8 Z is something special just looking at the MTF and tests. I hope it's a sign of the future.
EBH
Dec 29, 2025 at 01:24 AM
AmbientMike Offline • • • • • • [X]
p.3 #2 · Canon EOS R7 Mark II to Have Stacked 40MP Sensor?
EB-1 wrote:
You really should test equipment yourself to see how it performs and if that is acceptable.
Stopping down a full stop may have made sense 20 years ago when primes and TCs were less advanced, but today about 1/3 is enough sometimes or sometimes you don't at all. The 100-500 is not the right lens to use regularly with a TC. It's just that Canon is weak on good zoom options over 500mm. Ether you use the 1.4x TC and suffer the IQ, you use the 200-800 which is generally worse lens and slow, or you use one of the shorter zooms with a TC like the 100-300/2.8.
That 70-200/2.8 Z is something special just looking at the MTF and tests. I hope it's a sign of the future.
Interesting, you recommend I test it myself, then end your post going by an MTF test.
The 180 needed one stop down for best iq, even though it's sharpest in the center at almost max aperture. Although you could get good results at <5.0 on the lens, or <7.1 effective. Most lenses aren't best at max aperture and adding a tc doesn't seem to help, of course increasing the FL is a huge tc advantage.
