Brave New World

[Alastair Norcross]

I remember when I got my 7DII in 2014. One of the selling points was that the center focus point could AF with lenses with a maximum aperture of F8, instead of the usual limit, which applied for the other 64 points, of F5.6. This meant that you could use an F4 lens with a 2X extender, so long as you used the center point only, or an F5.6 lens with a 1.4X extender. Well, here we are just nine years later, and I can use most of the frame on my R6II or R7 with an F11 lens, and still about half the frame with my R6II with an F16 lens. Here's a shot I took yesterday with the RF 800 F11 with 1.4X extender. That's 1120mm F16, handheld at 1/500 (I could have gone slower, but birds move, even while perched). The AF had no problem at all. That's pretty amazing. And even with an 1120mm lens, this bird was so small in the frame that I had to crop it to fewer than 2000 pixels in each dimension (that's more than a 2X crop), and then use Topaz to upsize it:







--
“When I die, I want to go peacefully in my sleep like my grandfather. Not screaming in terror, like the passengers in his car.” Jack Handey
Alastair

anorcross

Keen hobbyist since teaching myself film photography as a teenager in the 70s, using manual SLRs and black and white film. Love photographing people and animals.

anorcross.smugmug.com

Equipment in profile

 

[Ephemeris]

I remember when I got my 7DII in 2014. One of the selling points was that the center focus point could AF with lenses with a maximum aperture of F8, instead of the usual limit, which applied for the other 64 points, of F5.6. This meant that you could use an F4 lens with a 2X extender, so long as you used the center point only, or an F5.6 lens with a 1.4X extender. Well, here we are just nine years later, and I can use most of the frame on my R6II or R7 with an F11 lens, and still about half the frame with my R6II with an F16 lens. Here's a shot I took yesterday with the RF 800 F11 with 1.4X extender. That's 1120mm F16, handheld at 1/500 (I could have gone slower, but birds move, even while perched). The AF had no problem at all. That's pretty amazing. And even with an 1120mm lens, this bird was so small in the frame that I had to crop it to fewer than 2000 pixels in each dimension (that's more than a 2X crop), and then use Topaz to upsize it:



--
“When I die, I want to go peacefully in my sleep like my grandfather. Not screaming in terror, like the passengers in his car.” Jack Handey
Alastair
http://anorcross.smugmug.com
Equipment in profile

Nice shot Alistair. I think your personal optical tracking should be congratulated I wouldn't have spotted it.

Just to ask a question on your comment below. Why half the frame at F16?

Well, here we are just nine years later, and I can use most of the frame on my R6II or R7 with an F11 lens, and still about half the frame with my R6II with an F16 lens

 

[Alastair Norcross]

I remember when I got my 7DII in 2014. One of the selling points was that the center focus point could AF with lenses with a maximum aperture of F8, instead of the usual limit, which applied for the other 64 points, of F5.6. This meant that you could use an F4 lens with a 2X extender, so long as you used the center point only, or an F5.6 lens with a 1.4X extender. Well, here we are just nine years later, and I can use most of the frame on my R6II or R7 with an F11 lens, and still about half the frame with my R6II with an F16 lens. Here's a shot I took yesterday with the RF 800 F11 with 1.4X extender. That's 1120mm F16, handheld at 1/500 (I could have gone slower, but birds move, even while perched). The AF had no problem at all. That's pretty amazing. And even with an 1120mm lens, this bird was so small in the frame that I had to crop it to fewer than 2000 pixels in each dimension (that's more than a 2X crop), and then use Topaz to upsize it:

Nice shot Alistair. I think your personal optical tracking should be congratulated I wouldn't have spotted it.

Just to ask a question on your comment below. Why half the frame at F16?

Well, here we are just nine years later, and I can use most of the frame on my R6II or R7 with an F11 lens, and still about half the frame with my R6II with an F16 lens

That's just what happens when you put the 1.4X extender on the 800 F11 on the R6II. The focus box shrinks. I think it's still a bit bigger than it is for the bare lens on the R5 and R6, but it's smaller than the focus box for the 800 alone on the R7. It must have something to do with how much light is hitting the sensor.

--
“When I die, I want to go peacefully in my sleep like my grandfather. Not screaming in terror, like the passengers in his car.” Jack Handey
Alastair

anorcross

Keen hobbyist since teaching myself film photography as a teenager in the 70s, using manual SLRs and black and white film. Love photographing people and animals.

anorcross.smugmug.com

Equipment in profile

 

[Ephemeris]

I remember when I got my 7DII in 2014. One of the selling points was that the center focus point could AF with lenses with a maximum aperture of F8, instead of the usual limit, which applied for the other 64 points, of F5.6. This meant that you could use an F4 lens with a 2X extender, so long as you used the center point only, or an F5.6 lens with a 1.4X extender. Well, here we are just nine years later, and I can use most of the frame on my R6II or R7 with an F11 lens, and still about half the frame with my R6II with an F16 lens. Here's a shot I took yesterday with the RF 800 F11 with 1.4X extender. That's 1120mm F16, handheld at 1/500 (I could have gone slower, but birds move, even while perched). The AF had no problem at all. That's pretty amazing. And even with an 1120mm lens, this bird was so small in the frame that I had to crop it to fewer than 2000 pixels in each dimension (that's more than a 2X crop), and then use Topaz to upsize it:

Nice shot Alistair. I think your personal optical tracking should be congratulated I wouldn't have spotted it.

Just to ask a question on your comment below. Why half the frame at F16?

Well, here we are just nine years later, and I can use most of the frame on my R6II or R7 with an F11 lens, and still about half the frame with my R6II with an F16 lens

That's just what happens when you put the 1.4X extender on the 800 F11 on the R6II. The focus box shrinks. I think it's still a bit bigger than it is for the bare lens on the R5 and R6, but it's smaller than the focus box for the 800 alone on the R7. It must have something to do with how much light is hitting the sensor.

--
“When I die, I want to go peacefully in my sleep like my grandfather. Not screaming in terror, like the passengers in his car.” Jack Handey
Alastair
http://anorcross.smugmug.com
Equipment in profile

Ah okay. Thanks.

Perhaps that's the reason but if we shut an aperture down it doesnt affect it.

I recall the r5 has something like 1600 focus areas, but I don't know what an area is made up of.

I feel like I knew the answer once upon a time but don't really understand how the dual pixels are perhaps converted into areas, and then what occurs.

https://www.dpreview.com/forums/thread/4505420