Nikon Z7 493 autofokuspoints with auto distortion control active

felbo said:

Perhaps I'm stupid but how can firmware in camera know the right placement of the focus point on sensor vs viewfinder


Here are +5 distortion and -5 distortion images as layers in Photoshop

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Not sure to understand what this function is.

Every camera corrects distorsion now with the lens profile. Is there anything specific with Nikon ?

The camera has all the information to know the right placement then.

I was a bit unclear in what I mean. Well, with auto distortion on, and if you have a lens with distortion lets say +5, software in camera have to adjust with -5 so we get a view without distortion. So we really look at a distorted image in viewfinder which we place the focuspoint on. The firmware have to compensate for this to get the point "right". My wondering: Are focuspoint in the end absolute correct ? All time? If you have zoom lens with huge distortion, we will have an unlimited correction steps from wide angle to tele. The firmware have to adjust placement of all the 493 focus point in unlimited steps. It's a huge job for the algoritme. You get millions of adjustments in the whole zoom area. Nikon Z7 was only an example for this. Of course Nikon sure have done this perfect, but im thinking about this anyway. I get from time to time a bit misfocus with pin focus and Z7. Can be another thing. Sorry for my bad english, its not my first language

have a nice day

from felbo

felbo said:

I was a bit unclear in what I mean. Well, with auto distortion on, and if you have a lens with distortion lets say +5, software in camera have to adjust with -5 so we get a view without distortion. So we really look at a distorted image in viewfinder

Click to expand...

A corrected image you mean.

This requires lot's of computation

felbo said:

which we place the focuspoint on. The firmware have to compensate for this to get the point "right". My wondering: Are focuspoint in the end absolute correct ? All time? If you have zoom lens with huge distortion, we will have an unlimited correction steps from wide angle to tele. The firmware have to adjust placement of all the 493 focus point in unlimited steps

Click to expand...

I think the biggest computation was to calculate the corrected image. By doing so, it has calculated the corrected placement for the 493 focus points.

felbo said:

. It's a huge job for the algoritme. You get millions of adjustments in the whole zoom area. Nikon Z7 was only an example for this. Of course Nikon sure have done this perfect, but im thinking about this anyway. I get from time to time a bit misfocus with pin focus and Z7. Can be another thing. Sorry for my bad english, its not my first language

Click to expand...

Olympus has keystone compensation. It is crazy what cameras can do nowadays so I am not surprised.

Some cameras (go pro) use fisheye lenses and defish in live..

Maybe I missed something in what you meant. I admit I do not understand what auto distorsion does with Nikon because every camera corrects distorsion now (if it has the lens profile).

felbo said:

have a nice day

Click to expand...

Have a nice day too

felbo said:

from felbo

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chrisfisheye said:

felbo said:

I was a bit unclear in what I mean. Well, with auto distortion on, and if you have a lens with distortion lets say +5, software in camera have to adjust with -5 so we get a view without distortion. So we really look at a distorted image in viewfinder

Click to expand...

A corrected image you mean.

This requires lot's of computation

chrisfisheye said:

which we place the focuspoint on. The firmware have to compensate for this to get the point "right". My wondering: Are focuspoint in the end absolute correct ? All time? If you have zoom lens with huge distortion, we will have an unlimited correction steps from wide angle to tele. The firmware have to adjust placement of all the 493 focus point in unlimited steps

Click to expand...

I think the biggest computation was to calculate the corrected image. By doing so, it has calculated the corrected placement for the 493 focus points.

chrisfisheye said:

. It's a huge job for the algoritme. You get millions of adjustments in the whole zoom area. Nikon Z7 was only an example for this. Of course Nikon sure have done this perfect, but im thinking about this anyway. I get from time to time a bit misfocus with pin focus and Z7. Can be another thing. Sorry for my bad english, its not my first language

Click to expand...

Olympus has keystone compensation. It is crazy what cameras can do nowadays so I am not surprised.

Some cameras (go pro) use fisheye lenses and defish in live..

Maybe I missed something in what you meant. I admit I do not understand what auto distorsion does with Nikon

Click to expand...

Nikon Z cameras with pro optics tex 24-70 2.8S or 70-200 2.8S, have option to put auto distortion off in the menu. It's not funny because it's a lot of distortion there in viewfinder. So, with auto distortion off, put an af point in the corner area on a small thing with pin point (smallest point). You are on tripod and care about movement. If you then turn on auto distortion without moving anything, you can see the focus point have moved a bit from recent placement and its not over the little thing anymore. If you then move the point over the little thing again, how can you be sure there is an af pixel on the little thing now?

chrisfisheye said:

because every camera corrects distorsion now (if it has the lens profile).

Click to expand...

yes, and Adobe Lightroom refuse to turn it off...

chrisfisheye said:

chrisfisheye said:

have a nice day

Click to expand...

Have a nice day too

chrisfisheye said:

from felbo

Click to expand...

Click to expand...

felbo said:

chrisfisheye said:

felbo said:

I was a bit unclear in what I mean. Well, with auto distortion on, and if you have a lens with distortion lets say +5, software in camera have to adjust with -5 so we get a view without distortion. So we really look at a distorted image in viewfinder

Click to expand...

A corrected image you mean.

This requires lot's of computation

felbo said:

which we place the focuspoint on. The firmware have to compensate for this to get the point "right". My wondering: Are focuspoint in the end absolute correct ? All time? If you have zoom lens with huge distortion, we will have an unlimited correction steps from wide angle to tele. The firmware have to adjust placement of all the 493 focus point in unlimited steps

Click to expand...

I think the biggest computation was to calculate the corrected image. By doing so, it has calculated the corrected placement for the 493 focus points.

felbo said:

. It's a huge job for the algoritme. You get millions of adjustments in the whole zoom area. Nikon Z7 was only an example for this. Of course Nikon sure have done this perfect, but im thinking about this anyway. I get from time to time a bit misfocus with pin focus and Z7. Can be another thing. Sorry for my bad english, its not my first language

Click to expand...

Olympus has keystone compensation. It is crazy what cameras can do nowadays so I am not surprised.

Some cameras (go pro) use fisheye lenses and defish in live..

Maybe I missed something in what you meant. I admit I do not understand what auto distorsion does with Nikon

Click to expand...

Nikon Z cameras with pro optics tex 24-70 2.8S or 70-200 2.8S, have option to put auto distortion off in the menu. It's not funny because it's a lot of distortion there in viewfinder. So, with auto distortion off, put an af point in the corner area on a small thing with pin point (smallest point). You are on tripod and care about movement. If you then turn on auto distortion without moving anything, you can see the focus point have moved a bit from recent placement and its not over the little thing anymore. If you then move the point over the little thing again, how can you be sure there is an af pixel on the little thing now?

Click to expand...

Ok I get your point now. You are right.

I think it is close enough anyway, it might select the closest AF point, not necessarily the one selected.

I don't know to be honest but I would not worry about it because there are plenty of AF points.

felbo said:

felbo said:

because every camera corrects distorsion now (if it has the lens profile).

Click to expand...

yes, and Adobe Lightroom refuse to turn it off...

felbo said:

felbo said:

have a nice day

Click to expand...

Have a nice day too

felbo said:

from felbo

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