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Your experience with the R5 af in low-light, high-ISO... advice, tips & tricks.

Started 3 months ago | Discussions thread
Ephemeris
Ephemeris Senior Member • Posts: 1,186
Re: Your experience with the R5 af in low-light, high-ISO... advice, tips & tricks.

R2D2 wrote:

John Sheehy wrote:

R2D2 wrote:

John Sheehy wrote:

thunder storm wrote:

R2D2 wrote:

Autofocus uses the processed image to work with.

I'm wondering why. I wouldn't expect it to.

Taken from a simple, "black box" view of the camera, it seems to be true that the camera is dependent upon the video fed to the EVF or LCD for AF. It may be possible that this isn't the true causality, and that it really has something to do with analog gains and exposure times used for live view, but you can take the association to the bank, functionally. The AF difference between Exposure Simulation and brightness normalization is not subtle; it is HUGE. It can be the difference between the AF system throwing up its hands almost immediately, and presenting a red AF failure box, or snapping quickly into confirmed focus.

I haven't played with Canon's picture style editor in a long time, so I don't know what the range of parameters is, but a picture style imported to the camera that almost completely flattens contrast and minimizes sharpness could help to determine if it is the video feed or the gains and exposure times that are the real cause.

I think the fact that enabling the 1.6x Crop Mode improves subject recognition tells us that it's likely the processed image "Feed" that's being used by the camera's AF (once DPAF has done its thing).

Yes, but unless we are using point AF, the area of the bounding AF box can make a difference, too, in how many pixels the AF needs to look through to find subjects, so that needs to be accounted for, unless flipping crop mode on still has the same bounding box, relative to the resulting frame.

Good thought, except it's not the speed or the efficiency of the subject detection that is affected. It is simply GO/NO GO. Recognize the subject or not.

I got my brain in a pickle whereby I thought that if the image pipeline is so important then popping a fancier screen on would make a difference.

Id love to see how the software works, some similink diagram or such but the nearest I get is object recognition, classification and fusion for vehicles.

There was a post recently about a system used at the world cup running some Nikon z9s. I noted they had lots of recognition of players and the ball, but also the ball and the kit had some transponders in them.

So in crop the dual pixel system doesn't change size. So does it use the same pixels irrespective of the crop facilities? Does the image pipeline have anything to do with the price of fish?

See some good resources and access to the software would keep me entertained over Christmas. Dear F. Xmas ...

My gut feeling is that you are correct, and I came to that likelihood soon after getting the R5. I just like to remain aware of other possibilities, which is part of the nature of science.

You are indeed very good at making US aware of different possibilities! Many thanks for upping the curve!

I have quite an unusual background I suppose but I very much enjoy learning new things, fixing things I already know but it's wrong or can be bettered, and supporting others in there life learning quests.

Maybe we will get some LiDARS on our next generation cameras to aid object tracking. One thing I have realised is that armed with an R5, an EF 70-200 II, a nice SD and CF card, battery grip with two charged lithium lumps, the bit that desperately needs upgrading or maybe trading in, is well, me 😂

Take care fella.

R2

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Good judgment comes from experience.
Experience comes from bad judgment.
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