boblug wrote:
I'm not so sure now Steve.
If you read the words literally from the following excerpts from focus modes:
Dynamic - The focus point is selected manually. The camera focuses on the subject in the selected focus point when autofocus is initiated, but if the subject later leaves the selected point for brief periods, the camera will focus based on information from surrounding points (the edges of the area surrounding the selected focus point are shown by small dots, but all 9, 25, 72, or 153 focus points in the area are used for focus)
Then 3D tracking - The initial focus point is selected manually. While the shutter-release button is pressed halfway, the camera uses color information to track subjects that leave the selected focus point and selects new focus points as required.
The difference is the use of the word track. It does not mention that in the dynamic mode just saying a surrounding point will be used but not related to the original which intimates complete refocus.
Annoying I agree, but my personal expectation is that dynamic is a safety net for moving off selected focus point and keeping original target. ...Show more →
My understanding is similar to what you are getting at. Basically in Dynamic the other points around the chosen point are their to "assist" the chosen point if it loses good contrast under its point. Canon uses this "assist" term for its AF Expansion modes. However, Canon only has a 4 or 8 points surrounding the chosen one so it is a still a very small area being used. More like D9 on the D5.
What Dynamic is not intended to do (I think) is remember the subject under the selected point and track it with the other points. This is what 3D mode does. So if the system loses contrast under the main point it will switch to another point to maintain focus. The problem is that if you move that main point off your intended subject and it falls on another contrasty subject (that could be in the background) the system will refocus with the main point. I'm pretty sure this is how it works....setting the delay to 5 will give you more time to get back onto the intended subject. If you are tracking a bird against sky then the Dynamic mode should work, but tracking a bird against tree background will not work if you don't do your job perfectly. With a tree/contrasty background one should either set delay to 5 or use Group AF (or maybe 3D) instead.
Still if this is the way it is working I don't really see any use for D153 and little use for D72. I wish my D500 had D9 as that is what I would use all the time along with Group. Just like on my Canon bodies I use Expansion 8 pt (D9) and Small Zone (Group).
boblug wrote:
I'm not so sure now Steve.
If you read the words literally from the following excerpts from focus modes:
Dynamic - The focus point is selected manually. The camera focuses on the subject in the selected focus point when autofocus is initiated, but if the subject later leaves the selected point for brief periods, the camera will focus based on information from surrounding points (the edges of the area surrounding the selected focus point are shown by small dots, but all 9, 25, 72, or 153 focus points in the area are used for focus)
Then 3D tracking - The initial focus point is selected manually. While the shutter-release button is pressed halfway, the camera uses color information to track subjects that leave the selected focus point and selects new focus points as required.
The difference is the use of the word track. It does not mention that in the dynamic mode just saying a surrounding point will be used but not related to the original which intimates complete refocus.
Annoying I agree, but my personal expectation is that dynamic is a safety net for moving off selected focus point and keeping original target. ...Show more →
The descriptions for dynamic af and 3d af are worded "exactly" the same in both the d800 and d500 manuals. 3d af behaves similarly in both cameras, yet dynamic af behaves drastically different in the two cameras. So either dynamic af is broken, or Nikon decided to radically change how it works without letting us know.
Steve Perry wrote:
The reason I thought it was broken was because it didn't appear to be handing off the AF point as the old system did. Anytime I looked at the AF point that was used in View NX-i (or on the camera) it would show only the primary point, never anything else. With the D810, it would show that it selected and used a different point (as seen in the photos at the beginning of this thread). So, it looked like it was never handing off the AF point and it made me think there may be something wrong.
However, thanks to Snapsy, we've had a breakthrough and have been able to look deeper into the EXIF and found that the camera is actually switching AF points. Nikon seems like it's just showing the selected AF point, much the way it does with Group (i.e. with Group, it only shows you where the Group was, not which specific AF points it used, however, if you dig into the EXIF far enough, you can see the specific AF point used at capture)....Show more →
I really hope when Nikon look at this correspondence they realize this not showing which AF point was actually used is a separate issue that they should fix.
The descriptions for dynamic af and 3d af are worded "exactly" the same in both the d800 and d500 manuals. 3d af behaves similarly in both cameras, yet dynamic af behaves drastically different in the two cameras. So either dynamic af is broken, or Nikon decided to radically change how it works without letting us know.
The part about Nikon making a change and not letting us know, I am pretty sure, is fairly normal.
The descriptions for dynamic af and 3d af are worded "exactly" the same in both the d800 and d500 manuals. 3d af behaves similarly in both cameras, yet dynamic af behaves drastically different in the two cameras. So either dynamic af is broken, or Nikon decided to radically change how it works without letting us know.
The part about Nikon making a change and not letting us know, I am pretty sure, is fairly normal.
A change for the worse IMHO, lots of AF points in Dynamic not doing anything, my D810 & D4s in Dynamic AF ROCKED!
Why Nikon would you want to go backwards on something as sacred as AF, hopefully having a bad dream, wake me up when its fixed.
I'm copying and pasting this from another site where I had posted it:
I've been working w/ the D5 autofocus system for a while now, trying to figure out what mode's best to use and when... it seems the D5 is a little different than any previous Nikon I've owned.
First off, if using any dynamic mode other than auto or 3D the camera does not report which AF point it thinks was in focus... It only shows the selected AF point as being in focus (even if it clearly was not). I know it is tracking, but I have no idea how well it is tracking other than in-focus images...which seem to be less than expected/with other modes.
Secondly, the "focus tracking with lock-on" settings seems to be more "selected point priority" settings... If set to a low level it seems the focus does not track very well at all, even if there is no apparent reason for AF to have been lost. The only way I can get 1/2 decent tracking for difficult subjects like BIF is to set "blocked shot" to maximum delay with "subject motion" set to erratic. Even then it won't stick with a focus area for very long, even if it is held stationary. My personal results seem to be better using 3D or Auto.
The "logic" seems to be:
The blocked shot setting is actually "selected point priority" determining how quickly the AF reverts to the selected point. And even at maximum delay, it's not very long.
The subject motion setting is a "probability logic"... If set to "steady" the camera will revert to the selected point more quickly than if set to "erratic." There's less "reason" for AF to be lost so it reacts a bit quicker, but it doesn't seem to make a big difference.
And none of this is affected by whether the focus area (subject) is lost or not.
Basically, I'm finding that the dynamic focus modes (d9-d153) are *worse* than previous Nikons when the subject is particularly difficult to track... it just will not stick long enough. And it means I have to be much more careful about what AF mode I select as none of the dynamic modes are particularly flexible across a wide array of subjects/situations.
(It also means you can't really use them for the focus/recompose technique, not that it's an issue really)
All of this is quite different IME.
Of course, as things get easier the dynamic modes work much better... but then there is less need for them. On the other hand, "Auto" is surprisingly good in a wide variety of settings (I still haven't used 3D enough to have a solid opinion of it yet).
The part about Nikon making a change and not letting us know, I am pretty sure, is fairly normal.
A change for the worse IMHO, lots of AF points in Dynamic not doing anything, my D810 & D4s in Dynamic AF ROCKED!
Why Nikon would you want to go backwards on something as sacred as AF, hopefully having a bad dream, wake me up when its fixed.
The D5 is most definitely tracking in D9-D153... this is easily tested with a small high contrast subject in front of a low contrast (OOF) background.
sk66 wrote:
I'm copying and pasting this from another site where I had posted it:
I've been working w/ the D5 autofocus system for a while now, trying to figure out what mode's best to use and when... it seems the D5 is a little different than any previous Nikon I've owned.
First off, if using any dynamic mode other than auto or 3D the camera does not report which AF point it thinks was in focus... It only shows the selected AF point as being in focus (even if it clearly was not). I know it is tracking, but I have no idea how well it is tracking other than in-focus images...which seem to be less than expected/with other modes.
Secondly, the "focus tracking with lock-on" settings seems to be more "selected point priority" settings... If set to a low level it seems the focus does not track very well at all, even if there is no apparent reason for AF to have been lost. The only way I can get 1/2 decent tracking for difficult subjects like BIF is to set "blocked shot" to maximum delay with "subject motion" set to erratic. Even then it won't stick with a focus area for very long, even if it is held stationary. My personal results seem to be better using 3D or Auto.
The "logic" seems to be:
The blocked shot setting is actually "selected point priority" determining how quickly the AF reverts to the selected point. And even at maximum delay, it's not very long.
The subject motion setting is a "probability logic"... If set to "steady" the camera will revert to the selected point more quickly than if set to "erratic." There's less "reason" for AF to be lost so it reacts a bit quicker, but it doesn't seem to make a big difference.
And none of this is affected by whether the focus area (subject) is lost or not.
Basically, I'm finding that the dynamic focus modes (d9-d153) are *worse* than previous Nikons when the subject is particularly difficult to track... it just will not stick long enough. And it means I have to be much more careful about what AF mode I select as none of the dynamic modes are particularly flexible across a wide array of subjects/situations.
(It also means you can't really use them for the focus/recompose technique, not that it's an issue really)
All of this is quite different IME.
Of course, as things get easier the dynamic modes work much better... but then there is less need for them. On the other hand, "Auto" is surprisingly good in a wide variety of settings (I still haven't used 3D enough to have a solid opinion of it yet)....Show more →
If you'd like to see what AF point the D5/D500 actually used for dynamic you can use exiftool with the following command, which will report the AF points for all files in the specified directory and all subdirectories beneath it as well:
exiftool.exe -PrimaryAFPoint -AFPointsUsed -r -ext nef "f:\picsSteve Perry D5-D500 dynamic AF issue" > output.txt
Result in output.txt:
======== f:/pics/Steve Perry D5-D500 dynamic AF issue/set_2/DSC_5454.NEF
Primary AF Point : E9 (Center)
AF Points Used : E9
======== f:/pics/Steve Perry D5-D500 dynamic AF issue/set_2/DSC_5455.NEF
Primary AF Point : E9 (Center)
AF Points Used : E9
======== f:/pics/Steve Perry D5-D500 dynamic AF issue/set_2/DSC_5456.NEF
Primary AF Point : E9 (Center)
AF Points Used : E9
======== f:/pics/Steve Perry D5-D500 dynamic AF issue/set_2/DSC_5457.NEF
Primary AF Point : G9
AF Points Used : G9
======== f:/pics/Steve Perry D5-D500 dynamic AF issue/set_2/DSC_5458.NEF
Primary AF Point : E9 (Center)
AF Points Used : (none)
2 directories scanned
12 image files read
======== f:/pics/Steve Perry D5-D500 dynamic AF issue/set_2/DSC_5454.NEF
Primary AF Point : E9 (Center)
AF Points Used : E9
======== f:/pics/Steve Perry D5-D500 dynamic AF issue/set_2/DSC_5455.NEF
Primary AF Point : E9 (Center)
AF Points Used : E9
======== f:/pics/Steve Perry D5-D500 dynamic AF issue/set_2/DSC_5456.NEF
Primary AF Point : E9 (Center)
AF Points Used : E9
======== f:/pics/Steve Perry D5-D500 dynamic AF issue/set_2/DSC_5457.NEF
Primary AF Point : G9
AF Points Used : G9
======== f:/pics/Steve Perry D5-D500 dynamic AF issue/set_2/DSC_5458.NEF
Primary AF Point : E9 (Center)
AF Points Used : (none)
2 directories scanned
12 image files read
I don't see any difference in the point selected vs point used, except the last image where (possibly) focus was not achieved.
sk66 wrote:
I'm copying and pasting this from another site where I had posted it:
I've been working w/ the D5 autofocus system for a while now, trying to figure out what mode's best to use and when... it seems the D5 is a little different than any previous Nikon I've owned.
First off, if using any dynamic mode other than auto or 3D the camera does not report which AF point it thinks was in focus... It only shows the selected AF point as being in focus (even if it clearly was not). I know it is tracking, but I have no idea how well it is tracking other than in-focus images...which seem to be less than expected/with other modes.
I use the ShowFocusPoints plugin in Lightroom and it shows the focus point selected in dynamic AF mode, not necessarily the selected focus point. So that part is working and I can also confirm that tracking is working in Dynamic AF mode when there is a clean background. The real question is if tracking really loses focus on the subject when presented with a contrasty background even if the subject is within the focus area.
Steve's experiment with his daughter running towards him seems to confirm that it does lose focus.
Steve: based on your investigations to date, do you have a reasonable answer to why that happened?
sk66 wrote:
I don't see any difference in the point selected vs point used, except the last image where (possibly) focus was not achieved.
Sorry, I should have also remarked that the "Primary AF Point" and "AF Point Used" will both reflect the dynamic AF point that the camera selected, unlike what the titles would suggest of "Primary AF Point" being the user-selected initial point and "AF Points Used" being what the camera selected. This EXIF encoding is the same as previous Nikon bodies btw.
Warkari wrote:
I use the ShowFocusPoints plugin in Lightroom and it shows the focus point selected in dynamic AF mode, not necessarily the selected focus point.
- Amit
For the D5? It doesn't work for me... even Nikon's NXD doesn't show the active point.
snapsy wrote:
Sorry, I should have also remarked that the "Primary AF Point" and "AF Point Used" will both reflect the dynamic AF point that the camera selected, unlike what the titles would suggest of "Primary AF Point" being the user-selected initial point and "AF Points Used" being what the camera selected. This EXIF encoding is the same as previous Nikon bodies btw.
boblug wrote:
I'm not so sure now Steve.
If you read the words literally from the following excerpts from focus modes:
Dynamic - The focus point is selected manually. The camera focuses on the subject in the selected focus point when autofocus is initiated, but if the subject later leaves the selected point for brief periods, the camera will focus based on information from surrounding points (the edges of the area surrounding the selected focus point are shown by small dots, but all 9, 25, 72, or 153 focus points in the area are used for focus)
Then 3D tracking - The initial focus point is selected manually. While the shutter-release button is pressed halfway, the camera uses color information to track subjects that leave the selected focus point and selects new focus points as required.
The difference is the use of the word track. It does not mention that in the dynamic mode just saying a surrounding point will be used but not related to the original which intimates complete refocus.
Annoying I agree, but my personal expectation is that dynamic is a safety net for moving off selected focus point and keeping original target. ...Show more →
First, I gotta laugh - "Single point with a safety net" is exactly how I describe Dynamic in my upcoming book! Great minds and all!
The odd thing is, the description is the same for the old system and they now work differently. However, I think I finally have it figured out and will be posting after I proof read it again. (need to look away for a minute )
arbitrage wrote:
My understanding is similar to what you are getting at. Basically in Dynamic the other points around the chosen point are their to "assist" the chosen point if it loses good contrast under its point. Canon uses this "assist" term for its AF Expansion modes. However, Canon only has a 4 or 8 points surrounding the chosen one so it is a still a very small area being used. More like D9 on the D5.
What Dynamic is not intended to do (I think) is remember the subject under the selected point and track it with the other points. This is what 3D mode does. So if the system loses contrast under the main point it will switch to another point to maintain focus. The problem is that if you move that main point off your intended subject and it falls on another contrasty subject (that could be in the background) the system will refocus with the main point. I'm pretty sure this is how it works....setting the delay to 5 will give you more time to get back onto the intended subject. If you are tracking a bird against sky then the Dynamic mode should work, but tracking a bird against tree background will not work if you don't do your job perfectly. With a tree/contrasty background one should either set delay to 5 or use Group AF (or maybe 3D) instead.
Still if this is the way it is working I don't really see any use for D153 and little use for D72. I wish my D500 had D9 as that is what I would use all the time along with Group. Just like on my Canon bodies I use Expansion 8 pt (D9) and Small Zone (Group)....Show more →
The problem was, in the past the system would track and stick with the subject. However, your description is accurate for how it works now. The fact that it changed is what's causing the issue. And I agree - the way it works now, D153 and D72 are not as useful as D21 / 51 IMO.
The descriptions for dynamic af and 3d af are worded "exactly" the same in both the d800 and d500 manuals. 3d af behaves similarly in both cameras, yet dynamic af behaves drastically different in the two cameras. So either dynamic af is broken, or Nikon decided to radically change how it works without letting us know.
The part about Nikon making a change and not letting us know, I am pretty sure, is fairly normal.
Warkari wrote:
I use the ShowFocusPoints plugin in Lightroom and it shows the focus point selected in dynamic AF mode, not necessarily the selected focus point. So that part is working and I can also confirm that tracking is working in Dynamic AF mode when there is a clean background. The real question is if tracking really loses focus on the subject when presented with a contrasty background even if the subject is within the focus area.
Steve's experiment with his daughter running towards him seems to confirm that it does lose focus.
Steve: based on your investigations to date, do you have a reasonable answer to why that happened?
)