08-19-2016 10:19 AM - edited 08-19-2016 10:29 AM
Check out this screenshot from a Lightroom plug-in that displays AF points. Check out the legend.
The points can appear in one of four different states.
[EDIT] Here's a sample AF point display from a different shot.
The center AF point had been manually selected, acquired a target, and maintained a locked focus state when shutter fired.
08-19-2016 11:07 PM
I followed the advice we usually give and reset the settings. 8^)
The focus point indication showed up in review.
So I started to add settings back. Long story short, it turned out to be the lens distortion correction, which I kind of expected. I guess smooshing the pixels for lens distortion correction keeps the focus points from showing up.
Which raises the question, how much sharpness do you lose with distortion correction on?
08-20-2016 07:34 AM
Lens Distortion Correction!?!? But, the focus point isn't part of the image at all. Hmmph. Maybe it has something to do with how the point is displayed in camera, because softare like DPP have no trouble displaying images with correction and AF points simultaneously.
08-20-2016 07:42 PM
08-20-2016 08:13 PM
08-20-2016 08:49 PM
Waddizzle - can you elaborate on this comment you made please, "Remember, it is not a display of whether or not, or where, the camera is focused. It is displaying the active AF point at the moment the shutter fired. It is not always necessary, or required, that an AF point be actively locked when the shutter fires.".
Doesn't the AF show what area it used to focus (assuming it had focused before the shutter was pressed)?
I always use the closest AF point (based on composition)... I use BBF and wait to see the af point light up (red) in the view finder and hear the beep then I press ever shutter. So upon review on the LCD I expect that where it shows the red box is where the af point used was and what was focused on (usually someone's eye). Is this logic/expectation not correct?
Well, I had thought I had explained it with the screen shot that I posted, which explained four states that AF points might be shown by that software package. The camera only displays one of those states [described here as "red + black"] during image playback.. The fact that you use BBF explains a lot, and I suspect I know the cure. Keep BBF pressed while you press the shutter.
When you use BBF, a rear button is programmed as "AF-ON", which activates the auto focus system. If the button is not being pressed, then the AF system is idle. If you press BBF, hear the beep, release the button, and press the shutter, then the AF point will be in the fourth state on the list, White + Red, becauses the AF system goes inactive when you release the BBF.
In other words, when the AF system goes inactive, then the AF point is no longer locked on a target. The lens remains in focus during this scenario, because nothing occurs to change it. With the AF system inactive, the camera certainly won't change the focus.
Try keeping the BBF button pressed after the focus confirmation beep, and while you press the shutter. The AF box should now show up during playback!
08-22-2016 12:29 PM
Thanks Waddizzle. I was viewing via my cell and for some reason those charts were not showing up/displaying. I am looking at it now on my PC and i can see them.
I do not have the LR plug in but will try to download.
I do have DPP but to be honest have never used other than when i first installed it years ago. When i first installed it I didn't really see the need/use for it since i was using LR and PS. In any case i just launched it and i have version 3.1.10 and it is not diplaying any images - instead all the images are grey boxes with an X through the grey box. All my images were shot on a Canon 6D in RAW so the only thing i can think of is that that version of DPP doesn't support that camera but seems odd... I found a link to verion 4.0 of DPP but it won't resolve so can't download ;(
So if i'm readying your last comment correctly you are suggesting that i keep the BBF pressed until after the shoot is taken (shutter pressed and released) - dont press the BBF hear the beep then lift from it - I can do that.
I am using Al Servo and i do understand now (thanks to you Waddizzle) that the red box would simply show the active AF point not necessarily where it focused. But I checked my camera again and AF Point Display (in the menu system) is Enabled (i haven't touched it/changed it in months and the image in question that i posted was taken last week). So i still don't understand WHEN in playback on the Camera on the LCD the red box would not show up?
08-22-2016 01:18 PM
Okay i just found the latest version of DPP off of Canon's site and installed. This is going to take some time to get used to using
In any case, when i look at the IN FOCUS image i showed at the beginning of the post (second closeup above that looks SHARP), in the DPP software THERE IS NO AF POINT "IN FOCUS" ( ie when i pick to have the software to "show all AF points in focus" there are NONE. If i pick for the software to show me "all AF points" then of course it does but NONE are read.
So that being the case, (this software doesn't show 'states' per say), what I think it is saying is that for that image NO AF point was in focus - that what likely happened is that i was using BBF but once i heard the beep i lifted my finger from BBF and then hit the shutter... so when the shutter was hit there was no AF point in focus. Thus the fact that that image is tack sharp is purely a coincidence!! ;( Am i correct???
Then in the first image (close up shown above that is NOT SHARP) where there is a AF Point showing in red (which i can see by selecting "show AF Points in Focus" in the DPP software) and the image is NOT Sharp then what the heck happened? Why is the second image, where the AF Point was active and in Focus not sharp??? i used the top right AF point on the 6D...
08-22-2016 02:12 PM
"So that being the case, (this software doesn't show 'states' per say), what I think it is saying is that for that image NO AF point was in focus - that what likely happened is that i was using BBF but once i heard the beep i lifted my finger from BBF and then hit the shutter... so when the shutter was hit there was no AF point in focus. Thus the fact that that image is tack sharp is purely a coincidence!!"
I wouldn't call it coincidence. The lens had focused, and the AF system was inactive. If the subject does not move significantly, and likewise for the camera, the subject should remain in focus. What is going to cause the subject to go out of focus?
Here's one way to look at it. I'll compare it to manually focusing the lens. When you press BBF, that is comparable to putting your hand on the focus ring. When you release BBF, that is comparable to your hand releasing the focus ring. What occurs when your hand is on the focusing ring depends upon the shooting mode, One Shot or AI Servo, you are using. Did you notice that I skipped over AI Focus mode, the one that is supposed to switch modes automatically? You should skip over it, too, if you do not already.
The AF point display in DPP is comparable to when your hand is actively touching the focus ring. It doesn't necessarily indicate where focus was locked. In One Shot mode, you could lock focus, and recompose the shot. The AF point that locked focus will be displayed, but since you recomposed the shot, then it will not be covering the area where it originally locked focus.
Similar scenarios can happen when you use AI Servo mode if you are photographing relatively still subjects. AI Servo adds the further complication in that it is looking for your shot go out-of-focus, OOF. It is anticipating movement, and looking for a target lock.
BTW, if you are not photographing moving subjects, then you should stick to One Shot mode. In my experience, I get consistently sharper photographs of relatively still subjects using One Shot mode, when compared to AI Servo. But, I can tap BBF when I am in AI Servo, which almost emulates using One Shot mode.
"... i used the top right AF point on the 6D..."
I always use the center AF point on the 6D. With many Canon lenses, the camera performs better, especially with the faster lenses. The center point is the AF point in the 6D with cross-type focuisng, which means it detect vertical and horizontal lines. The other AF points are either vertical or horizontal line sensitive. The center AF point can also perform high precision vertical-line sensitive AF when used with lenses that are f/2.8, or faster, and some f/4L lenses, too.
08-22-2016 03:55 PM
Thanks! that all makes sense.
when i said 'coincidence' what i meant was that i focused and between then and when i pushed shutter she was still on the same focal plain or within the dof thus all was good but had nothing to do with me actually activly focusing (ie per your example i had removed my hand from the focus ring if i had been manually focusing).
The lack of focus on the second image is concerning - yes it could be that since it is not the center one it is not as 'good' but i'll have to test to determine if i need to stick to the center one - hopefully not. I was using a 70-200 f/4 for that shot i think at about 100mm.
I have now installed the LR Plugin - it's interesting but i'm confused what the different states mean Do you mind helping me understand them?
This is what the Show Focus Point LR Plugin software states in the legend (in black text) and where i'm confused/looking for clarification as to meaning (in red) keeping in mind that i'm using BBF and I'm using Al Servo:
Red+White: Locked AF Point (focus achieved) point not orginally selected - i really don't understand this - i'm manually picking the AF points - ie i'm toggling between them and before i take a shot i'm clicking on the BBF button to confirm whihc one is active and swithing them around as necessary ... the definition on the legend suggest that i hadn't selected it thus how is that AF point being selected/used? .
Red+Black: Locked AF Point (focus achieved) point orginally selected - does this mean that i had picked this AF point AND that it had focused when i used the BBF button AND that it was still active and focused when i pushed the shutter button (becuase i still had my finger on the BBF button and the shutter)?
Black +White: Inactive AF Point - does this basically mean that no point was activated / selected or used since the last shot by the user/me? ie since taking my last shot i didn't select an AF point???
White+ Red: AF Point originally selected by user before taking image, but not locked in picture - does this mean that the user/I picked that AF point but then it wasn't active when the picture was taken (ie i had let go of the BBF button before hitting the shutter)?