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TonyR
18th December 2016, 08:38 PM
I posted this at dpreview but I'll post it here too as Olympus mught see it.


So, I've had my E-M1 MkII for a couple of days now and I am very much enjoying using C-AF with the new subject tracking algorithm in All-points with AF Area Pointer set to On2 to give the dynamic "dancing" display of focus points. It seems to work very well at isolating the nearest subject.
However, I am somewhat confused about the other AF area selection opportunities.


First of all, since there are now 121 focus points, they are smaller than those on the MkI. Perhaps this is why the small single box has been dropped as the ordinary single box is already quite small.


Now the five-area and 9-area AF point selections seem to work a bit like the All-area selection. However, the dynamic "dancing" display of focus points is not available. Only the initial focus point acquired is highlighted in green and it does not change. It does appear that the other focus points in the group are used as, if you move the group off the subject, the green confirmation box goes out. It reappears if the group is moved back over the subject even if the highlighted point is still actually off the subject. So, what does this mean?


The next issue is that the 9-area group is actually quite small. It is going to be harder to keep it on a bird in flight than the MkI was. SImilarly what is that 5-area group for? It is the same height and width as the 9-area so is it really going to bahve any differently? And we have nothing between 9-area and All-areas.


As an ex software designer this offends me. It is almost like the All-areas system was developed by one team and the others by a second team.
So Olympus, why didn't you give us the option of choosing from a list of focus group sizes as follows: 11 x 11 (All-areas), 9 x 9, 7 x 7, 5 x 5, 3 x 3 (9-area) and 1 x 1 (single point). Allow us to move the group around where the group is smaller than All-areas and give us the dynamic "dancing" display of focus points and new subject tracking algorithm in all cases. Not only would this mean that a single AF routine could be used for all AF point selections but it would also mean that the smaller groups would have progressively higher performance as the number of points needing to be considered would be reduced. If the number of selections is thought to be too long, you could give us a list to select from a bit like that for drive modes (which has all the diamond options disabled by default to keep the list short).


What's not to like? Why didn't you give us this Mr. Olympus? How about doing it this way in firmware 2.0?

Gwyver
19th December 2016, 01:07 PM
Tony,
Leaving aside your point about more choices of multi point focus groups, the other part reads like a request for the behaviour you might expect C-AF+Tr should provide.

Just out of interest have you tried C-AF+Tracking with a 5 or 9 point focus group on a BIF and if so does it work (well)?

TonyR
19th December 2016, 01:46 PM
Tony,
Leaving aside your point about more choices of multi point focus groups, the other part reads like a request for the behaviour you might expect C-AF+Tr should provide.

Just out of interest have you tried C-AF+Tracking with a 5 or 9 point focus group on a BIF and if so does it work (well)?

I haven't tried C-AF+Tr a great deal but from what I have tried it isn't great. It works to an extent with a bird against a blank sky but can quickly lose the subject when a busy background appears behind it. It doesn't ssem to hold any advantages over C-AF.

I get the impression that many don't realise that Olympus have implemented an entirely new and very effective subject tracking system when C-AF with All points is selected. From what I can tell, this works mainly on focus distance to track the subject and so will continue to focus on the bird even when it moves from a clear sky to in front of a busy background. It is a proper, grown-up C-AF system just like a good dslr. It's just a shame that it only works with All points which was the motivation for my post. If it could be restricted to smaller groups of points it would be more effective at picking up the intended target at the start while still making it relatively easy to keep the subject within the group as tracking progresses. I suspect that 9-area might work the same way but just not showing the dynamic display of focus points. However, 9-area is quite hard to keep on the target as the group is quite small now.

andym
19th December 2016, 03:02 PM
Anyone played about with the "tight and loose" settings for tracking yet?

Waiting for some better weather before I venture into the world of CAF.

TonyR
19th December 2016, 03:07 PM
Anyone played about with the "tight and loose" settings for tracking yet?

Waiting for some better weather before I venture into the world of CAF.

I have but I can't say I have drawn any conclusions. Without much light the results could be adversely affected so, like you, really waiting for better weather. Hoping tomorrow might be okay.

Gwyver
19th December 2016, 04:32 PM
...It is a proper, grown-up C-AF system just like a good dslr. It's just a shame that it only works with All points which was the motivation for my post. If it could be restricted to smaller groups of points it would be more effective at picking up the intended target at the start while still making it relatively easy to keep the subject within the group as tracking progresses. ...

Tony,
This relates to precisely the question I raised in this other recent thread
http://e-group.uk.net/forum/showthread.php?p=401386#post401386

specifically:
However, what he (Robin Wong) failed to go on and explain was how, when All AF points are active, you can ensure that the initial AF Cluster acquisition matches your intended subject - particularly in circumstances where the scene includes some high-contrast area on the ground in front of your target.

birdboy
19th December 2016, 06:40 PM
...... I am very much enjoying using C-AF with the new subject tracking algorithm in All-points with AF Area Pointer set to On2 to give the dynamic "dancing" display of focus points. It seems to work very well at isolating the nearest subject.
However, I am somewhat confused about the other AF area selection opportunities.



I am not sure that I understand all the CAF functions now available on the MKII yet. I do not understand what you mean by 'dancing'.

When you say subject tracking do you mean that you are using C-AF+TR?

I briefly tried the C-AF and then switched to C-AF+TR (Tracking) and from the playing I have done in really poor light and low contrast birds (gulls, pigeons and magpies) I am most impressed. I have yet to find a good article on the technical aspects of the MKII AF system so all I can to is play and experiment with settings. I am finding that using the low mulitframe silent shutter (other non silent options does not seem to give the frame rates) with C-AF+TR and Rls Priority C Off gives really quick and accurate focusing. I am even preferring C-AF+TR for birds in trees.

I am not really interested in the number of focus points to select just as long as my first half press locks onto my subject of interest. I have noticed that irrespective of the number of points selected I am able to move the camera quite a bit and it keeps locked onto my chosen subject. What more can one ask of an AF system?

TonyR
19th December 2016, 11:14 PM
I am not sure that I understand all the CAF functions now available on the MKII yet. I do not understand what you mean by 'dancing'.

Select C-AF with All-Points focus areas selected and make sure you have AF Area Pointer set to On2. This is one of the best things about the camera! Multiple AF points get dynamically illuminated to follow your subject. Hence dancing.

When you say subject tracking do you mean that you are using C-AF+TR?

No. That's the point. Just C-AF.

I briefly tried the C-AF and then switched to C-AF+TR (Tracking) and from the playing I have done in really poor light and low contrast birds (gulls, pigeons and magpies) I am most impressed. I have yet to find a good article on the technical aspects of the MKII AF system so all I can to is play and experiment with settings. I am finding that using the low mulitframe silent shutter (other non silent options does not seem to give the frame rates) with C-AF+TR and Rls Priority C Off gives really quick and accurate focusing. I am even preferring C-AF+TR for birds in trees.

I am not really interested in the number of focus points to select just as long as my first half press locks onto my subject of interest. I have noticed that irrespective of the number of points selected I am able to move the camera quite a bit and it keeps locked onto my chosen subject. What more can one ask of an AF system?

Ross the fiddler
20th December 2016, 08:51 AM
I am not sure that I understand all the CAF functions now available on the MKII yet. I do not understand what you mean by 'dancing'.


Select C-AF with All-Points focus areas selected and make sure you have AF Area Pointer set to On2. This is one of the best things about the camera! Multiple AF points get dynamically illuminated to follow your subject. Hence dancing.


I picked up my cousin's D7200 set on Auto (I think) & it behaved like that. I can see the use & advantage in how Olympus use it for their C-AF as shown on the Olympus Australia site (http://www.olympus.com.au/Products/Interchangeable-Lens-Cameras/Olympus-OM-D/E-M1-Mark-II/Features/High-speed-Performance).

Moving-subject-tracking cluster display

A cluster display that moves along with the subject makes it easy to confirm that the subject is continuously in focus.
http://www.olympus.com.au/getattachment/Products/Interchangeable-Lens-Cameras/Olympus-OM-D/E-M1-Mark-II/Features/High-speed-Performance/Controls-for-making-use-of-high-speed-AF/000084960.jpg.aspx?lang=en-AU
When C-AF and All Target are set
When AF Target display is set to ON2

TonyR
20th December 2016, 08:57 AM
I picked up my cousin's D7200 set on Auto (I think) & it behaved like that. I can see the use & advantage in how Olympus use it for their C-AF as shown on the Olympus Australia site (http://www.olympus.com.au/Products/Interchangeable-Lens-Cameras/Olympus-OM-D/E-M1-Mark-II/Features/High-speed-Performance).

Yes, that's it. I expect the tracking works just the same if you don't have AF Area Pointer set to On2. You just wouldn't see it in action.

It is amazingly sensitive. It will pick-up a blue tit at 75m against a sky background or larger subject in front of a busy background. I expect it to be my method of choice for bif.

andym
20th December 2016, 02:13 PM
Went out in the sunshine this morning and got some really good results. I won't post them as it was only gulls flying about but the CAF with all points set seems to work very well.
Took me a while to work out to set the electronic shutter in low frames per second to 10 to get auto-focus to work between each frame.
Didn't want to overtax the mechanical shutter.

Looking forward to trying it on something a bit more interesting.

Bengeo
22nd December 2016, 07:25 PM
Had a good day at RSPB Wallasea Island today trying out C-AF and the dancing display etc. Very pleased with the focusing performance so far, but will play with some fine tuning. I think it would have been much harder to get this shot with the Mark 1.

https://c5.staticflickr.com/1/489/31661428692_41fd3acc30_b.jpg (https://flic.kr/p/QeP6FA)

Short-eared Owl (https://flic.kr/p/QeP6FA) by Andy Johnson (https://www.flickr.com/photos/bengeophotos/), on Flickr

Mrs T
27th December 2016, 09:27 PM
As yesterday was such a lovely day (weather wise) we went to Slimbridge to test out the pro capture and C-AF features of my new E-M1 mark II. I would normally have used the Panasonic 100-400mm but in order to utilise pro-capture I used the Olympus 40-150mm pro plus 1.4 MC-14.

I do have some thought on the pro capture but I'll find the appropriate thread for those.

As I shot over 1,300 pictures that's way too many for here!

This is one of a series of shots (I was already focused on the gull waiting for him to go when someone walked past):

http://www.e-group.uk.net/gallery/data/500/e-Group_11.jpg

For more I have put a gallery in SmugMug and I hope (fingers crossed) this link will work.

https://amandat.smugmug.com/Birds-In-Flight-E-M1-Mark-II-Fir/

These are pretty much SOOC and I have included all the shots from each burst for anyone who is interested. All of these were picked up when they were already in flight (no initial pre-focus).

I found that when there were a whole load of gulls going up the camera was overwhelmed and didn't know what to focus on.

Some of the gulls were coming in a bit slower but when they whizzed by there was no chance of picking them up. Also, some of them seemed either to drift into or out of focus. That may have been down to my attempts to follow them being lacking, but I think the tracking cluster worked really well.

In this collage the robin, swans and goldfinch were also taken when the camera was set to C-AF. The others are all isolated images from pro capture/burst sequences:

http://www.e-group.uk.net/gallery/data/500/Boxing_Day_Slimbridge_Collage.jpg

I was using f4 and auto ISO, so variable shutter speeds.

A lot to learn but I think this is a positive start.

Amanda

brasche
28th December 2016, 04:30 AM
Thanks everyone for the informative discussion.

Coming from an E-M5, I'm finding the E-M1 MKII has a steep learning curve (and until I read this thread I was still uncertain about the AF Area Pointer setting.) So for those curious about CAF-TR, maybe the results of a little test I tried might be valuable.

To test continuous auto focus with tracking (CAF+TR) I had my wife ride her bicycle along the driveway and sidewalk. There are five different sensitivities/modes for tracking and for my tests I used the middle one (default.) Shutter speed was 1000 (to stop motion), aperture was f2.8 (to make minor inaccuracies apparent), and ISO was Auto. The lens was the M.Zuiko 40-150mm Pro zoomed to 150mm. My focus point was a single square at the center of the screen. My shutter was set to mechanical Sequential Low. The weather was clear with patchy clouds. I varied the sensor stabilization modes between Auto to S-IS1 and the Auto ISO fluctuated as my wife rode in and out of the shade.

For my first test I focused on my wife’s face as she rode towards me on the sidewalk. The camera tended to lose focus when my wife abruptly entered deep shade. In more gradual shade transitions the ISO transitioned gracefully and focus was seldom lost. Focus was frequently lost as she passed close to me, both with Auto and S-IS1 stabilization.

For my second test I focused on my wife’s face as she circled back and forth in the driveway. Again, shade was a factor. The camera tracked well when she was approaching but lost focus when passing and never recovered as she rode away. I was pleased at how well Auto ISO adjusted to the shade which assured my wife’s face was correctly exposed. For this test I used S-IS1 image stabilization. This is not the recommended choice for horizontal panning, but it was what worked best when my wife passed me in the previous tests. S-IS2 or Auto would have been the logical choice.

Getting tracking to work consistently is going to take a lot of trial and error (and some wear on the shutter.) I took 500 shots conducting my test. CAF-TR is certainly not point and shoot ready. When the camera was tracking well, a high percentage of the images were “in-focus.” I use quotes because they were acceptably sharp, clearly focused on the subject with obvious bokeh. However, only a few of my shots were tack sharp, maybe 5-10%.

my .02

Mrs T
28th December 2016, 08:11 AM
Your experiment has made me wonder what the difference between C-AF tracking and C-AF using the 9 box cluster display. I guess that with C-AF tracking it uses a single point of focus and with the cluster display you have 9 points.

brian1208
28th December 2016, 10:13 AM
I've been experimenting with CAF and CAF + TR vs my EM-1 standard which was SAF + MF and on results so far now believe that Olympus have delivered what they promised.

With my Panasonic 100-400 on the mk2 I find that both CAF and CAF + TR it locks on as fast as with the SAF but holds that lock even when the birds (only gulls so far, boring times) pass in front of or behind conflicting subjects. So much so that I find I am using CAF with or without tracking in preference to SAF, for both birding and my watersport action work.

(I still find SAF + MF is best for static birds and that trying to use CAF or CAF + tracking when they are in foliage just confuses the system)

I have an album in which I'm logging the output of my tests here

https://www.flickr.com/photos/75445098@N04/albums/72157674435567373

from which a typical result gull tracked following behind a willow tree which was about 40ft from me (full sequence is in the album) Not a great image as the light was pretty poor and we seem to have this constant haze at present:

https://c4.staticflickr.com/1/761/31815933411_9349e6225a_b.jpg (https://flic.kr/p/QtsYy4)PC277848 (https://flic.kr/p/QtsYy4) by Brian Wadie Photographer (https://www.flickr.com/photos/75445098@N04/), on Flickr

Mrs T
28th December 2016, 12:48 PM
Brian,

How many focus points are you using and are you using the tracking focus cluster?

Amanda

brian1208
28th December 2016, 01:10 PM
for this shot I think it was 5 point cross with the green box active so I can watch it track the bird, mind you when I checked after the event the focus point shown isn't where I expected from the apparent position of the tracking box :)

I am finding 5 point or 9 point suit most situations, going to single point if the bird is already in front of a confusing background and all points in a totally open sky

brian1208
28th December 2016, 04:17 PM
I've just got back from a walk with the camera on our local Hengistbury Head reserve and found a limit for using CAF + Tracking.

By around 3.30 the light was getting very low and casting shadow over the harbour, not dark but a noticeable fall off in brightness, at which time CAF + TR was unable to hold lock on gulls at around 50yds distance.


Mind you, even SAF was hunting a bit to grab focus, using 5 point and 9 point focusing

Battery life continues to delight me, this shoot was the second in two days, total individual shots was 2434 and battery showed 34% charge remaining (WIFI and Rear LCD off, some chimping and menu poking)

brian1208
28th December 2016, 10:10 PM
A better example of how CAF + TR holds focus when passing "Attracting" backgrounds (long range shots)

https://c1.staticflickr.com/1/440/31907483616_c6a811b61e_b.jpg (https://flic.kr/p/QByceS)PC280892-2 (https://flic.kr/p/QByceS) by Brian Wadie Photographer (https://www.flickr.com/photos/75445098@N04/), on Flickr


https://c1.staticflickr.com/1/716/31571792480_d040cddbab_b.jpg (https://flic.kr/p/Q6TFXE)PC280896 (https://flic.kr/p/Q6TFXE) by Brian Wadie Photographer (https://www.flickr.com/photos/75445098@N04/), on Flickr

https://c3.staticflickr.com/1/422/31797276202_69375561b6_b.jpg (https://flic.kr/p/QrPmq3)PC280897 (https://flic.kr/p/QrPmq3) by Brian Wadie Photographer (https://www.flickr.com/photos/75445098@N04/), on Flickr