LTZ470
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If you haven't used a GH2 then you should...
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AF speed... a matter of perspective.
- Thread starter Marla2008
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Amin Sabet
Veteran Member
With a static subject and adequate light, my E-P3 and 45/1.8 locks faster than my D700 and AF-D 85/1.4 did.
In very low light, my GH2 and 14/2.5 locked quickly whereas my K5 and DA21 as well as my dad's 5D II and 24-70L kept hunting.
With static subject, K5 and DA21 also focused slower than GH2 and Pana 14/2.5. K5 and DA70 also focused slower than E-P3 and Oly 45.
I've been testing a Canon G1X lately, and the AF is positively lethargic compared to any of the above cameras.
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In very low light, my GH2 and 14/2.5 locked quickly whereas my K5 and DA21 as well as my dad's 5D II and 24-70L kept hunting.
With static subject, K5 and DA21 also focused slower than GH2 and Pana 14/2.5. K5 and DA70 also focused slower than E-P3 and Oly 45.
I've been testing a Canon G1X lately, and the AF is positively lethargic compared to any of the above cameras.
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I have an E-P3 and a GH2 and I agree, both are awful for moving targets.
My D700, D3 and D3x are far, far better.
That's not to say you can't get nice action shots with m4/3 gear, it's just a lot harder than with many other cameras.
I greatly prefer even my M9 over any m4/3 for moving subjects.
I am hopeful that the next generation of m4/3 will begin to overcome this deficit.
Best,
Bill
My D700, D3 and D3x are far, far better.
That's not to say you can't get nice action shots with m4/3 gear, it's just a lot harder than with many other cameras.
I greatly prefer even my M9 over any m4/3 for moving subjects.
I am hopeful that the next generation of m4/3 will begin to overcome this deficit.
Best,
Bill
LTZ470
Forum Pro
Louis_Dobson
Forum Pro
I often find conversations on DP Review become dialogues of the deaf...
Marla is saying the AF is slow compared to her old D700.
We all three of us have roughly the same kit, so we know that what she is saying cannot be correct. We can assume she is not making it up. We look at picture and we see she is trying to capture a subject whose distance is changing relative to the camera.
So in fact she is saying that CDAF is slower to get a (supposed) lock on a moving subject than PDAF.
This is correct, but does mean the GX1's af is "slower" than the D700. This is a special circumstance because:
1) The nature of PDAF means that the D700 in S-AF mode would be getting an invalid lock.
2) One would normally use C-AF, and we already know that is a mirrorless weak point.
So, no, the GX1 does not focus more slowly than a D700 - in normal circumstances.
http://www.flickr.com/photos/acam
http://thegentlemansnapper.blogspot.com
Marla is saying the AF is slow compared to her old D700.
We all three of us have roughly the same kit, so we know that what she is saying cannot be correct. We can assume she is not making it up. We look at picture and we see she is trying to capture a subject whose distance is changing relative to the camera.
So in fact she is saying that CDAF is slower to get a (supposed) lock on a moving subject than PDAF.
This is correct, but does mean the GX1's af is "slower" than the D700. This is a special circumstance because:
1) The nature of PDAF means that the D700 in S-AF mode would be getting an invalid lock.
2) One would normally use C-AF, and we already know that is a mirrorless weak point.
So, no, the GX1 does not focus more slowly than a D700 - in normal circumstances.
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http://www.flickr.com/photos/acam
http://thegentlemansnapper.blogspot.com
Adventsam
Senior Member
Has anybody got there GH2 configured for half-press, I was back at the car after a walk on Sat. and switched to half-press release, af-s, and was snapping at motorbikes and cars at aprox 60mph+, I was situated just after a blind bend and with my 14-140 at aprox mid tele was able to aquire af instantly as soon as I pushed for focus and bang the camera fired. If you care to give this a try too, not sure if gx1 has this feature but I think it has and touch release from the lcd, although thats not really suitable for fast moving subjects.
Detail Man
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Without any intended reference to this particular thread (or it's individual participants), I find your "dialogues of the deaf" positively poetic! ...
... A corollary being "shared visions of the blind"! 
Detail Man
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Nice, LT ! All from bursting in GH2 AFC mode ? What is the approximate percentage yield realized ?
Bilgy_no1
Senior Member
Not all DSLRs have the same AF-performance either. I'm not convinced the comparison of a high spec full frame DSLR to an enthousiast level CSC is a useful one. Olympus and Panasonic are really making progress with AF: AF-S is already faster than DSLRs, AF-C is getting better. But the fact that they have not yet introduced real upmarket models indicates that they do not yet feel that CDAF can replace PDAF for all purposes. Olympus have expressly stated that there is still a need for a pro-grade body like the E-5.
The E-M5 hangs around in the same class as the D90/D7000/60D, and that's what we should be comparing to when it comes out.
And how much difference does the lens make: think about a DX kit lens vs. high quality USM lens?
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http://www.flickr.com/photos/bilgy_no1
The E-M5 hangs around in the same class as the D90/D7000/60D, and that's what we should be comparing to when it comes out.
And how much difference does the lens make: think about a DX kit lens vs. high quality USM lens?
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http://www.flickr.com/photos/bilgy_no1
duartix
Senior Member
I have to share something from the GH2 + M-Zuiko 45mm F1.8 on the weekend...
Two 6 year olds playing badminton (and they were really bad, so they were mostly running around).
Tried S-AF, focus tracking, Face Detection, the sh*t. I'd say 50% were OOF. In a desperate move I committed the biggest heresy you can think off... yes, I switched to Touch Shutter! :O
~95% hits.
I will say no more...
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Duarte Bruno
Louis_Dobson
Forum Pro
It's not the normal test.
The GH2 / 45 f1.8 combo focuses as fast or faster than a D700, I promise you. I've tried both sat side by side on many occasions.
http://www.flickr.com/photos/acam
http://thegentlemansnapper.blogspot.com
The GH2 / 45 f1.8 combo focuses as fast or faster than a D700, I promise you. I've tried both sat side by side on many occasions.
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http://www.flickr.com/photos/acam
http://thegentlemansnapper.blogspot.com
Louis_Dobson
Forum Pro
GH2 matches or beats the D3 here. Having said that, it hardly matters, both are blisteringly fast. MFT is a dog for moving subjects still.
http://www.flickr.com/photos/acam
http://thegentlemansnapper.blogspot.com
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http://www.flickr.com/photos/acam
http://thegentlemansnapper.blogspot.com
Marla2008
Senior Member
I guess Louis found the explanation. Since CDAF accepts no approximation, it won't lock on a moving subject, the way PDAF does. And I might not have set the GX-1 in the most efficient manner. Up close I'll use Face Recognition which works good but fidgets if subject is not static.
I've also experimented with C-AF a little and it has 2 problems. First it doesn't lock always were it should (or it does but then strays away from initial point and tracks another part of the image !). And even when locked on the proper thing, it pains to keep up.
So usually I use 1 zone AF that I set with the touch screen. I have turned off Quick AF (which pre focuses non stop) for power saving reasons. Should I turn in back On ?
Any tips to improve my AF experience is welcome, I'm new to m4/3 and maybe there's still user error involved..
The usual scenario would be focusing on the face of a child that doesn't necessarily moves fast, but tends to not be still.
I've also experimented with C-AF a little and it has 2 problems. First it doesn't lock always were it should (or it does but then strays away from initial point and tracks another part of the image !). And even when locked on the proper thing, it pains to keep up.
So usually I use 1 zone AF that I set with the touch screen. I have turned off Quick AF (which pre focuses non stop) for power saving reasons. Should I turn in back On ?
Any tips to improve my AF experience is welcome, I'm new to m4/3 and maybe there's still user error involved..
The usual scenario would be focusing on the face of a child that doesn't necessarily moves fast, but tends to not be still.
Ulfric M Douglas
Senior Member
As you've seen from many replies, the right m4/3rds body with the right lens can be faster than many DSLR&lens combinations, just because your technique with your camera and your lens isn't lightining don't tar all with the same brush.
For example, were you to replace your GX1 with an e-P3(for example) and the Olympus 45mmF1.8 lens you may have find this thread irrelevant.
By the way, I've never heard of the Lumix 25mm lens as being a particularly swift focuser.
E
Ednaz
Guest
I agree wholeheartedly. I was trained in the film DSLR world by sports photographers, and by trained I mean doing actual drills that simulated, for example, being field side at a football game, where you may be on the quarterback at snap then to a wide receiver match up then back to the halfback in the backfield all in a second or two. That rapid movement from subject to subject at different distances and angles and speed is something that m4/3 struggles with - the acquisition stage with subjects that are unpredictable, or where you need to cover a big area with split-second acquisition and shooting.
With EVF, even humans struggle because the EVF takes time to settle. One trick I've used with m4/3 that speeds acquisition is to work both eyes open, something not as necessary with an optical finder. It means that I get back the half second, roughly, it takes to perceive what's in the EVF once it settles down, but that's mostly made me more aware of how long it takes. The camera needs its perception of the subject area to settle down, and it isn't able to get to work focusing until it does, which I find to be a fraction longer than it takes for the EVF to settle.
Actual focusing speed, once you've acquired the target, on m4/3 has gotten significantly better. It's still not as fast as a DSLR, and since shooting with the 25 1.4, I'm noticing not as precise. When your total DOF is measured in single digit inches, precision matters, and I've noticed that if I do a five shot sequence of a subject (like one of my dogs, close up) each shot will have a slightly different focus point. Not a problem at f5.6 or f8, but at f1.4, often the difference between keeper (eyes in focus) or loss (nose end in focus.)
Then there's tracking. I find tracking to be pretty good if I'm camera steady and the subject is moving around in the frame. If I'm tracking the subject, because it's moving around, I find tracking to be way iffy. Mostly because moving to track a subject causes the image to blur because of EVF refresh speeds.
I've spend hours doing my speed drills with m4/3, and have found several tricks and adaptations (like two eye shooting) that have improved things, but not enough for me to risk using the m4/3 when I know I HAVE to have the right image. Shooting some events, like cultural ceremonies, where the total event may last a few minutes, and things are happening all over the place around you, DSLRs have some critical capabilities that get the shot.
With EVF, even humans struggle because the EVF takes time to settle. One trick I've used with m4/3 that speeds acquisition is to work both eyes open, something not as necessary with an optical finder. It means that I get back the half second, roughly, it takes to perceive what's in the EVF once it settles down, but that's mostly made me more aware of how long it takes. The camera needs its perception of the subject area to settle down, and it isn't able to get to work focusing until it does, which I find to be a fraction longer than it takes for the EVF to settle.
Actual focusing speed, once you've acquired the target, on m4/3 has gotten significantly better. It's still not as fast as a DSLR, and since shooting with the 25 1.4, I'm noticing not as precise. When your total DOF is measured in single digit inches, precision matters, and I've noticed that if I do a five shot sequence of a subject (like one of my dogs, close up) each shot will have a slightly different focus point. Not a problem at f5.6 or f8, but at f1.4, often the difference between keeper (eyes in focus) or loss (nose end in focus.)
Then there's tracking. I find tracking to be pretty good if I'm camera steady and the subject is moving around in the frame. If I'm tracking the subject, because it's moving around, I find tracking to be way iffy. Mostly because moving to track a subject causes the image to blur because of EVF refresh speeds.
I've spend hours doing my speed drills with m4/3, and have found several tricks and adaptations (like two eye shooting) that have improved things, but not enough for me to risk using the m4/3 when I know I HAVE to have the right image. Shooting some events, like cultural ceremonies, where the total event may last a few minutes, and things are happening all over the place around you, DSLRs have some critical capabilities that get the shot.
Olympus promised a better (and faster) AF tracking on the EM-5, thanks to a new super secret algorithm. I'm curious to see if it's just marketing talk or not...I hope EM-5 still goes a step further in this department, that'd be a great excuse to upgrade
Detail Man
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Setter Dog 's experience with C-AF (or AFC) on a GH2 may interest you:
http://forums.dpreview.com/forums/read.asp?forum=1041&message=40369323
I wonder whether it would modify/improve the performance when shooting bursts in C-AF mode ?
Marla2008
Senior Member
Thx a lot for the link, I'm gonna study that in... Detail
One interesting thing : in C-AF I first thought that I had to keep shutter half-pressed to keep focus locked on my target (the way a DSLR behaves, and what seems pretty intuitive to me). My mistake ! Apparently the way it works is : put your focus point where you want it, half press until box becomes green, then let go of shutter and focus point will (hopefully) follow your target around (except many times it screws up doing so). When you want to take the shot, fully depress shutter (works every other time, or refocuses on something else and screws your shot altogether)...
To top that, the Panasonic manual is next to useless at explaining the different settings in detail. If anybody could advise a blog or book going over the GX-1 in decent depth, I'd live that
One interesting thing : in C-AF I first thought that I had to keep shutter half-pressed to keep focus locked on my target (the way a DSLR behaves, and what seems pretty intuitive to me). My mistake ! Apparently the way it works is : put your focus point where you want it, half press until box becomes green, then let go of shutter and focus point will (hopefully) follow your target around (except many times it screws up doing so). When you want to take the shot, fully depress shutter (works every other time, or refocuses on something else and screws your shot altogether)...
To top that, the Panasonic manual is next to useless at explaining the different settings in detail. If anybody could advise a blog or book going over the GX-1 in decent depth, I'd live that
LTZ470
Forum Pro
Hi DM...can't remember. but I did shoot a few 100 shots for 5-6 keepers many more my wife liked, but I would not keep them slightly OOF, comp, or eyes hid...I did not know what I was doing at the time...when i go back to Galveston I'll get down on the beach where I can shoot easier...these were shot at the hotel of fly by's...when i got to the beach I only took the EPL2 and I got several shots out of just a few clicks quickly form the EPL2 that is SLOW! So if I would have taken the GH2 down to the beach I would have yielded many more keepers AND much better quality...
I went back into the folder and I had taken less than 200 shots of Pelicans in flight...here are some I pulled up and PP'd just now that were marginal...this was my first time out on the coast shooting and I wasn't prepared and in a rush actually because I was on business...
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