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prefocus question
So I hold the shutter button down halfway to prefocus the shot to decrease shutter lag when I need it NOW like during sports..

Does it hurt the camera to do this routinely?..

Comments (38)

No, in fact it may save wear on the AF motor in the lens..

Brian A...

Comment #1

Wendysue wrote:.

So I hold the shutter button down halfway to prefocus the shot todecrease shutter lag when I need it NOW like during sports..

Does it hurt the camera to do this routinely?.

It doesn't hurt the camera..

I have a question though. Are you using a point & shoot camera, or a DSLR? If you are using a P&S, ignore the rest..

If you are using a DSLR, are you pre-focusing using an AI Servo AF mode, or a One Shot AF mode? It is best to use AI Servo to track your subject, since it will continuously update the AF predictively based on previous subject position. Also, the pre-focused location will most likely only be "close enough" and not as good as it could be if you allowed AF to focus on your subject. Plus, if you are in One Shot AF, you not only lock AF, you generally also lock exposure. In using AI Servo, exposure is set when you press the shutter...

Comment #2

OK, so you pre-focus. Only problem: in many/most(?) cameras this also means simultaneous exposure lock, but locked on what? When your "subject" turns up, will the pre-locked exposure reading be appropriate?..

Comment #3

Hi,.

Im in the "same boat"! Im new to DSLR, Nikon D80. Im taking sports photos (my son's soccer games). When I used the "sports" auto program (the dial on the top left of the camera), the photos usually come out looking horrible, lots of blurry photos. Im able to get some sports shots come out OK with the "auto" setting.What kind of camera do you use?..

Comment #4

I don't know which AF mode is selected when you use the Sport program - I never use it - BUT you need to note that if the camera is in AF-C (Continuous) mode it will take the shot when you press the shutter button, whether or not the subject is actually in focus..

You may find that AF-A gives you better results. I don't know if you can select that in Sports mode..

You'll get better control if you use a program mode such as Shutter priority, set the shutter speed high, and shoot away using the settings of your choice. That's pretty much all that Sports mode does anyway, except that it doesn't allow you to change some settings..

You may also need to learn about the other AF settings - area mode etc..

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Comment #5

Not it does not hurt the camera in ayn way. You can do it for the life of the camera with no worries. That's why it's there.Jules.

Wendysue wrote:.

So I hold the shutter button down halfway to prefocus the shot todecrease shutter lag when I need it NOW like during sports..

Does it hurt the camera to do this routinely?.

Why do you never see birds crash?..

Comment #6

Mikelis wrote:.

OK, so you pre-focus. Only problem: in many/most(?) cameras thisalso means simultaneous exposure lock, but locked on what? When your"subject" turns up, will the pre-locked exposure reading beappropriate?.

If the background - whatever is in view before the subject arrives - is significantly darker or lighter than the subject, then the exposure could easily be wrong. Luckily, in practice you will often pre-focus on grass, or grey rocks, concrete, earth etc., and all of those will give a good neutral exposure that should be ok in most cases...

Comment #7

We don't know which camera you have. I'm gonna make a guess that it's a Fuji or Panasonic camera that takes silent pix (no mirror)..

Wendysue wrote:.

So I hold the shutter button down halfway to prefocus the shot todecrease shutter lag when I need it NOW like during sports..

I understand perfectly what you are saying, but to be pedantic, this technique doesn't affect "shutter lag"...it simply does the AF/expose cycle and holds them. Besides, your camera doesn't have a "shutter" anyway...not in the sense that film cameras did..

Does it hurt the camera to do this routinely?.

Not at all. In fact, you SHOULD half-press all the time on any camera...that's why the manufacturer built it that way..

Charlie DavisNikon 5700 & Sony R1HomePage: http://www.1derful.infoBridge Blog: http://www.here-ugo.com/BridgeBlog/..

Comment #8

Chuxter wrote:.

I understand perfectly what you are saying, but to be pedantic, thistechnique doesn't affect "shutter lag"...it simply does the AF/exposecycle and holds them..

Correct..

Besides, your camera doesn't have a "shutter"anyway...not in the sense that film cameras did..

Incorrect. The vast majority of digicams have a physical shutter. Why? What better way to clear the sensor than to do it in the dark..

Does it hurt the camera to do this routinely?.

I wouldn't say unconditionally "nope" as other posters have said. Every moving part and every motor has a service life, you are using some of it up. But I think it's pretty unlikely you'll have an issue..

Seen in a fortune cookie:Fear is the darkroom where negatives are developed..

Comment #9

Instead of prefocusing, why don'y you use a hyperfocal setup instead? that way you do not have to focus, period; yet everything you shoot during the game is in focus...

Comment #10

Mikelis wrote:.

OK, so you pre-focus. Only problem: in many/most(?) cameras thisalso means simultaneous exposure lock, but locked on what? When your"subject" turns up, will the pre-locked exposure reading beappropriate?.

That was my point about the drawback. When you half press to lock focus and exposure, you keep that same focus plane and exposure setting (ISO/shutter speed/f-stop) regardless of how the scene changes..

As far as whether AE and/or AF lock happens when you half press, it depends on the AF mode and metering mode that you have...

Comment #11

GaryDeM wrote:.

Instead of prefocusing, why don'y you use a hyperfocal setup instead?that way you do not have to focus, period; yet everything you shootduring the game is in focus..

Hyperfocal gets everything "acceptably" sharp, not in sharp focus. There's only one plane of sharpest focus. If hyperfocal focusing got everything in focus, telescopes wouldn't have focus mechanisms..

Also, for most sports, hyperfocal focusing is totally useless. Even if you are in a situation where the focal length, aperture and focus distance conspire to allow you to achieve hyperfocal focusing, you've probably got distractions in the background (stands, spectators, other players, etc) that you'd rather blur out so as to not distract the viewer from the main subject..

Seen in a fortune cookie:Fear is the darkroom where negatives are developed..

Comment #12

GaryDeM wrote:.

Instead of prefocusing, why don'y you use a hyperfocal setup instead?that way you do not have to focus, period; yet everything you shootduring the game is in focus..

You obviously do not shoot sports. This would require that you stop down to a fairly small aperture and cause the shutter speed to drop. If you ever shot sports, you would realize that most shoot wide open with as fast a lens as they can afford at the highest ISO that will give an acceptable print. This is because they need at a minimum a 1/500 shutter speed...

Comment #13

For me landscapes and other outdoor shots, with some rare inside stuff...

Comment #14

OK, so you pre-focus. Only problem: in many/most(?) cameras thisalso means simultaneous exposure lock, but locked on what? When your"subject" turns up, will the pre-locked exposure reading beappropriate?.

Not on my camera (K100D) - you have the option to combine focus lock with AE lock, or not. So you can prefocus, but the exposure won't be set until the shutter fires..

Best wishesMike..

Comment #15

Nickleback wrote:.

Chuxter wrote:.

I understand perfectly what you are saying, but to be pedantic, thistechnique doesn't affect "shutter lag"...it simply does the AF/exposecycle and holds them..

Correct..

Besides, your camera doesn't have a "shutter"anyway...not in the sense that film cameras did..

Incorrect. The vast majority of digicams have a physical shutter.Why? What better way to clear the sensor than to do it in the dark..

Yes, but it's not the same "shutter" referred to in a discussion of "shutter lag". Many cameras close the tiny shutter (in the lens, behind the iris) AFTER the picture has been captured by the sensor, so that it doesn't continue to accumulate photons..

A SHUTTER is the thing that TIMES the exposure. The "shutter" that non-mirror cameras have does NOTHING to time anything. Non-mirror cameras have electronic SHUTTERS..

Does it hurt the camera to do this routinely?.

I wouldn't say unconditionally "nope" as other posters have said.Every moving part and every motor has a service life, you are usingsome of it up. But I think it's pretty unlikely you'll have an issue..

Actually, the "shutter" (in the lens, behind the iris) is held OPEN by a small electro-magnet. When the "shutter" is closed, the magnet is OFF. When you turn off the camera, the little "shutter" electro-magnet is also off and the "shutter" closes. When you press and hold the half-press, the "shutter" has not yet done anything, regardless of whether the "shutter" closes before the pic is taken or after. When you fully press the shutter, then everything associated with taking a picture happens, including the "shutter"..

BTW, it's pretty easy to tell from the specifications whether the "shutter" happens pre- or post-exposure. Cameras which do it pre-exposure have longer lags to the exposure being taken...it takes about 15 ms to close the "shutter" and 10 ms to open it. Cameras which do it post-exposure typically have 5-10 ms lag before exposure...total..

Charlie DavisNikon 5700 & Sony R1HomePage: http://www.1derful.infoBridge Blog: http://www.here-ugo.com/BridgeBlog/..

Comment #16

Dave_s93 wrote:.

GaryDeM wrote:.

Instead of prefocusing, why don'y you use a hyperfocal setup instead?that way you do not have to focus, period; yet everything you shootduring the game is in focus..

You obviously do not shoot sports. This would require that you stopdown to a fairly small aperture and cause the shutter speed to drop.If you ever shot sports, you would realize that most shoot wide openwith as fast a lens as they can afford at the highest ISO that willgive an acceptable print. This is because they need at a minimum a1/500 shutter speed..

All "sports" are not the same. All photographers don't take the same type "sports" pictures. .

Charlie DavisNikon 5700 & Sony R1HomePage: http://www.1derful.infoBridge Blog: http://www.here-ugo.com/BridgeBlog/..

Comment #17

Of course, you have to wait for the mirror to flip on a DSLR which is typically about 100 milliseconds. Dare I say P&S has a disctint advantage here for getting that instant shot but, I suppose, an experienced photographer will anticipate such a delay. Also, a higher shutter speed may be necessary to avoid the effects of mirror 'slap'..

Cheers..

Comment #18

Rocklobster wrote:.

Of course, you have to wait for the mirror to flip on a DSLR which istypically about 100 milliseconds. Dare I say P&S has a disctintadvantage here for getting that instant shot but, I suppose, anexperienced photographer will anticipate such a delay..

You might dare say that but I don't think too many people will agree with you. You can't pick out one aspect of a technology and say that that shows an overall weakness for the whole system. I think it is generally accepted that SLRs have a faster response overall than P&S cameras, when all factors are taken into account, and that "experienced photographers" do not at all "anticipate" a 1/10 second delay - indeed, most human beings do not have responses that good..

Also, a highershutter speed may be necessary to avoid the effects of mirror 'slap'..

On a tripod, perhaps. Hand held? There are much more significant considerations..

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Comment #19

Arrowman wrote:.

Rocklobster wrote:.

Of course, you have to wait for the mirror to flip on a DSLR which istypically about 100 milliseconds. Dare I say P&S has a disctintadvantage here for getting that instant shot but, I suppose, anexperienced photographer will anticipate such a delay..

You might dare say that but I don't think too many people will agreewith you..

One of the issues is that each camera is different and they continue to improve. If you don't actually use/test current designs, it's easy to miss significant improvements. Just in the last 2 years have non-mirror SLR designs appeared with blazing fast image capture (after prefocus). If you haven't experienced one of those cameras, you won't understand..

Yes, I know that "non-mirror SLR" is considered an oxymoron by some..

You can't pick out one aspect of a technology and say thatthat shows an overall weakness for the whole system. I think it isgenerally accepted that SLRs have a faster response overall than P&Scameras, when all factors are taken into account, and that"experienced photographers" do not at all "anticipate" a 1/10 seconddelay - indeed, most human beings do not have responses that good..

Yes, DSLRs have a faster overall response than non-mirror cameras. But, part of that is due to having several processors, working in parallel. Part of that is due to having faster processors. Part of that is due to all DSLRs being higher priced..

If we ever see an EVIL camera design, that uses the fast-multi-processor paradigm, it will be faster than current DSLRs..

I totally disagree about anticipating shutter lag..

Charlie DavisNikon 5700 & Sony R1HomePage: http://www.1derful.infoBridge Blog: http://www.here-ugo.com/BridgeBlog/..

Comment #20

Chuxter wrote:.

Nickleback wrote:.

Incorrect. The vast majority of digicams have a physical shutter.Why? What better way to clear the sensor than to do it in the dark..

Yes, but it's not the same "shutter" referred to in a discussion of"shutter lag"..

The shutter in DSLRs isn't the "shutter" referred to in a discussion of "shutter lag", it's the mirror..

My only point was that digicams do indeed have a shutter. Thanks for agreeing..

Does it hurt the camera to do this routinely?.

I wouldn't say unconditionally "nope" as other posters have said.Every moving part and every motor has a service life, you are usingsome of it up. But I think it's pretty unlikely you'll have an issue..

Actually, the "shutter" (in the lens, behind the iris) is held OPENby a small electro-magnet..

I wasn't talking here about the shutter. Nothing happens with the shutter when you half-press. I was talking about the lens AF mechanism. You've got a motor and (depending on the design) some mechanism to move glass. These parts do wear out..

I said it's unlikely the OP will have an issue, but motors and moving parts do wear out. I've got an old worn out Canon 200/2.8L to prove it..

Seen in a fortune cookie:Fear is the darkroom where negatives are developed..

Comment #21

Chuxter wrote:.

Dave_s93 wrote:.

GaryDeM wrote:.

Instead of prefocusing, why don'y you use a hyperfocal setup instead?that way you do not have to focus, period; yet everything you shootduring the game is in focus..

You obviously do not shoot sports..

All "sports" are not the same. All photographers don't take the same type "sports" pictures. .

Agreed. Find me one situation where hyperfocal focusing is useful in sports, and I'll show you 100 where it is utterly useless..

Seen in a fortune cookie:Fear is the darkroom where negatives are developed..

Comment #22

I didn't mean to start a P&S vs DSLR debate it's just that I see that the mirror is the weakest link in the DSLR design and apart from the Sony R1 (not really a DSLR - no optical viewfinder) I don't know of any other camera that uses an optical viewfinder without a mirror that isn't a rangefinder..

By the way, I do see the benefits of an optical viewfinder but I also see the benefits of 'liveview' and I think that LCD technology (in the viewfinder) will eventually replace the optical viewfinder..

The reason for my view on the mirror delay is that for the particular application that I use a camera for I need an instantaneous shot taken (by computer control - not a finger on the shutter release) with about 10 millisecond delay so I cannot use a DSLR. There is also a focal-plane shutter issue that complicates the issue and this is another reason..

Cheers..

Comment #23

Nickleback wrote:.

Chuxter wrote:.

Nickleback wrote:.

Incorrect. The vast majority of digicams have a physical shutter.Why? What better way to clear the sensor than to do it in the dark..

Yes, but it's not the same "shutter" referred to in a discussion of"shutter lag"..

The shutter in DSLRs isn't the "shutter" referred to in a discussionof "shutter lag", it's the mirror..

A mirror is not a shutter. In a dSLR, the mirror has to flip out of the way before the real shutter can operate. The mirror is what causes most of the "shutter lag" in a dSLR...but it's not the shutter..

My only point was that digicams do indeed have a shutter. Thanks foragreeing..

Yes, but again in a non-mirror camera, the shutter is not a shutter as in mirror-camera. It's a way to block the light falling on the sensor so that the data stored in it can be read out w/o creating more noise. It also is used when long exposures are used, to take a black frame and thus apply NR. But this shutter is NOT used to time exposures as the shutter in dSLRs are. It probably should not be called a shutter. It's a blinder?.

Does it hurt the camera to do this routinely?.

I wouldn't say unconditionally "nope" as other posters have said.Every moving part and every motor has a service life, you are usingsome of it up. But I think it's pretty unlikely you'll have an issue..

Actually, the "shutter" (in the lens, behind the iris) is held OPENby a small electro-magnet..

I wasn't talking here about the shutter. Nothing happens with theshutter when you half-press. I was talking about the lens AFmechanism. You've got a motor and (depending on the design) somemechanism to move glass. These parts do wear out..

Why does half-pressing cause the AF motor to operate more than normal? It seems to me that the camera will AF once and then hold that focus. I realise that some cameras have a Continuous AF setting, but if it is selected, the AF motor is working all the time and half-press will have no adverse affect..

I said it's unlikely the OP will have an issue, but motors and movingparts do wear out. I've got an old worn out Canon 200/2.8L to proveit..

Was it's death due to half-pressing? Or just normal use?.

Charlie DavisNikon 5700 & Sony R1HomePage: http://www.1derful.infoBridge Blog: http://www.here-ugo.com/BridgeBlog/..

Comment #24

Nickleback wrote:.

Chuxter wrote:.

Dave_s93 wrote:.

GaryDeM wrote:.

Instead of prefocusing, why don'y you use a hyperfocal setup instead?that way you do not have to focus, period; yet everything you shootduring the game is in focus..

You obviously do not shoot sports..

All "sports" are not the same. All photographers don't take the same type "sports" pictures. .

Agreed. Find me one situation where hyperfocal focusing is useful insports, and I'll show you 100 where it is utterly useless..

I don't use hyperfocal focusing, but I would not state that it's always useless when taking sports pix. Perhaps just almost worthless? .

Charlie DavisNikon 5700 & Sony R1HomePage: http://www.1derful.infoBridge Blog: http://www.here-ugo.com/BridgeBlog/..

Comment #25

Chuxter wrote:.

A mirror is not a shutter. In a dSLR, the mirror has to flip out ofthe way before the real shutter can operate. The mirror is whatcauses most of the "shutter lag" in a dSLR...but it's not the shutter..

Thanks again for completely agreeing with what I wrote..

My only point was that digicams do indeed have a shutter. Thanks foragreeing..

Yes, but again in a non-mirror camera, the shutter is not a shutteras in mirror-camera..

Again we agree..

Why does half-pressing cause the AF motor to operate more thannormal? It seems to me that the camera will AF once and then holdthat focus..

Do you shoot each time it focuses? Probably not. On cameras where I've been forced to do this, I emulate servo mode by half pressing many times..

I realise that some cameras have a Continuous AF setting,but if it is selected, the AF motor is working all the time andhalf-press will have no adverse affect..

Depends on the camera and how you have set it up. On the default setup on Canon DSLRs in AI Servo, AF doesn't operate until you half press. It stops when you release half press. You can change this with custom functions..

I said it's unlikely the OP will have an issue, but motors and movingparts do wear out. I've got an old worn out Canon 200/2.8L to proveit..

Was it's death due to half-pressing? Or just normal use?.

Servo mode. But as I said, multiple half-presses is the workaround if you are using a camera without servo mode..

Seen in a fortune cookie:Fear is the darkroom where negatives are developed..

Comment #26

Chuxter wrote:.

Nickleback wrote:.

Chuxter wrote:.

Dave_s93 wrote:.

GaryDeM wrote:.

Instead of prefocusing, why don'y you use a hyperfocal setup instead?that way you do not have to focus, period; yet everything you shootduring the game is in focus..

You obviously do not shoot sports..

All "sports" are not the same. All photographers don't take the same type "sports" pictures. .

Agreed. Find me one situation where hyperfocal focusing is useful insports, and I'll show you 100 where it is utterly useless..

I don't use hyperfocal focusing, but I would not state that it'salways useless when taking sports pix. Perhaps just almost worthless?.

I wrote "for most sports, hyperfocal focusing is totally useless"..

Dave_s93 wrote "f you ever shot sports, you would realize that most shoot wide open...".

Neither of us wrote "always", both of us wrote "most"..

Seen in a fortune cookie:Fear is the darkroom where negatives are developed..

Comment #27

Chuxter wrote:.

One of the issues is that each camera is different and they continueto improve. If you don't actually use/test current designs, it's easyto miss significant improvements. Just in the last 2 years havenon-mirror SLR designs appeared with blazing fast image capture(after prefocus). If you haven't experienced one of those cameras,you won't understand..

Yes, I know that "non-mirror SLR" is considered an oxymoron by some..

While I haven't directly experienced the camera(s) of which you speak, I do understand. I am not making the claim that "mirrored" SLRs will never be overtaken for response time. I was only responding to rocklobster's (apaprent) claim that P&S cameras in general - not just this new generation - are superior to SLRs in response time, and that this is down to the mirror. I don't think that was an accurate claim as rocklobster phrased it..

Yes, DSLRs have a faster overall response than non-mirror cameras..

Exactly. rocklobster seemed to be claiming the opposite and that was the point of my post..

If we ever see an EVIL camera design, that uses thefast-multi-processor paradigm, it will be faster than current DSLRs..

Of course..

I totally disagree about anticipating shutter lag..

Let me clarify that..

Of course an experienced photographer will anticipate shutter lag, whichever camera they are using. My point is that there is no difference between and SLR and a P&S in that respect. rocklobster seemed to be saying that an experienced photographer will get around the lag due to the mirror (as opposed to the total lag, whatever it is, for whatever camera) with good anticipation. Apart from anything else, at 100 milliseconds the mirror delay is at the limit of human reaction times as far as I know, and I don't think too many people, experienced or not, would be capable of such precise reaction time. Some people (photographers) are better than others of course..

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Comment #28

Rocklobster wrote:.

The reason for my view on the mirror delay is that for the particularapplication that I use a camera for I need an instantaneous shottaken (by computer control - not a finger on the shutter release)with about 10 millisecond delay so I cannot use a DSLR..

Well that's a completely different (and highly specialised) situation, then..

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Comment #29

Arrowman wrote:.

Chuxter wrote:.

One of the issues is that each camera is different and they continueto improve. If you don't actually use/test current designs, it's easyto miss significant improvements. Just in the last 2 years havenon-mirror SLR designs appeared with blazing fast image capture(after prefocus). If you haven't experienced one of those cameras,you won't understand..

Yes, I know that "non-mirror SLR" is considered an oxymoron by some..

While I haven't directly experienced the camera(s) of which youspeak, I do understand. I am not making the claim that "mirrored"SLRs will never be overtaken for response time. I was onlyresponding to rocklobster's (apaprent) claim that P&S cameras ingeneral - not just this new generation - are superior to SLRs inresponse time, and that this is down to the mirror. I don't thinkthat was an accurate claim as rocklobster phrased it..

I think the three of us are in general agreement, but perhaps not communicating well. Mirror cameras with phase AF focus faster but have a longer delay before the shutter operates. Non-mirror cameras with contrast AF focus slower but have a shorter delay before they capture the image. It was clear to me that rocklobster was concentrating on the delay before image capture...after prefocus..

Yes, DSLRs have a faster overall response than non-mirror cameras..

Exactly. rocklobster seemed to be claiming the opposite and that wasthe point of my post..

I think you mis-read what he said..

I totally disagree about anticipating shutter lag..

Let me clarify that..

Of course an experienced photographer will anticipate shutter lag,whichever camera they are using..

I agree. They do this w/o conciously thinking about it..

My point is that there is no difference between and SLR and a P&S in thatrespect..

I wouldn't say "no" difference..

Rocklobsterseemed to be saying that an experienced photographer will get aroundthe lag due to the mirror (as opposed to the total lag, whatever itis, for whatever camera) with good anticipation..

Yes, I think that's what he was saying..

Apart from anythingelse, at 100 milliseconds the mirror delay is at the limit of humanreaction times as far as I know, and I don't think too many people,experienced or not, would be capable of such precise reaction time.Some people (photographers) are better than others of course..

The classic example of this is human foot races, where in the past, three judges stood at the finish line and each timed the winner with mechanical stopwatches. Then they averaged the results and rounded the time to 1/5 second. Having been one of those judges, in fact often the 3 judges times were in stunning agreement...often to a few thousandths of a second!.

The difficulty with a foot race is that runners change posture (lean) and swing their arms and the difficulty is anticipating which part of which runner crosses first. Often this is difficult to do in real-time..

At an automobile race (timed that too), it's MUCH easier to be accurate and consistent..

I beileve that sports photographers get quite good at anticipating when the ball arrives. Compensating for a 100 ms "shutter lag" is quite easy, if you relax and let your right hemisphere do it. Musicians (keyboards) have an uncanny ability to play many rapid notes with timing accuracy...after years of practice. Yep, not exactly the same thing, but it indicates that the right hemisphere can do amazing things..

Charlie DavisNikon 5700 & Sony R1HomePage: http://www.1derful.infoBridge Blog: http://www.here-ugo.com/BridgeBlog/..

Comment #30

Nickleback wrote:.

Chuxter wrote:.

A mirror is not a shutter. In a dSLR, the mirror has to flip out ofthe way before the real shutter can operate. The mirror is whatcauses most of the "shutter lag" in a dSLR...but it's not the shutter..

Thanks again for completely agreeing with what I wrote..

You're welcome..

Why does half-pressing cause the AF motor to operate more thannormal? It seems to me that the camera will AF once and then holdthat focus..

Do you shoot each time it focuses? Probably not. On cameras whereI've been forced to do this, I emulate servo mode by half pressingmany times..

I try to NOT do this (push to the half-press position), since if if do, I can't take a picture while the camera is doing AF. There are exceptions...I sometimes "jump the gun" and then realize the picture I want is going to be later...I sometimes fail to concentrate and accidently release to much pressure and loose half-press..

I realise that some cameras have a Continuous AF setting,but if it is selected, the AF motor is working all the time andhalf-press will have no adverse affect..

Depends on the camera and how you have set it up. On the defaultsetup on Canon DSLRs in AI Servo, AF doesn't operate until you halfpress. It stops when you release half press. You can change thiswith custom functions..

I agree..

I said it's unlikely the OP will have an issue, but motors and movingparts do wear out. I've got an old worn out Canon 200/2.8L to proveit..

Was it's death due to half-pressing? Or just normal use?.

Servo mode. But as I said, multiple half-presses is the workaroundif you are using a camera without servo mode..

OK. Good to know..

Charlie DavisNikon 5700 & Sony R1HomePage: http://www.1derful.infoBridge Blog: http://www.here-ugo.com/BridgeBlog/..

Comment #31

Chuxter wrote:.

Nickleback wrote:.

On cameras whereI've been forced to do this, I emulate servo mode by half pressingmany times..

I try to NOT do this (push to the half-press position), since if ifdo, I can't take a picture while the camera is doing AF..

That's the whole point of using half-press when shooting moving subjects on a camera without servo AF. You acquire focus before shooting, and hopefully you've got a short amount of time where focus is still good enough and you can take the shot with much less delay. If the subject gets out of focus you half press again. Repeat until you get to the point where you want to take the shot(s)..

The other choices are half press and take the shot, even if it isn't what you want or the focus isn't on your subject. You'll fill up your memory cards with junk shots. Or full press with full focus delay, meaning you'll probably miss the shot..

Seen in a fortune cookie:Fear is the darkroom where negatives are developed..

Comment #32

I suspect we are in violent agreement here, even if we express ourselves, or prioritise different aspects, differently!.

Cheers..

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Comment #33

But I wonder if WendySue now has a "violent" understanding of the differences we are in agreement about? That's the goal here on the BQF....

Arrowman wrote:.

I suspect we are in violent agreement here, even if we expressourselves, or prioritise different aspects, differently!.

Cheers..

Charlie DavisNikon 5700 & Sony R1HomePage: http://www.1derful.infoBridge Blog: http://www.here-ugo.com/BridgeBlog/..

Comment #34

Sorry I caused such a stir..

My point is that P&S cameras are not inherently slower than DSLR cameras. They just have slower processors and other parts that run slower because they are cheaper. I (and probably yourself) lament that they didn't use a faster prcessor for the Sony R1 (not strictly a P&S by the way)..

Trouble is that the definition of shutter lag varies depending on who you talk to. God forbid if we should break it up in to AF lag, AE lag, mirror lag, CCD lag and processor lag..

Cheers..

Comment #35

Rocklobster wrote:.

Sorry I caused such a stir..

My point is that P&S cameras are not inherently slower than DSLRcameras. They just have slower processors and other parts that runslower because they are cheaper. I (and probably yourself) lamentthat they didn't use a faster prcessor for the Sony R1 (not strictlya P&S by the way)..

Sony designed the R1 to be their first dSLR. But near it's release to market, they bought K-M and so decided to NOT call the R1 a dSLR. I guess some people believed them?.

Trouble is that the definition of shutter lag varies depending on whoyou talk to. God forbid if we should break it up in to AF lag, AElag, mirror lag, CCD lag and processor lag..

This misunderstanding is huge. Even the brilliant review sites we frequent don't agree and probably don't understand what is going on in most cameras. I like your list (above) except it should be "sensor lag" and probably need to add "EVF lag" as some cameras seem to wait until an EVF frame is complete before initiating image capture. Also, non-mirror cameras have a small "shutter" in the lens that darkens the sensor during image transfer...this little "shutter" has a delay associated with it..

I wish somebody would actually TEST cameras. It would be very beneficial to see a time-line on each camera from the start of AF to the appearance of the image on the LCD or EVF. It might look something like this:.

Image control:Zoom outZoom 100%Zoom inExpand AllOpen in new window.

I think most reviewers agree that the full "shutter" lag is from pressing the shutter button until the exposure actually starts. In this sense, it probably should be called "exposure lag", as most cameras don't have a shutter anymore. Yes, the do, but it's not the same...more of a blinder to block light so the sensor can be readout in the dark..

Some reviewers have in the past timed from shutter button depression until the image appeared on the LCD or EVF. This was clearly wrong..

Most of the confusion seems to be in understanding that there are two important and separate times involved. Phil calls them S1 and S2. They are the time needed to AF, AE, & WB and the time needed to start the exposure after the S1 time has been done..

Note that camera A has a slow AF and does the AE/WB after the AF is complete (only one processor), but can start the exposure immediately afterward. It has an S1 delay of about 257 mS and an S2 delay of about 5 mS..

In contrast, camera B has a fast AF and does AE/WB in parallel (several processors) but has to wait until the mirror flips up to start the exposure. It has an S1 delay of about 200 mS and an S2 delay of about 100 mS..

Charlie DavisNikon 5700 & Sony R1HomePage: http://www.1derful.infoBridge Blog: http://www.here-ugo.com/BridgeBlog/..

Comment #36

Displaying these times in a graphical form would be by far the best method but really what do you need to know from a photographers point of view?.

1. The AF/AE/WB time - First part of shutter button press2. The prefocussed to sensor exposure time - Final press of button and,3. How long before you can take the next shot.

And, not to be forgotten, how the various modes affect these times:.

High-speed modeBurst modeContinuous modeContinuous AF modeManual mode... the list goes on........

Cheers..

Comment #37

Rocklobster wrote:.

Displaying these times in a graphical form would be by far the bestmethod but really what do you need to know from a photographers pointof view?.

Applications differ. Don't assume that because you don't need all this that everyone else doesn't...not that you said that. This is a camera equipment review site. There is LOTS of stuff in the review that I'm not really interested in, but I assume there are others that find it invaluable..

Seeing this information graphically is very educational...that's the role of DPR. There are many people that don't have a clue how a camera really works. They don't understand why one camera does something and another doesn't. The order of internal events and serial vs parallel is important to understanding how/why a specific camera does what it does..

For example, it would be VERY interesting to see how the various "live view" dSLR manufacturers actually decided to do everything when "live view" is selected. It's obvious they don't do it the same..

1. The AF/AE/WB time - First part of shutter button press2. The prefocussed to sensor exposure time - Final press of button and,3. How long before you can take the next shot.

This is reported. I think manufacturers should include this in their specifications. Perhaps Oly with their E-3 has started something? The only issue is that with a dSLR, there are LOTS of variables...the choice of lens, it's FL, it's aperture, and various camera settings all have marked effects on these times. I think it's time for some brilliant camera designer to include a "black box" inside their camera to simply record when these major events take place. If you are interested, like Phil is, you can display the results of recent pix. Heck, an even better approach would be to save it in the EXIF data...that way you know exactly how the camera responded for each pic.



Similarly, in VR/IS cameras, I'd like to see data about motion included in the "black box" or EXIF..

And, not to be forgotten, how the various modes affect these times:.

High-speed modeBurst modeContinuous modeContinuous AF modeManual mode... the list goes on........

Yep..

Charlie DavisNikon 5700 & Sony R1HomePage: http://www.1derful.infoBridge Blog: http://www.here-ugo.com/BridgeBlog/..

Comment #38

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