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Author Topic: MLU again  (Read 12399 times)
wolfy
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« on: November 23, 2007, 10:27:37 AM »
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Note - This post is copied from one which is out-of-place, having evolved during discussion in another thread.  The subject had turned to MLU's desirability for those seeking best-quality images. Here:

http://luminous-landscape.com/forum/index....c=20367&st=200&



Those with little use for MLU (or who BELIEVE that there is little use for it,) might consider these points:

1. A programmed camera is not always an effective substitute for a thinking photographer.  This means that when a "self-timer" is controlling the moment of capture (2 sec. delay?, 10 sec. delay? 30 sec. shut-down?), any sort of peak-moment capture is reduced to a wild guess. Hardly a "professional" feature. IMO, this is no "work-around. It is a poor imitation of user-control.

 [ Here are four (A-D)of many possible scenarios;
 
A.  You are using a tripod mounted long tele with remote release pre-focused on a distant offshore rock upon which waves break spectacularly. You wish the rocks(mermaid, whatever,) to be as sharp as possible, with whatever softness to the water you may create by your choice of shutter speed. You wish to capture the moment of peak splash height, like ...,...,...NOW! Oops, ...the self timer missed it by a mile (maybe because it "timed-out", un-noticed after some designer-decided 30 sec. limit).

B. Same set-up, different target. The osprey/eagle/pterodactyl is about to land on the edge of the nest, fish-in-beak, wings spread and claws out-stretched for touchdown, matching the outstretched necks of the fledglings straining to receive dinner. Another "NOW!" moment. Is the blind self-timer going to guess it correctly? My Donkey!]

C. Target - birds at feeder. Anyone know how quickly flitting birds can move from the "perfect pose" shot to a wasted one? The camera doesn't, that's for sure.

D. Two wild mountain rams at the moment of butting impact, dust flying from foreheads, some  hooves off ground? A distant, very "Now!"  moment. Perhaps capturable by YOU (especially with 8-10 FPS), ...but not with programmed interference form a self-timer.

Control means control!

2. Opinions differ as to MLU usefulness at any given shutter speed. However, anytime there is a POTENTIAL benefit from MLU, there is no arguing this fact:
Reduced or "damped" mirror vibration is not the same thing as ELIMINATED mirror vibration. Canon's providing real MLU would "admit" nothing except this incontrovertible fact. [ As to the nebulosity of MLU usefulness -- For an in-depth study of MLU effectiveness under  various conditions, timings, focal-lengths, etc. done by a serious, careful and skilled photographer, see first link below.]

3. Real user-controlled MLU was not limited to only the "top" models, at least in the case of Minolta in the early 70's (late 60's?). The SRT line was below their briefly offered "pro" model (can't remember the model designation).


There have been numerous studies of MLU usefulness. Here is a link to what I  consider one of the most thorough (The entire site is well worth visiting, ...and there is some intriguing Nikon vs. Canon opinion from this experienced pro.)

Fritz Polking index (See Workshop I - "Sharp Photographs"): http://www.poelking.com/index_e.htm


Sadly, this renowned photographer/author is now deceased. Notice is here:

Polking Passing (July 23, '07)-
http://www.digitalphotopro.com/news/master...lking-dies.html

Bottom line for me;

Give us back real user controlled (and simple) MLU. "Flip",...it's up. "Flip" it's down. I'll decide when.
 
Canon, this user will trade you one facial-recognition "feature" for one real MLU anyday!

Opinion. Correction welcome, as always,
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Ray
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« Reply #1 on: November 23, 2007, 12:06:48 PM »
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A.  You are using a tripod mounted long tele with remote release pre-focused on a distant offshore rock upon which waves break spectacularly. You wish the rocks(mermaid, whatever,) to be as sharp as possible, with whatever softness to the water you may create by your choice of shutter speed. You wish to capture the moment of peak splash height, like ...,...,...NOW! Oops, ...the self timer missed it by a mile (maybe because it "timed-out", un-noticed after some designer-decided 30 sec. limit).

[a href=\"index.php?act=findpost&pid=155220\"][{POST_SNAPBACK}][/a]

Sorry Wolfy, that just won't wash. Mermaids never keep still. They're always wiggling their tail and preening themselves. It would not be a good idea to use a slow shutter speed on them.

I've got no argument against the usefulness of MLU. I always use it with shutter speeds of less than 1/60th on tripod, just to be sure to be sure.

I also agree completely that an auto timer has serious disadvantages for MLU purposes, but it's better than nothing. All Canon's professional and prosumer cameras have full MLU. The 300D didn't and probably the 400D doesn't. I haven't checked.

I personally would prefer to see the MLU option say under the auto-bracketing option on the first page of the menu rather than custom function #12. But it's no big deal for me, maybe because I don't use a tripod often. I'm always excited by new ways I can avoid using a tripod, such as CS3's excellent auto-alignment feature which opens up the opportunity for hand-held bracketing.

I have to assume that Canon does its own market research and I can only make a wild guess at the percentage of DSLR owners who use MLU, but it could be something like 1% on a regular basis; 5% occaisionally and 94% never.

I don't expect the world to organise itself around my wishes, you know.  
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wolfy
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« Reply #2 on: November 23, 2007, 12:17:33 PM »
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Sorry Wolfy, that just won't wash. Mermaids never keep still. They're always wiggling their tail and preening themselves.
...
 All Canon's professional and prosumer cameras have full MLU.
[a href=\"index.php?act=findpost&pid=155238\"][{POST_SNAPBACK}][/a]



The preening I can do without,...but the tail wiggling sounds good. I like it on terramaids!  

 
Please describe "full" MLU with respect to what I called "real" MLU (Up when I say, down when I say, shoot when I say).[I do not have a Canon "pro" camera. Was set to jump on the 1DIII, when all the AF discussion broke out,...still waiting for the dust to settle.]


If "full" MLU is the equivalent of old-time user-controlled MLU, for shots such as the examples I gave, ...then what is Michael always going-on about?

[The following answer apperared in the other thread while I was back over here. The musical chairs chase will hopefully end with the topic firmly moved to this forum.   ]

"Full MLU, I suppose is what I've got on my D60, 20D and 5D. Having set the custom function to 'enable' MLU, one presses the shutter button once to flip up and lock the mirror; one waits until the vibrating tripod legs have stabilised and then presses the shutter a second time which begins the exposure. When the exposure has finished, the mirror flips back down automatically and one is ready for the next shot."



Thanks,
« Last Edit: November 23, 2007, 12:24:23 PM by wolfy » Logged
Ray
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« Reply #3 on: November 23, 2007, 12:24:50 PM »
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Hey! Let's keep all replies on this thread then.


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The preening I can do without,...but the tail wiggling sounds good. I like it on terramaids!   

Please describe "full" MLU with respect to what I called "real" MLU (Up when I say, down when I say, shoot when I say).

[I do not have a Canon "pro" camera. Was set to jump on the 1DIII, when all the AF discussion broke out,...still waiting for the dust to settle.]

If "full" MLU is the equivalent of old-time user-controlled MLU, for shots such as the examples I gave, ...then what is Michael always going-on about? (Maybe the other forum is the place to respond?)

Thanks,
[a href=\"index.php?act=findpost&pid=155239\"][{POST_SNAPBACK}][/a]

Full MLU, I suppose, is what I've got on my D60, 20D and 5D. Having set the custom function to 'enable' MLU, one presses the shutter button once to flip up and lock the mirror; one waits until the vibrating tripod legs have stabilised and then presses the shutter a second time which begins the exposure. When the exposure has finished, the mirror flips back down automatically and one is ready for the next shot.
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wolfy
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« Reply #4 on: November 23, 2007, 12:32:59 PM »
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"Full MLU, I suppose is what I've got on my D60, 20D and 5D. Having set the custom function to 'enable' MLU, one presses the shutter button once to flip up and lock the mirror; one waits until the vibrating tripod legs have stabilised and then presses the shutter a second time which begins the exposure. When the exposure has finished, the mirror flips back down automatically and one is ready for the next shot."
[a href=\"index.php?act=findpost&pid=155241\"][{POST_SNAPBACK}][/a]

Ray, doesn't this "1st button pressed/mirror up/ camera ready" state end with an auto shut-off after a set time lapse, as implied in my examples?

This means that if "wait time" happens to exceed the programming, one must costantly monitor to see if the 1st press needs to be repeated. Hopefully the anticipated "peak moment" would not occur while one was in the midst of the clear/reset "fiddling".

A simple mechanical MLU does not require any such monitoring/resetting, and being mechanical, needn't add battery-use (or sensor/display heating?) issues.

Just let ME do it! What's wrong with that picture?

Comments?
« Last Edit: November 23, 2007, 12:40:09 PM by wolfy » Logged
Panopeeper
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« Reply #5 on: November 23, 2007, 01:09:31 PM »
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Give us back real user controlled (and simple) MLU. "Flip",...it's up. "Flip" it's down. I'll decide when.
 
Canon, this user will trade you one facial-recognition "feature" for one real MLU anyday!

Canon was listening to you (probably much before you published what you needed).

The solution is called "live view", and you don't need to pay $8000 for it, not only the 1DsMkII, but the 1DMkIII, and even the cheapo 40D has it.

I don't have any use for the live view function on its own, but it was one of the main attractions of the 40D from my perspective. You prefocus, turn the focusing to manual and start live view. The mirror goes up and you can make several shots - and you even see, what you are shooting.

I have been using MLU all the time with the 20D, with much shorter shutter times than Ray suggests. My tests have proven, that the vibration caused by the tripod and the resonance of the camera body affect the result even in 1/several hundred sec. What I needed was bracketed exposure without camera movement in the meantime, and now I have it (the combination of live view, exposure bracketing and remote control).
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Gabor
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« Reply #6 on: November 23, 2007, 01:10:59 PM »
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"Full MLU, I suppose is what I've got on my D60, 20D and 5D. Having set the custom function to 'enable' MLU, one presses the shutter button once to flip up and lock the mirror; one waits until the vibrating tripod legs have stabilised and then presses the shutter a second time which begins the exposure. When the exposure has finished, the mirror flips back down automatically and one is ready for the next shot."
[a href=\"index.php?act=findpost&pid=155241\"][{POST_SNAPBACK}][/a]

Ray, doesn't this "1st button pressed/mirror up/ camera ready" state end with an auto shut-off after a set time lapse, as implied in my examples?
[a href=\"index.php?act=findpost&pid=155247\"][{POST_SNAPBACK}][/a]

Wolfy,
The auto timer system usually has a minimum period you can set before the shutter goes off, perhaps 5 or 10 seconds.

On all my DSLRs the first press of the shutter button flips the mirror. The second press of the shutter activates the exposure. The time delay between the first and second press of the shutter is entirely up to the user. I wasn't aware there was an automatic shut-off after the first button, but I just tried it on my 5D and you're right. It shuts off after 30 seconds, presumably to conserve battery power. I don't know if this has anything to do with the way my camera is set up. I've set it to power down after one minute of idleness.

I've never been in a situation where I've waited 30 seconds before starting the exposure. Because of the nature of subjects which are suitable for slow shutter speeds I've always been able to predict the right time within that period, but I now see that one could be unlucky waiting exactly 30 seconds for the wave to break over a rock or a flower to stop swaying in the breeze, then at the precise moment you are ready to press the shutter a second time, the mirror automatically flips down and you've missed the shot.

Is this a major concern for you?
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Wayne Fox
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« Reply #7 on: November 23, 2007, 03:55:03 PM »
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1. A programmed camera is not always an effective substitute for a thinking photographer.  This means that when a "self-timer" is controlling the moment of capture (2 sec. delay?, 10 sec. delay? 30 sec. shut-down?), any sort of peak-moment capture is reduced to a wild guess. Hardly a "professional" feature. IMO, this is no "work-around. It is a poor imitation of user-control.

[a href=\"index.php?act=findpost&pid=155217\"][{POST_SNAPBACK}][/a]


I'm  curious why MLU and self-timer seemed to be so connected?  In my Canons and Hasselblad, they are both separate functions and can be used exclusively or together at my choice.

As far as mirror lock-up and your examples, obviously when using MLU on moving subjects where capture timing is critical, I believe most would simply use a cable release to trigger the capture.  There is no connection between popping the mirror-up and taking the shot.  Yes, MLU will end in about 30 seconds, but if that's a problem, you can depress the shutter button half way to reset the cancel timer as you wait to hit the cable release.

I use both methods, depending on subject matter.

I think Michael's major complaint against Canon is the lack of a dedicated MLU button, so you can take advantage of it quickly, and even go back and forth as you are shooting.

Live View on the 40d offers a nice work around, however, I'm not sure if anyone has tested how using Live View extensively may increase heat, thus noise, with the sensor.
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wolfy
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« Reply #8 on: November 23, 2007, 08:49:54 PM »
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Panopeeper,

As far as who published what when,...I (along with many others) have been posting (and asking people such as Chuck Westfall) about this since DSLR's first appeared.

Ray,

It is not a "major" issue. Nothing about photography is life-or-death to me.    
It is a "why not?" issue, ...a discussion about design.

Like any other "feature", some will have a use for it,...some will not. For those who do, occasionally or regularly, basic, simple, user-controlled mechanical MLU has certain advantages.

We once had it.

Why has "progress" dictated that we do not have it now?

I have not seen this simple question answered anywhere.

All,

Regarding "Live-view", "self-timer" and MLU: I assume there is some reason for the 30-second shut off after the 1st press when self-timer is used.

If using the self-timer with live view, and repeatedly "half-pressing" the button during a longer-than-30 second wait, ...would we be defeating some protective limit re. heating, etc.?

I.e., would this be an "approved" use?

When using a remote(wireless) release, is there a way to half-press the shutter button via the remote? One can hardly be very "remote" if required to physically touch the camera every half-minute. Some uses of the wireless remote have to do with shooting wildlife while hidden.

The real question is  - "Why are all these questions necessary?"

It wasn't broken.

Why was it "fixed"?
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Panopeeper
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« Reply #9 on: November 23, 2007, 09:20:21 PM »
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Regarding "Live-view", "self-timer" and MLU: I assume there is some reason for the 30-second shut off after the 1st press when self-timer is used

The 40D allows for disabling auto-power off. Only the LCD will be turned off after a periode of non-usage (I don't know, how long that is).

Quote
If using the self-timer with live view, and repeatedly "half-pressing" the button during a longer-than-30 second wait, ...would we be defeating some protective limit re. heating, etc.?

There is no need to press the button again and again if auto-power off is disabled. The camera has a thermal sensor, it gives a notification if it is getting warm. From that point on the image quality may suffer (according to the manual). If it gets even warmer, the mirror closes.

Quote
When using a remote(wireless) release, is there a way to half-press the shutter button via the remote?

There are different remote controls, from Canon and from others, they differ in features. I have a cheap (compared to Canon's), no-name wired controller, it allows for half-pressing, full-pressing and locking down for longer exposures.
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Gabor
AndyF2
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« Reply #10 on: November 23, 2007, 09:54:48 PM »
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...
I also agree completely that an auto timer has serious disadvantages for MLU purposes, but it's better than nothing. All Canon's professional and prosumer cameras have full MLU. The 300D didn't and probably the 400D doesn't. I haven't checked.
...
[a href=\"index.php?act=findpost&pid=155238\"][{POST_SNAPBACK}][/a]
The 400D (XTi) has it under custom functions.  After 30 seconds, the camera will timeout and drop the mirror again.  
Andy
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Ray
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« Reply #11 on: November 23, 2007, 10:24:36 PM »
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It is not a "major" issue. Nothing about photography is life-or-death to me.   
It is a "why not?" issue, ...a discussion about design.

[a href=\"index.php?act=findpost&pid=155378\"][{POST_SNAPBACK}][/a]

Well, I can give you some 'why not' answers, Wolfy. Modern cameras are battery operated. Are you asking for a hybrid camera that has some completely mechanical functions such as a button that flips up the mirror and keeps it there whether the camera is powered up or not?

Do you not realise that Canon has good reasons (perhaps even an obligation) for not confusing most of its customers who may not be geeks or photography enthusiasts. Some buyers of DSLRs just want a good camera with a good reputation even if they know little about photography.

What would happen if there were a button on the back of the camera that was entirely mechanical and pressing it flipped up the mirror permanently until it was pressed again? Do you not think there'd be a few trips back to the store from naive customers complaining they couldn't see through the viewfinder?  

Alternatively, which would you prefer, the possibility of forgetting that the mirror was flipped up in battery mode and an hour later getting a flat battery, or the certainty of never missing a shot that coincided with the automatic flip down of the mirror after 30 seconds, perhaps a one in a thousand chance?

I've never used a wirelss remote control but I'd think it poor design if it didn't have a means of half pressing the shutter, an action which is necessary for autoexposure.
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AndyF2
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« Reply #12 on: November 23, 2007, 10:40:46 PM »
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...
2. Opinions differ as to MLU usefulness at any given shutter speed. However, anytime there is a POTENTIAL benefit from MLU, there is no arguing this fact:
Reduced or "damped" mirror vibration is not the same thing as ELIMINATED mirror vibration. Canon's providing real MLU would "admit" nothing except this incontrovertible fact. [ As to the nebulosity of MLU usefulness -- For an in-depth study of MLU effectiveness under  various conditions, timings, focal-lengths, etc. done by a serious, careful and skilled photographer, see first link below.]
...
Fritz Polking index (See Workshop I - "Sharp Photographs"): http://www.poelking.com/index_e.htm
...
[{POST_SNAPBACK}][/a]
A timely topic; there is an excellent article on this in the Nov/Dec issue of Photo Techniques magazine [a href=\"http://www.phototechmag.com/]http://www.phototechmag.com/[/url]

Timothy Edberg http://www.edbergphoto.com/ measured the effect of mirror slap on sharpness.  He mounted various cameras (FA, AE-1, F4, 8008S) with various lenses on 3 different tripods and heads, photographed a standard resolution test chart, and compared the maximum resolution for the lenses and shutter speeds.
My summary of his results (lots of charts in the article):
- for lenses 200 mm or longer, mounted on a tripod, there is a "Valley of Death" starting at 1/125 and extending to 1/2 sec, with the worst point around 1/30, where up to 70% of your resolution will be lost.
- a 100 mm lens loses up to 30% in these conditions.
- tripod leg length has no effect, min or max extension.  However an extended center column will ruin you; resolution starts being lost at 1/125, 70% resolution is lost at 1/15 and it shows little sign of recovery until 2 seconds.

Some variables not experimented with in his article that would be worth exploring are the effect of image stabilization, and more modern cameras that may have less mirror slap and better dampening.  Also not mentioned, is the tripod mount: with the 200 mm lens, was the camera on the tripod, or was the lens on the tripod and the camera hanging on the lens.

It will be quite ironic if a handheld 200-400mm shot with modern IS has less resolution loss than than a tripod mounted shot without mirror lockup!

Andy
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Ray
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« Reply #13 on: November 24, 2007, 09:17:26 AM »
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A timely topic; there is an excellent article on this in the Nov/Dec issue of Photo Techniques magazine http://www.phototechmag.com/

Timothy Edberg http://www.edbergphoto.com/ measured the effect of mirror slap on sharpness.  He mounted various cameras (FA, AE-1, F4, 8008S) with various lenses on 3 different tripods and heads, photographed a standard resolution test chart, and compared the maximum resolution for the lenses and shutter speeds.
My summary of his results (lots of charts in the article):
- for lenses 200 mm or longer, mounted on a tripod, there is a "Valley of Death" starting at 1/125 and extending to 1/2 sec, with the worst point around 1/30, where up to 70% of your resolution will be lost.
- a 100 mm lens loses up to 30% in these conditions.
- tripod leg length has no effect, min or max extension.  However an extended center column will ruin you; resolution starts being lost at 1/125, 70% resolution is lost at 1/15 and it shows little sign of recovery until 2 seconds.

Some variables not experimented with in his article that would be worth exploring are the effect of image stabilization, and more modern cameras that may have less mirror slap and better dampening.  Also not mentioned, is the tripod mount: with the 200 mm lens, was the camera on the tripod, or was the lens on the tripod and the camera hanging on the lens.

It will be quite ironic if a handheld 200-400mm shot with modern IS has less resolution loss than than a tripod mounted shot without mirror lockup!

Andy
[a href=\"index.php?act=findpost&pid=155401\"][{POST_SNAPBACK}][/a]

Andy,
This is something worth looking into. Telephotos lenses I think might be particularly vulnerable to the effects of mirror slap because they can be so precariously balanced on a single tripod and any movement during exposure is magnified in the image. I've had my 100-400 on a tripod, attached by the collar, and seen quite obvious wobbling as a result of the mirror slap and shutter release. I recall on a number of occasions looking through the viewfinder as I pressed the shutter with remote cord and noticing pronounced image shimmer immediately afterwards.

A reasonably fast shutter speed will beat that shimmer, however. Determining just how fast will depend on a lot of variables, I'm convinced.

Nevertheless, whenever I've attempted some comparisons, whatever the lens, I've never noticed any significant loss of resolution at any shutter speed, without MLU, although a certain very narrow range of shutter speeds did cause problems as I recall.

I'm pondering the reason for this. What camera did I use on those occasions. I'm convinced the 20D has very good mirror dampening. Many people complain about the noise of the shutter, the fact that it will scare away any wildlife. But this noise is there for a reason. I can't believe Canon technicians and scientists, having designed such a ground breaking camera with regard to image noise, would not be aware of the noisy shutter. Do you think they would say, 'Oh! Too bad! But who cares!'

It is a fact that vibrations that cause mechanical problems, causing things to rattle etc, are not audible. It's only the side effects that are audible. When you go to a rock concert and the bass is so deep and loud and strong it almost seems to interfere with your heart beat, those frequencies are not actually heard. They're frequencies below the audible threshold. The sounds you actually hear are much higher, around 20-30Hz. The frequencies that cause physical vibrations are below that; around 5-15HZ, completely inaudible.

Well, what's that got to do with the 20D? It is my 'hunch' shall we say, that Canon have attempted to convert the harmful low frequency mirror slap vibrations that blur image detail at low shutter speeds (on a tripod) to harmless higher frequency noise which has no effect on the image.

I mentioned this some years ago but no-one took it up. In view of this resurgence of interest in MLU, I decided today to give my 20D a test on my rather inadequate tripod, a Manfrotto 714SHB which I use when I travel.

This tripod is very light, weighing just 2.2Lbs or about 1Kg and very compact. It is recommended for a maximum load of 5.5lbs and is described as being suitable for digicams. If mirror slap is going to have an effect, then this is the tripod that will reveal it, (or do you think my logic is flawed?)

Okay! Without further ado, the results and conclusions. On the Manfrotto 714SHB tripod designed for P&S cameras, the 20D with 50/1.8 lens performs flawlessly from 1/80th sec to 1/3rd sec.

Whether mirror is locked up or not makes not the slightest difference of any importance.

In true pixel-peeping fashion I have provided 200% crops below at maixumum quality jpeg compression. I don't expect people to accept my word for these results. Here they are.

[attachment=4002:attachment]  [attachment=4003:attachment]  [attachment=4004:attachment]  [attachment=4005:attachment]  [attachment=4006:attachment]
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Ray
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« Reply #14 on: November 24, 2007, 10:25:11 AM »
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I should mention in case anyone thinks I'm advertsing tripods, that I use a Really Right Stuff L Bracket and Clamp. The bracket is attached to the camera and the clamp to the, in this case, ball head tripod. This means that, whether the camera is positioned horizontally or vertically, it's centrally located immediately above the ball head. This allows for greater stability, especially if the camera is vertical.

I wouldn't like to think that people will rush out and buy a Manfrotto 714SHB because it has some magical properties of counteracting the effects of mirror slap.  
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wolfy
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« Reply #15 on: November 24, 2007, 11:59:23 AM »
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Thanks to all for input and answers to some questions.

A brief sub-totaling of test-results:  

Let's be generous and assume equal expertise/thoroughness among our three testers, Polking, Edberg, and Ray. (Whatsamatta you guys? No one has acknowledged actually reading Polking's work.)

The results end in argument.

Polking and Edberg say image quality can often be lost to mirror-slap vibration.

Ray says his test shows no ill-effect of any importance.

What to think?

Here is what I (still) think:

It is inarguable that a mirror which does not move will not cause image-quality loss due to vibration. Thus one possible negative has been eliminated from the IQ equation, freeing us to concern ourselves with the other elements.

Works for me.

Canon, please give us back simple, completely user-controlled mechanical( no battery drain) MLU.

Quote
Well, I can give you some 'why not' answers, Wolfy. Modern cameras are battery operated. Are you asking for a hybrid camera that has some completely mechanical functions such as a button that flips up the mirror and keeps it there whether the camera is powered up or not?

Do you not realise that Canon has good reasons (perhaps even an obligation) for not confusing most of its customers who may not be geeks or photography enthusiasts. Some buyers of DSLRs just want a good camera with a good reputation even if they know little about photography.

What would happen if there were a button on the back of the camera that was entirely mechanical and pressing it flipped up the mirror permanently until it was pressed again? Do you not think there'd be a few trips back to the store from naive customers complaining they couldn't see through the viewfinder?    [a href=\"index.php?act=findpost&pid=155399\"][{POST_SNAPBACK}][/a]

Anyone too dumb to equate a black viewfinder with a locked-up mirror should have his camera confiscated and his "reasonably intelligent human" license revoked. (Let us remember that it is by looking in the viewfinder that a user is advised of any number of "settings" he has "forgotten" that he chose.)

I refuse to be reduced to the "flat battery vs. missed shot" choice between two evils, as I have, by the simple expedient of accepting some responsibility, eliminated the need, when I chose the mechanical MLU. (...which Canon will undoubtedly offer after reading this discussion.)  

Thanks, everyone, for the responses re. the Live-view/MLU use. It is good to learn that the auto shut-off can be disabled, eliminating button-press repeating. Also that the wireless remote has half-press capability when needed.

Another question, please (main interest 1DIII); Speaking of the second button-press when using live view, how instantaneous is the release? Is there noticeable "lag"?

'Nother 2-in-1  question-
1. Same question (lag?) without live-view, but still using self-timer -
2. Do I correctly understand that the "self" timer offers 3 MLU choices/ some few seconds, then 10-or-so, then "User" chosen  release until 30 second auto-shutdown (or unlimited if shut-down disabled)?

Re magnified live-view for focusing - can the focus be thus set, then Live-View exited with focus remaining as-set, for a battery-saving "wait" using only the self-or-user timed MLU? I will be watching through binoculars,  remote in hand, awaiting "the moment".

Are we havin' fun yet?
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Ray
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« Reply #16 on: November 24, 2007, 12:17:07 PM »
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Canon, please give us back simple, completely user-controlled mechanical( no battery drain) MLU.
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Canon, please continue with the 20D concept of transferring the lower frequency vibrations into higher frequency sound, but introduce a phase shift counteracting sound to silence the effect. Then we'll have a silent shutter and no need of MLU.  
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wolfy
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« Reply #17 on: November 24, 2007, 03:15:50 PM »
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Canon, please continue with the 20D concept of transferring the lower frequency vibrations into higher frequency sound, but introduce a phase shift counteracting sound to silence the effect. Then we'll have a silent shutter and no need of MLU. 
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Can your please beat up my please?

A bird in the hand beats 2 pies in the sky.

My please gets already proven vibe-free shooting. It's a  done-before and doable-again deal.

Your please gets reported(no offense, but more complete testing at the "pro-camera " level is needed) vibeless operation + theoretical shutter silence.

How about combining pleases, ...a proven and a hypothesized?

Mechanical MLU for no-vibes, and effectively counteracted shutter-only sound. Ahhh, ...steady silence!  

Any "lag time" answers, anyone?  
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wolfy
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« Reply #18 on: November 24, 2007, 05:00:55 PM »
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Telephotos lenses I think might be particularly vulnerable to the effects of mirror slap because they can be so precariously balanced on a single tripod and any movement during exposure is magnified in the image.
 ...

A reasonably fast shutter speed will beat that shimmer, however. Determining just how fast will depend on a lot of variables, I'm convinced.

Nevertheless, whenever I've attempted some comparisons, whatever the lens, I've never noticed any significant loss of resolution at any shutter speed, without MLU, although a certain very narrow range of shutter speeds did cause problems as I recall.

...

It is my 'hunch' shall we say, that Canon have attempted to convert the harmful low frequency mirror slap vibrations that blur image detail at low shutter speeds (on a tripod) to harmless higher frequency noise which has no effect on the image.

...

 In view of this resurgence of interest in MLU, I decided today to give my 20D a test on my rather inadequate tripod, a Manfrotto 714SHB which I use when I travel.

This tripod is very light, weighing just 2.2Lbs or about 1Kg and very compact. It is recommended for a maximum load of 5.5lbs and is described as being suitable for digicams. If mirror slap is going to have an effect, then this is the tripod that will reveal it, (or do you think my logic is flawed?)

Okay! Without further ado, the results and conclusions. On the Manfrotto 714SHB tripod designed for P&S cameras, the 20D with 50/1.8 lens performs flawlessly from 1/80th sec to 1/3rd sec.

Whether mirror is locked up or not makes not the slightest difference of any importance.

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Can't say much about any hunch,...since they are always concrete, definite "maybe"'s.

But about MLU testing:

You touch on the significant element in your first paragraph above. [Sidebar - Polking addresses the use of multiple supports for tele shots in one or more of the several articles at his web-site.] The reason I specified a long-tele in my first post (although I might have said "macro") is that these are the uses where mirror (or any other) vibration is most harmful. A 50mm lens does not make an effective test-substitute.

In-plane vibration (up/down, right/left,..."shift") gives a blur over the whole image that is the same, proportionally as the movement of the sensor.(A 1/100 sensor movement gives a 1/100 image/print blur.)

Angular vibration can be many times worse.
Any angular movement caused by vibration at-the-camera covers (blurs) a great deal more territory at a distant (or highly magnified )target.  Vibrational rotation that blurs 1 inch of a subject at 10 yards will blur 10 inches of the subject at 100 yards.

Reduce the mag or the distance, ...you have reduced the blurring effect of the vibration.

Quite possibly to the point where a given photographer might decide there was no difference of any importance.

If a test procedure is such that differences are minimised,... differences will be , Um, ...minimal.

Consider an image taken with a 50mm at a given desired shutter-speed, at say 10 feet. Lets say there are whiskers on the target. Let's also say that the camera's mirror action vibrates(angularly) the image at-the-target one-quarter whisker's worth.  Many might not notice, ...it still looks like a whisker, huh(?), only a whisker 25% thicker. (100% whisker plus 25% motion blur.)

Now take the same photo, same desired shutter-speed, using a 1000mm, at 200 feet. The same amount of camera motion will give a 5-whisker blur.  Many viewers will think that whiskers 6 times as thick (100% whisker plus 500% blur)no longer look like whiskers at all,..but sticks(or whatever.)

Now remember that the effect is seen throughout the image, not only effecting the whiskers.

We are beginning to describe something a bit less than optimum image quality.  

Mirror vibration "tests" which leave out distance-to-target (or magnification)considerations are missing a great deal of "the point".

Being forced into attempts to minimize the effect by going to a faster-than-desired shutter speed means that the camera's limitations, not the photographer, are dictating the technique and the end result. (I want THIS much motion-softness in my wave,...but the camera says I have to have only THAT much, or my rocks will be blurry.)

Ok, You've got me curious - if you "never" noticed significant res. loss, etc., at any shutter speed, ...then what were the problems, at some shutter speeds, that you "recall" in the same sentence above(3rd quoted paragraph.)?  Is this one of those "Can both these statements be true?" tests?


Disclaimer:  I am interested in this subject, and enjoying this exchange. Nits are picked in a spirit of playful sharp-shooting. If anyone is not having a good time, just let me know, and I will kill myself.      (....or something.   )

Correction welcome,
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Ray
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« Reply #19 on: November 25, 2007, 11:50:03 PM »
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Angular vibration can be many times worse.
Any angular movement caused by vibration at-the-camera covers (blurs) a great deal more territory at a distant (or highly magnified )target.  Vibrational rotation that blurs 1 inch of a subject at 10 yards will blur 10 inches of the subject at 100 yards.

Reduce the mag or the distance, ...you have reduced the blurring effect of the vibration.

Quite possibly to the point where a given photographer might decide there was no difference of any importance.

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Wolfy,
The above might be quite true in principle but I believe there are so many other contributing factors that allow the blurring without MLU to be a problem, there can be no hard and fast rule except, when in doubt use MLU.

Although I'm carrying my 100-400 zoom with me on this trip, I wouldn't waste my time using it on this ultra-lightweight 714SHB. However, I did run through the same test on this tripod with my 5D using the same 50/1.8 lens; same target from the same distance.

Surprise! Surprise! The 5D shows a mirror slap problem around 1/30th second exposure, but only around 1/30th. At 1/15th it's gone and at 1/60th it's gone. It's also not evident at any shutter speed slower than 1/15th.

So here we have two different cameras that show different results with regard to mirror slap, both using the same lens, same tripod and same target from the same distance. The 20D is free of any problems. The 5D shows obvious blurring at 1/30th.

Hhmm! I think I can now say I've contributed something definite to the sum total of scientific knowledge. How gratifying   .

By the way, shortly after getting my 20D some years ago, I vaguely recall comparing its resolution with my old D60 using the 100-400 on a sturdy tripod.

It was late in the afternoon. I recall I'd taken the D60 shots first, then switched bodies. At some point with the fading light, I realised I was shooting at slow shutter speeds within the danger range without MLU. So I turned on MLU quickly (terribly difficult and awkward with all those dials and buttons   ) and repeated the shots.

When examining the shots later on the computer monitor, I expected to see noticeable blurring in the shots at the slow shutter speeds without MLU activated.

I remeber being rather puzzled by the fact I could not really see any difference of any consequence at ridiculously high magnification. I should have pursued the matter at the time but the fact is I don't use my 100-400 much on a tripod and I was excited by the fact that, with the low noise of the 20D, I had even less reason to use a tripod with this lens. Comparing the 20D with the D60 was like having a 100-400/2.8 instead of f5.6 lens (except for the DoF implications of f2.Cool.
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