Does "no mirror" really = sharper negs?

[2F/2F]

Here's a thought experiment: Use a 10 second exposure and move the camera up and down? Will the dot be blurred? Of course; it will be a line. Now explain why the physics of motion are different for 10 seconds vs. 1/10th of a second.

Yes, the dot moves with the camera. That's the point. However the background doesn't move and the path the dot traces on the background will be recorded.

The point of the test should be to see how a moving camera records a static object in a real world situation...not to see how a moving camera records the movement of an object that is moving just as much as the camera. Photographing the laser attached to the camera will tell you how much the camera moves, but photographing a still object will tell you how a still object will actually be rendered. The first is simply informative. The second gives you actual practical knowledge. For instance, not just how much does the camera move, but how much movement is acceptable in a picture that is shot in a real-world situation.

Really. This is test is terribly over engineered. Why can't you just shoot the front page of the Times tacked to a bulletin board? Shooting a laser is just a techy way to make some piece of modern technology seem more useful than it really is.

...besides, we all know that the ONLY real use for a laser pointer is for playing with cats.

 

[bdial]

..besides, we all know that the ONLY real use for a laser pointer is for playing with cats.

That's about the best use I can think of for one.

Really. This is test is terribly over engineered. Why can't you just shoot the front page of the Times tacked to a bulletin board? Shooting a laser is just a techy way to make some piece of modern technology seem more useful than it really is.

Maybe because the techie geeks among us are more likely to have a laser pointer than any page of the Times?
Besides, everyone knows a test using technology is far superior to those that don't.:rolleyes:

 

[2F/2F]

That's about the best use I can think of for one.

Yup...and we don't even have to get off of our fat asses to do it! Even better!

Call me a Luddite, but I buy the paper every week day. $16 per month to support analog circulation (and the local American jobs that go with it) in my local newspaper machines is worth it to me. I get way more information than I would online, in less time. I also get the funnies, the crossword, sudoku, and one of my personal favorites, the obits. Plus I get to take a walk to the machine from work and back. I also don't bug my eyes out or have to sit on my butt to do it. I feel I am lucky to work in a place without a computer or ass sitting on being a necessary part of my job, personally.

(Any sheet of paper with text on it will do, of course.)

 

[Lee L]

http://xkcd.com/675/

 

[BetterSense]

Here's a thought experiment: Use a 10 second exposure and move the camera up and down? Will the dot be blurred?

No, it will not be blurred, unless the laser pointer is poorly attached and moves in relation to the camera. Laser pointers do not leave trails on the wall; it just looks like they do. Why don't you try it some time and report back.

 

[Roger Krueger]

Of course mirror vibration exists. Although the areas where it's the most vexing (high magnifications, long telephotos) are situations you can't really use a rangefinder anyway.

In addition to all the other problems, the order of magnitude is completely off in the laser/penny tests. How much effective (subject space) movement would you need to make newsprint unsharp? 0.25mm maybe? Can you really see an instantaneous movement that small in a fuzzy consumer laser spot? Now translate that to an amount of actual camera movement. Do you really think the penny test is going to show that?

For handheld shooting at critical speeds I found getting away from the human movement caused by the button press (by using a self timer, a cable release in the other hand, or burst mode on one of Satan's little toys) more important than camera mechanics.

Although sure, past that point, my Hi-Matic and Mamiya Universal completely smoked my XD-11 at similar critical speeds/angles of view. My DSLR kept up a little better because of burst mode—out of eight shots there'd usually be one or two where human shake and mirror shake mostly canceled out and gave me something decently sharp. The other 6-7 were often even worse than the XD-11, not that it really matters.

 

[maderik]

No, it will not be blurred, unless the laser pointer is poorly attached and moves in relation to the camera. Laser pointers do not leave trails on the wall; it just looks like they do. Why don't you try it some time and report back.

What, your walls aren't covered in slow decay phosphors? Sigh, I guess I get what I deserve when I attempt thought experiments under the influence of cold medicine. Still cameras do not have persistence of vision like cathode ray tubes or the human eye so I was totally off-base.

 

[BetterSense]

In your defense, the laser spot can blur even if the laser pointer is attached firmly to the camera, because the laser pointer is probably not oriented exactly along the axis of the lens, and thus there will be a small amount of blur from parallax effect if the wall moves closer and farther to the wall during the course of the wiggling.

 

[JBrunner]

This stuff is really funny, the bits about laser pointers and pennies. In order for a test to provide any meaningful information there needs to be a context, and "speermints" like these don't really have one. Camera design, exposure time and focal length all play important roles in how a mirror slap will affect sharpness. One combination may yield on result, and a different combination another. You control what you can. When sharpness is critical and the subject allows I use MLU, because it can't hurt, and sometimes it makes a difference, and sometimes not. When it isn't practical I use a better shutter speed if I can, or I takes my chances. In regard to the range finder vs SLR thing, you use the tool that is appropriate. In all my professional life I personally have never chosen to use a rangefinder based on shutter vibration, although the situation might arise where I might. When I have chosen to use a rangefinder it has always been a matter of ergonomics, optics, and noise. MLU is simply a feature on some SLR's that can be used when appropriate, nothing more and nothing less.

 

[Sirius Glass]

This stuff is really funny, the bits about laser pointers and pennies. In order for a test to provide any meaningful information there needs to be a context, and "speermints" like these don't really have one. Camera design, exposure time and focal length all play important roles in how a mirror slap will affect sharpness. One combination may yield on result, and a different combination another. You control what you can. When sharpness is critical and the subject allows I use MLU, because it can't hurt, and sometimes it makes a difference, and sometimes not. When it isn't practical I use a better shutter speed if I can, or I takes my chances. In regard to the range finder vs SLR thing, you use the tool that is appropriate. In all my professional life I personally have never chosen to use a rangefinder based on shutter vibration, although the situation might arise where I might. When I have chosen to use a rangefinder it has always been a matter of ergonomics, optics, and noise. MLU is simply a feature on some SLR's that can be used when appropriate, nothing more and nothing less.

The bottom line is what I said may posts ago. Mirror bounce is not a factor for speeds shorter than 1/[focal length]. For longer shutter speeds use a tripod and if you think it is necessary the MLU. Since then this thread has been a great waste of internet bandwidth and time.

Steve

 

[zumbido]

The bottom line is what I said may posts ago. Mirror bounce is not a factor for speeds shorter than 1/[focal length]. For longer shutter speeds use a tripod and if you think it is necessary the MLU. Since then this thread has been a great waste of internet bandwidth and time.

Steve

And I'll note again that many published experiments have shown this statement to be inaccurate.

 

[JBrunner]

And I'll note again that many published experiments have shown this statement to be inaccurate.

They don't show a thing except in regards to a specific camera/focal length/exposure time/focus. That's the real point. Sometimes it matters, sometimes it doesn't. There are so many variables involved with this subject that absolutes have no validity. The only absolute is what you wind up with after the fact using all the tools to the best of your ability within the parameters of a specific situation. All of the debates and experiments involve an involuntary subjectivity because of the inescapable nature of photographic possibilities, and that isn't a very solid place to stand. If someone made a test with the exact camera, lens, focal length, and exposure, and had the same idea as me as to what constituted sharpness, I'd pay attention. Other than that, it's a TV in another room.

Rather than "does it make a difference?", which of course it can, the question should be "in what situations might it make a difference, and if so, how much?"

 

[Sirius Glass]

They don't show a thing except in regards to a specific camera/focal length/exposure time/focus. That's the real point. Sometimes it matters, sometimes it doesn't. There are so many variables involved with this subject that absolutes have no validity. The only absolute is what you wind up with after the fact using all the tools to the best of your ability within the parameters of a specific situation. All of the debates and experiments involve an involuntary subjectivity because of the inescapable nature of photographic possibilities, and that isn't a very solid place to stand. If someone made a test with the exact camera, lens, focal length, and exposure, and had the same idea as me as to what constituted sharpness, I'd pay attention. Other than that, it's a TV in another room.

Rather than "does it make a difference?", which of course it can, the question should be "in what situations might it make a difference, and if so, how much?"

I am glad that someone get it.

Steve

 

[2F/2F]

Laser pointers do not leave trails on the wall; it just looks like they do.

Considering that the dot from a laser pointer is something that the film sees during exposure, then what something "looks like" to the film is exactly what will be recorded. Of course it is not left on the wall. We all know that. It is just a ray of light, not a ray gun beam that marks the wall. However, if the shutter is open, and the aperture is such that you can properly expose the dot on the wall, there will be a streak in the picture.

The point I am making is that the streak is not very informative. It tells you how much movement there is, but does not tell you how much movement is acceptable.

 

[Xmas]

Hi

The reason why people use rfdrs, like M2, Canon P or Retina IIIs for street shooting is

shutter lag - milliseconds
shutter noise - in a noisy street - unobtrusive

Many SLR's e.g. OM1 wont have much mirror bounce until the return stroke when the picture is in the can but will still be noisy and have more delay.

Note with the OM1 you can inhibit the mirror.

In HCB's day the Nikon F was not available and SLR were not really used by PJ.

It is possible to tolerate the delay of a Contax G1 or G2, and the lenses are excellent, but it is difficult to justify.

Noel

 

[keithwms]

Let me just approach this in a slightly different way.

Those of you who say MLU doesn't matter, are you saying that it's a worthless gimmick perpetrated upon us by the cameramakers? So, they all got together and said, let's sock it to those poor bastards and add on a feature that they really don't need...

And if you support this hypothesis, I ask: how much extra profit do you suppose it enabled them to reap from these bodies with the worthless MLU?

Or did they do it not for profit but simply for sh*ts and grins? I'd find that hard to believe; the modern [film] camera, to me, is one of the most purposefully designed tools I can imagine. It really wasn't until the digital generation that we started to see all kinds of nonsense shoved in the box just to make people feel like they were getting more for their money.

This all reminds me of the lovely quote by Marx. No, not that Marx, the Marx most people still respect, Groucho Marx:

Well, Art is Art, isn't it? Still, on the other hand, water is water. And east is east and west is west and if you take cranberries and stew them like applesauce they taste much more like prunes than rhubarb does. Now you tell me what you know.

 

[Xmas]

Those of you who say MLU doesn't matter, are you saying that it's a worthless gimmick perpetrated upon us by the cameramakers?

[/I]

MLU was necessary for non retro focus wide angle lenses, they wanted to sell system cameras, to bury the rangefinders like Contax IIa and Leica M2, which could accept non retrofocus lenses.

It was also useful for low vibration shots of star fields etc.

MLU is not so fashionable today...

Noel

 

[zumbido]

They don't show a thing except in regards to a specific camera/focal length/exposure time/focus. That's the real point. Sometimes it matters, sometimes it doesn't.

Of course, which is what I said earlier. Just refuting the blanket assertion that it is a "myth" or it never matters, which is what some are saying.

 

[markbarendt]

MLU is not so fashionable today...

Well neither am I, but my employer still seems to find me important enough to use me regularly.

Seriously though, my employer likes my work because I use and don't short cut the best processes. This means they have less to worry about; the machines will start on the first try, run reliably, and everybody gets home safe.

MLU is one part of a regimen of best practices for getting sharp pictures and it costs next to nothing in money or time to use it.

To me it seems truly silly to put all the effort needed to carrying, setting up, and throwing a camera on a tripod just to ignore using the MLU which takes all of 5 extra seconds to use.

 

[Xmas]

Yes but you can get nearly the same effect (now days with inverted telephotos) with a SLR on self timer which fires the mirror early, you still get a delay, but the vibration will be less.

Some of the earlier SLR you lose a frame resetting the mirror?

As I read it the OP was about street shooting not star fields and the like. Maybe I'm wrong again.

When I take night shots I may fire the shutter with a black felt table tennis bat obscuring the field of view as even a leicia fabric shutter has an impulse on blind movement,and my tripods are not that heavy to necessarily absorb.

Noel

 

[benjiboy]

Please correct me if you think I'm wrong, but I have always thought that in an SLR in short exposure say 30th to 1000th sec. by the time the mirror reaches the top of its travel and hits the foam bumper the picture has already been taken.

 

[markbarendt]

Please correct me if you think I'm wrong, but I have always thought that in an SLR in short exposure say 30th to 1000th sec. by the time the mirror reaches the top of its travel and hits the foam bumper the picture has already been taken.

First, the mirror has to be completely out of the way or it will be in the picture so I doubt that the shutter fires until it's up all the way. This is part of why a rangefinder can fire faster, there is no mirror to wait for.

Second, there are two impulses "felt" by the camera. First the acceleration of the mirror upward from it's resting position and then the mirror being stopped. Even if your thought was true, the initial acceleration would be affecting the camera before the shutter fired.

 

[Bill Harrison]

MLU

"Edge of Darkness", Barry Thornton. Chapter 5, pg 65. Hand held , Light tripod, Heavy tripod and Heavy tripod with mirror up, from 1 sec to 1/125th. Pretty definitive. But so what, first get the picture.... then whine about the blur, IF it's there... Mirrors are obviously the least important cause of loss of sharpness.

 

[ruilourosa]

hello

i wonder why this thread has gone so long and for so long, the answer is simple: test the cameras!

put some film in a camera, any fine grain should do

get a small led light and put it really far

wait for the night

and: shoot at different speeds, with and without mlu at a constant f stop

you can also test your hand steadyness and your tripod steadyness

take notes

develop normally

enlarge the white dots

the things more close to a dot are the best for you


i´ve seen tripods worse than my hands...



i really think that mirrorless cameras are great: small, usually quiet, and with the hability to hold short focals without the retrofocus design, i think that is a great advantage, just compare a wide angle like the biogon or similar design (there are a few) and a retrofocal counterpart distagon curtagon or flektogon or any slr wideangle, you should note differences in geometrical aberrations, resistance to flare, and resolution in the corners.

but as with everything: you should get along with your camera... it´s a tool but if it doesn´t work with you it´s a problem...

i get along with most of my cameras but some work better for me, spotmatic, nikon f2, minox, even hasselblad 501, others are a bit strange and i use them more often, or more in a need basis like fuji rangefinder or the bronica s2


well good luck taking pictures, and if the camera you use does not work with you try a different one, mirrors apart, she (the camera) should be your perfect picture taking bitch

 

[markbarendt]

Yes but you can get nearly the same effect

The real questions we need to ask is "how important is having this photo sharp?" and "what are my odds of getting a sharp photo in this situation?"

If the odds are against you and sharp is truly important, you need to decide if "nearly the same" is good enough.

Some of the earlier SLR you lose a frame resetting the mirror?

Just the cost of doing business.

As I read it the OP was about street shooting not star fields and the like. Maybe I'm wrong again.

When I take night shots I may fire the shutter with a black felt table tennis bat obscuring the field of view as even a leicia fabric shutter has an impulse on blind movement,and my tripods are not that heavy to necessarily absorb.

Noel

Good idea with the paddle.

Yes the OP asked about street shooting but the thread veered some.

MLU would be problematic in fast hand-held work but the same questions I asked above apply. Controlling the mirrors effect or eliminating it altogether are important considerations.

When I have to have sharp photos I don't slow the shutter under about 4x focal length until I pull out a mono-pod or tripod or strobe.

Actually my mono-pod is under my small cameras even in broad daylight for anything important.