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03-03-2012, 02:12 AM   #31
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Are the car pictures full images or crops?

Another thought, since the shutters actually take 1/180 ( or perhaps slightly faster) to travel over the sensor and the picture is sort of painted from up to down (or if its down to up) when using a shorter shutter time. What if an object where to travel in the same direction as the picture is painted on the sensor? The object would appear to be longer then it really is, and if it traveled in the opposite direction it would appear shorter.

The camera wasn't by any chance tilted in portrait orientation?

03-03-2012, 02:52 AM   #32
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QuoteOriginally posted by JinDesu Quote
We still have mechanical shutters. You can hear it, shoot the camera on 2s timer or 3s remote and you'll hear the mirror lock up on button press, followed by the shutter. And yes, strobe photography (and how flash freezes images) is associated with the speed of the flash image and the maximum shutter speed defines the speed at which the shutter will remain fully open at the time of the flash.

Higher end models of DSLRs will have faster sync speeds because they shutter mechanisms are better.
However not relevant for this interesting thread, a simple conclusion is that when the camera is put in sensor cleaning mode it opens the shutter? And if you open up the K-01 or any digital cam to change lenses, the shutter plane is exposed and not the sensor? Hmmm, quite a relief so to speak...

@Ron: there is a difference between your well done exposures and the examples with the cars, that being that you probably held your camera steady, right?
03-03-2012, 02:57 AM   #33
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Hmm, one thing that stands out to me is the horizion in those pics is out, Just wondering, Do you have auto horizion correction "On"??? Do you remember when you took the pics, id you have the horizion straight??? There may infact be something wrong with the mechanics of the SR/Horizion correction on one side of your sensor it may have failed, that would cause an Incorrect horizion level, and because the same elements are at work with SR, only one side of the sensor would have been trying to adjust for SR in your original blurred image, and as Gimbal said, there also seems to be a slur in the image downwards on the right, again, maybe pointing to the right hand side of the sensor shake/horizion correction motors not operating correctly

Not completely positive of this, just throwing out ideas based on what you are experiencing and what we are all seeing.

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03-03-2012, 02:58 AM   #34
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Oh!!!! And a big Thank-you Ron, those pictures show ........... Sorry I lost my train of thought..

03-03-2012, 05:15 PM - 1 Like   #35
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QuoteOriginally posted by NeatKnight Quote
Here's another example.
Image A was shot at 1/6000.
Image B was shot at the same time at 1/160 (more than 5 stops brighter!)
Image C is simply image B pulled 4 stops darker in LightRoom. It should be brighter than image A.
So it looks like either:
(a) There's reciprocity failure at high shutter speeds
(b) Camera increases the ISO without permission at high shutter speeds
or (C) The shutter just isn't moving at the nominal speed
There is maybe something wrong. You can test that. Set op your camera on a tripod with SR off. Make the light to be good, since you want to know if your shutter is working the way you want it. When you toss a marble over the table or spin a coin round on it's side you should be able to see the difference between 1/160th and say 1/1000th. For a fast spin maybe even 1/2500 would make a difference.

QuoteOriginally posted by Twarp Quote
@Ron: there is a difference between your well done exposures and the examples with the cars, that being that you probably held your camera steady, right?
Yes that is true, I was aiming for good pictures whereby I was aiming at a small DOF in bright sunlight without any ND filter in my camerabag.

QuoteOriginally posted by cmohr Quote
Oh!!!! And a big Thank-you Ron, those pictures show ........... Sorry I lost my train of thought..
Well then the picture turend out very good
03-03-2012, 05:44 PM   #36
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Why would you shoot 1/6000 in poor light, those cars are not going that fast. F2.8 is a recipe for a failure in those conditions with the narrow DOF.
fence and the loudspeaker are in focus the car is not.
Crank up the ISO, close down aperture some and play with shutter speeds that are within reason. Then run the images through Topaz De-noise.

p.s. why would anyone shoot a lands-scape at 1/6000?. Unless of course, you want to explore the limits of the system to find out where it just can`t bail out the operator.

Last edited by Ex Finn.; 03-03-2012 at 06:04 PM.
03-03-2012, 06:22 PM   #37
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QuoteOriginally posted by NeatKnight Quote
Here's another example.
Image A was shot at 1/6000.
Image B was shot at the same time at 1/160 (more than 5 stops brighter!)
Image C is simply image B pulled 4 stops darker in LightRoom. It should be brighter than image A.
So it looks like either:
(a) There's reciprocity failure at high shutter speeds
(b) Camera increases the ISO without permission at high shutter speeds
or (C) The shutter just isn't moving at the nominal speed
How can you come to that conclusion?
Obviously image B is not 5 stops brighter than A. Anyone can see that. The foreground is actually darker. So either the light changed (and just from how the light render, it appears to have done so), and/or you changed the aperture when you changed the shutter time (which the camera will do itself unless you shoot on manual setting).
And C...well given that A and B looks fairly equally exposed, within half a stop or so, of course C will be bloody dark when you pull down the light 4 stops!

Don't take this the wrong way, but I get the feeling you need to read up on the basics of photography. Without understanding how light, iso, shutter speed, and aperture work together, you can't understand anything the camera do.
03-03-2012, 06:48 PM   #38
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QuoteOriginally posted by NeatKnight Quote
Here's another one.
I was using a K 105mm prime, wide open at f2.8. The light was better than I expected. I wasn't trying to pan at this speed, I didn't think it was necessary or possible.
The fact that the fence and pole etc are also heavily blurred, shows this is user and not camera error. If this was just a shutter speed issue, the car may or may not be blurred, but because the fence pole is also blurred, and they don't move it's obviously focusing or panning error.

The pole (fence, lines on road etc) should be dead sharp and in focus at around 1/50th so anything over that will keep that sharp and only the car should be blurred. In your case it's not.

03-03-2012, 06:52 PM   #39
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This is my point ,A and B look equally exposed. But changing the shutter from 1/160 to 1/6000, without changing the aperture or ISO is also a (more than) 4 stops difference. Therefore it should be B that looks radically different from the other two (A should look like C).
03-03-2012, 07:15 PM   #40
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QuoteOriginally posted by NeatKnight Quote
This is my point ,A and B look equally exposed. But changing the shutter from 1/160 to 1/6000, without changing the aperture or ISO is also a (more than) 4 stops difference. Therefore it should be B that looks radically different from the other two (A should look like C).
Then your camera is broken. The only explanation.
03-03-2012, 08:10 PM   #41
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What's up with the "shutter speed" in the exif, what do those numbers mean? They don't seem to be related to the 1/6000 or 1/160. 12.5507 on one pic, 7.32193 on the other.
03-04-2012, 12:20 AM   #42
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QuoteOriginally posted by Ex Finn. Quote
Then your camera is broken. The only explanation.
Or, there was a lot less light in the second shot. It looks that way to me, the first you can see the ground is in full sun. The second looks much more shaded. They're also not shot from the same vantage point, which may have something to do with it. Test shots like that should be shot from the exact same point, in quick succession if the light levels are likely to change at all.
03-04-2012, 01:28 AM   #43
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Here are two better test shots.
Maybe still not quite the same position as they were handheld, but probably close enough.
Both were shot at f10, iso 800,
but one was shot at 1/1250 second and the other was shot at 1/6000
I see almost no difference at all.
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03-04-2012, 03:19 AM   #44
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What lens are you using here?
03-04-2012, 03:24 AM   #45
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Well for testing the shutter you should go to Tv settings and let the camera change other things. You are too much looking at the image lightning, where you want to know if your shutter is doing what you want it to do.
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