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05-17-2009, 02:56 PM   #3151
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QuoteOriginally posted by blende8 Quote
1/180 s flash sync is wrong.
1080i is also wrong.
That is one prediction that better be on the mark. I am quite certain that I will never buy another 1/180 synch camera no matter what else it has to offer.

05-17-2009, 03:01 PM   #3152
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QuoteOriginally posted by GoldenWreckedAngle Quote
That is one prediction that better be on the mark. I am quite certain that I will never buy another 1/180 synch camera no matter what else it has to offer.
The press text mentions the new 1/8000s shutter speed but no word about flash sync speed.
05-17-2009, 03:01 PM   #3153
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QuoteOriginally posted by kolouch Quote
From my experience with K10D and various wireless controlers, It doesn't work at 1/180 there is a black strip in th bottom of the photo . usable is 1/125 . I wanna full functional x-sync (this problem is on every k10d with most of controlers).
It doesn't depends on camera but more from flashgun i suspect. Did you try any of PT04TMv2s?
05-17-2009, 03:05 PM   #3154
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QuoteOriginally posted by Gimbal Quote
There are motors, just engage the antidust system and feel them shake the sensor quite violently. And with SR engaged they actively move the image sensor to counteract the shake, how much they move is dependent on focal length so that is way you manually have to enter the right length when using old lenses.
Youre right the antidust function does move the sensor by sequentially cycling the magnets, but I think the lens information only stiffens or loosens the 'brakes'. SR is reactive, not predictive. it doesn't initiate movement in anticipation of shake, it resists movement when it detects it.

05-17-2009, 03:08 PM   #3155
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QuoteOriginally posted by kolouch Quote
From my experience with K10D and various wireless controlers, It doesn't work at 1/180 there is a black strip in th bottom of the photo . usable is 1/125 . I wanna full functional x-sync (this problem is on every k10d with most of controlers).

Try HSS with studio lights ..

And when you're shooting moving action, always is better 1/250 then 1/180
Try better triggers... I've never had such a problem with Pocket Wizards... And sync speed has nothing to do with stopping an action - to stop the action buy faster strobes.
Sync speed is important when you need to kill the ambient light when using small strobes or if you don't want to close the aperture that much with powerful ones. And yes - sometimes 1/2EV is important.
BTW, there is a way to HSS with studio strobes, but not using Pentax equipment unfortunately...
05-17-2009, 03:43 PM   #3156
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QuoteOriginally posted by illdefined Quote
I think the lens information only stiffens or loosens the 'brakes'. SR is reactive, not predictive. it doesn't initiate movement in anticipation of shake, it resists movement when it detects it.
You have an incorrect idea about the algorithm behind the SR system. This isn't probably the thread to dig into this too deep.

In summary, imagine that the SR system observes rotation about two body axes and does a frequency analysis of them. Then, for each frequency, it detects its phase and amplitude, subtracts the latency of the SR mechanism from the phase, and retransforms the result into real space. It then multiplies the result by focal length and steers the magnets accordingly.

If you are lost by now (the anticipated effect of my explainations ), then you may just want to remember this:

It does anticipate movements. And there are no brakes
05-17-2009, 03:52 PM   #3157
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Isn't it only anticipating possible (ie probable or general vs. actual) movement and setting the magnets relative to focal length?
05-17-2009, 04:04 PM   #3158
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If the SR was purely reactive I would see no reason to have to turn it off when using a tripod.

05-17-2009, 04:05 PM   #3159
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QuoteOriginally posted by Gimbal Quote
Anyone written by Pentax?
http://www.pentaximaging.com/files/scms_docs/SHAKE_REDUCTION_FACT_SHEET.pdf
You're welcome!

The Nikon D700 has a virtual horizon mechanism where you can see and correct for off-axis rotation in the viewfinder using the same scale used for manual metering.
......|......

When the little tick is in the centre of the scale, the camera is horizontal (also works in vertical orientation). Would be nice if the K-7 had either that, or a mode where it could automatically correct for slight tilt. That would be cooool.
05-17-2009, 04:10 PM   #3160
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Are we sure it isn't K-z instead of K-7?
05-17-2009, 04:12 PM   #3161
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QuoteOriginally posted by falconeye Quote
You have an incorrect idea about the algorithm behind the SR system. This isn't probably the thread to dig into this too deep.

In summary, imagine that the SR system observes rotation about two body axes and does a frequency analysis of them. Then, for each frequency, it detects its phase and amplitude, subtracts the latency of the SR mechanism from the phase, and retransforms the result into real space. It then multiplies the result by focal length and steers the magnets accordingly.

If you are lost by now (the anticipated effect of my explainations ), then you may just want to remember this:

It does anticipate movements. And there are no brakes
That's why they recommend to switch SR off when using tripod.

edit: posted before reading Mutedphotos reply. sorry
05-17-2009, 04:16 PM   #3162
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QuoteOriginally posted by mysterick Quote
Are we sure it isn't K-z instead of K-7?
It could happen. We had it before: K-M in Europe and k2000 in Americas
05-17-2009, 04:19 PM   #3163
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QuoteOriginally posted by mutedphotos Quote
If the SR was purely reactive I would see no reason to have to turn it off when using a tripod.
good point. could also explain why it takes a second for SR to "kick in" when it is activated (it's analyzing). Would a more passive, reactive system be quicker? Is that how in-lens I.S. works?
05-17-2009, 04:19 PM   #3164
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QuoteOriginally posted by sezme Quote
http://www.pentaximaging.com/files/scms_docs/SHAKE_REDUCTION_FACT_SHEET.pdf
You're welcome!

The Nikon D700 has a virtual horizon mechanism where you can see and correct for off-axis rotation in the viewfinder using the same scale used for manual metering.
......|......

When the little tick is in the centre of the scale, the camera is horizontal (also works in vertical orientation). Would be nice if the K-7 had either that, or a mode where it could automatically correct for slight tilt. That would be cooool.
That would be nice but I don't believe the K-7 has it. One thing we haven't seen lately with Pentax is a sign on the right hand top plate indicating the plane of the sensor, for accurate distance measurements(macro)
05-17-2009, 05:42 PM   #3165
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QuoteOriginally posted by Asahiflex Quote
The shape is a 2-dimensional cube(?); maybe it's 3-D!
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