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09-15-2016, 04:11 PM   #16
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QuoteOriginally posted by Winder Quote
K-7 has a delay in the SR. You had to wait a second or two for it to come on and work. It was pretty average.

Its hard to really test SR. I found the K-3 to be good for about 5 or 6 beers. After that it starts to get a little blurry. K-1 is definitely better. It's not just in how many beers it can compensate for, but its fast and you can shoot quick. Previous generations had lag where the camera would focus and you were ready to shoot, but the SR was not ready. The new SR is quick and does a great job. I would expect the K-70 has the same level of performance as the K-1. The smaller sensor is ligher and easier to move.

my shake gets better with more beer! subject matter, well that's another story

Randy

09-15-2016, 04:48 PM   #17
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I don't know if this helps, but from some EXIF data from a series of photos I took with my K-5 either with the 18-55 WR or Tamron 28-75 anything with a half shutter press below 0.58 s was either Not Ready or Not Stabilized and anything longer than 0.60 s was stabilized. I realize you were asking about stops, but time to engage may also be of some importance.

Last edited by MSL; 09-15-2016 at 07:21 PM. Reason: added details
09-24-2016, 01:43 PM   #18
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QuoteOriginally posted by Lowell Goudge Quote
pixel size, pixel pitch and pixel density have nothing at all to do with shake reduction and shutter speed.

lets go back to the basis of the rule of thumb, which was for 35mm film cameras shutter speed should be 1/focal length, to get a full frame image when enlarged to 8 x 10, where there is no "acceptable blur"

acceptable blur was defined as a point of light remaining smaller than 0.01 inch in diameter, or what was considered when viewed from arms length as indistinguishable from a true point. (note this is the same criteria used for acceptably sharp when discussing depth of field)

when you consider an APS-C camera, you need to add the crop factor, because the enlargement of the basic image is 50% higher, to get back to an 8 x 10 inch print.

if you are viewing at the pixel level, you are enlarging at much higher magnifications and it is not how you should measure shake reduction efficiency. in this case, you need to add, in the shutter speed calculation (basic rule of thumb) the linear magnification ratio compared to the base 8 x 10 reference used for acceptable sharpness.


you also need to consider that for the K1, being a full frame camera, for example, that the shake reduction may appear to be more effective because the final magnification of the sensor image to the print is less than for a cropped sensor
This may be how this is counted, but this is not how people will count it. People will go look at the 100% crop and see if this is sharp or not. Even between 2 bodies with same number of pixels like K5 and K5-IIs the removal of the low pass filter will make a difference. As well as the number of pixels, because this increase magnification.

The sensor format should not be a factor at all to me, because when switching format, it make sense to speak of equivalence: similar field of view. This mean same requirements for SR by your own definition. So no change at all.

But for user perception when looking at a 100 crop, K1 has more pixels, so people will notice blur sooner whatever the official way of measuring SR.

Anyway the efficiancy depend of what type of shake you have, the focal length and actual shutter speed. The claim always seems to be a bit optimistic. 4.5 stop mean I should be able to have a sharp image on APSC with 15mm handed at 1s shutter time, a 50mm at 1/3s shutter time or a 300mm at 1/20... This look to be a bit optimistic for me. In practice SR seems to be more about 1.5-2.5 stop to me, it being more effective with longer focal length. That's already quite nice.

Last edited by Nicolas06; 09-24-2016 at 01:49 PM.
09-24-2016, 04:50 PM   #19
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QuoteOriginally posted by Nicolas06 Quote
This may be how this is counted, but this is not how people will count it. People will go look at the 100% crop and see if this is sharp or not. Even between 2 bodies with same number of pixels like K5 and K5-IIs the removal of the low pass filter will make a difference. As well as the number of pixels, because this increase magnification.

The sensor format should not be a factor at all to me, because when switching format, it make sense to speak of equivalence: similar field of view. This mean same requirements for SR by your own definition. So no change at all.

But for user perception when looking at a 100 crop, K1 has more pixels, so people will notice blur sooner whatever the official way of measuring SR.

Anyway the efficiancy depend of what type of shake you have, the focal length and actual shutter speed. The claim always seems to be a bit optimistic. 4.5 stop mean I should be able to have a sharp image on APSC with 15mm handed at 1s shutter time, a 50mm at 1/3s shutter time or a 300mm at 1/20... This look to be a bit optimistic for me. In practice SR seems to be more about 1.5-2.5 stop to me, it being more effective with longer focal length. That's already quite nice.
You missed the point. Shake reduction and minimum shutter speed is all about the total magnification. A 300mm lens will need 10x faster shutter speed than a 30mm lens because the lens magnification is 10x higher

If you crop in from 35 mm full frame to APSC and then print back to the same finished print size, you need 50% more shutter speed just because you are ellarging the image more.


So if you want to look at things at the pixel size then you need even higher shutter speed because you are enlarging even mode.

Do some reading about circles of confusion you will understand it better.

09-24-2016, 11:59 PM   #20
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QuoteOriginally posted by Lowell Goudge Quote
You missed the point. Shake reduction and minimum shutter speed is all about the total magnification. A 300mm lens will need 10x faster shutter speed than a 30mm lens because the lens magnification is 10x higher

If you crop in from 35 mm full frame to APSC and then print back to the same finished print size, you need 50% more shutter speed just because you are ellarging the image more.
But you'll also use a focal length that is 33% shorter on APSC vs FF because you are framing/field of view driven and not focal length driven. So in the end, that exactly the same.

When i use a 24mm on FF, to get the same framing on APSC I use a 16mm. In the end that's the same. The translation speed for X, Y or Z axis are the same in intensity. And the rotation also have to be the same angle for X, Y, Z axis respectively on both sensors. Because the FF sensor is bigger/heavier overall this put more constraints on it than on the APSC sensor. The SR need more strength to move the FF sensor and the absolute movement at the sensor extremities are bigger to achieve the same rotation angles on the FF.

What you say is right too but apply only when I shoot the same focal length for both APSC and FF, meaning I'll get totally very different framing on both and assuming that I want theses different framing. That doesn't make sense except if actually I care only on the center APSC crop meaning I have actually 2 APSC bodies and so the level of SR to apply is the same, except on the FF I still need to move the whole sensor and still need more sturdy SR to achieve that.
09-25-2016, 12:36 AM   #21
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Its worth noting that at the long shutter time end, things get increasingly difficult for any mechanism.
Times longer than 1/4 of a second are getting really difficult for any IS or SR to handle, so you get better numerical SR effectiveness with 100-300mm lenses than with a 12mm, because the resulting times get too long on shorter focal lengths.
09-25-2016, 01:21 AM   #22
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QuoteOriginally posted by beholder3 Quote
Its worth noting that at the long shutter time end, things get increasingly difficult for any mechanism.
Times longer than 1/4 of a second are getting really difficult for any IS or SR to handle, so you get better numerical SR effectiveness with 100-300mm lenses than with a 12mm, because the resulting times get too long on shorter focal lengths.
Yep ! And really I'd love to see SR that would allow me 1s shutter time with 15 (4.5 stop) or 21mm (5 stops). That would mean night landscapes at moderate to low isos handled.
09-25-2016, 01:27 AM   #23
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QuoteOriginally posted by Nicolas06 Quote
Yep ! And really I'd love to see SR that would allow me 1s shutter time with 15 (4.5 stop) or 21mm (5 stops). That would mean night landscapes at moderate to low isos handled.
I recently shot a night sky handheld at 1/2 second with 35mm F1.4 (ISO 6400). That is ambient light level -4.

The best time I achieved in real life shooting was 1 second at 16mm (24mm FF) using a K-3II, but that took 5 or 6 tries.

09-25-2016, 05:21 AM   #24
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QuoteOriginally posted by beholder3 Quote
I recently shot a night sky handheld at 1/2 second with 35mm F1.4 (ISO 6400). That is ambient light level -4.

The best time I achieved in real life shooting was 1 second at 16mm (24mm FF) using a K-3II, but that took 5 or 6 tries.
But I think we can agree that this is not reliable... You can't count on 1/2s or 1s shoots to work handled

Anyway nice performance
09-25-2016, 05:47 AM   #25
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QuoteOriginally posted by Nicolas06 Quote
But you'll also use a focal length that is 33% shorter on APSC vs FF because you are framing/field of view driven and not focal length driven. So in the end, that exactly the same.

When i use a 24mm on FF, to get the same framing on APSC I use a 16mm. In the end that's the same. The translation speed for X, Y or Z axis are the same in intensity. And the rotation also have to be the same angle for X, Y, Z axis respectively on both sensors. Because the FF sensor is bigger/heavier overall this put more constraints on it than on the APSC sensor. The SR need more strength to move the FF sensor and the absolute movement at the sensor extremities are bigger to achieve the same rotation angles on the FF.

What you say is right too but apply only when I shoot the same focal length for both APSC and FF, meaning I'll get totally very different framing on both and assuming that I want theses different framing. That doesn't make sense except if actually I care only on the center APSC crop meaning I have actually 2 APSC bodies and so the level of SR to apply is the same, except on the FF I still need to move the whole sensor and still need more sturdy SR to achieve that.
A framing and field of view have nothing to do with it. It is strictly the ratio of magnification of subject to final enlargement.

As for the energy the system need yes for the same displacement of the sensor, but by your argument since you want to go down the path of field of view,my ou need smaller movement for full frame so that washes out , but any way, back to the original discussion. The claim of efficiency is all about how much you enlarge an image and the issue is when you go to the pixel level you have increased the overall magnification. As a result, you cannot, under that magnification use the 1/focal length rule of thumb regardless of format
09-25-2016, 06:30 AM   #26
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I'd like to see a test bench fixed to small electrohydraulic actuators (similar to those used in earthquake simulators but on a much smaller scale) where cameras could be mounted and tested. If the shake pattern was fixed, and there were multiple shake patterns to test, then it seems we'd have a method of testing SR to some degree.
09-25-2016, 06:45 AM   #27
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Secret standards which Nikon, Canon, Sony, Pentax use exist already:
CIPA standard for shake reduction not available to the public: Open Talk Forum: Digital Photography Review

I have no reason to assume they are defined in any way differently from car gas consumption standards - 100% in the interest of the consumer and 100% realistically.
09-25-2016, 07:50 AM   #28
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QuoteOriginally posted by beholder3 Quote
Secret standards which Nikon, Canon, Sony, Pentax use exist already:
CIPA standard for shake reduction not available to the public: Open Talk Forum: Digital Photography Review

I have no reason to assume they are defined in any way differently from car gas consumption standards - 100% in the interest of the consumer and 100% realistically.
I don't know what people trust or not, honestly but basically I know SR improve thing noticably... But on the opposite I don't trust one bit the 4.5 stop thing. Too good too be true and not what I experience... A bit like the car that are rated to consume 3.6l/100km (or if you prefer would do 60 miles with 1 gallon)...
09-25-2016, 09:29 PM   #29
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If you don't know when and how to use SR, and remember to set and use it as intended, it doesn't matter what the relative advantage of SR is. Like most other characteristics of photography gear and functions the results achieved are on a bell curve of situational efficiency that's solely dependent upon the photographer's knowledge, skill and appropriate use.

The greatest advantage of a DSLR over an SLR is the ability to optimize ALL parameters on a shot-to-shot basis and have immediate feed back as to how wrong you were - now If I could just consistently remember to use that advantage . . .
09-26-2016, 05:04 AM   #30
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QuoteOriginally posted by Nicolas06 Quote
Yep ! And really I'd love to see SR that would allow me 1s shutter time with 15 (4.5 stop) or 21mm (5 stops). That would mean night landscapes at moderate to low isos handled.
I know of a shake reduction system for this, and it works really great for much longer shutter speeds than 1s.
And a bonus is that you don't even need to hold the camera.
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