Steady Shot - how does it work?

[pikey]

The title says it all really.

Bloody clever. Anyone have a clue how it works... and also any disadvantages of using it?

Thanks


PS. Referring to "Steady Shot" feature on the Sony a100

[graham@edinburgh]

Gyroscopes and gimbals presumably. Much like Canon's Image Stabilisation feature.

[poah]

a gyroscope detects movement then the sensor moves to compensate. usefull on short lenses but not as effective with longer ones

[RobDickinson]

If its a moving the CCD version disadvantages are power use (battery life) & heat buildup (CCD's work poorer when hotter), also sometimes can make panning shots a problem.

[robbieduncan]

graham@edinburgh said:

Much like Canon's Image Stabilisation feature.

The difference being that Canon's works in the lens, Sony's works in the body. Canon's can be tuned to each lens enabling larger movements for longer lenses so is considered better by some, but means that you have to spend more as the IS system is per lens.

[fergusd]

I'd be highly surprised if the CCD actually moves . . . more likely these days (in cheap systems) that it's done in software and the CCD is actually larger than the visible image you see . . . allowing the software to use the parts of the CCD you can't see to remove the vibration effect . . .

The canon/nikon/whatever in lens systems move a lens element(s) to effectively move the image on the fixed sensor . . .

SLR's can't use the same tech as a camcorder or compact as their sensors don't actually see the image until you press the shutter, whereas in a compact or camcorder the sensor sees the image all the time.

Fd

[RobDickinson]

fergusd said:

SLR's can't use the same tech as a camcorder or compact as their sensors don't actually see the image until you press the shutter, whereas in a compact or camcorder the sensor sees the image all the time.

Fd

Bollox, some dSLR's use sensor moving Image stabalisation, just not Canon or Nikon.

You dont then get to see the 'result' in the viewfinder though some dSLR's now show 'live' pics on the LCD too.

[graham@edinburgh]

RobDickinson said:

fergusd said:

SLR's can't use the same tech as a camcorder or compact as their sensors don't actually see the image until you press the shutter, whereas in a compact or camcorder the sensor sees the image all the time.

Fd

Bollox, some dSLR's use sensor moving Image stabalisation, just not Canon or Nikon.

You dont then get to see the 'result' in the viewfinder though some dSLR's now show 'live' pics on the LCD too.

Olympus do that I think.

[robbieduncan]

fergusd said:

SLR's can't use the same tech as a camcorder or compact as their sensors don't actually see the image until you press the shutter, whereas in a compact or camcorder the sensor sees the image all the time.

The Sony system does move the sensor. The time the sensor is exposed is non-zero. So the IS system is trying to compensate for movements during the exposure.

[cannedheat]

poah said:

a gyroscope detects movement then the sensor moves to compensate. usefull on short lenses but not as effective with longer ones

I thought it was was more usefull/effective on longer lenses? I can't imagine using a 200mm+ lens without IS...

[RobDickinson]

cannedheat said:

poah said:

a gyroscope detects movement then the sensor moves to compensate. usefull on short lenses but not as effective with longer ones

I thought it was was more usefull/effective on longer lenses? I can't imagine using a 200mm+ lens without IS...

I think IS is more usefull on longer lenses, but sensor stabalisation (compared to in lens optical stabalisation) is less effective.

[robbieduncan]

cannedheat said:

poah said:

a gyroscope detects movement then the sensor moves to compensate. usefull on short lenses but not as effective with longer ones

I thought it was was more usefull/effective on longer lenses? I can't imagine using a 200mm+ lens without IS...

IS may be more useful on longer lenses. I think the post was meant to say that moving the sensor instead of a lens element gets less effective as the lens gets longer...

[pikey]

When the system is enabled there is a 5 bar scale in the view finder that shows how much movement the camera has at that moment. The instructions say that you should use that as a guide as when it's at 5 bars the system cannot compensate anymore.

To the earlier question, yes, it's on the camera. It's a selling point that you can use any old lens and still benefit from the stabilisation feature.

What I would like to know is HOW it works. Does it really move the CCD or does it compensate with software. If so, what does the software actually do? (Please bear in mind I don't know how the software works in a video camera / Canon lens with stabilisation either.)

Pikey

[robbieduncan]

pikey said:

What I would like to know is HOW it works. Does it really move the CCD or does it compensate with software. If so, what does the software actually do? (Please bear in mind I don't know how the software works in a video camera / Canon lens with stabilisation either.)

There's an ultra brief explanation (and test) here: www.dpreview.com/reviews/sonydslra100/page14.asp

Basically: yes it moves the sensor based on the input from one or more gyroscopes.

[pikey]

robbieduncan said:

There's an ultra brief explanation (and test) here: www.dpreview.com/reviews/sonydslra100/page14.asp

Blimey! That's a mouthful for a layman like me! Thanks though. I'll re-read it again in the morning

[RobDickinson]

Ah its the sony system.. Then its the KM system I had on my A2.

The sensor is mounted on a plate which is moved by motors in accordance to instructions from gyroscopes.

[tog]

Sometimes image stabilisation just means turning up the ISO, which isn't the same thing at all. Be careful with stabilisation claims made for some compacts.

More here: www.dpreview.com/news/0701/07010501notimagestabilization.asp

[fergusd]

RobDickinson said:

Bollox, some dSLR's use sensor moving Image stabalisation, just not Canon or Nikon.

You dont then get to see the 'result' in the viewfinder though some dSLR's now show 'live' pics on the LCD too.

I was referring to image processing not moving sensor mechanisms, had you bothered to read . . .

Fd

[RobDickinson]

fergusd said:

RobDickinson said:

Bollox, some dSLR's use sensor moving Image stabalisation, just not Canon or Nikon.

You dont then get to see the 'result' in the viewfinder though some dSLR's now show 'live' pics on the LCD too.

I was referring to image processing not moving sensor mechanisms, had you bothered to read . . .

Fd

Theres still on inherent difference between the two camera typs, being able to 'see' the image on the sensor or not doesnt make a bit of difference, IS is controled by gyroscopes not what the sensor see's.

Selling a high ISO mode as IS sounds like its pushing the bounds of legality quite some way

But the OP has a sony(KM) dSLR which moves the sensor, worked quite well on my KM A2.

[Zad]

The new Pentax K10D has it's own image stabilisation system built into the body too. Not only does it compensate for translation shake (horizontal, vertical) but it compensates for rotational movement too. The camera seems to be aimed at somewhere above the Eos 400d and Nikon 80d but for not much more dosh. I have PK manual lenses so I have an interest in seeing how the K10D works in the real world.