Image Stabilization: Digital v. Optical (1 Viewer)

[mtn_biker2]

I have a theory - wondering if anyone can confirm or deny...

Optical IS adjusts the lens to stabilize the image. Digital does it, well, digitally. While the optical version is considered better (doesn't mess w/ the image) digital IS may be better for digiscoping.

My theory is optical IS won't help you if it's the scope that's moving while digital IS may not know the diffence if it's the scope or the lens - it's working with the digital image in the processor.

Any thoughts or comments?

 

[RAH]

"Optical IS adjusts the lens to stabilize the image." In the case of point-and-shoot cameras, and even many DSLRs, this is not correct. Most point-and-shoots adjust the sensor to stabilize the image - i.e. they shake the image sensor in the opposite direction from the perceived instability. Some DSLRs, namely Canon and Nikon, have the stabilization built into the lens, but others like Olympus, Pentax, Sony, etc, use the sensor method for stabilzation, just like point-and-shoots.

The question then is whether these systems recognize shake in an external device like the scope, which is placed in front of the lens. It depends, I guess, on whether they work based on the image that is striking the sensor - i.e. is it moving? - or whether they work by detecting movement of the camera itself (i.e. you are shaking it). If it only works by detecting camera shake, then for sure it won't help with scope shake.

 

[Paul Corfield]

Some info I found on the web which should help. Rest of article is on the link at the end.

Stabilization styles
Here’s a closer look at the stabilization options you’ll probably find at the camera counter.

Optical Stabilization
Used in compact cameras and SLRs, optical stabilization is the most common image-stabilization method. Different manufacturers have different names for it: Nikon calls its optical stabilization Optical Vibration Reduction when referring to cameras, and VR when referring to lenses. Canon calls its optical stabilizer the Image Stabilizer (IS); Panasonic, the Mega O.I.S.; and Sigma, the Optical Stabilizer (OS) system.

Optical stabilization uses gyroscopes within the camera or the camera’s lens to detect camera shake, and then steadies the path of the image as it makes its way to the camera’s sensor (CCD). Canon, one of the first companies to develop this technology, employs a floating lens element that moves in the opposite direction of the shake. For instance, if you suddenly move the camera upward while snapping your shot, the floating lens element moves the other way, thus stabilizing the image as it heads toward the sensor. In SLRs, the gyroscopes are often located in the lens; in point-and-shoots, they are positioned in the body (since there is no room in the lens on these tiny shooters).

Sensor Stabilization
This technology works similarly to optical stabilization: with sensor stabilization, gyroscopes located in the camera body detect shake and then move the image sensor to counteract the motion. Although it’s available on some point-and-shoots, sensor stabilization is more commonly used in SLRs. Olympus refers to this technology as Sensor-Shift Image Stabilization; Pentax, Shake Reduction; and Sony, Super SteadyShot.

Digital Stabilization
Unlike optical and sensor stabilization, which actually correct the image while you’re capturing a picture, digital stabilization attempts to make a picture clearer by changing the camera’s settings or by attempting to alter the image after it has been captured. There are several different approaches to digital stabilization. One of the most useful is Intelligent ISO. Used primarily in compact cameras, an Intelligent ISO feature automatically increases the ISO, or light-sensitivity, setting when the image sensor detects a moving object. As a result, the camera is able to use a faster shutter speed to snap a picture, thus freezing the motion of the subject and reducing blur. When the subject stops moving, the camera automatically returns to a lower ISO setting. This last part is important because higher ISO settings also tend to produce more image noise. Panasonic includes an Intelligent ISO control in many of its cameras, while Fuji employs a similar approach called Picture Stabilization.

http://www.macworld.com/article/58780/2007/07/augdigitalphoto.html?t=216

Paul.

 

[RAH]

Interesting. Sounds like IS would not help scope shake, unless the scope were firmly attached directly to the camera and they both shook together.