Samsung Digimax V700

Anyone tried it yet? How good is the flash with this camera? Is the video
stabilizer effective? I tried to find a video sample from this camera but
found none on the net...
Sylvain

 

Yes, I have just seen this yesterday! Another cool feature of the V700 is
that you can "pause" a video. I have just seen on dcresource a Kodak camera
that will be shipped in july. The camera is Kodak EasyShare V530 and it is
supposed to allow zooming during filming! Also coming is the Casio
introduces Exilim EX-S500
which is also equipped with digital image stabilizer for movie! Too many
camera with cool feature are getting out, I think I'll wait a couple of
month before choosing one...

Sylvain

 

Hi,
Digital stabilizer? What's good for it.
My old Sony TRV900 has optical stabilizer.(real thing)
Tony

 

Invariably? Yes. Digital is limited to increments of the pixel
spacing unless it interpolates. Optical is not. Can closed.

 

Shifting an image by a fraction of a pixel is pretty easy. I wouldn't
conclude that no camera with digital stabilization is capable of this.

I think the important difference is this: When optical stabilization is
working properly, the image is stationary on the sensor, and each
individual frame of video is sharp. When only digital stabilization is
used, the image is continuously moving on the sensor, and each single frame
is blurred by that motion. The stabilization process can remove the
large-scale movement over many frames, but it can't fix that blur.

All of the still cameras that I know of with image stabilization use
optical stabilization in the lens, except for the one that does the
stabilization by mechanically moving the sensor.

Nobody uses digital image stabilization in a still camera, because if
you're taking one still image you want that one image to be sharp.
It's not useful to be able to align a sequence of blurry images.

Dave

 

Dave Martindale wrote:
[]

I can cite one possible exception to this - when taking video the Nikon
Coolpix 8400 can use electronic image stabilisation (it has no optical
stabilisation). However, when it does this the video resolution is a
maximum of 640 x 480 pixels, far lower than the basic sensor resolution
(8MP).

Of course, you could argue that this /isn't/ a still camera in this mode,
and in any case the slight blur may be much less noticeable in a moving
image!

Cheers,
David

 

Actually, shifting an image by a fraction of a pixel is impossible
-- 'unless it interpolates' -- as I originally said.

And if it does interpolate, then it is going to give a worse image
than one created by shifting the optical path.

That's one factor.

Add to that your point -- to state it somewhat differently -- the fact
that optical stabilization can keep the image centered on the
same pixels over the entire duration of the exposure, and the
advantage of optical is obvious.

The only way a digital scheme would even come close to optical
would be if were able to capture many frames over the duration
of the exposure, shift each slightly to eliminate the motion, and
composite them into a single image. But if you really could
capture multiple frames over the exposure, that implies that the
longer exposure wasn't really necessary in the first place. And
even if it is done that way, there is still the issue of image
degradation due to interpolation effects.

 

If you're shooting video, it's useful to remove the large-scale motion
even if the camera can't fix the blur.

Dave

 

"Interpolation" is a vague term that can refer to any method to
calculate new values from existing data. It may lose information, or
it may not - it depends on the technique used.

Shifting an image by a fraction of a pixel would be done by an image
resampling technique. Image resampling is a type of interpolation, but
it's done with well-studied algorithms and on data whose spatial
frequency content is known. *This* can be done with no visible loss of
information at all.

Your argument is basically that shifting using resampling will
necessarily make the image quality worse - and that's just not true.

Dave

This is the real reason that optical stabilization is better.

Dave

 

Yes, indeed. The results on video are very good for a stills camera!

Cheers,
David

 

No, not any resampling -- partial pixel shift resampling. I've never
seen it done that doesn't result in diagonals looking worse than prior
to the resampling.

 

What algorithm was used for the resampling?

I'd offer to run a test on some sample image of your choice using my own
resampling software (which is nothing special, but I know how it works
internally) except my Linux machine is currently being reconstructed.

If you're interested in the experiment, send a sample image with
diagonals and I'll try it when the software is running again.

Dave