Re: Question about zoom

> >> Also, the image editing program has better resizing so you would end up
> >> with
> >> higher quality than what you would get with digital zoom in the camera. I
> >> doubt the camera uses bicubic resampling. In Photoshop CS2 the Bicubic
> >> Sharper works quite well.
> > Regardless of the algorithm used... if the camera is throwing away data
> > in the final step, digital zoom will still have more of this data, and
> > no sophisticated resampling algorithm can recover it from a JPEG where
> > it's been thrown away.
> >
HornBlower wrote:
> Not if you are not using digital zoom, you do the effect in Photoshop. Then
> the cameras is only doing noise reduction, sharpening a few other things. It
> isn't cropping and then resizing.

To make myself clear again...

Digital zoom provides data that would be otherwise thrown away in a
JPEG.
_No algorithm_ in Photoshop can recover this data from a JPEG that's
not digitally zoomed - all it can do is work with what is there and try
to invent the rest.

Try my experiment a few posts back. Use all the noise reduction and
sharpening algorithms you want in conjunction with the resample - but
you have to also do it on the digitally zoomed image, and compare with
that.

.

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