High resolution...through digital interpolation...

My camera takes photos in normal resolution but claims to be able to take
finer photos at a higher pixel-rate through "digital interpolation".
Surely that's just stretching the image and not worth doing?
Can't I improve the image to the same degree later using filters in Corel
Photopaint?

Is there any real advantage in terms of image quality between an image
that's been digitally interpolated to a higher resolution?
It's no substitute for a higher resolution CCD in the camera is it?

D.

In article ,
says...
My camera takes photos in normal resolution but claims to be able to take
finer photos at a higher pixel-rate through "digital interpolation".
Surely that's just stretching the image and not worth doing?
Can't I improve the image to the same degree later using filters in Corel
Photopaint?

Is there any real advantage in terms of image quality between an image
that's been digitally interpolated to a higher resolution?
It's no substitute for a higher resolution CCD in the camera is it?

D.




On some cameras the improvement is there but only slight, on others its just
an up-sizing that gives you a bigger picture, but not a better one.

Fuji makes several that "interpolate upward" and on the S7000 there is
USUALLY some improvement, but the file is twice as big, but NOT 2 times
better. (at any rate, doubling the pixels dosent double the quality anyway,
even if you increase the sensor count, twice as many isnt twice as good, only
twice as big).



--
Larry Lynch
Mystic, Ct.

In article ,
says...
My camera takes photos in normal resolution but claims to be able to take
finer photos at a higher pixel-rate through "digital interpolation".
Surely that's just stretching the image and not worth doing?
Can't I improve the image to the same degree later using filters in Corel
Photopaint?

Is there any real advantage in terms of image quality between an image
that's been digitally interpolated to a higher resolution?
It's no substitute for a higher resolution CCD in the camera is it?

D.




On some cameras the improvement is there but only slight, on others its just
an up-sizing that gives you a bigger picture, but not a better one.

Fuji makes several that "interpolate upward" and on the S7000 there is
USUALLY some improvement, but the file is twice as big, but NOT 2 times
better. (at any rate, doubling the pixels dosent double the quality anyway,
even if you increase the sensor count, twice as many isnt twice as good, only
twice as big).



--
Larry Lynch
Mystic, Ct.

On Tue, 05 Apr 2005 17:07:15 +0000, Des wrote:

My camera takes photos in normal resolution but claims to be able to take
finer photos at a higher pixel-rate through "digital interpolation".
Surely that's just stretching the image and not worth doing?
Can't I improve the image to the same degree later using filters in Corel
Photopaint?

Is there any real advantage in terms of image quality between an image
that's been digitally interpolated to a higher resolution?
It's no substitute for a higher resolution CCD in the camera is it?

D.

There's a simple rule on processing information
(photo/video/audi) digitally:

garbage in = garbage out

It's as simple as that. Any pixel that was not produced by light hitting
the sensor and having its colour properly registered, is not a real pixel.
Sure it may be there, but it doesn't represent any visual information that
was present in the scene when the photo was taken. It was calculated after
the fact and therefore it is artificial.

There is absolutely nothing that a digital process can do after the
picture was taken to add real pixels. It is simply impossible. Now of
course there are plenty of sharpening tricks that create a pretty good
illusion of detail on interpolated images. They're nothing more than
illusions though and you can only go a certain length before the fact that
your pixels are fake starts showing. If the camera gives you all the
pixels it actually captured, then it is in no way capable of more than
good interpolating on your PC.. like Photopaint.

In practice you can usually interpolate up to 125% or even 150% of the
original size, apply a sharpening filter and end up with a decent print.
The result however is no substitute for a higher real resolution.

I see this a lot on really cheap desktop scanners. They claim to go up to
14400dpi while their optics start to struggle beyond 600dpi. Years ago I
bought a $3000,- flatbed scanner that had lesser specs than my neighbor's
$100 scanner, at least when we compared the boxes they came in. Turned out
that 'my' 1000dpi. was a lot sharper than 'his'. All the result of
interpolation and good optics.

Bas

On Tue, 05 Apr 2005 17:07:15 +0000, Des wrote:

My camera takes photos in normal resolution but claims to be able to take
finer photos at a higher pixel-rate through "digital interpolation".
Surely that's just stretching the image and not worth doing?
Can't I improve the image to the same degree later using filters in Corel
Photopaint?

Is there any real advantage in terms of image quality between an image
that's been digitally interpolated to a higher resolution?
It's no substitute for a higher resolution CCD in the camera is it?

D.

There's a simple rule on processing information
(photo/video/audi) digitally:

garbage in = garbage out

It's as simple as that. Any pixel that was not produced by light hitting
the sensor and having its colour properly registered, is not a real pixel.
Sure it may be there, but it doesn't represent any visual information that
was present in the scene when the photo was taken. It was calculated after
the fact and therefore it is artificial.

There is absolutely nothing that a digital process can do after the
picture was taken to add real pixels. It is simply impossible. Now of
course there are plenty of sharpening tricks that create a pretty good
illusion of detail on interpolated images. They're nothing more than
illusions though and you can only go a certain length before the fact that
your pixels are fake starts showing. If the camera gives you all the
pixels it actually captured, then it is in no way capable of more than
good interpolating on your PC.. like Photopaint.

In practice you can usually interpolate up to 125% or even 150% of the
original size, apply a sharpening filter and end up with a decent print.
The result however is no substitute for a higher real resolution.

I see this a lot on really cheap desktop scanners. They claim to go up to
14400dpi while their optics start to struggle beyond 600dpi. Years ago I
bought a $3000,- flatbed scanner that had lesser specs than my neighbor's
$100 scanner, at least when we compared the boxes they came in. Turned out
that 'my' 1000dpi. was a lot sharper than 'his'. All the result of
interpolation and good optics.

Bas

Des writes:

My camera takes photos in normal resolution but claims to be able to take
finer photos at a higher pixel-rate through "digital interpolation".
Surely that's just stretching the image and not worth doing?

Correct.

Can't I improve the image to the same degree later using filters in Corel
Photopaint?

You can't improve an image through any type of manipulation. You will
never have better quality than the image had when originally recorded.
Interpolation is the creation of an optical illusion; it does not
improve real image quality.

Is there any real advantage in terms of image quality between an image
that's been digitally interpolated to a higher resolution?

No.

It's no substitute for a higher resolution CCD in the camera is it?

No, it's not.

--
Transpose hotmail and mxsmanic in my e-mail address to reach me directly.

Des writes:

My camera takes photos in normal resolution but claims to be able to take
finer photos at a higher pixel-rate through "digital interpolation".
Surely that's just stretching the image and not worth doing?

Correct.

Can't I improve the image to the same degree later using filters in Corel
Photopaint?

You can't improve an image through any type of manipulation. You will
never have better quality than the image had when originally recorded.
Interpolation is the creation of an optical illusion; it does not
improve real image quality.

Is there any real advantage in terms of image quality between an image
that's been digitally interpolated to a higher resolution?

No.

It's no substitute for a higher resolution CCD in the camera is it?

No, it's not.

--
Transpose hotmail and mxsmanic in my e-mail address to reach me directly.

Larry writes:

On some cameras the improvement is there but only slight, on others its just
an up-sizing that gives you a bigger picture, but not a better one.

There is never an improvement.

Fuji makes several that "interpolate upward" and on the S7000 there is
USUALLY some improvement ...

There is never any improvement. It's a mathematical impossibility.

--
Transpose hotmail and mxsmanic in my e-mail address to reach me directly.

Larry writes:

On some cameras the improvement is there but only slight, on others its just
an up-sizing that gives you a bigger picture, but not a better one.

There is never an improvement.

Fuji makes several that "interpolate upward" and on the S7000 there is
USUALLY some improvement ...

There is never any improvement. It's a mathematical impossibility.

--
Transpose hotmail and mxsmanic in my e-mail address to reach me directly.

Des wrote:
My camera takes photos in normal resolution but claims to be able to take
finer photos at a higher pixel-rate through "digital interpolation".
Surely that's just stretching the image and not worth doing?
Can't I improve the image to the same degree later using filters in Corel
Photopaint?

Is there any real advantage in terms of image quality between an image
that's been digitally interpolated to a higher resolution?
It's no substitute for a higher resolution CCD in the camera is it?

D.


It is marketing, just like 'digital zoom'. Many 'enhanced digital
zooms' do basically the same thing, interpolating to a larger size, then
cropping.
It's mostly smoke and mirrors, but the pictures usually DO look
smoother, just not more detailed.


--
Ron Hunter