Luminous Landscape Forum

Raw & Post Processing, Printing => Digital Image Processing => Topic started by: cocasana on December 15, 2008, 01:18:46 am

Title: PS CS4's Resize Image new feature
Post by: cocasana on December 15, 2008, 01:18:46 am

Hi there. Does anybody know something interesting on this new resizing option? When to use it? Pros & cons? Thanks, Carlo

Title: PS CS4's Resize Image new feature
Post by: walter.sk on December 15, 2008, 09:39:41 am

I think Nearest Neighbor has been a choice for interpolation at least since Photoshop 4.5!

Title: PS CS4's Resize Image new feature
Post by: madmanchan on December 15, 2008, 09:46:25 am

Basically, never use it for photographs.

Useful occasionally for resizing profile targets.

Title: PS CS4's Resize Image new feature
Post by: cocasana on December 15, 2008, 10:03:49 am

Walter, you are right!

Thanks Eric!

Title: PS CS4's Resize Image new feature
Post by: Guillermo Luijk on December 15, 2008, 01:05:27 pm

It has been into PS for a long time. For rescaling down has some properties: it keeps the SNR (other algorithms improve SNR) and enhances sharpness without producing any hallos.
The drawbacks are that it generates terrific aliasing artifacts when geometrical patterns are present in the scene.

For Web rescaling down it is nice to try the following:
1. First rescale with Bicubic to twice the final desired size (e.g. if the final JPEG will be 800px wide, rescale with Bicubic to 1600x)
2. Next rescale with Nearest neighbour (it's called Aproximation on the Spanish CS2) to the final size: 800px

This gives good sharpness for natural shaped objects and landscapes:

(http://www.guillermoluijk.com/tutorial/websharp/vista.jpg)

Not always works.

Title: PS CS4's Resize Image new feature
Post by: cocasana on December 15, 2008, 02:17:08 pm

Thanks GLuijk I will try it!!!!