Whaz USM??

[engr]

Yo folks, newbie here. Been seeing this abbreviation USM. Whaz that ah? Can enlighten me? Seems to be some process that can improve picture quality.. Thanks..

 

[goering]

You are probably referring to the Unsharp Mask (USM) of Photoshop - a process to sharpen pics - but I actually find this term strange

USM is also commonly used to refer to the Ultrasonic Motor of Canon lenses -an entirely different thing

 

[nipapa]

USM is unsharp mask. It is a real stupid name for a filter that is supposed to sharpen photos. It can be found in most photo editing programs. (eg : Photoshop) Basically what it does is that between 2 colours, eg a leaf and a tree, it enhances the contrast between the green and the brown with a little (glow), thereby making the leaf "stand-out ". "sharpening" it. It's powers, to me (pls correct me if i'm wrong), is only good if the pic is slightly blur. For totally cannot-make-it photos. USM is useless

you can visit :
http://www.planetphotoshop.com/peteback.html

and go to the topic :
Focus On Sharpening, Part 2

for more info.

 

[AReality]

USM is unsharp mask. It is a real stupid name for a filter that is supposed to sharpen photos.

Ahhh...
Going to explain why it is called UnSharp Mask...

It all goes back to the traditional darkroom.
There will be a separator who will make a pin-registered contact negative of the original image. To soften the mask, the artist will place a piece of frosted film between the original and the masking film.
This soft, mask (unsharp mask) will increase the edge contrast, making the image look sharper.




Ok ok. Easier explanation...
The USM for photoshop masks out the unsharpened part of the image; the unsharpened part is taken away. Leaving the sharpened part only...

 

[engr]

Ooh thank you all bros & sis for helping! Enlightened...

 

[singscott]

:thumbsup: for AReality. He is right folk it is a very little know fact, only "expert" knew. :bigeyes:

 

[nipapa]

haha oops *bleag*