by Kernie » Fri Mar 29, 2013 11:25 pm
:bang: :bang: :bang:
Bottom line...
1) If you're going to use raster images, or raster versions of logos, NEVER scale them larger than their original dimensions. Pixellation will occur no matter what.
2) There are ZERO benefits to saving a raster image as an EPS file. EPS preserves vector path information. Raster files don't have vector path information... so it's basically useless. Use JPEG, PNG, TIFF, or GIF (if you must) for raster images. Then refer to #1 above.
3) EPS format is meant to be a common vector format compatible with a variety of programs. Use EPS when you have a vector file that you want to retain path information.
4) Photoshop's "Place" feature is meant to place images into a document as a Smart Object. Smart Objects "nest" the original image file with the PSD, so that when the Smart Object is scaled down to 10%, the user has the ability to scale it back to 100% without pixellation. The reason it does not pixellate is because the original resolution image is preserved within the smart object. (On the flipside, scaling a non-Smart Object to 10% and then resizing back to 100% will result in pixellation because the full size image info was lost when scaled to 10%). However, as with #1 above, scaling a Smart Object above 100% of its original resolution will result in pixellation. In a nutshell, any time you scale any raster file larger than 100% of its original size, you will get pixellation. This cannot be avoided. It is the nature of raster images.
5) Vector EPS files CAN be scaled larger than 100% because they are not based on definitive pixels, they are based off
vectors... mathematical points and curves that, when scaled, are re-interpreted to maintain crisp, clean edges. This is the primary benefit of using vector shapes and vector EPS files for logos, they can be scaled smaller and larger over and over again without ever having to worry about the file becoming pixellated... because there are essentially no "pixels" involved.
In my attempt to clarify things, I may be making them more complicated.

:bang: :bang: :bang:
Bottom line...
1) If you're going to use raster images, or raster versions of logos, NEVER scale them larger than their original dimensions. Pixellation will occur no matter what.
2) There are ZERO benefits to saving a raster image as an EPS file. EPS preserves vector path information. Raster files don't have vector path information... so it's basically useless. Use JPEG, PNG, TIFF, or GIF (if you must) for raster images. Then refer to #1 above.
3) EPS format is meant to be a common vector format compatible with a variety of programs. Use EPS when you have a vector file that you want to retain path information.
4) Photoshop's "Place" feature is meant to place images into a document as a Smart Object. Smart Objects "nest" the original image file with the PSD, so that when the Smart Object is scaled down to 10%, the user has the ability to scale it back to 100% without pixellation. The reason it does not pixellate is because the original resolution image is preserved within the smart object. (On the flipside, scaling a non-Smart Object to 10% and then resizing back to 100% will result in pixellation because the full size image info was lost when scaled to 10%). However, as with #1 above, scaling a Smart Object above 100% of its original resolution will result in pixellation. In a nutshell, any time you scale any raster file larger than 100% of its original size, you will get pixellation. This cannot be avoided. It is the nature of raster images.
5) Vector EPS files CAN be scaled larger than 100% because they are not based on definitive pixels, they are based off [i]vectors[/i]... mathematical points and curves that, when scaled, are re-interpreted to maintain crisp, clean edges. This is the primary benefit of using vector shapes and vector EPS files for logos, they can be scaled smaller and larger over and over again without ever having to worry about the file becoming pixellated... because there are essentially no "pixels" involved.
In my attempt to clarify things, I may be making them more complicated. :( :(