Need Help Do you loose quality when scaling raster image in Illustrator

If by "quality" you mean "image resolution", then only if you output in a lower (than the image's native pixel size) bitmap format.

 

Any raster image will loose quality when you expand it...

 

If you’re exporting it at 1/20 then scaling in your rip, then it will likely look horrible.

 

No, you will not lose resolution. Check linked or embedded images with the Document Info palette to become clear.

 

If you're saving as a pdf, go to compression tab, then select do not downsample on all 3. This will keep the images at full resolution.

 

If you take 100dpi image in Illustrator and scale it down by 20x, the image is now 2000dpi. Now if you take that 2000dpi and print it while scaling it 20x, it will most likely look worse than if you scaled everything back up to 20x and then printed.

 

Scaling it 20x in your RIP will change the resolution from 2000ppi back to 100ppi. It should be no different from scaling back up 20x before loading into your RIP, unless the people who designed your RIP software are complete idiots.

 

Correct me if I'm wrong.. But illustrator doesn't alter the image at all. It embeds the original image... Or links to the original image if your not embedding. So resizing won't affect it at all.

IE: if you have a 500mb 10 ft image... Then shrink that image to 1".... Illustrator doesn't actually change the image, and when you save the file it'll still be a 500mb file.. So long as you don't use compression or tell illustrator to downsize the file.

Now if you have a 10" file and want to make it a 50" file... You'll get better quality using photoshop / on1 resize due to its "smart pixel adding" Alligrotham.

But in your case, your image quality will be the exact same as your original image.