(11-22-2016, 05:49 PM)kayeng Wrote: Thanks a lot guys! I'm starting to understand.
It's actually a 3-fold flyer. When you fold it, it's still big, but it's still considered a flyer where I live. =)
I tried the 5100 x 3300 size, with 300 ppi. Without changing the resolution (72 ppi) of File-02, I copied a layer from File-02 onto the new image (300 ppi), and then resized (made it smaller) as desired. The small image is still sharp! Or at least much sharper than before.
So now I would just like to ask you guys if it was correct to not change anything in File-02 before I copied the layer onto the new image (300ppi). That's what I did and it looks ok. Definitely better than before.
Also, what's better, sinc or cubic? I've read in one website that sinc is better, but another website says cubic is better.
It is better because your 316 x 153 pix thumbnail @ 72 ppi scales to 1317 x 637 pix @ 300 ppi.
A comparison original on left, scaled images on right. Still a little stepping on (3).
There are a couple of tweaks you could try before adding the layer
As Kevin suggested, scale it down in 2 or 3 stages,
or
Use a pre-blur before scaling. 2580 -> 1317 is 53% so use a gaussian blur of 2, then scale down.
Which scaling algorithm to use? I use sinc.