It seems with latest update that these two got mixed up. I had a shortcut made so that it would use "scale to frame size" which would size my image to frame size and show it up on effects control to "50" (im using 4k in 1080 seq) Now it seems its the other way around. Is it just me?
Check the Keyboard shorts panel, of course. See what that short is doing at the moment.
Now, personally, I can't really think of when I would want to use 'scale to' ... that rasterizes (computes) the image down to the 1080 size, and any further scaling you do takes that 1080 set of pixels, not the original resolution, to compute the new image. (This is useful say on low-powered computers for playback, as its fewer pixels to compute/display.)
So ... use scale to with a UHD to FHD sequence ("4k" to 1080) ... then zoom in just a little. You are now up-rezzing from a 1080 image to the new image.
I nearly always use "set to frame-size" so Premiere will always calculate from the original pixel resolution.
Sorry i got them mixed up, yes its other way around. I guess where it got reversed was that I had made a shortcut to "Set" to frame size, and after the latest update, the shortcut turned into "Scale". dont know how that happened, but yes i only use that Scaling for better quality and also i am able to adjust after.