Re: [Gimp-user] how to change image resolution without effecting scale within the image itself using gimp as in retaining the roundness of the moon

[Steve Kinney <admin pilobilus net>]

On 03/24/2017 04:03 PM, fenpeppertree wrote:
> I have an image I downloaded from the Internet that has an image size of 1024 x
> 768. I would like to use this image as a desktop background at a resolution of
> 1920 x 1080.
>
> This is a Halloween image, and has a moon within the image. When scaling the
> image from 1024 x 768 to 1920 x 1080, the moon becomes stretched and no longer
> appears circular.
>
> Is there a way to increase the image size and alter the resolution without
> effecting the image content scale (the moon retaining a perfect circular shape)?

Not if you are changing the proportions of the image as a whole:  The
moon will change to conform to the new aspect ratio.  But you can scale
the source image to your desired height or width, keeping the original
aspect ratio, then crop the image to the desired width or height.  Try
it both ways (scale the smaller image to 1920 width, and see if it can
be cropped to suit your purpose.

Another thing to try:  Use the Tool Options dialog to manually set
"Allow growing." Manually set the height and width of your crop
selection to the desired size, which will extend beyond the original
(1024 x 768) image boundary.  Then set Fixed Aspect ratio in the crop
tool dialog.  Now you can play with the crop area freely by clicking and
dragging the corners and edges, to make it fit around whatever parts of
the original image you want to keep.  Crop the image, and scale it up to
your target dimensions.

:o)