Re: [Gimp-user] Scaling up photo

[Liam R E Quin <liam holoweb net>]

On Wed, 2019-03-20 at 17:57 -0400, Rick Strong wrote:
> Does anyone know of really good software for scaling up an 8x12 inch,
> 300 pxi photo to, say, 16x20 or 20x24 inches or larger? Will GIMP do
> that? 

At 10 to 12 feet, 144dpi will be fine. Fine Art magazines and books
rarely go over 150 lines per inch in a dot screen, so although 300dpi
is recommended, 150 is fine, as long as you don't have text at small
sizes.

So, 8x12inch at 300dpi is 16x24inch at 150dpi.

Now, newspapers use 75 or 72dpi screens generally. So try looking at a
newspaper photograph from ten feet away and see if you're OK with the
quality.

If so, your image is good for 32x48inches unchanged (or just changing
the image’s Print Size).

If you're sending this out to a print shop, ask what resolution they
need. If they insist on 300dpi, you can use gimp to scale it up; the
results will not generally be as good with Fractal, though. You might
also be able to use the liquid rescale / resynthesizr plugin to get
better quality, because you're asking gimp to invent detail.

Liam


-- 
Liam Quin, https://www.delightfulcomputing.com/
Available for XML/Document/Information Architecture/XSLT/
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