Re: [Gimp-user] Borderless photo not correct

[Gary Aitken <gimp dreamchaser org>]

On 01/10/15 13:32, Mark Bourne wrote:
> Tikiman wrote:
> > Hello to all I am a very new user of Linux and the supplied Gimp
> > program. I tried out my printer (Canon Pixma MG5550) in gthumb and
> > Gimp by printing a borderless 6 x 4 photo. I changed the settings
> > in the print tab to read Glossy photo paper and size as borderless
> > 6 x 4 and also the orientation to suit my needs. The photo printed
> > okay BUT there is a small border about 8mm at the top and 2mm at
> > the bottom of the photo.in portrait style. This did not happen when
> > I had Win XP and Arcsoft software and after checking as much as I
> > can I am unable to locate a solution. Does anyone know why this
> > happens and can it be resolved?. I would appreciate some help with
> > this please. many thanks Tikiman
>
> What are the dimensions of the photo? Many digital cameras produce
> images with a 4:3 ratio, which doesn't exactly fit the 3:2 ratio of
> 6x4 paper. Either a border has to be left along the shorter edges or
> part of the image has to be cropped from the longer edges.

Actually, there is a third option, and I think it is the default for 
some windows applications: do an asymmetrical resize to fill the
paper.  You get a distorted image but apparently a lot of people don't
notice.  (I'm not sure if it's the default or not; I normally don't
run win anything.)  

> I'm not sure if that decision would be down to the software or
> printer driver, but either way it's possible that GIMP / Linux driver
> takes the former option so that no part of the image is lost, while
> Arcsoft / Windows driver may have taken the latter option to produce
> a truly borderless print at the expense of losing part of the image.

I believe it's an option somewhere in the print configuration,
something like "resize image to fill paper" (printer driver)

> Try cropping the photo in GIMP so that it does have a 3:2 ratio
> before printing. Also check File > Page Setup in GIMP to ensure it is
> not adding margins. If that still leaves a border, I suspect it would
> be more down to the printer or driver rather than GIMP.

Additional note:  If you're printing *with* a border, you want to resize
to whatever the final aspect ratio will be, and that will depend on the
actual border size.  In this case the aspect ratio of the image will not 
be the same as the aspect ratio of the paper.  For example, I print using
the smallest border for my epson printer, which is 3mm:
  4" = 101.6mm                 101.6 - (2*3mm) = 95.6mm
  6" = 152.4mm                 152.4 - (2*3mm) = 146.4mm
  152.4/101.6 = 3/2 = 1.5      146.4/95.6 = 1.53

Gary