In message <7543587.5hs8tdGgKJ@liber> on Thu, 04 Dec 2014 18:12:07 +0100, 
Tobias Ellinghaus <[email protected]> said:

houz> Am Donnerstag, 4. Dezember 2014, 12:13:13 schrieb Francisco Cribari:
houz> > I usually post my photos in a some photography-related Facebook 
discussion
houz> > groups. One my favorite groups is Black and White Universe:
houz> > https://www.facebook.com/groups/177407189132194 . Their rules include 
the
houz> > following: "Entry photos must be in a standard size of 8'x12' with a
houz> > minimum size of 2000 pixels on the short side and 3000 pixels on the 
longer
houz> > side." Recently, my photos have been excluded from the group, even the 
ones
houz> > that have 3000 pixels on the largest size. I sent the following message 
to
houz> > the group administrator: "Dear Teo: Do you think you can help me 
understand
houz> > the rule? The rule is: "- Entry photos must be in a standard size of 
8'x12'
houz> > with a minimum size of 2000 pixels on the short side and 3000 pixels on 
the
houz> > longer side. It must have NO BORDERS." The photo I posted yesterday had
houz> > 3000 pixels on the largest side and 2000 pixels on the shortest side. 
Why
houz> > was it removed? Was it because of DPI? Do I need to set a DPI value? The
houz> > software I use (Darktable - see http://www.darktable.org) does not 
allow me
houz> > to do that. I don't quite understand what is meant by "standard size of
houz> > 8'x12" for a digital image. It seems that the important bit is 
resolution
houz> 
houz> Exactly, the resolution (in pixel²) is the important part, the inch size 
houz> (which is equivalent to a set PPI value) is meaningless. However, you can 
tell 
houz> darktable to set a specific PPI value for exported images. By default it 
is 
houz> using 300 PPI which would result in less than 8x12. To get the required 
houz> conversion 2k pixel == 8" and 3k pixel == 12" you want 250 PPI. If you 
are 
houz> running either one of the recent release candidates or a git compile you 
can 
houz> set it in ~/.config/darktable/darktablerc, the key is metadata/resolution.
houz> 
houz> [...]
houz> 
houz> > Best, Francisco
houz> 
houz> Tobias
houz> 
houz> PS: I assumed that you meant inches and not feet.

Another solution is to use ImageMagick on the exported image, as follows:

convert -units PixelsPerInch input.jpg -density 250 output.jpg

(replace input.jpg with your exported image and output.jpg with
some suitable name)

-- 
Richard Levitte                         [email protected]
                                        http://richard.levitte.org/

"Life is a tremendous celebration - and I'm invited!"
-- from a friend's blog, translated from Swedish

------------------------------------------------------------------------------
Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
from Actuate! Instantly Supercharge Your Business Reports and Dashboards
with Interactivity, Sharing, Native Excel Exports, App Integration & more
Get technology previously reserved for billion-dollar corporations, FREE
http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk
_______________________________________________
Darktable-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/darktable-users

Reply via email to