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Re: Graphics export to BMP and JPEG

• To: mathgroup at smc.vnet.net
• Subject: [mg82649] Re: Graphics export to BMP and JPEG
• From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
• Date: Sat, 27 Oct 2007 06:01:28 -0400 (EDT)
• References: <ffsdbd$ojr$1@smc.vnet.net>

Hi,

why, please tell me WHY, *W_H_Y* do you export a bitmap
when you have a vector graphic ?
For an ordianry Plot[] result the vector graphic
has a smaller file size can printed in any resolution.

It is hopeless to make a bitmap because your screen has
ca 72 dpi, a medium quality printer 600 dpi and your eye
2200 dpi .. you will never have the right size/resolution.

Regards
   Jens

Hannes Kessler wrote:
> Hello all,
> 
> what options are recommended for
> Export["image.bmp",_Graphics,ImageSize->..,ImageResolution->..], also
> for image.jpg, image.tiff in order to get image files of the same
> quality as right mouse clicking the image in the notebook and copying
> as a bitmap or metafile? I tried different values of ImageSize-
>> ..,ImageResolution->.. but with quite poor results. The _Graphics
> were ordinary plots created by Plot or ListPlot.
> 
> For example, Export["image.bmp",_Graphics,ImageSize-
>> Large,ImageResolution->72 n] with n=1,2,3,... did not improve the
> image quality with increasing n. I checked with Irfan view that with
> increasing ImageResolution the default print size of the image
> decreased proportionally. In other words, the image resolution at
> constant image size remained always constant (and poor).
> 
> Increasing ImageSize at constant ImageResolution increased
> proportionally both the default print size and the number of pixels as
> one would expect. But artificially exporting the graphics with large
> ImageSize and then sizing down does not help as the text size remains
> constant during the export even when ImageSize increases and thus
> sizing down subsequently would make the text invisible.
> 
> As a side question, what are the default sizes for ImageSize->Large,
> Medium or Small in different situations? Are they documented
> somewhere?
> 
> Thanks in advance,
> Hannes Kessler
> 
>