Hello Jean,
Thank you for your question about generating a high resolution image of the browser for use in your paper. I assume here that you are talking about a track image created by our main browser CGI: http://genome.ucsc.edu/cgi-bin/hgTracks. If so, you can control the width of the image from the browser configuration page, which can be found by clicking the "configure" button below the track image. The height of the image is calculated based on the height of the individual tracks being displayed. As an alternative to right-clicking and saving the image, you can try the PDF/PS output option in the View menu at the top of the hgTracks page. Importing the browser image into your paper from an encapsulated postscript file might give a better result.
You may also be interested in the answer to the following mailing list question: https://groups.google.com/a/soe.ucsc.edu/d/topic/genome/skK5JE8_JJQ/discussion.
I hope this is helpful. If you have any further questions, please reply to gen...@soe.ucsc.edu or genome...@soe.ucsc.edu. Questions sent to those addresses will be archived in publicly-accessible forums for the benefit of other users. If your question contains sensitive data, you may send it instead to genom...@soe.ucsc.edu.
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Jonathan Casper
UCSC Genome Bioinformatics Group
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