X-Authentication-Warning: delorie.com: mail set sender to geda-user-bounces using -f X-Recipient: geda-user AT delorie DOT com Message-ID: <5166FDF4.2090001@buffalo.edu> Date: Thu, 11 Apr 2013 14:16:20 -0400 From: "Stephen R. Besch" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130221 Thunderbird/17.0.3 MIME-Version: 1.0 To: geda-user AT delorie DOT com Subject: [geda-user] Printer Calibration Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-PM-EL-Spam-Prob: : 8% Reply-To: geda-user AT delorie DOT com If anyone has tried to run a printer calibration in PCB and been exceedingly confused by the so-called "Instructions", then I suspect you are not alone. You are asked to measure one of the horizontal or vertical lines, however, that is not exactly true. First, these are not separate lines, they are segments of a single line on each axis. You can only measure one of the line segments that are bounded at each end by a grayed in semi-circle. And then, you can't measure any of these either. Another "sucker punch" is the "large box", which you can't measure at all if you want the calibration to work. Oddly, this is the only box for which dimensions are given. The remaining dimensions and how they are laid out on the sheet you have to search for elsewhere. After studying the code, here's what I believe should be given as instructions (based on most recent code built from source): Run Calibrate Printer from the file menu. This will print a calibration page. When asked for scale factors, leave the default values (1.000 on both X and Y). Retrieve the printed page and note that in the lower left hand corner there are 2 gray semi-circles, one facing up and one facing right. These are the base points for all measurements. Along the Horizontal (X) there are 3 additional semi-circles, all facing to the left. Along the Vertical (Y) there are also three semi-circles, all facing down. Measurements are made between the flat faces of these semi-circles. Select a suitable pair of semi-circles on X and measure between the faces. One of the pair MUST BE THE RIGHT FACING SEMI-CIRCLE the other can be any one of the 3 left facing semi-circles. The nominal values for the 3 possible pairings on X are 4 in, 15 cm and 7.5 in. Then select a suitable pair of semi-circles on Y (remember, one of these must be the UP facing semi-circle) and measure between these faces. Nominal spacings on Y are 4 in, 20 cm and 10 in. Once you have the X and Y measurements, you need to run the calibration again. When asked for the scale factors you may either 1) calculate the scale factor (the ratio of the segment's nominal length to the actual measured length) on each axis (X and Y) and enter these, or 2) simply enter your measurements and let the program calculate the scale factors for you. In the second case, the program will select Nominal lengths that are closest to the measurements you entered. This will only work if the measured values are not too far off, which should almost always be the case. If your values are way off, then you will need to calculate the ratios yourself. -- fictio cedit veritati