Using LSX to check the tuning of your galvos

[_LSX_]

LSX helps you check the tuning of your scanners and lasers by displaying test patterns which test different aspects of 'what it takes' to display graphics properly.

To begin, make sure your DAC is connected to your computer and projector. Run LSX and click the 'Edit Scanning Optimizations' button on the upper toolbar. It has an icon that looks like a speedometer. This opens the Optimization page of the settings dialog of LSX. There are a lot of settings, but don't let that worry you, we won't be dealing with those right away. Just focus on two things right now: the PointRate setting over on the right and the TestFrames box on the left.

You want to start by setting the PointRate to the rate that your scanners are advertised as being able to achieve. Then in the TestFrames box, select ILDA Test Frame and click 'Display Test Frame'. Your projector will now be displaying the ILDA test frame, assuming your DAC was found by LSX.

TestFrame as it looks in the preview window.

testframe.png (6.06 KiB) Viewed 23159 times

The first thing to notice is the way two shapes are being scanned in the very inner center of the pattern: the inner circle and the inner square. A properly tuned scanner pair will display a perfectly round circle with the circle edges just touching the flat edges of the square (not its corners, as it appears in the preview), when the central ILDA test pattern is scanned at the manufacturer's scan angle (commonly 8 degrees).

If the circle is not round, but slanted oval, it means the scanners are tuned to slightly different frequencies, or your DAC (if it is a sound card DAC) is producing x/y points with a time skew between them.

If the circle is smaller and completely inside the square, it means that the point rate you have selected is too fast for the scanners to draw. The scanners either need to be tuned, or you need to reduce the PointRate setting in the Optimization dialog. Reduce the PointRate by sliding to a lower point rate (or using the arrows), then toggling 'Display Test Frame' off, then on again.

When you have found a point rate that your scanners can draw the circle and square properly, you have found their current tuning kpps rate. Click 'Save ScanParameter for autoload' to save your kpps setting for future use in shows that use the 'Default' named Optimization set.

[dzodzo]

Greetings, i allowed myself to post here optimization settings for Kvant Spectrum projector with CT6215 scanners. This is set to 35k as that was the highest scanners did with plausible results. At 50k the outer square started to lose sharpness at edges.



In case picture doesn't work, try to get the preset here:

[dzodzo]

I created another preset for Laserworld RGY projector with LW-50k scanners. This is set to 20k as more than that the output started to seem deformed. Note that these galvos haven't been tuned so it may perform better on other projectors.

http://gallery.kirril.com/images/0001/1326828258911.jpg

The preset can be found here: http://furikuri.no-ip.org/Private/laser ... LW-50k.RSP

[_LSX_]

Hi, it's good you've found the settings that work for your scanners. Just an FYI, the test frame is designed to be scanned without optimization, so only the scan rate adjustment on the optimization page has an effect when you are viewing the test frame. To tune up optimization blanking, you can create or load any other frame into the catalog and use that.

I've attached some setup instructions from a user (thank you) that offered them to help people adjust their settings.

Also I have in the plans a settings wizard that will help guide you through the scanner optimization for your scanset. But in the meantime have a look a the attachment.

[dzodzo]

drlava, can i use the information posted here in the LSX manual? so that i don't write something that's already been done, i can add pictures with explanations as well to make it easier for the user to understand how it works

also any progress on code? the optimization wizard i mean...

thanks for reply