ScanPro20 + USB Soundcard + Spaghetti Troubles!

[seanharrison]

I am having some trouble with my ScanPro20's and Soundcard DAC, I there seems to be gaps in the lines

Here is the ILDA Test Pattern from Spaghetti

and also a couple of shots from RockConcert spaghetti show

If you look at the ILDA test pattern it doesnt look too bad, but the square in the center is not joined on the left side....!

Any Idea's ?

Cheers, Sean

[thesk8nmidget]

how far away is your scanner? can you figure out the angle your projecting the test pattern? and at what speed?

it is probably to much for the scanners causing it to overshoot on the square.

as for the lines going to far past the squares in the picture you can adjust the "hold" setting in spaghetti..

try the blanking hold option first and that should get thos lines to go away and the gaps to close.

[DZ]

Not sure why the square isn't coming together properly on the side there. IF the scanners are properly tuned for 20K, then you're scanning a bit too slow, which is why the circle is outside the square. You also need to adjust blanking shift. If you look at the top line that I have circled, then compair it to one of my pics, you'll see that blanking shift should be adjusted.

[buffo]

DZ nailed it. The color shift is wrong. That's why the vertical line on the square isn't meeting at the corner like it should. (It's also why the lines at the top of the pattern are wrong, and why the "ground symbol" at the bottom is shifted to the side.)

The scanners also appear to need a little tuning (or as DZ mentioned, they're running slow), but that's *not* what's causing the problem with the line on the square...

Suggest you contact Gary via his google-group for Spaghetti (or via E-mail) and ask him how to adjust the color speed offset.

Adam

[thesk8nmidget]

as said above you can go into the scanner settings and change the "hold" settings.

it will be the 3 options on the left.

[seanharrison]

DZ nailed it. The color shift is wrong. That's why the vertical line on the square isn't meeting at the corner like it should. (It's also why the lines at the top of the pattern are wrong, and why the "ground symbol" at the bottom is shifted to the side.)

The scanners also appear to need a little tuning (or as DZ mentioned, they're running slow), but that's *not* what's causing the problem with the line on the square...

Suggest you contact Gary via his google-group for Spaghetti (or via E-mail) and ask him how to adjust the color speed offset.

Adam

I have tried re-tuning them, I think i have made things worse to be honist. I followed your guide adam, But i dont think i am getting a clean enough singal from my soundcard DAC, this caused me a few problems during tuning. I think i am gonna have to get a real DAC before i continue.

I am running the scanners at 20k in spaghetti.

as said above you can go into the scanner settings and change the "hold" settings.

it will be the 3 options on the left.

I have tried these setting before and after re-tuning but i they didnt seem to make a difference

[absolom7691]

You could also try running the test pattern through LaserBoy. You will have to turn off the optomization feature. You can change the blanking timing in LaserBoy to match the speed of your scanners. James put it to me like this, and this is your problem, blanking using modulation or a PCAOM is instantanious compared to a moving galvo. The signal to the glavo is instant, but the galvo has to accelerate, slow down, stop and accelerate again. The inertia involved makes the glavos slow compared to TTL or analog modulation or a PCAOM. So you have to dumb down the blanking to the scanners' speed.

[drlava]

I have tried re-tuning them, I think i have made things worse to be honist. I followed your guide adam, But i dont think i am getting a clean enough singal from my soundcard DAC, this caused me a few problems during tuning. I think i am gonna have to get a real DAC before i continue.

I am running the scanners at 20k in spaghetti.

Can you descibe what about the signal isn't 'clean'? I've tuned using sound card DACs before with good results, so don't think it's something with the sound card dac concept that is causing you trouble, maybe there is an issue with your implementation?

[James Lehman]

NOOOOOOOOOOOOO! Don't get a "real" DAC!

You just need to get the timing right!

Do you know about all the stuff in LaserBoy menu 'b' ???

If you option '4' set desired LaserBoy wave sample offsets to something like...

7
7
0
0
0
0

X & Y are logically tied together and set as one value. R, G, B, and I can be set individually.

Then option '5' apply offsets to LaserBoy wave, you will modify whatever wave file you select such that the x and y signals to you scanners will be sent out 7 samples before the color channels.

You might find this to be just what you need!

James.

[seanharrison]

Can you descibe what about the signal isn't 'clean'? I've tuned using sound card DACs before with good results, so don't think it's something with the sound card dac concept that is causing you trouble, maybe there is an issue with your implementation?

The signal seems to drop out sometimes leaving half the image, this sometimes causes the blanking to stop responding. I am thinking this is an issue with the Windows Vista drivers, because it does not seem to do it with XP