450nm Creality Laser won't engrave correctly

[pepito84 (Peter Brem)]

Hi folks,

I’m really new to all that laser stuff and I have the most hobby setup you can imagine:
Ender 3 Pro + Creality 0.5w Laser engraver.

So I tried many different software and Lightburn is imho most comfortable one! So I decided to post my issue here.
I try to engrave an image of my son. But all outcome till now is following:

A kind of an noise pattern.

In lightburn under preview I can see a fairly nice picture.

Do have someone any clue what it can be?
Is it just my hardware which is not able keep up?

Thanks a lot in advance!

[pepito84 (Peter Brem)]

Hmmm… perhaps it has something to do with the pwm mode. I will change it in the firmware to FAST_PWM_FAN. Let’s see what happen.

[pepito84 (Peter Brem)]

It’s getting better!
Propably that’s max I can get out of it.

In Marlin under configuration_adh.h there is a option called #define LASER_SYNCHRONOUS_M106_M107.
With this I achieved above result.

[pepito84 (Peter Brem)]

@anon88048707
Thanks for your feedback!

Yes, I tried with “adjust image”. Funny is that all my changes of gamma, contrast and brightness hadn’t any effect.
I already “optimized” this image with GIMP. Means indexed colors (1bit) and so on. Maybe thats why my changes hadn’t any effect on the image.
I will try my best to redo with different options. This was made with option grayscale next time i will try it with your mentioned and other options.

Have a nice weekend!

[pepito84 (Peter Brem)]

yes, i will stay at round about 300 dpi.