Jumping into the self-build fray

[Draco]

ok cool, i was thinking of trying spaghetti and a home made sound card DAC but the author of spaghetti has not been replying to my questions, i have laserboy's software but the command interface makes it kinda hard for me to use.
I also e-mailed the company that makes the flex mods to see if the non beam suppression units can be modded at a later date to have that feature if needed, right now the glow is not being a problem, there is only 4 dolor difference, i may try the mod in the future anyway, i am good with a soldering iron, i just wonder if they have a different firmware on the suppression ones

[swamidog]

there is a firmware difference between the two flexmod types. you will not be able to modify them.

ok cool, i was thinking of trying spaghetti and a home made sound card DAC but the author of spaghetti has not been replying to my questions, i have laserboy's software but the command interface makes it kinda hard for me to use.
I also e-mailed the company that makes the flex mods to see if the non beam suppression units can be modded at a later date to have that feature if needed, right now the glow is not being a problem, there is only 4 dolor difference, i may try the mod in the future anyway, i am good with a soldering iron, i just wonder if they have a different firmware on the suppression ones

[Draco]

cool, thank you for the info

[frostypaw]

OK there's a little camera flare spoiling how sharp this is, and you can see some frame-ripping but with successful filtering I've gotten here.

I made a pretty easy pinhole filter with the firm foil lid of a yoghurt drink stretched across the gap in an L bracket. Five pinholes at different heights near where it seemed to be hitting gave me a bit of choice and flexibility so it wasn't too much of a nightmare hand-positioning it. it's proven impossible to get it to a point where it filters every bit of splash out of the beam. As it's moved down-beam the red starts diffracting and flaring before the blue is clipped but since I've found a pinhole camera seller on eBay who's selling sub mm apertures at tiny prices (£2!) I've bought a .4 and .25mm aperture to try with. They're properly cut on 0.1mm brass so we'll see if clean edges help, but positioning is going to be a bitch - will be fun until i assembled a planter's style razor based fixture at least.

Until then it's the cleanest laser I've seen in person even in pitch darkness so I'm happy bring on UKLEM and some proper comparisons with folk who know better!



I seem to have an oddity from my PL450B though - there's in-beam interference I think. Viewed from the right angle the beam is made of a stack of dashes ||||||| like that getting shorter towards the outside. It's now filtered mostly but still curious, unfortunately my other pl450 went to a friend as a pointer... doh.

[djdulux]

Looks very good, looking forward to seeing it at UKLEM....

Dupe...

[dkumpula]

I seem to have an oddity from my PL450B though - there's in-beam interference I think. Viewed from the right angle the beam is made of a stack of dashes ||||||| like that getting shorter towards the outside. It's now filtered mostly but still curious, unfortunately my other pl450 went to a friend as a pointer... doh.

I have seen this previously. I would guess that your diode isn't mounted straight or that your colimation lens is positioned at an angle to your diode. I'd bet you are getting less power out of that diode at the same current as a result of this as well.

Nice job on the attention to the cleanup!

David

[frostypaw]

Ah cheers, that's the confirmation I wanted before taking that apart again. Off-axis makes sense. There's tomorrow's lasery fun sorted gives me a chance to tweak the ratio on the red prisms too, it's slightly off

The clean-up became serious after I used a little dentist's mirror to bounce it the length of the flat - the splatter visible behind the mirror on the wall was huge and while the eye couldn't pick out the pattern as it scanned around cleaning it up has made an improvement like having a higher contrast ratio video projector.

Become quite curious if the lack of eye injuries due to over-spec laser shows might be partially due to this splatter which used to become too bright to look at well before the beam was near my face, possibly giving an extra margin of safety. With the cleaner beam I can get much much closer to the beams before looking upstream is bad, I've scanned myself when I didn't realise I was even near a sheet of light - much less warning. Maybe splatter gives people an extra .025s to blink, would be interesting to try and measure.

Also had fun bouncing a white beam back to the projector with the lid off to see the RGB interference patterns on the wall the gaps are interesting, but I suspect unfillable. Would be good to try with a 650/532/405 mix to see the difference

[frostypaw]

I have seen this previously. I would guess that your diode isn't mounted straight or that your colimation lens is positioned at an angle to your diode.

This was spot on - it was microscopically out, couldn't see it to be sure with the naked eye but at 100x was just not level. Gave it a rough time with the diode press then wasted a few minutes trying to clean the reflection of the diode facet off the coverglass, but all back together now and no more double image or multi-line effect - thanks!

[dkumpula]

Awesome, glad to hear it! I've got a few that I need to adjust myself now that I have a proper set of diode presses.

-David