Cheap "Scanners"

[twelti]

I found a link in another thread here with Chinese suppliers, and found this cheap "scanner' (what they are calling galvanometers I guess):

http://goldenstarlaser.com/index.php?route=product/product&path=96_97&product_id=256

The cheapest one is $40 (?!?) That can't be right, though the pic does show what looks like galvos and controller board. Doesn't htat seem too cheap?

 

[Immo1282]

Seems a little cheap maybe - but with anything bought from unknown chinese suppliers - buyer beware.

There's no laser - so it might be cheap - but it's definitely in the realm of plausible rather than nonsense...

 

[diachi]

Seems a little cheap maybe - but with anything bought from unknown chinese suppliers - buyer beware.

There's no laser - so it might be cheap - but it's definitely in the realm of plausible rather than nonsense...

Goldenstar are known, maybe not here seeing as not many people here have projectors, but they're fairly well known for projectors/projector parts. They've been around for a fairly long time.

$40 for 15kpps scanners is cheap, but not unbelievably so. 15k is slow. They'll struggle with more than basic graphics.

 

[twelti]

ahh, that is the kicker then, response time. They do have several models up to a couple hundred dollars so that is nice. Heck though, for $40 just to play with, could be fun!

 

[diachi]

ahh, that is the kicker then, response time. They do have several models up to a couple hundred dollars so that is nice. Heck though, for $40 just to play with, could be fun!

They'll do the job for basic beam shows but you'll get flicker with any sort of complicated graphics or wide scan angles. 20k is the lowest I'd go for graphics and even that isn't great. Ideally you'd want to aim for 30-40k for graphics stuff

 

[twelti]

They have one for $100 that is 30k, and +/- 15 degree. Tempting!

 

[Benm]

This $40 one is only 15k at 15 degrees, so it's a very slow scanner indeed!

It is -very- cheap though if it's the real deal, and if you just want to play with it for a bit i think it would make a decent kit to test the waters a bit. There seem to be NO adjustment pots on the driver board for this cheapest version though, so any fault compensation would have be done in software. On the $100, 30k model all adjustments seam to be available on the driver board.

I would not expect the $40 set to be able to do any animation or such, but it could create nice effects like tunnels or planes at a very low price point.

It also says it's including a power supply, but i don't see that anywhere in the pictures. It may not come with a mains power supply at all and you'd need to get a +/- 24V mains supply yourself. Those aren't that expensive and can be re-used for other projects easily, but it's another factor consider.

If it comes for $40 shipped and works it'd consider it a fun unit to start out with. It will not run amazing beamshows or anything like that, but could still pull off a pretty decent show in a disco environment when used with the proper lasers. Word of warning on that though: these things are not that easy to build, especially when you want something like RGB projection. In such cases the other components will cost far far more than the $40 for this 'scanner' unit, but if you just want something entertaining to look at, probably with a single color from a cheap laser, it's worth considering.

 

[twelti]

I have purchased an RGB module from Banggood, also on the cheap. I was thinking maybe the $100 scanner (which does show a power supply) and the Banggod RGB could be fun. I have a sound card already. I was thinking maybe to try to make my own "software". I am familiar with several high level platforms (which I use for audio purposes). I was thinking that would be more fun. I mean, I could get some dedicated laser software, but it's too easy! Or maybe I'd find even that harder than I thought. Probably.

 

[Benm]

At least try with proven software so you can see if you hardware is actually working well.

The hardware part of it doesn't have to be that complex - you can use opamps to translate the output of a multi-channel soundcard to ILDA levels for both position and brightness control with compliant galvo's and lasers.

The upside of it is that most off the shelve hardware is more than good enough to do this: generic opamps have no problem dealing with the required gain/bandwidth product or slew rate, and the sound cards are fairly capable as well. You'd need 5 channels, but many have more which you can leave unused. One issue could be sample rate: 48 kHz is on the low side to drive a projector, but many usb sound cards offer higher rates (96 kHz would be fine, 192 kHz is not even that uncommon).

 

[twelti]

I have an 8 ch 96kHz capable sound card so no issue there. yes, maybe some inexpensive sw to test it would make sense.

 

[hakzaw1]

Sorry if I missed this but...did not wait for link to dnwld..
perhaps they come w/o PS? -- so $40 plus PS cost

edit
PS is included but as Ben wrote 15kpps is slow- OK for some beam shows but abstracts animations etc may not look good.
@OP make a simple Lumia for that RGB. make so you can swap it out.

BTW BEFORE you send away $$ --there are two ways to set these up.. one right handed --the other left-handed..
So you enclosure's opening needs to be where the scanners will be and the galvo engines y/x need to match.
Only know of one brand that has 'both way' scanner mounts. (irrc Sats. )

good luck and we want lots of pics!!

 

[twelti]

If you go up to the $100 version, it shows a power supply. That one is also a 30 k version, probably the one to go with for a cheap starter (?)

 

[green lasers rock]

I consider 25-30k the minimum for any real graphics IMHO. As Diachi mentioned, Goldenstar is rather infamous in the projector world. I have seen numerous threads regarding the AL15K scanners on another certain laser forum. I seem to recall someone claiming they had a set and only got around 8k or so, but i'm not sure. 8K would only be enough for the simplest beam shows, but even simple liquid skies can be quite impressive. As for the "30k" set, all of the AL scanners tend to have a bad rep and I think you'd be lucky to get 25k at 8 degrees. On the flip side, the DT scanners which Goldenstar also sells are widely used, but at more than double the price, it may not be worth it to you. I know that the DT 40s can do a solid 35K at 8 degrees, but i'm not sure about the 30s. If your simply looking to throw together a rig with an audio card DAC, you probably couldn't go wrong with the AL30s. Just don't come in with unrealistic expectations. Thought I'd also mention that if you look around, you may be able to find a set of true 30k scanners used for $100. DTs may also be your best bet in that regard.