Laser scanner software

[persew]

Hi!

Just yesterday i downloaded the DAVID software and made the first test and i'm very impressed. For the first test i used a Logitech Quizkcam Zoom and a 30€ laser level from a commercial center. You can see the results on the attached images.

Next week i want do more test with a Panasonic videocam, but i'm thinking two more alternatives:

1.- Refrigerate the Quickcam CMOS with a Peltier module and a fan unit to decrease the thermal noise.

2.- Put the laser on a vertical rail moved with a steper motor, take photo with my digital camera on each step, make a video with the photos and send it to the DAVID software through a virtual webcam software like Fake Webcam.

I will publish my results here...

[hllrsr]

Persew,
Is that the image straight from David, or has it been processed?
If that is raw, compared to what I get from a mechanical probe, I am very impressed.

I am sure there are better systems/software available, but for freeware software it is impressive.

Methinks we owe the development team a BIG round of thanks..

Iain

Who's still looking for a laser that can give a line thickness of less than 1/8" at 4 foot range....

[greybeard]

I'm also trying the David software using the laser line generator out of my bench drill, and either a low end webcam - SmartCam, or my canon powershot g2, which has a short video mode.
Not getting on too well at the moment, but I will persevere.
I'm going to need help understanding why my cheap webcam works(up to a point) but my high-end camera isn't found by the software, even though I can get a "live" image on the monitor within canon's own software.
John

[greybeard]

Hi Iain.
just read your latest post, so I've checked my drill laser - 0.25" at 4' I'm afraid.

Hi Jerry, I'm going to be split between my own thread and this one, I can see.
But my new thought is could one use a bright light(quartz) illuminating a slit with a decent lens as an alternative to a laser ?

[debogus]

Split cam will make the canon work ( should?)
After playing a day,first a low rez web cam then my sony DV (with split cam)
Each time better results, I went and picked up a Microsoft" life cam vx 6000"
1 meg / video 5 meg still

Wondering about a larger alignment wall ?

[hllrsr]

Hi Iain.
just read your latest post, so I've checked my drill laser - 0.25" at 4' I'm afraid.

--snip--
But my new thought is could one use a bright light(quartz) illuminating a slit with a decent lens as an alternative to a laser ?

At this point, I don't have a laser on hand to try, but I think that may be solved tomorrow, so what would happen if the laser lens was masked? Would it damage anything?
Could a thick mask (heavy tape?) be used to "thin" the line the laser projects?

One problem I can see with masking a quartz lamp, or even a krypton automotive bulb, is the heat generated by the bulb. Quartz gets nasty hot, quickly! I have no print detail on my right index finger or thumb from a 75w QH bulb in a lathe mounted work light. 75w may not sound like much, but when the glass is being heated for an hour or two......OUCH!

---EDIT--- I just re-read my reply and realised something, I am discussing masking the lamp, like the old blackout lamps, while you suggested shining through a screen (no contact)....which is what I believe the Camtronics' system uses. An overhead projector with masking applied to provide a fine, bright, white line. Would this work with the free software?? or does it need the contrast of a colored line? ---EDIT---

BTW, It would appear the answer to my original question would be...save my money, there are decent alternatives to buying the software.

ATB,
Iain

[greybeard]

Iain, what I have in mind is a quartz lamp possibly with a piece of glass rod to give a preliminary concentration of its light onto a glass microscope slide(for example).
The first face to be made translucent - paint/tissue paper/whatever - and the outer face to have two pieces of opaque tape with a 0.004" slit between them. With a decent lens( about 4" focal length), project an image 4' and it ought to give you what you need.
Problems -
1. Is the white light ok for the David software.
I think it is, but if not make the filter red instead of white.
2. there might be diffraction lines with the slit image.
I think the camera settings in the software will enable you to reduce the effect to a point where it doesn't interfere.

I've just thought that an old slide projector,with the "slit" on a slide, might be just the job, but you'd have to mount it on a stand to take the weight ! And I'm not sure if the lamp will be too happy being waggled about.

John

[persew]

Persew,
Is that the image straight from David, or has it been processed?
If that is raw, compared to what I get from a mechanical probe, I am very impressed.

Yes, are raw data but viewed with Meshlab.

[greybeard]

Iain -I've just projected a white line 2-3mm wide about 4' onto a wall. the "slide" in the projector was two pieces of black vinyl tape on the surface of a glass slide - no translucent layer at all.
I've not tried it yet with the David set up as I'm still trying to sort out camera problems.
Sven on the David website said it will work, and awaits my posting when I get to that stage.
Perhaps you can beat me to it as I've just managed to stab my hand with a piece of glass, so I am now going to have a very large drink, and the timetable for this evening is already set out.
So it will be next year before I can proceed !
Regards
John

[hllrsr]

Since we seem to be veering off into the "how to" end, how about we move this discussion to John's thread "3d for Crazies".

Thanks,

Iain

[greybeard]

Iain - your absolutely right. My apologies for rambling on(as usual) and getting off topic. Back to the other thread.

[persew]

Hi!

I continued with the scan tests this week, and i got big improvements.

I tryed to record a scan session with a VHS cam connected to a dvd recorder, convert the dvd to avi and send it to DAVID via SplitCam software. Results are a bit better but is a very large process for the little improvement and i decide no investigate more on this way for now.

Then i back to the webcam method,k but this time mounting the laser on a tripod with the Z axis moved with a crank and i expended more time adjusting the camera and the object. The results on the attachment.

Next step is study the SCANALYZE software for align and merge scans...