grid patter with a laser

[intaglio]

hi im new to the laser community but i am very interested in finding a laser pointer that projects a grid, i work with visual fx and green screen and i always have to use tape on the wall to create a grid that helps me in the compositing of the shot later in post production and also with the camera tracking, thats a time consuming task and i would like to know if there is a laser , (green laser) that can be used to project the grid, also i would like to be able to adjust the grid distortion in situations where im no able to project directly from the front. and the PERFECT LASER would be one that besides of projecting also measure the distance and angle.. i think if someone here has the technical skill to create that i would appreciate and pay for it.. anyway i found a level laser that measurer angle and distance i just need one that projects the grid


thanks

 

[HIMNL9]

There are already camera units that incorporate lasers for targeting and distance / dimensional evaluation (with a pc and a specific program, ofcourse), but first, usually are professional units for underwater use, and second, costs an eye and a lung (the cheaper ones )

They use six independent lasers drived in scan sequence, 3 aligned with the camera axis, and 3 diagonals, with a fixed angle, and the software calculate the distance of the diagonal dots from the distance of the parallel ones, and give you the distance and estimated dimension of the target from the image on the monitor.

This for the measure part ..... for the grid part, i think that you need a scanner, cause any simple crosslens and diffraction grating cannot be adjusted as you want, where instead a scanner can be programmed for project a definite image that can be also scaled and distorted, if needed.

 

[pwnstar]

I think a simple laser and diffraction grating would be good for him because for what he is using it for, a scanner is wayy to expencive and probably out of his price range. A laser and defraction grating will cost him around 60$ and maybe alittle bit more if he wanted to buy a tripod to hold the laser.

To adjust the size you just move the laser closer or further away. But there will be distortion unless you project from the front.

 

[HIMNL9]

Yes, i was speaking about the scanner just cause he asked for the possibility to correct distortions.

 

[pwnstar]

Oh I see, lol read it wrong.

 

[nikokapo]

You can always use one of those red modules with a cross diffraction grating and replace the red with a green so the cross will repeat itself all over the wall (or just get many reds with the cross).
You can find them on dealextreme.com

 

[intaglio]

hi, well for the measuring part i found a solution with a laser level i found, for the grid i was looking, as pwnstar said , with some optics.. i think with some mirrors ect i would be able to correctly project the dots i need, for the measure i realy use softwares that can track the camera movement and can give the information i need what i realy need for that sofware are good tracking points in the image.. the setup i found interesting was the laseglow brightline laser from another post in this website.. i dont know how safe is the laser with humen skin and soft materilas cose i dont a want laser that burns anything .. for example skin or something like that, not eye of course. and that the diffraction i found needs space to make it wide enough.. is posible to use some kind of optics that widen the laser bean like a the zoom in the camera.

i think im going to get the brightline and some difraction i found in novalasers
what do you think?


ps: pwnstar i love your display picture... hehe that exactly what i need a fan that diffract the laser bean.. jijii
thanks

 

[intaglio]

and another problem is the time the laser has to stay working, anything that is portable is not usable for me .. i need something i can use for hours.. not minutes.. with that i mean something that doesn't use battery and can hold the temperature and the working time..

 

[pwnstar]

lol thanks! Hm, I'm not sure if you can focus the diffraction grating with a lens or not, but that would be a good idea if you can. You can use more powerful lasers because by the time the beam goes through the diffraction grating and splits into a bunch of separate dots it will loose a lot of power. Certainly don't worry about your skin, it wont be focused enough to burn anything; maybe just worry about your eyes.
DG Matrix - Optics - Novalasers Inc.

I think these can be on for a long time but im not sure if you are in the US. If you are you may not be able to order from there.
DealExtreme: $84.12 Genuine New Wish 5V Green Stage Laser Module (50mW/100mW)
DealExtreme: $57.20 35mW Green Laser Module (5V Input)

 

[intaglio]

thanks thats a releaf couse is importan for me it to be safe for everybody working in the set. thanks for the dg matrix tip

 

[HIMNL9]

For the long period working, i suggest you to get a lab style module, that usually are also sold with the AC power supply..... like this offer from aixiz, as example

532nm 50mw adj power laser TTL AC 90-240VAC - eBay (item 360174356175 end time Aug-05-09 00:25:24 PDT)

or, if you buy a normal module, to build a "labby style" heatsink system.

For the power control, that module as example have also the possibility to regulate it lower, on the PSU board, so you can trim it for the power that you need, without risks.

 

[Alexizupinhea]

http://laserpointerforums.com/f39/fs-cheap-diffraction-grating-glasses-3-a-41855.html these will give the exact same grid as the one pwnstar linked, and it's MUCH cheaper and should work fine.