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Video P*r*o*b*i*n*g / Re: Photos of webcam scanner. ( no laughing.. :) )
« on: April 10, 2008, 09:40:58 PM »
Hey All,
I too have been spending some time of late trying to figure out the whole Webcam Laser Video probing process. I must admit that with no prior digitizing/probing experience combined with the relative infancy state that the Plug in and viewer are in it has been most challenging.
I don’t mean to “Hijack” this thread but since it seems it is a popular ‘view’ it seemed the appropriate place to do it.
Got my laser (the cheapie $4.50 one that was recommended on the other thread). It says it’s a 3.2VDC but, my Power supply is only 3VDC. All seems OK- I have a red line so I guess it’s OKee Dokee. If not could someone let me know?
The first camera I tried was a nice Logitech. I think it cost me around $60. With the default settings that the fancy schmancy driver software uses (i.e. auto exposure/ auto white balance, color correction, anti flicker, etc) I could not get a square wave to save my life. After monkey-ing around with manual settings for about an hour I finally managed to get something that resembled a square wave.
Scans with this Logitech camera didn’t yield any encouraging results. Until, I changed the “Ignore less than parameter” to -100 (as Art had suggested to ‘aolshove’ in the alpha release of point generator thread). While I was able to FINALLY get data into the computer and view it in Mach Cloud-(WHOOOOO HOOOOO!!!))
, I had points on the Zero plane. I agree with Art, those points are annoying.
So, I got another myself another Webcam- Cheap P.O.S. $15 version (I think they had it at Big Lots-LOL). Without any fancy settings software, the camera worked great right out of the box. Scans were the same with the lights on or off. This was a HUGE step forward. So, I would have to say that the type of camera and driver software that you use seems to play a large (if not huge) role in the acquisition of data. It would be cool if the Logitech (or any camera) settings utility actually had some psychedelic color/intensity/saturations effects filter knobs that would allow you to tweak up the laser/square wave gain but alas, this is but a dream (for now).
So, with the camera out of the way (for a moment), there are those mysterious settings on the Plug-in. Just what does all of that stuff do? Cube size is obvious. My cube is 1.5” so I set it for 1.50. But what is Cam FOV. OK, I know it stands for Field of view but, expressed in what units? Inches/Degrees. Is the field horizontal, vertical or diagonal? I have tried messing around with it (FOV), to get it to change the height value to equal the distance from the camera to the TOP of the cube. Is that right? Or, is it to the bottom of the cube otherwise known as the table surface/zero point? Hmmmmm,
which is it?
On the subject of alignment and such. I was wondering where the best place for my Z axis/camera angle? High Z hovering directly above my subject matter or Lower and angled 45 Deg downward. Another Hmmmmm? Have not yet been able to experiment with this yet as my current spring clamp/electrical tape camera set up doesn’t give a lot of pan/tilt flexibility in this area
. I’m gonna work on that and get back to ya. Perhaps others can offer some insight here?
I set my feed rate @ 75 (IPM). Default comes up @ 500. That seemed kind of high to me but then I though maybe that’s how Art had it set for his machine running in MM. After a few scans I started playing with feed rate and it doesn’t seem to change things that much- either how fast the machine scans- nor the quality of the scans. It does effect how fast the machine Re-Zeros itself after the scan is finished though. Not really sure about the feed rate will help/hurt. Does a slower feed rate yield better results (i.e. smoother scans) or just take more time? Yet another Hmmmmm.
I stepped the Y at .039 (Inches). Default I think = 1 (again probably 1mm-but that’s on that ‘crazy’ other measurement system so I use 'our' systems convenient
# .04”. Starting out small I’ve been scanning a 4” to 10” area. The scans usually take about 15-30 seconds to complete. At first I scanned only in Y then I tried scanning in both Y AND X but when I open the clouds in MachCloud, I get a message that says, “Use left/right arrows to register the striped cloud, press enter when done”. I press the arrow keys but nothing happens, the mouse doesn’t seem to do anything- so, what’s a guy to do? I press ‘Enter’ (sometimes multiple times and more points keep appearing. The cloud is there but I’m left wondering if I missed something or is that feature just not enabled yet?
I have tried scanning a bunch of different things and had varied results. Some things that I thought looked great during the scan, don’t generate a good point cloud at all. Others that I thought wouldn’t scan well, actually produce some good results. It’s kinda weird and I wish I could figure it all out.
I played around with the “Ignore” setting a little but I don’t really understand what it is that I am ignoring. Is this telling the computer if something is lower than this value then it won’t record it? For example, if I had a 2” cube on my table and said Ignore 1.0 then would I get a scan of just the top 1” of my cube? I’m not clear on this one- anyone have the answer on how this works?
Here are 3 scans that I did only in the Y axis. Sorry it's nothing too exciting, I'll try to find some more interesting subject matter. I would rate the scans “OK” but I think that they are no where near the resolution that Art was able to get on the scans of his hands.
1. The trpzd woodblock was 1st. Not too shabby but the points are all really close to each other almost forming a line. When I try to mesh/surface the surface is wavy and smooth and flat like the original block. Is this the scan or something you tweak in Rhino?
2. Since the Vacuum nozzle was black, I thought might not scan well. I was happily surprised to bring up the point cloud. It seems to lack Z depth, as if something got cutoff/pruned down there. Maybe this is another setting/camera angle/height thing? Any advice on this anyone?
3. Finally the wedge of foam. After a few adjustments of the “Ignore Z” settings I was able to get it. Again, this one seems like I have too many points lined up in rows and it gives a distorted wavy look to the cloud even though the subject is flat and smooth.
I suppose spending a little time using the touch probe method of digitizing would be enlightening and also provide some basis of speed/quality comparison. The MACH3/laser webcam digitizing concept is so promising! I hope that its development matures rapidly as I think MANY would benefit from integrating this process.
I feel I am close but it seems my lack of experience is keeping me from crossing that frontier into the land of clear scans. Arrrg-I love this plugin! I hate this plugin! Maybe some of the dudes who have some more experience, knowledge or even luck would chime it would help me to lose the “hate” part. I have more questions and comments but I think this is a good place to stop for now.
Thanks and Regards,
Sid
I too have been spending some time of late trying to figure out the whole Webcam Laser Video probing process. I must admit that with no prior digitizing/probing experience combined with the relative infancy state that the Plug in and viewer are in it has been most challenging.
I don’t mean to “Hijack” this thread but since it seems it is a popular ‘view’ it seemed the appropriate place to do it.
Got my laser (the cheapie $4.50 one that was recommended on the other thread). It says it’s a 3.2VDC but, my Power supply is only 3VDC. All seems OK- I have a red line so I guess it’s OKee Dokee. If not could someone let me know?
The first camera I tried was a nice Logitech. I think it cost me around $60. With the default settings that the fancy schmancy driver software uses (i.e. auto exposure/ auto white balance, color correction, anti flicker, etc) I could not get a square wave to save my life. After monkey-ing around with manual settings for about an hour I finally managed to get something that resembled a square wave.
Scans with this Logitech camera didn’t yield any encouraging results. Until, I changed the “Ignore less than parameter” to -100 (as Art had suggested to ‘aolshove’ in the alpha release of point generator thread). While I was able to FINALLY get data into the computer and view it in Mach Cloud-(WHOOOOO HOOOOO!!!))
, I had points on the Zero plane. I agree with Art, those points are annoying. So, I got another myself another Webcam- Cheap P.O.S. $15 version (I think they had it at Big Lots-LOL). Without any fancy settings software, the camera worked great right out of the box. Scans were the same with the lights on or off. This was a HUGE step forward. So, I would have to say that the type of camera and driver software that you use seems to play a large (if not huge) role in the acquisition of data. It would be cool if the Logitech (or any camera) settings utility actually had some psychedelic color/intensity/saturations effects filter knobs that would allow you to tweak up the laser/square wave gain but alas, this is but a dream (for now).
So, with the camera out of the way (for a moment), there are those mysterious settings on the Plug-in. Just what does all of that stuff do? Cube size is obvious. My cube is 1.5” so I set it for 1.50. But what is Cam FOV. OK, I know it stands for Field of view but, expressed in what units? Inches/Degrees. Is the field horizontal, vertical or diagonal? I have tried messing around with it (FOV), to get it to change the height value to equal the distance from the camera to the TOP of the cube. Is that right? Or, is it to the bottom of the cube otherwise known as the table surface/zero point? Hmmmmm,
which is it?On the subject of alignment and such. I was wondering where the best place for my Z axis/camera angle? High Z hovering directly above my subject matter or Lower and angled 45 Deg downward. Another Hmmmmm? Have not yet been able to experiment with this yet as my current spring clamp/electrical tape camera set up doesn’t give a lot of pan/tilt flexibility in this area
. I’m gonna work on that and get back to ya. Perhaps others can offer some insight here?I set my feed rate @ 75 (IPM). Default comes up @ 500. That seemed kind of high to me but then I though maybe that’s how Art had it set for his machine running in MM. After a few scans I started playing with feed rate and it doesn’t seem to change things that much- either how fast the machine scans- nor the quality of the scans. It does effect how fast the machine Re-Zeros itself after the scan is finished though. Not really sure about the feed rate will help/hurt. Does a slower feed rate yield better results (i.e. smoother scans) or just take more time? Yet another Hmmmmm.
I stepped the Y at .039 (Inches). Default I think = 1 (again probably 1mm-but that’s on that ‘crazy’ other measurement system so I use 'our' systems convenient
# .04”. Starting out small I’ve been scanning a 4” to 10” area. The scans usually take about 15-30 seconds to complete. At first I scanned only in Y then I tried scanning in both Y AND X but when I open the clouds in MachCloud, I get a message that says, “Use left/right arrows to register the striped cloud, press enter when done”. I press the arrow keys but nothing happens, the mouse doesn’t seem to do anything- so, what’s a guy to do? I press ‘Enter’ (sometimes multiple times and more points keep appearing. The cloud is there but I’m left wondering if I missed something or is that feature just not enabled yet? I have tried scanning a bunch of different things and had varied results. Some things that I thought looked great during the scan, don’t generate a good point cloud at all. Others that I thought wouldn’t scan well, actually produce some good results. It’s kinda weird and I wish I could figure it all out
.I played around with the “Ignore” setting a little but I don’t really understand what it is that I am ignoring. Is this telling the computer if something is lower than this value then it won’t record it? For example, if I had a 2” cube on my table and said Ignore 1.0 then would I get a scan of just the top 1” of my cube? I’m not clear on this one- anyone have the answer on how this works?
Here are 3 scans that I did only in the Y axis. Sorry it's nothing too exciting, I'll try to find some more interesting subject matter. I would rate the scans “OK” but I think that they are no where near the resolution that Art was able to get on the scans of his hands.
1. The trpzd woodblock was 1st. Not too shabby but the points are all really close to each other almost forming a line. When I try to mesh/surface the surface is wavy and smooth and flat like the original block. Is this the scan or something you tweak in Rhino?
2. Since the Vacuum nozzle was black, I thought might not scan well. I was happily surprised to bring up the point cloud. It seems to lack Z depth, as if something got cutoff/pruned down there. Maybe this is another setting/camera angle/height thing? Any advice on this anyone?
3. Finally the wedge of foam. After a few adjustments of the “Ignore Z” settings I was able to get it. Again, this one seems like I have too many points lined up in rows and it gives a distorted wavy look to the cloud even though the subject is flat and smooth.
I suppose spending a little time using the touch probe method of digitizing would be enlightening and also provide some basis of speed/quality comparison. The MACH3/laser webcam digitizing concept is so promising! I hope that its development matures rapidly as I think MANY would benefit from integrating this process.
I feel I am close but it seems my lack of experience is keeping me from crossing that frontier into the land of clear scans. Arrrg-I love this plugin! I hate this plugin! Maybe some of the dudes who have some more experience, knowledge or even luck would chime it would help me to lose the “hate” part. I have more questions and comments but I think this is a good place to stop for now.
Thanks and Regards,
Sid