Hello 3dscanforum,
i hope that you can help me with some trouble that i have with my sls setup.
My setup:
David K135+ projector
IS 23ux174 HD camera 1" sensor
fujinon 16mm megapixel lens
David5
David glass calibration panel
manfrotto tripod and fixtures
turntable
board game figures as sphere targets // target stickers
developers spray (crack detection equippment) in some cases
I tried most of my scans on 120 and 240mm calibration panel.
The scans are okay, could be a bit more detailed, but i need the shape for reverse engineering.
The problem i have are the problems during alignment. Auto alignment doesnt work good, manual alignment is better but still with deviation.
Using geomagic design x the sphere registration is not stable, auto align also fails, manual alignment has the same deviation.
Alignment is not a issue of the software used, its a issue of the scan quality.
For calibration i exactely orientated the panels to 90deg.
Distances are acc. the table stated in sls1 manual, which is easy trigonometry.
Angle is around 20deg.
What i realized is the issue, that my cameralens is too wide and i capture more than the pattern.
I could reach more details with another lens, but is this the problem for alignment?
The components should be capable for good scans, would be nice if you help me with the correct use of them.
Some pictures will follow.
regards, Spark
alignment problem
Re: alignment problem
//i can also provide a sample file, if this helps to identify a problem?
regards, spark
Re: alignment problem
The focal length of the camera length shouldn't matter to the calibration. A couple of observations about the pictures you posted.spark wrote: ↑11 Mar 2017, 21:11 Hello 3dscanforum,
i hope that you can help me with some trouble that i have with my sls setup.
My setup:
David K135+ projector
IS 23ux174 HD camera 1" sensor
fujinon 16mm megapixel lens
David5
David glass calibration panel
manfrotto tripod and fixtures
turntable
board game figures as sphere targets // target stickers
developers spray (crack detection equippment) in some cases
I tried most of my scans on 120 and 240mm calibration panel.
The scans are okay, could be a bit more detailed, but i need the shape for reverse engineering.
The problem i have are the problems during alignment. Auto alignment doesnt work good, manual alignment is better but still with deviation.
Using geomagic design x the sphere registration is not stable, auto align also fails, manual alignment has the same deviation.
Alignment is not a issue of the software used, its a issue of the scan quality.
For calibration i exactely orientated the panels to 90deg.
Distances are acc. the table stated in sls1 manual, which is easy trigonometry.
Angle is around 20deg.
What i realized is the issue, that my cameralens is too wide and i capture more than the pattern.
I could reach more details with another lens, but is this the problem for alignment?
The components should be capable for good scans, would be nice if you help me with the correct use of them.
Some pictures will follow.
regards, Spark
first is that it seems the exposure level on the scan subject is a bit low. When setting up, before calibration I set my exposure to the part then adjust up or down the brightness of the projector to not overexpose the calibration panels.
It also looks like you are trying to scan a reflective or slightly shiny surface. is this correct? have you tried coating it? I find that even with David 5 reflective surfaces cause problems. Though not really the ones you seem to be having.
Just to double check, Optimize dual camera calibration is off, yes?
Try calibrating with a less acute vertical angle relative to the calibration panels. That is, try placing the projector and cameras more straight on to the panels.
The surface alignment in the center of your scan field looks fairly good. It looks like the surface curvature is very close to matching but dimensionaly it's off.
Are those panels and panel holder the ones sold by David (OEM)?
µ
Re: alignment problem
BTW: How big is the part and what size/scale calibration panels are you using?
µ
Re: alignment problem
I think the topic fits better in "Troubleshooting" and moved it there.
Re: alignment problem
Hi µ,
your questions:
Amplification is:-4
what do you mean with
I will use coating spray on all future tryouts...
//by the way: what is the reason for tilting the projector relative to camera? i implemented it like in the sls2/3. angle by instinct.
regards, spark
your questions:
yes, i am running on max projector brightness. and aperture of 16. the exposure is 1/60s in order to avoid waves.first is that it seems the exposure level on the scan subject is a bit low.
Amplification is:-4
what do you mean with
are you changing the exposure time? /as the multiple from 1/60s? / or are you using the gain setting?When setting up, before calibration I set my exposure to the part then adjust up or down the brightness of the projector to not overexpose the calibration panels.
yes, it is uncaoated aluminium but low reflective. i tried coating spray on other parts, the acquisition is better but the alignment was similar bad.It also looks like you are trying to scan a reflective or slightly shiny surface. is this correct?
I will use coating spray on all future tryouts...
japp!ust to double check, Optimize dual camera calibration is off, yes?
next time i will take care about this!Try calibrating with a less acute vertical angle relative to the calibration panels. That is, try placing the projector and cameras more straight on to the panels.
yes original ones.Are those panels and panel holder the ones sold by David (OEM)?
approx 400mm long and 240 patternHow big is the part and what size/scale calibration panels are you using?
//by the way: what is the reason for tilting the projector relative to camera? i implemented it like in the sls2/3. angle by instinct.
regards, spark
Re: alignment problem
what is the reason for inaccurate acqusition of target stickers?
partly good partly bad...
outliner removal is set to 0.
regards, spark
partly good partly bad...
outliner removal is set to 0.
regards, spark
Re: alignment problem
... it's mostly the colour/absorption or reflectivity -- pure black and shiny/mirroring surfaces are hard to scan correct,
Viktor
Viktor
Viktor
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- Posts: 11
- Joined: 07 Mar 2017, 07:47
Re: alignment problem
pictures of david program shows the resolution of your acer k135+ as 1280x1024 while the native is 1280x800...
Re: alignment problem
The targets are special 3d scanning targets and should be recognized fairly good?!
sorry, my projector is the 132+ but the point with the resolution is the same!
it was choosed by the system as default and i havent questioned about it!
Thank you! i will shortly reset this!
regards, spark
sorry, my projector is the 132+ but the point with the resolution is the same!
it was choosed by the system as default and i havent questioned about it!
Thank you! i will shortly reset this!
regards, spark