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tomorrow i am going to buy

Problems, solutions and discussion about scanning with a video projector and stripe patterns.

Deformations and waves

Postby hal » Sun Nov 29, 2015 2:21 pm

Hello fisa,
here some things I guess are related to the problems (deformations and waves):

- Why do you put a sheet in front of the projector optics? I guess in order to reduce the brightness, right? Unfortunately this solutions isn't the best and it can only create more problems. If you want decrease the light brightness, please use the projector brightness control into David interface, or/and move far the projector from the corner, then increase the frequencies value of patterns;

- the glass corner is a nice solution, because it is flat, but from your screengrabs seems that you have a bloom effect alla oround the printes sheet with the markers. I suggest you to paint the glass with a matte paint in order to avoid the sub surface scattering effect of the paper sheet;ù

- Set the exposure value of the camera, into the David interface, to the same Hz of your projector (that is the second monitor - usually are 60Hz -> 1/60);

- did you set off the "autoKeystone" function of your projector? Be sure your projector don't have any correction of the optics applied value.

Let me know,
Mattia

p.s.: as DerHuette said, if you aim to get pro- results with David,you need totally better hardware. David SLS-1, or -2 or -3 packs are the best solution. If you want assemble yourself hardware, please look at the signature of the David's users and check our posts and results.
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Re: tomorrow i am going to buy

Postby fisa » Mon Nov 30, 2015 6:56 am

DerHuette wrote:And your problem are the stripes on the scanned calibration panel?
If you search the forum you will see that there might be many reasons. I think most likely is missing sync between camera shutter and projector refresh rate. On which refresh rate is your projector working?

I have less stripes if I do a combined setup, camera vertical AND horizontal from the projector. And, very often I see stripes on the calib panel but not on the scanned object.

On the other hand, if you do that as a profession, you should consider upgrading from a simple unmodified webcam. Go and buy the David cam!


Respected Derhuette
Really thanks for ur input.
My projector refresh rate is 60...with default resolution is 800x600.
u mean if I have a right sync between camera and projector.. then I can get strips less and smooth scan data with my current hardware..???if this is a case then how I get sync between camera and projector..

Regards
Fisa
Epson PowerLite S1+ LCD Projector
logitech c920 unmodify
david version 3.4.0
win7 32 bit
512 mb graphic card
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Re: tomorrow i am going to buy

Postby DerHuette » Mon Nov 30, 2015 10:09 am

Just from what I read in the forum, and with my own experiences and thoughts I would say that there is no way to sync camera and projector. If you have luck, they are in good sync. Next day it may be worse. That explains that sometimes you have more, sometimes less stripes. At least do I experience that. But be aware, these are just my thoughts and I am not a developer of David.

I have better results since I changed the projector refresh rate to 75Hz in the graphic card driver. Maybe you experiment a little with refresh rates and shutter speeds. In theory they should be multiples, e.g. shutter 1/30, refresh rate 60Hz.

When I look at your bottle scans, the stripes aren't that bad?! Especially the one with the calibration panel in the background? I would say with your hardware setup the results are ok, aren't they?
Acer K11 with closeup lenses, Canon EOS 550D
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Re: tomorrow i am going to buy

Postby fisa » Sat Dec 05, 2015 3:02 pm

respected hal & DerHuette

really thanks for ur advises i follow both of ur suggestion and know i feel that i achieve some thing very good as compare to my previous result please check and advice me if there is more place for improvement..i attach again my setup images and my results

regards

fisa
Attachments
live view.png
live view-2.png
canmera setting-0.png
Epson PowerLite S1+ LCD Projector
logitech c920 unmodify
david version 3.4.0
win7 32 bit
512 mb graphic card
fisa
 
Posts: 63
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Re: tomorrow i am going to buy

Postby fisa » Sat Dec 05, 2015 3:03 pm

continue thread
Attachments
canmera setting-1.png
canmera setting-2.png
scan-view.png
Epson PowerLite S1+ LCD Projector
logitech c920 unmodify
david version 3.4.0
win7 32 bit
512 mb graphic card
fisa
 
Posts: 63
Joined: Sun Dec 07, 2014 10:26 am

Re: tomorrow i am going to buy

Postby fisa » Sat Dec 05, 2015 3:04 pm

continue thread
Attachments
2015-12-05_18-39-32.png
result with fusion
Epson PowerLite S1+ LCD Projector
logitech c920 unmodify
david version 3.4.0
win7 32 bit
512 mb graphic card
fisa
 
Posts: 63
Joined: Sun Dec 07, 2014 10:26 am

Re: tomorrow i am going to buy

Postby hal » Sat Dec 05, 2015 7:17 pm

Hi fisa,
good to see that the waves disappears.
But from what I see in your shots, the patterns are still too flat: no good white values. Please set a little more the projector and camera values. You should have a nice white color in the camera view. Now it looks flat and grey.
Mattia
PC: DELL Alienware 17, Intel I7-4710MQ, 32 Gb Ram, AMD Radeon R9 M290X 4GB.
SO: Win 8.1 64Bit.
CAMs: USB 3.0 CMOS B/N (1280x960, 60 fps).
LENS: 12 mm.
PROJECTOR: DAVID SLS1 ACER K11.
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Re: tomorrow i am going to buy

Postby fisa » Sat Dec 05, 2015 8:25 pm

hal wrote:Hi fisa,
good to see that the waves disappears.
But from what I see in your shots, the patterns are still too flat: no good white values. Please set a little more the projector and camera values. You should have a nice white color in the camera view. Now it looks flat and grey.
Mattia


Thanks Mattia for your advice... regarding pattern.l have some questions about it.

What is mean that pattern are still too flat? Can u highlight on my uploaded images.
What about my other settings?? Like Camera resolution and frame rate. exposure ???
And about camera and projector values..please point me which setting I have to change ...in camera settings is GAIN or BRIGHTness or sharpness or contrast and in projector which specific value I have to change to achieve nice white color in camera...

Regards

Asif
Epson PowerLite S1+ LCD Projector
logitech c920 unmodify
david version 3.4.0
win7 32 bit
512 mb graphic card
fisa
 
Posts: 63
Joined: Sun Dec 07, 2014 10:26 am

Re: tomorrow i am going to buy

Postby Idea Beans » Sun Dec 06, 2015 10:55 am

hi fisa,

May I ask why you had the calibration panel behind the scanned bottle? Is there a particular reason you scanned with the calibration panel in place?

Of all the scans I've done, I always removed the calibration panel from the desk after I've calibrated the camera and projector angle... I'm just wondering if the white surface from the panel would actually affect your scan results, in terms of getting the colour contrast and exposures right?!

With my setup, I had the desktop surface covered in matt black vinyl, and a black fabric covering the white wall behind the object. That way all the camera can see is the object itself....
Projector - Acer K11 / Acer P1285 SVGA HDMI 3200 Lumens (larger scale scans)
Camera - DAVID Cam 3 (preferred) / Logitech C920 HD Webcam (poor quality, doesn't work with DAVID 4)
Software - DAVID 3 / DAVID 4

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Re: tomorrow i am going to buy

Postby fisa » Sun Dec 06, 2015 12:42 pm

Idea Beans wrote:hi fisa,

May I ask why you had the calibration panel behind the scanned bottle? Is there a particular reason you scanned with the calibration panel in place?

Of all the scans I've done, I always removed the calibration panel from the desk after I've calibrated the camera and projector angle... I'm just wondering if the white surface from the panel would actually affect your scan results, in terms of getting the colour contrast and exposures right?!

With my setup, I had the desktop surface covered in matt black vinyl, and a black fabric covering the white wall behind the object. That way all the camera can see is the object itself....


dear idea bean

there is no reason to place panel behind my object...and actually even i don't know what will be the effect on scan result if place panel or dont place behind my object... i tell you later after i checked it...also right now i have a issue to grab color effect on my result even i checked on grab texture...why i am not getting????

regards

fisa
Epson PowerLite S1+ LCD Projector
logitech c920 unmodify
david version 3.4.0
win7 32 bit
512 mb graphic card
fisa
 
Posts: 63
Joined: Sun Dec 07, 2014 10:26 am

Re: tomorrow i am going to buy

Postby fisa » Tue Dec 15, 2015 12:56 pm

Thanks Mattia for your advice... regarding pattern.l have some questions about it.

What is mean that pattern are still too flat? Can u highlight on my uploaded images.
What about my other settings?? Like Camera resolution and frame rate. exposure ???
And about camera and projector values..please point me which setting I have to change ...in camera settings is GAIN or BRIGHTness or sharpness or contrast and in projector which specific value I have to change to achieve nice white color in camera...

Regards

Asif
Epson PowerLite S1+ LCD Projector
logitech c920 unmodify
david version 3.4.0
win7 32 bit
512 mb graphic card
fisa

Posts: 47
Joined: Sun Dec 07, 2014 10:26 am
Epson PowerLite S1+ LCD Projector
logitech c920 unmodify
david version 3.4.0
win7 32 bit
512 mb graphic card
fisa
 
Posts: 63
Joined: Sun Dec 07, 2014 10:26 am

Re: tomorrow i am going to buy

Postby hal » Tue Dec 15, 2015 2:12 pm

Hi fisa,

I mean that your projected patterns looks a littke dark and I can't see a nice value of white and black with the smooth gradients between them. If you focus on the red sine waves in the viewport, you will see that is under the middle bar and the sine are too large in the pinches. In your old David version the pattern of black and white stripes should looks like a series of gradient between B/W. In your uploaded images (sorry they are low resolution to see correctly) your pattern looks more like a full grey / black checker.

Gradient pattern.jpg
Gradient pattern.jpg (18.64 KiB) Viewed 3569 times

A sine wave from this correct pattern should have small and pinched, pointy extremities (the valleys and depressions of the red sine).
I can't suggest to you the right settings for you camera, because I don't have your device and every cam is different. But will be easy to play with the settings in order to achieve the right gradients of greys between the full black and the full white.

Best regards,
Mattia
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Re: tomorrow i am going to buy

Postby fisa » Tue Dec 22, 2015 9:39 am

Thanks mattia for your valuable advice.. I'll follow ur instructions. And reply back to you..

Regards

Fisa


quote="hal"]Hi fisa,

I mean that your projected patterns looks a littke dark and I can't see a nice value of white and black with the smooth gradients between them. If you focus on the red sine waves in the viewport, you will see that is under the middle bar and the sine are too large in the pinches. In your old David version the pattern of black and white stripes should looks like a series of gradient between B/W. In your uploaded images (sorry they are low resolution to see correctly) your pattern looks more like a full grey / black checker.

Gradient pattern.jpg

A sine wave from this correct pattern should have small and pinched, pointy extremities (the valleys and depressions of the red sine).
I can't suggest to you the right settings for you camera, because I don't have your device and every cam is different. But will be easy to play with the settings in order to achieve the right gradients of greys between the full black and the full white.

Best regards,
Mattia[/quote]
Epson PowerLite S1+ LCD Projector
logitech c920 unmodify
david version 3.4.0
win7 32 bit
512 mb graphic card
fisa
 
Posts: 63
Joined: Sun Dec 07, 2014 10:26 am

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