Setting up for better scan quality

[Bruce Lee]

Hello all am kind of new to scanning haven't had much experience of producing fine quality scans but now am stuck and in needing of help, basically what hardware do i need to have produce good scans to a fine detail, and the kinds of setup i should use to get these kind of results. So my questions are

1) Camera and projector, what should i be looking for in these two pieces of equipment in terms of specs such as mega pixels.etc.

2) what does having the camera on the left or right hand side of the projector do, and why should i have the camera at a angle same as the projector should i have that facing the object or at the same angle at the projector. Plus what is a good angle to have i was reading up around 10 - 15 degrees is this correct.

3) What does having wider angle lenses do

4) does having a camera with zooming in capabilities help with scanning when you have the camera and projector far away.

5) Finale question for now, Why have a industrial camera or a dslr camera is it due to it's lenses.

Thank you everyone for taking your time to read this question and if you are able to answer them am just trying to build up my basic knowledge of David scanner.

Bruce.

[ShadowTail]

To answer some of your questions:

• 1: That depends on what you can afford. Better resolution = finer details, more accuracy. For a DLSR camera you want live view for fast scans. In general, I recommend 1280x800 as the minimum resolution you should go for in a projector.
• 2: That is required for proper triangulation. An angle of 20-30° gives you more accurate results than an angle of 10-15° at the cost of requiring more scans.
• 3: In general you want to have the projector/camera focus on a narrow area to get more detail out of the scan. Wide angle lenses will ultimately get you less detailed scans.
• 4: Yes. Though you should adjust things before you calibrate. Once calibration is done, you must not change any settings or zoom.
• 5: Industrial cameras and DSLR cameras come with a bigger, faster and higher quality sensor. They produce a lot less noise than, say, a webcam. Plus they give you better results under low light conditions.

Hope that helps .)

[Bruce Lee]

Hello ShadowTail and thank you such a quick and and very clear response this is information has helped me have a better understand of setting up David scanner for better results. I may have a few more question of some other equipment details, but i will give my self a chance to read upon them into a bit more detail before i start asking. But thank you again.

Bruce

[Bruce Lee]

Sorry everyone i have another question should i have the camera pointing directly at the object am want to scan or should i have it higher or at an angle. This also goes for the projector should i have it pointing straight forward or should i have it tilted down or at an angle thanks.


Bruce

[micr0]

To answer some of your questions:

• 1: That depends on what you can afford. Better resolution = finer details, more accuracy. For a DLSR camera you want live view for fast scans. In general, I recommend 1280x800 as the minimum resolution you should go for in a projector.
• 2: That is required for proper triangulation. An angle of 20-30° gives you more accurate results than an angle of 10-15° at the cost of requiring more scans.
• 3: In general you want to have the projector/camera focus on a narrow area to get more detail out of the scan. Wide angle lenses will ultimately get you less detailed scans.
• 4: Yes. Though you should adjust things before you calibrate. Once calibration is done, you must not change any settings or zoom.
• 5: Industrial cameras and DSLR cameras come with a bigger, faster and higher quality sensor. They produce a lot less noise than, say, a webcam. Plus they give you better results under low light conditions.

Hope that helps .)

The sensors in industrial cams are necessarily bigger. In fact a 1/3" chip[ is pretty common and is what most of the imagingsource and Davad 3M cam use. What they do have (which is useful for SL Scanning) is a global shutter, where as a web cam usually has a rolling shutter.

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[Bruce Lee]

Thanks for all the reply i have another question now.

What should i look for when buying a camera to get the best and most accurate scans plus what type is the best option to buy industrial camera or dslr thanks.

Bruce

[NARMELLA]

Hi Bruce,

It is so difficult to answer these questions.

But in my opinion,
Data projector :
The resolution " 800 x 600 " - Has enough ability to use it in scanning tiny or large objects .
Brightness :500 - 2500 lumens

Camera :
David is using a variety of methods to recognize any connected camera and it is not limited to use a special camera .
However they introduced david cam 3 in sls packs
But some of cameras do not recognize by the software . You have to search the forum to find extra information.

To have a nice scanning results ; You have to use a variety of resolutions in camera to select a good one.
I use 1 megapixel up to 8 megapixel .
I have 3 canon eos 600d cameras ; I found that david has not enough control on these kind of cameras then i decided to write the software " Lets Scan ",
To control them.

About Global shutter and rolling Shutter :
In live view scanning ;Best option is global shutter and rolling shutter is good but not the best one.

Good luck
NARMELLA