Messages

181

General / Re: 3D Print: Non Manifold faces. Best practice?

« on: September 02, 2013, 09:50:23 AM »

Albert,

Typically you would lose the color info, unless your repair application can preserve vertex color.

There is a process in Meshlab to reproject the vertex color from one mesh onto another, so in theory, you could repair the mesh in another app (I have found Meshlab not very useful for repair), bring it back into Meshlab and transfer the color from the bad mesh to the repaired mesh.

I have yet to try this myself.

182

General / Re: 3D Print: Non Manifold faces. Best practice?

« on: September 01, 2013, 08:34:09 PM »

netfabb Basic is free, and can repair a lot of these issues, but its 32 bit only.

netfabb also has a cloud service which is free (or was free) that can handle more repairs, but you have to upload/download your model which can be a hassle.

I purchase netfabb Pro which is 64 bit, and has thickening and boolean functions.

183

General / Re: exporting model to CAD

« on: July 18, 2013, 04:54:12 AM »

3ds format is limited to about 65,000 triangles per object. Some 3ds exporters in other apps are able to split an object larger object than 65,000 tris into multiple objects. I don't know how Photoscan handles this.

If you are using vertex color in the PLY file, your "texture" is dependent on the point density. In other words, you would not have have a separate texture map, and your "texture" is actually created by the color of the vertices in your model.

I am new to Photoscan, but I think there must be a way to save the model with a separate texture map. 

184

General / Re: Compact Canon CDHK RAW & Lens Distortion

« on: July 17, 2013, 08:18:51 PM »

That is excellent!

I've been wanting to do something like this myself ...

What did you use for a rig to hold the cameras?


Chris

185

General / Re: Accuracy measurement?

« on: June 29, 2013, 04:23:28 AM »

With more experience with Photoscan, I will probably be able to make some "educated guesses" about the accuracy of the results based on the subject characteristics and the shooting conditions.

What I was considering was shooting a bunch of objects in perhaps 3 size ranges, similar to a baseball, a car, and a building. However, based on the feedback so far, this does not sound as useful as I had anticipated to make some generalizations about accuracy.

186

General / Re: Accuracy measurement?

« on: June 26, 2013, 07:00:57 PM »

Hi Ralf,

I understand there are MANY variables.

The fewer variables that change, the more predictable the results will be. So assume I use the same camera, lens, distance to subject, take the pictures from the same locations, etc. So essentially the only thing that changes is the subject, but the subject is the same size. Lets also say the subject is static.

Surely the accuracy could be reasonably predicted if the only thing that changes is the subject?

What I would like to find out is if I have a human (or house, or baseball etc.) sized object, all other things being equal, what I could expect for accuracy compared to other similar sized objects.

I am NOT asking for the specific amount of error. I would like to know what a reasonable approach to repeatable accuracy would be. Obviously, you can't put everything in a studio under completely controlled conditions. If I am taking photos of houses, I am not going to take the pictures from the same relative positions every time.

So, if you can't take the pictures from the same relative locations, what would be the next best thing to do, ie same distance?

187

General / Accuracy measurement?

« on: June 26, 2013, 04:04:16 PM »

Hello,

I searched the manual, forum and the wiki and have some good information about best practices for using the software and camera but did not see anything that answers my question below.

Is there a method that can predict the accuracy for an object (an "approximate" range of values is OK) that could apply to future situations without loading the images into Photoscan to get the values?