Jump to content

LP calculation: single vs multiple sphere(s)

Recommended Posts

Quick math question:


How does using multiple reflective spheres impact light position calculation accuracy?

Is the use of two spheres advised only as a redundancy?

Or does the HSH-Algorithm calculate a mean value of the respective light-positions?

If so, wouldn't it be better to use 4 spheres (one in each corner of the image) to improve accuracy?


All the best,


Share this post

Link to post
Share on other sites

Hi Tom,


Right now the RTIBuilder only uses one sphere to calculate the light position.  Please note that neither the HSHfitter nor the PTMfitter calculate the light positions, they need a light position (.lp) file in order to run.  So, RTIBuilder calculates that for you based on the sphere.  RTIBuilder can generate a highlight file for each sphere, but we haven't had a chance to implement calculating the light position from 2 spheres into the software.  There is some research software that calculates the light position from multiple spheres, and it is more accurate than using a single sphere.  So, we recommend using 2 spheres when possible, so that your data has the ability to take advantage of this in the future.



Share this post

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...