Panther Cave

[mwillis]

Hi everyone, please check out my 3D model and animation here:  http://youtu.be/vbmgpKKLMyY

Best viewed in High Definition. Panther Cave, named after the giant panther at the far end of the site, contains Pecos River and Red Linear style pictographic imagery dating back approximately 4,000 years. Figures range in size from less than 6 inches (~10 cm) to over 10 feet (~3 m) in height. The larger Pecos River style figures are the most prominent, and include colorful human- and animal-like figures. The portion of the shelter shown in this model is approximately 130 feet (~40 m) long, 35 feet (~12 m) deep, and 32 (~11 m) in height.

-Mark

[Wishgranter]

Woooooowwww.... Fantastic work and presentation of results....

[MCSQRD]

We have been using Photoscan for UAV work, but now I have an underground mining application. The $100 question what did you use for lighting?
MCSRQD

[andy_s]

Mark,

that is beautiful.

[mwillis]

Mcsqrd, LED lamp arrays work well.  You can get a nice one for under $200 (US).

Thanks for the compliments on the animation, everyone.

-Mark

[JRM]

Hi, a how-to would be great ! I would like to try Photoscan on some archeological sites with similar conditions (church crypt, medieval cellar, etc.).

[Oli63]

Veeery beautiful, great work!
Could you please explain how you did it? What software used for the animation etc.?

[tincansassoc]

Nice work mwillis, could you explain your lighting setup a little more? you mentioned you used LED lamp arrays, were these attached to the camera or setup on tripods? and how many did you need? Also about how many photos did you use for the scene construction? this would be very helpful, thanks.

[mwillis]

I'll see if I can write a little tutorial on the work flow soon.

On this project I had enough ambient light that I did not need any additional lighting.  The mouth of the rockshelter is open to the air and some light makes in that way.

I have worked in deep caves where no ambient light was available.  What I've found that works, is that I have the person that knows the cave best (normally an archaeologist/artist) hold an LED array to best illuminate the subject.  It can be very intense work that takes several days when you're trying to capture ephemeral rock art images.  If you're looking to just map the cave in general, having an LED lamp on a tripod works fine and can be done fairly quickly.

The Panther Cave model was built from approximately 2,200 images.  I broke the floor into a single chunk and the back wall into five chunks.  The main reason I broke the back wall into chunks was to get the best resolution possible for the pictographs textured on each.  If I had done the entire wall as a single chunk the rock art would have looked pixelated.

The chunks were aligned and exported out as OBJs and then rendered in 3D Studio Max.  I also recommend retopologizing in Zbrush but didn't need it for this particular project.

-Mark

[tincansassoc]

Great tips, so you have found that only one LED array works best in a zero ambient light situations? or did you only use one because the paintings were on fairly smooth walls? I would have guessed 2 or 3 light sources would be better.

[mwillis]

Tincansassoc, in very dark situations, I prefer to use at least two LED arrays and a third doesn't hurt.  Caves are really tricky because the shapes can be so complex.  You've also got to keep the light at a fairly constant angle as you move deeper into the cave or Photoscan can get confused.  I compenstate for this by taking a LOT of extra photos and cull out those are not needed in post processing.

I hope to be able to share some work from a deep cave soon.  It will knock your socks off.

[tincansassoc]

Sounds great, I look forward to seeing more of your work.