Sketchfab Forum

3D Scan of Organ


(Calvin Nz) #1

Hi There. I’ve been contacted about a possible job in scanning a Church organ.

Here is an extract from his email

“I work for a pipe organ builder. We have an organ that needs to be documented before removal from the building. The multiple spaces in which it is installed is very cramped. A 3D map or set of drawings with dimensional information would be very helpful in a project to rebuild the organ in the same location.”

I have not had a chance to talk with him as yet and am wondering what the community’s thoughts on how best to scan this. I’m skilled in photogrammetry and wondering if this would be possible at all (maybe in chunks?) Secondly should i just hire a laser scanner and do it that way.

Would appreciate your discussion and suggestions on how best to tackle this.

Kind Regards

Calvin


(Nomadking) #2

I would say with the cramped spaces, and the uneven lighting that will bring, this would be a challenging piece to capture with photogrammetry - even in chunks. Although I’m far from an expert in this, so perhaps some more experienced users can offer a better opinion :slight_smile:

Also, from the excerpt you posted, it appears they intend to rebuild the organ from the results of the scan, so accuracy is going to be hugely important to them. That alone makes me think this would be better laser scanned.


(Mesheritage) #3

It looks like a very crowded room with not much light, might be fun only for the “logistic part”!

I never scanned “metal tubes”, the close to that was golden object and furniture (still bit far).

Just few advice:
Forgot about the laser scan if you don’t have one or trained with it. It is not as straighforward as it appears and does not handle well reflective surface. You might acquire a scan with confidence of accurcy but without thourough check, it might not be the case. Also you would have to use a lot of different station points for such object.

Also, sometime it works nicely to recreate manually some part, like the tube. You can measure all the dimension by imaging and input that into “3D tube” as they are looking for “dimensional drawing”. The fact to scan it does not make it more realistic, the way to scan and the different software bring different error and accuracy. So if they are looking at a dimensional drawing, sometime better to focus on the imaging and extract the correct value using SFM on more complex part like the bottom one (and bottom of tube). Like this you avoid the big processing on the tube and you can get an higher confidence in the accurcy.

Look like a very long project!


(Alex Nan) #4

Brake it down to chunks, my bet :space_invader:
Make a map of the organ and try to see the best way to brake it down in parts and scan it.
The laser scanning/ blue light scanning would be the same in chunks because of the space available there


(Gerpho) #5

Photogrammetry could do the job : these tubes don’t seem that much reflective, there are lots of tiny features on the tubes that are fine for reconstruction. The main difficulties IMO are 1) to set up a diffuse overal lighting (avoid direct flashlight) and 2) how to move around the organ to shoot it from all directions (ideally a small crane or elevating platform, but removing the organ will probably require such a device, so that it shouldn’t be a problem).
If this can be solved, then shoot with maximum sharpness and details to catch the texture of the tubes. Carefully plan shooting sequence, and make sure you have a lot of photos for redudancy. Accuracy will come with photogrammetry ; I usually consider accuracy to be 3 times pixel resolution. Of course this requires making a few manual dimensional measurements which will be fed to the software before reconstruction.