Agisoft Metashape

Agisoft Metashape => General => Topic started by: endy on July 22, 2020, 07:27:18 PM

Title: Scanning tiny objects
Post by: endy on July 22, 2020, 07:27:18 PM

Hi,
I'm looking for some tutorials/guidlines for scanning tiny objects, namely plants.

I've done a test with a wheat spike and it looks half decent, for a couple of picture taken with a phone. The problem is that when I took a bunch of photos with a DSLR and mounted the same object on a turntable the software didn't even localized cameras properly (I'm guessing not enough distinctive details to cross-reference cameras)

So my question is if there are some tricks of the trade for doing small objects like this? Put it on a printed pattern that will help localize it in space and then combine the two parts? Keep it on a turntable, but add other distinctive objects in the frame?

Title: Re: Scanning tiny objects
Post by: Cyberworld on July 29, 2020, 01:51:27 AM

I wouldn't expect that you need to do anything different than photogrammetry for non-tiny objects. You'd need a decent DSLR (preferably over 25MP shooting RAW), a macro lens (60-90mm would do), good lighting for macro, and a turntable for really small objects. I've tried pottery sherds and jewellery and had excellent results, albeit it needs patience (lots of masking) and in many cases re-running alignment with different settings.

Title: Re: Scanning tiny objects
Post by: endy on July 30, 2020, 04:33:06 PM

Thanks ... I did some experiments and it kinda works (better than expected), but I still have difficulties merging chunks.
Still a lot of things to figure out.

Title: Re: Scanning tiny objects
Post by: Kiesel on July 30, 2020, 04:56:55 PM

Hello Endy,

The shallow depth of field makes a difference to normal shooting, but I have seen very good results even of insects here.

Are you aware of these to blogs?:

https://www.agisoft.com/index.php?id=48

https://www.agisoft.com/index.php?id=49

Kiesel