Study of a Photogrammetry's object size limits with two inch figurine.
High poly - photogrammetry, 931 849 triangles, 64 photos (Nikon D5300).
Low poly - manual retopo, 5 454 triangles, 2 905 vertices.
Software - Agisoft Photoscan, ZBrush, MODO, Substance Painter, Marmoset Toolbag 2.
The point of this work is to study whether small objects are suitable for photogrammetry and how detailed the results for small object can be. To find this out, I decided to take photos of the small two inch Ebisu figurine that I found at home and turn it into game-ready asset. Ebisu (also transliterated Yebisu) is a Japanese god of fishermen and luck. He is one of the Seven Gods of Fortune, and the only one of the seven to originate purely from Japan without any Hindu or Chinese influence.
At first I've had some troubles with the bottom part of the figurine - I just could not get an acceptable level of detail on this part. It was necessary to raise the figurine up a little bit to get better pictures, so I've used a shot glass in the role of the stand. As you can see I've turn the shot glass upside down and it's metallic bottom became the part of the final result. I think in the end this metallic part fits final model quite well and gives it an unique look.
Base albedo and relief information were obtained during photogrammetry. High poly mesh was quite good to begin with, but I've cleaned it in Zbrush a little bit before baking anyway. Base albedo was also quite desent, due to using polarizing filter and good lighting during the photoshoot. But I've also cleaned the albedo map later using an object space normal map to remove remains of ambient lighting.
My plan was to get the model detailed enough to be used as 6-10 inch statuette, that could be a part of the apartment's interior on any modern real time engine. At the same time I wanted to end up with least amount of polygons possible. For these reasons, I did retopology manually instead of using fully automatic retopology tools.
There are only two distinct types of materials in this figurine (stone and metal), so I went with metalness PBR workflow (instead of specular one) to use less texture memory. Rougness map, metalness map and extra details for albedo, AO and normal maps were created in Substance Painter.