There’s a point where you have to say, “good enough.” I would’ve like to see the nipples too (I personally think they would add a lot to the realism), but I’m not the one who is putting in the time building that thing. I wouldn’t even know where to start, so good job!
I know that bryce can do some pretty cool optical stuff. But I dont know about textures. My dad used Bryce more than I did and he did all reflective, refractive stuff.
Yes, Bryce is VERY good with optics. Just check out this img I made with it 
But about the nipples, they probably wouldn’t be that hard to add to the model, its just that exporting it from truespace into bryce is rather hard as I have to re-texture everything, then put it back in the same position the previous version was in 
So as paco said, “Good enough” 
Edit: Actually, how about I make a deal with you guys that when I get a better program sometime in oct I’ll redo this unicycle and add the nipples. Fair enough? 
I think your CG is great, don’t worry about the nipples alone, it is a great CG as it is…
On the other hand, if you wanted to make a very realistic unicycle (which you may not) then all the comments here about frame tube thicknes, nipples, valve stem etc would help to do that. plus plenty more like Seat detail, spoke lacing patern, mud, & others that will mean the project takes every day til Christmas .and even then you won’t be able to ride it.
What you have done so far is admired & apreciated, thanks.
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