If you CAN, my opinion is you should. Meshes benefit from normal maps in ways other than edges and details. Especially if anything on the mesh isn't flat. That high poly smoothing always looks better than vertex smoothing...
Baking in xNormal, importing to UDK. Strangely enough, I got it looking correct by going back to the low-poly mesh, unsmoothing everything that was smoothed... and smoothing everything that was unsmoothed. Looks pretty much just the way I wanted it to originally. :poly105:
Deformation Cleaner is a modifier for 3ds Max that smooths arbitrary deformations of a model without smoothing the original detail. It can be used as a fast post correction step on top of any deformation. More here http://www.mariussilaghi.com/products/deformation-cleaner…
Gradients on normal maps are perfectly normal behavior like gnoop said. It's from the normal map having to compensate for the shading/normals/smoothing on the low poly model. Are you sure Substance Painter is importing the smoothing on the low poly model?
I believe those huge hollow circles are already a single smoothing group. I made the smoothing groups before i UVed. This model has an inside so i can make the textures for the inside have less detail.
If there's weird mesh pinching you want to smooth out, try using the smooth brush with the Shift modifier, but then RELEASE the Shift button when you're drawing on screen to use a different algorithim that may get your the results you want.
Hmm have you checked your smoothing groups? Each smoothing group should have its own UV shell before you bake your normals. Also I'd get more padding in there, just to be on the safe side.
Would've been nice to mess around with more detail but I just ran out of time in the end. Plus looking at shark references they seemed to have quite smooth skin so decided to keep it smooth and slimy :P Thanks.
Also don't forget to put everything in one smoothing group before you export your lowpoly. Select all the polys of your model, go to smoothing groups and hit clear then hit one of the little numbers under clear.
Concerning the stock, the back of the grip and interior edges are too sharp and the overall shape is not as smooth as it should be. Noticeable smoothing errors where the bottom and top curvatures meet the flat. Here are some refs: http://foto.mail.ru/mail/photoshooter/839