First, thank you! It felt good to make some progress on something again.
As far as resources for rendering / painting form / etc, I spent all weekend thinking about this. I've had a lot of practice. A lot. Thats probably where I picked most of it up through the years. Lots of studio art classes. Lots of sketching / drawing / etc.
As far as actionable advice, I don't know much about your process but I will try to suggest some things that I actively do.
I'm going to link you to a chalk sponge brush that I LOVE. Not great for getting sharp edges, but is very helpful for blending values. I do also use soft round and some of marc's brushes depending on what I'm doing but this is a specific tool I'm using.
Get that brush here - it's free.
Any time I'm rendering I have opacity Jitter on, but I also adjust the master opacity of my brush to get more subtle blending if I need to. I usually keep it between 60-80 when doing this, but have taken it as low as 30 if I really just want to barely adjust things.
As far as form goes, I think that really was just logging hours. Observation. I was fortunate enough to have a lot of studio art classes where we used live models. Copying photos is fine, but I made more progress when I was observing in person. Still life paintings aren't really covered in the beginning like they were for me in college, but before we painted the human figure I had a whole semester of still lifes we did that forced us to observe the relationships between objects, the light, the shadows, etc. Using a variety of textures surfaces.
I'm toying with the idea of recording myself tonight to maybe re-examine my process to see if there's anything else I'm doing that might help others. In the mean time if I find something useful I'll make sure to share it.
