Hah, you’re asking the wrong member! I saw your question and I’m just as curious as you are about the answer. Learning about proper LED focusing techniques has been on my to-do list for a while now.
It’s probably reasonable that the properly focused beam has a doughnut close up.
I did specifically ask lightme about a focusing technique mentioned in this thread: Convoy S2 Long Range Thrower Mod The response is in post #23 and honestly I’m not sure that I have a handle on it yet. Before asking more questions I thought I’d give it a try and I haven’t had an opportunity to do that yet.