Yeah. I'm 42. . . and my vision is definitely not what it used to be. So I know exactly what you mean. But, 1,500ft that's a good guide.
Second question: 1,500ft altitude on a Big Bertha with reduced 12" parachute or huge streamer for recovery. . . any idea how big a field that would require?
As a kid I would launch on whatever field was available. Most fields were tiny, so I would have to stick to A and B engines. Still, I had so many small parachute rocket models fly away that I became paranoid of parachutes, and either converted to streamer or cut out the center circle of my chutes.
Now I have access to a larger field, but I still wonder.
Thanks.