I model in HO and have been using medium size ballast but in some of the past posts Ive read some prefer to use fine ballast. Does it make a difference what size it is or is it just a personal preference?
In many cases it’s a personal preference. To me the fine ballast is much closer to scale but to see just all fine ballast gets boring. So I mix in some medium ballast for variety and sometimes I use fine talus.
I too mix fine with medium. I also use two similar but different colors in the mix. Sometimes a few cinders as well. It makes it look more realistic. The Hudson River East Shore in Hyde Park has at least five distinct colors in its ballast. That surprised me the first time I saw it.
Here’s another vote for a mixture of fine and medium ballast. Although I think next time I may use all fine ballast and mix a couple of different yet similar colors as suggested by larak.
Tom