BTW, Investor RT has great Renko charts.....I use it for some of my trading charts......... http://www.linnsoft.com/renko/
The basic premise of your question is flawed. Renko bars (range bars, volume bars, etc) do not capture the trend, at best they will show you price momentum. So your qustion should be "how do you capture the trend, and then what do you use to show momentum?
They are two completely different things. Trend I define trend as the tendency of price to move in one direction over another one. This automatically gives me a greater than 50% chance of success on all of my trades. Momentum I define momentum as price moving directly in the direction of the dominant trend. *** When you combine momentum with trend you will be able generally trade in a successful fashion. At that point, you will encounter the other things which tend to get in the way of successful trading (like greed, overtrading, being lazy, etc.)
I would define trend as the direction in which price is moving, which *should be* clearly illustrated on a Renko chart. I would definie momentum as the speed at which price is moving (in the direction of the trend. If price is taking forever and going up 1 point per 5 minutes, that's slow momentum. It's it's shooting straight up like what happened this afternoon then that would be high momentum. So I guess by my definition, momentum is "the speed at which renko boxes are appearing" and trend is "whether the boxes are green or red."
I agree. But for your description of momentum, I call that price acceleration/speed. My definition of momentum is the continuous directional movement from the support of market participants.
using shorter time frames like 1 min also subjects Renko to lots of noise, 5-min timeframe is longer but more accurate. I use same time frame 5-minutes but different box sizes .25, 0.50 and 1 box to smooth ... can't speak for the success rate yet as still in the works.