I think, if we are smart trader, we will use all time frame, because we are need good view from many side of time chart to make better analyze. we are know if forex is really hard to predict. So, we must make good analyze from many time frame to see the minor and major trend. It was really necessary to make good trade. forex best time frame is as you take as best for you. in history body would work however the best option the first is rely on the kind of your own buying and selling because scalping or even temporary or even long-term buying and selling we industry every day and so i make use of the time period 1 they would as well as four hs. so i do that.