Question: I've heard that (insert favorite program) runs much faster than EMAN. Is this true ?
Answer: The quick answer is: EMAN strives for the best, most accurate solution, not the fastest solution. That may sound like a 'yes', but it definitely is NOT. It is quite possible to make EMAN run very fast, indeed. It all depends on the options you use. In the early rounds of refinement, or when you are still trying to determine the quaternary structure of your object, you are strongly encouraged to do things that will provide many different results to compare quickly. This includes downsampling the data, using a coarse ang=, and not using the 'high quality' options to the refine command, like dfilt and refine. When you are trying to get your final reconstruction for publication, you generally are after accuracy, not speed. If use all of the highest quality options, EMAN can be quite computationally intensive.