I am wanting to buy a chronograph, at this point it looks like an Ohler, Pact, or CED. I don't need bells and whistles, what I really want is something that is accurate and dependable. I see the Pact and CED have IR screens available, how low does the light have to be before the IR stuff is needed. Also, where is a good place to purchase a chronograph? I can not find a web site for Ohler. Thanks for any info.