Should the sight glass of a steam boiler always be within the recommended range? Or only when firing?
I talked to the guy who originally installed the boiler and he suggested that the pressure was probably a bit high (was set to 1.5 PSI) for our house; if the pressure is too high, then more steam than the radiators can handle is sent out at a time, and therefor the steam doesn't condense back to water at the radiators at first, so the water level gets low and the auto feeder turns on.

I turned down the pressure to just below 1 PSI and it seems to have done the trick, the water level on the site glass doesn't go down as far while the boiler is operating.  Also, according to this article, steam heat pressure really does't need to be high at all, so there is no worry on my end about turning it down.

In order to turn down the pressure I adjusted the screw at the top of the box next to the pressure gauge: