What is the correct wort collection technique?

[booldawg]

After 15 AG brews I'm now questioning whether or not I use the right technique for collecting wort pre-boil.

I batch sparge and collect enough wort to allow for the losses due to steam and hop retention. For example if I want 23L in the FV I'll batch sparge to collect 30L of wort,

This means that I never top up the boil with brewing liqour as I start of with (roughly) the correct amount of wort.

I'm not sure if this plays havoc with my efficiency readings as I always tend to over-hit gravities (according to Beersmith) Without accurately measuring out the wort in the FV I'm pretty sure I'm not under or over collecting by much so I guess I'm starting out with enough in the FV.

Would collecting 30L of wort and boiling down to 23L make it concentrated and give me the higher gravity? Should I start off with 23L of wort pre-boil and top up with brewing liqour from the HLT during the boil to ensure I get 23L post-boil?

[booldawg]

Thanks Chris. Seems like I am doing it right then