First All Grain help

[covered95]

I did my first all grain yesterday. It was fun and went OK. I boiled about 6 gallons of wort for an hour and lost almost 2 gallons. Might have to do with the fact that it was around 55 degrees outside and raining. The SG on my 4 gallons of wort that went in the fermenter was 1.070. My target was 1.053 for five gallons. i have already pitched the yeast and it is fermenting fine. My question is should I add some water to the carboy to get my gallons up and my gravity down? Is it too late? i had to go to a show after i was done and didn't have time to ask before I pitched. Here is what I was brewing, a Drop Top Clone. Thanks for comments and ideas.

8 lbs American 2 row
.5 lbs crystal 10L
.5 lbs honey malt (canadian eh)
.5 lbs special B
.5 lbs milk sugar

 

[malkore]

at this point I wouldn't mess with it.

you typically want 6.5gallons (or more) to account for your evaporation in 1 hour. but you have to figure out your evaporation rate to know for sure.

 

[Sea]

I would have added water at the time, and I'm not sure why you couldn't do so now?...

 

[covered95]

If I add my water when I transfer to secondary will it mess up the flavor? In hindsight I should have added it preyeast, but is this a good plan B? Also, is the best way to figure out evaporation rate to simply keep track and adjust as neccesary over time? Thanks for the help and I can't wait to taste my first all grain brew.