Another OG question.

So on my brew day today, my target post-boil SG was 1.061. My measured was 1.065. I hit my pre-boil and my volumes were on. (At least to the accuracy that I'm able measure with my equipment.) Will this slight difference make that big of a difference in the finished product?

Is there a way that Beersmith can calculate how my starter will affect OG? Or do I just need to add it and take another reading? (1 liter starter @ 1.040 using Wyeast French saison)

Brewing for a competition and I want to be as accurate as possible.

Your OG is always taken before you pitch your yeast so you shouldn't be taking it after you pitch a starter.

Your OG should be fine. 0.004 points is only going to equate to maybe 0.2 or 0.3 % change in ABV. Pretty negligible.

I think in BeerSmith there is a way to tell it if you pitch a full starter or decant first. I am not sure where that option exists though and what effects, if any, it has. I think it would only really effect your volumes.

I wouldn't worry too much.

You can use the "Dilution Tool" in Beersmith for this (under the Tools menu at the top). Enter your starting volume and your OG. Change the "Dilute with" drop box to "wort or beer". Most starters, if made with the standard 100 gms/1000 ml will be approximately 1.040 SG which is the default, but you can change this if needed. Enter the volume of your starter and the tool will adjust your specific gravity. Try this a few times and you will see that a small starter has little or no effect on the OG.