Really sorry Zelig that I missed your first and subsequent posts here until now.
You did really well on your figures for a mini-BIAB

. 1.052 versus 1.048 is an excellent margin of error and there are many things that could explain this.
I am really pleased to see you took so many measurements

. It makes things much faster to fine-tune.
I can't comment on the figures from a single brew as there are so many variables. What I will say, is that evaporation rate is the first thing to concentrate on. It is the only figure that a new all-grainer can fine-tune fairly quickly.
The second area (even more important that evaporation) is efficiency into kettle (EIK) and all software, including the Calculator, gives no help in this area

. (There is good news though - see below!)
Efficiency into Kettle (EIK) and therefore all other 'efficiency' figures vary with the original gravity you require. If we exaggerate a little bit, you obviously won't get the same 'efficiency' for a very high OG beer as compared to a 'low alcohol' beer because the former is getting just a 'spray' of water compared to the latter's 'soaking'.
This is a major, major flaw in all software including The Calculator. This flaw in all the software 'teaches' the user (and everyone who posts) that efficiency is a constant.
Efficiency of any kind is not a constant. It is a actually a complex variable.
The good news is that the 'BIABacus' (the new calculator for this site) will address this basic flaw.*
I really enjoy reading threads like yours. I don't think I have ever seen a new brewer take so many measurements. Taking as many measurements as is practical avoids or quickly rectifies the problems listed
here.
And, it also means that you are paying
attention to your brew. Paying attention, I think, is the fastest way to learn. Taking measurements is a good indication that you are doing the 'paying'.
My apologies that I didn't see your original post until now Zelig.
Great job

,
PP
* Stux has done hours of study and research on this. Sigurdur is now trying to write it into the new BIABacus.
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