Coffee Appreciation

Have you been awake since you started this, how many shots have you drank?

This flow looks fine to me. I think from here it's just a matter of dialling in and finding a coffee you like.

Just got to remember that not all coffees pull good espresso and not all coffees pull good looking espresso. And to throw a spanner in the works sometimes you just get a batch of coffee that doesn't perform like the previous one did. Your local water will also affect all of this.

I think get some cheap or reliable beans to play with. Sounds like you don't like darker roasts, so for cheap get a load of Lavazza gold if it's on offer, or for reliable get a kilo of Yellow Bourbon espresso blend.

Personally, I don't go by weight, I still do it the old way on volume. So the compacted dry puck is the same height each time and I prefer it to touch the shower screen. Why? One of my sidelines at work is permeability in composites (flow of resin through carbon fibre) and one of the key things is having the cavity full and compressed, otherwise the fibres are displaced by the flow and you get channelling and race-tracking. Coffee does exactly the same thing in the portafilter. As soon as you wet the grounds they try to move around. If you give them somewhere to go, they will move. So I don't like it when there's a head of water above the puck because you end up with a puck where the ratio of grounds and water is wildly different at the top and bottom of the puck. Completely displaced at the top down to still compacted at the bottom?