Patchy ceiling

Re-did the ceiling last night with its second coat of Silk emulsion following its initial seal coat (thinned trade mat emulsion) as it’s newly plastered?

But it’s come out as patchy as hell!

Not in the normal sense in as much as you can’t see through it, more with its finish..., some silk and some matt!

TBH you can only see it when I put the up light on and it shines on the shiny bits and highlights the mat bits... The reason for giving it a second coat was I had noticed one small area before on the first coat like this, but now it’s all over!
The ceiling is 5 meters x 3 meters and what I think is happening is it’s drying too quick and then when I’m going over a area as I move down kind of thing, it’s picking up the half dry stuff and making it mat?

The tin should do 15 mtrs square and I used a bit more so I’m putting enough on.... The roller is a bit flat but not that old.. or is it like I say, drying too quick?.. It was hot last night... It says ‘don’t thin’ so I didn’t.. but maybe I need to or get another paint... It’s Leyland BTW.....

Any thoughts?.. I’m guessing speed is key to this sort of painting also and it’s just out of reach so I’m moving a buffet all the time to reach so this slows it down?.....

Thoughts appreciated.... Thanks

Not sure what a buffet is?? but if you're not using a pole you'll struggle to keep a wet edge. Only explanation for the patches of matt is you're missing bits.

There is no way I've missed that lot.. it's half mat and half silk... it must be drying too quick... I'll get a pole and water it down so it don't go off as quick.. and wait till its colder and maybe raining to give it another go LOL...

Use a thicker pile roller. Sounds like the roller is bridging the hollows.

well, ive done it again at weekend... got a new roller and a new tin of paint (same stuff) ...did it first thing Saturday.. let it dry, and a similar result !???
so set about it Sunday.. was going to spray it to try get it more consistant... So basicaly ended up diluting it a lot... Spray gun did not work well.. so ended up trying it with the roller... and issue solved !!??.... so it looks like it was way too thick.. and then drying too quick without maintaining the wet edge?....
My Dad was a painter and decorator.. and he says paint is not what it used to be?... that said he's 90 now so was used to the old stuff?.. anyway.. looks like i've overcome the issue?.. thanks for your input

What make of paint is it? I painted two bedrooms with Brewers own brand, extremely patchy with roller marks all over the place. 3 coats and it still looked awful. I bought Crown from B&Q and it covered pretty well with one coat and just fine with two. All matt emulsion. Cheaper too!

It’s Leyland... should be good stuff... but who knows?....