Yes, I know they ain't straight and yes I've patched the old holes with masking tape and will paint over them . It's a quick and dirty temporary solution (honest)
I had 6 holes (possibly a little bigger than them) in my living room ceiling after removing some old downlights. Filling them was surprisingly easy and didn't take much time to do.
If you can get up in the loft above stick some old plywood or mdf over the holes with a bit of grab adhesive (brush away any dust first). You want a fairly oversized bit that goes well over the edges of the hole so once it's dried you can blast a few plasterboard screws through the ceiling (from the room upwards) to fully secure the wood. If you can't get into the loft, take a piece big enough to do it from the loft and cut it in half so it's small enough to be slotted through the hole from below. You can hold the first piece in place with you hand through the hole while you screw it in from underneath. Drill a screw into the centre of the second piece (before putting it through the hole) so you can pull down on to it while it's being screwed in.
Then just cut a chunk of plaster board to fit the hole and screw that to the wood filling most of the hole, then get some filler and fill the gap between the plasterboard disc and the original ceiling (fill it slightly short of level with the ceiling). Then skim over the surface (any any screw holes) with some easy fill to get it perfectly level. Spray a bit of water on the final skim and give it a final swipe with a trowel to get a super smooth finish that barely needs sanding.
Dave
