Yeah, you were all right. I just managed to get to my sensor for real this time and can see the spec of dust on there. Previously I think I was just looking at the mirror… Does it show that I’m a newbie? haha.
Well, I tried to blow the dust spec away with a blower thingy, but that didn’t work. Considered using compressed air, but the internet said not to. So now I’ve ordered a sensor cleaning kit.