Looks to be a crater in the center of some of your spot welds.
If so, You need either to turn up the wire speed a bit or hold the trigger for a moment longer to fill the crater that forms in the center of the puddle.
Can't see, put a cheater lens in your helmet, makes a world of difference for old eyes. It makes things brighter for my old eyes. Another trick Shine told me was to put a spot lamp shining on the weld zone, and it does help.