Yeah, and most of their eyes are pretty much specialized for movement and probably don’t see in any detail. As mentioned, jumping spiders have two large eyes that see reasonably well, and may see color. Spider vision seems to dip into the ultraviolet range. Some species are extremely vivid in the UV spectrum on their carapaces, and it is thought to play a role in sexual selection.
To be fair, I wasn’t calling the OP an idiot. I was calling whomever told the OP this an idiot.
Guess who is totally off of my Christmas list right now?! If you’ll excuse me, I’ve got to finish constructing my life-sized hamster ball now.
thanks. though there are many times when I qualify!
But the person who to me the story wasn’t advocating it, just repeating what he was told by the person who was in fact painting his garage wall blue. So the person doing the painting is the one who reaches the threshold. 
Thank god I’m not the only one who thought this.
**I have to reply. Someone mentioned this at work about painting the ceiling sky blue will keep spiders away.
So my boss gave me the challenge since we have so many different kinds of spiders in out substations.
Presently we have painted one substation ceiling sky blue. It has been three days now since the job was completed. Honestly, after checking today, The ceiling is pretty- clear of any new nests, but they are everywhere else.
I think that it will have to take more time to test the test.
I do not know anything about spiders other than they can be aggressive especially these big black fussy ones. I spot most of these types behind large air handlers where very limited traffic takes place.
Now back to the blue paint. I will check this one experimental substation on a daily basis and will report back of my findings and let you know if the blue paint works.
**
**
we had decided to try this at our plant inside one of the substations. It looked real nice with our painted floors. However, after a few days, I passed by the substation in route to one of my other many tasks, looked in and sad to say the spiders have returned to the ceiling. So whoever started this rumor, forget it, It does not work> Hoever, I did recall reading another post indicating the use of lemon pledge around doorways and windows. We are going to order a few cans of this and try it. Guess that spiders do not like lemons for some reason. We will see how that works and report back at a later date.
**
The Frankfurt kitchen plan from the 1920s specified a teal blue for cupboards and countertops “because research at the time suggested sky-colored surfaces would resist bugs (if only).” 
The reference I heard originally was to flies. They’re superb at seeing motion, but do they react at all to color?
This is related to the ‘haint blue’ question in this thread. The last post in that thread is the answer to this one.
They used to mix up the haint blue paint using lime, and that is supposedly also what kept spiders from building webs on the blue-painted surfaces.
I’m going to guess the reason you didn’t have spiders at first was either off gassing from the paint (or that the paint was still wet/tacky) or just the fact that you had cleaned it three days prior. To do a proper experiment, paint another area a different color and see how long it takes and in yet another area just clean all the webs away and see how long it takes for them to come back. You may find that in all three cases it takes about 3 days for the spiders to start coming back in. Or you may find that it takes about 3 days post painting (any color) for them to come back.
Also, don’t forget, spiders don’t know how long it’s been since they’ve occupied an area. If you get rid of all the spiders in a room and do nothing else, they might show back up 5 minutes later or not for 3 weeks. You would have to take that into account as well.
It’s like when someone’s grill gets clogged with spiders webs and they mention that they just got the grill last month. Well, spiders don’t go looking for 8 year old grills to nest in, they just find any propane source.