I'm living in California near L.A. area and the weather suddenly got cold for last few days (45-55 when I was out).
I cooled down my scope for at least an hour and a half. I was looking at Moon and Jupiter and guess what. They were 'boiling'. Or shaking.
First I was thinking it was the heat that obstruct the viewing because the temperature difference from high to low was about 30*.
But it was around 10pm and I was looking at Jupiter high in the sky. Should it not be affected by heat then?
The next thing came to my mind was the optics. I looked into the primary mirror and no dews were visible. BUT when I closely looked into the primary, I could see rainbow color sprinkles (I can't explain any better) were visible on the reflection of the inside of OTA through the primary. By directly looking at the inside of OTA, no 'rainbow color' was visible so I don't know if the reflection in the primary was just because of the mirror or was actually 'invisible' light dews. (by the way, the dew point was nearly 20* according to weather.com and it was around 45* when I was out.)
I was fine with views until the last week when the weather was not cold as it is now. I'm thinking it is related to the cold weather.
Anyone can explain what it is?
The problem is not really noticeable on these pics but I'm attaching two pics of Moon. One was taken last night and the other one a month ago. Both were taken with same device (iPhone 5) and focused to its best under the given condition. If you see the edge and details of craters, you will notice how bad the condition was on last night's pic.