Leaving astronomy gear in a hot car

[Paz]

With the holidays approaching I am thinking about what grab and go set up to take on holiday. I've always made a point of never leaving astronomy gear in a car in the daytime in case it gets too hot and something gets damaged but I'm not sure if that will be possible this year.

Has anyone any knowledge or experience of how heat can damage things like scopes, eyepieces, rubber bits, greases/lubricants on mounts, etc or am I worrying too much.

 

[Carbon Brush]

The short (and unhelpful) answer is that it depends. The longer answer follows...

I have wrecked spectacle lenses by leaving them on a car dash. But that is plastic lenses with a dodgy coating. Proper glass scope lenses should be OK.

The rubber used around eyepieces, etc should be OK. The same goes for neoprene type rubber used in O rings.
I have some (cheap) traffic cones made from rubber. They used to be really smelly when the sun was shining - the rubber degrading on UV or heat.

The plastic that is increasingly being used for trim and finish, as well as for structure,  on scopes, is a different matter.
I strongly suspect that if exposed to 50C and higher it may change shape and not recover fully.
It will be interesting to see how these scopes hold up to a few years of use.

Will any vapours from degrading rubber or plastic deposit on optical surfaces? I don't know.

Grease should not dribble out of mechanisms - if it is the right grease.

However, we all know that a lot of the better named products are often sub contracted to China manufacture.
When the known name is not looking, can you say they did not use the '£1 less' ingredients?

Depending on your holiday arrangements, you might be able to help with chilling the kit. For example, I used to store films in the fridge.
I have always done the same with underwater cameras to avoid housing condensation when entering cold water.
Wrap your scope or binos in a (not too sandy) beach towel when you park the car.
Keep an ice pack in your scope kit box.

My observatory gets quite hot, having a black roof. Kit has been in there for a few summers and I have not seen any problems that could be blamed on heat.

I hope you get some responses from people more knowledgable in these matters.

Hope this helps. David.

 

[DeepSkyBagger]

My telescope lives outside in one of those large plastic garden equipment storage things. During the recent hot spells, being in the direct sunlight, the temperature in there frequently exceeded 45 degrees. I was a little concerned, so I opened the box up during the heat of the day - though this frankly did little to reduce the temperature.

My scope is a 12" SkyWatcher Flextube with Synscan handset. I used the scope several times during the heatwave, and I found no problem with anything.

I don't image, so I have no delicate imaging equipment in there, so I can't say anything about how that would be affected.

[chiltonstar]

I've had optics damaged in a hot car due to material outgassing from plastic components and ending up on the optical surfaces. This would depend of course on how much plastic was in your kit?

Chris

[Jeff-Colorado]

I take my 8 SE out on camping trips and leave it in our car during the day when it gets as hot as 95 degrees outside. It is not in direct sunlight and is inside a padded bag.

I've had no collimation issues with it at all.