Heat

[doubleclix]

Hi All,

I'm just wondering, if I were to set up a telescope mid afternoon ready for observing at night, does it matter if the OTA heats up? On Sunday used my Newtonian to view the moon in the daytime, but the sun was beating down and the OTA got quite warm. Is this bad for the tubes?

Thanks in advance

Olly

[beachbum]

How hot are we talking about? Because I've brought my scope out mid afternoon plenty of times for collimation.

[lukebl]

My obsy got up to 40 degrees today! My scopes have been in there for around a year now and seem to be OK, suriving searing heat and temperatures below -12.

I do worry that it must be affecting my kit, although there must be astronomers using similar equipment in much hotter climates than ours.

[doubleclix]

It was fairly warm to touch, and the concrete it was on was too hot to stand on bare footed. Not as hot as today though (32oC)

[doubleclix]

there must be astronomers using similar equipment in in much hotter climates than ours.

Good point!

[Geno]

although there must be astronomers using similar equipment in much hotter climates than ours.

Never had a problem here in Cyprus, just the bugs and our cats to contend with.

[Moonshane]

I think the only issues would be rapid changes in temperature. e.g. going from a air conditioned house to searing heat, but even then I am not sure it would create major problems.

personally, I bring my scopes out and back in for every session and cannot see the point in putting it in the sun to get warm and then have to cool down again. I tend to put the scope in the shade (I am lucky maybe that my observing point faces east so the sun goes over the house well before I observe) so it's at a temperature closer to ambient more quickly.

[Ant]

If I am concerned about the tube heating up I quite often use a white T shirt to cover the tube and reflect some of the heat.

Cheers

Ant

[Adamski]

I left mine outside for the whole of april and detected no ill affects. The steel tube will expand and contract with differing temparatures but not enough to make any problems beyond tube currents and heat shimmer which you'll see anyway with your eyes.

[swamp thing]

Hi

I wouldn't have thought any scope would have any real problems as long as the optics are covered (you obviously don't want the sun on your mirror).

However equatorial mounts have lubricants in and when they are exposed to higher temperatures they tend to thin.

Possibly running off bearing surfaces and gear cogs.

It could leave the mount insufficiently lubricated.

So I would check these after prolonged hot spells.

It's always wise to check any mechanical device after any adverse weather anyway.

Regards Steve

[George]

Well it got to 45C in my observatory on Sunday, the PC auto shut down and there was spider carnage but the scopes as usual survived