Monday, February 07, 2011

warm 'em

I guess I haven't observed in the winter or extremely cold situations for a while. So I'm a little frosty...

Sorry. Sorry about that. It was right there! Come on. I couldn't not take it...

Rusty. I was rusty.

I couldn't remember whether I should warm eyepieces or keep them at ambient temperature. But I did experience minor hazing issues when I was keeping them outside, under a towel still, but at cool temps. As I would look through the eyepiece for a long time, I'd see a halo appear around bright objects. It was dew or frost from my body. My eyeball was heating the glass! I also had to be careful not to breathe on the ocular.

But after some net stumbling, of course, I realised / remembered / recalled / undersood that you have to heat the eyepieces. As you do in the summer, you do in the winter. Duh!

So, I should have kept the eyepieces in the warm room of the GBO.

I asked Dietmar if we had an eyepiece heater and was not surprised by his answer. A little disappointed though. So, in the meantime, it will be the low-bandwidth, simple solutions required: keep eyepieces in pockets. A little more challenging when you have 5 layers on.

Then there's the issue of the Tele Vue refractor. Without an objective heater, the telescope might not be usable... I'll need to look into that.

Or, one could just persevere as did wimmer, as he noted in his ASOD entry.

That's a photo by wimmer of his Celestron 5" SCT on SLT mount. He said the temperature was around -20°C. Incredible.

And that's the photo I snapped of the objective cover for the C14.


SciDomer said...

Here's a crazy idea for a new winter observing accessory. All that hoarfrost is only there because of exhaled breath. So all we need to do is bring snorkles to keep our breath away from our lenses and out of the optical path.

bla said...

Combined with the eye patch over one eye, we really will seem pirates!