mersenneforum.org

mersenneforum.org (https://www.mersenneforum.org/index.php)
-   Lounge (https://www.mersenneforum.org/forumdisplay.php?f=7)
-   -   The Unhappy Me thread (https://www.mersenneforum.org/showthread.php?t=7025)

ewmayer 2019-08-26 21:52

[QUOTE=lycorn;524624]A subtle way of letting us know you are currently on the Canary Islands, right?
Mind you, it is way dryer there than in mainland Portugal...[/QUOTE]

I would think the dryness would be highly favorable for Paul's astronomical pursuits there - Paul, is it simply a case of too much of a good thing? Maybe you just need a proper [i]Dune[/i]-style stillsuit...

xilman 2019-08-26 22:18

[QUOTE=ewmayer;524630]I would think the dryness would be highly favorable for Paul's astronomical pursuits there - Paul, is it simply a case of too much of a good thing?[/QUOTE]Yes and no.

Water-droplet cloud-cover is absent > 275 days per annum in a typical year. Saharan dust (la calima) cloud cover gets here largely because it is not washed out of the atmosphere en route. It's (water) cloudy here and now. The calima has been bad for at least a week.

High temperatures, and this summer has been and continues to be very unusually hot, is not conducive to the well-being of either humans or electronic equipment. 36 hours ago, for instance, I was testing stuff in an ambient temperature of around 35C. The camera's Peltier cooler could only reach -13C even when running full blast with an additional cooling fan operating. I generally observe with a CCD temperature around -18 to -20C as that's where the dark current starts being relatively insignificant. If the dome temperature is, say, 12-20C operating at -18C is straightforward.

kriesel 2019-08-26 22:23

[QUOTE=chalsall;524594]
I just hope the power stays on, so I can collect an empirical data stream from my tank sensors... :wink:[/QUOTE]No solar or battery backup?

kriesel 2019-08-26 22:29

[QUOTE=xilman;524631]The camera's Peltier cooler could only reach -13C even when running full blast with an additional cooling fan operating. I generally observe with a CCD temperature around -18 to -20C as that's where the dark current starts being relatively insignificant. If the dome temperature is, say, 12-20C operating at -18C is straightforward.[/QUOTE]What is typical temp for your tap water? Would liquid cooling the hot side of the Peltier help? Or introduce too much vibration (Slow flow is less turbulence.)

kladner 2019-08-27 03:33

[QUOTE]The camera's Peltier cooler could only reach -13C even when running full blast with an additional cooling fan operating.[/QUOTE]Any chance of getting a small window A/C unit (5000 BTU) to assist the Peltier? Depending on arrangements, you might have to duct the cool air in, or the hot air out of your work space, but still.....
I don't mean to imply cooling the space, just that piece of equipment.

xilman 2019-08-27 08:25

[QUOTE=kriesel;524633]What is typical temp for your tap water? Would liquid cooling the hot side of the Peltier help? Or introduce too much vibration (Slow flow is less turbulence.)[/QUOTE]Water cooling would help, as would dry-ice or LN2.

The engineering problems are simply too great. Try pumping cryogens around delicate electronic equipment which itself is being waved around all over the place. It can be done, and some cameras are designed that way but mine is not.

xilman 2019-08-27 08:34

[QUOTE=kladner;524642]Any chance of getting a small window A/C unit (5000 BTU) to assist the Peltier? Depending on arrangements, you might have to duct the cool air in, or the hot air out of your work space, but still.....
I don't mean to imply cooling the space, just that piece of equipment.[/QUOTE]I'd thought about it but it's not worth it.

Very high air temperatures are almost always a daylight phenomenon and the cooling can reach 45C below ambient. It is very unusual for the night time temperatures to exceed 25C and are usually below 20C.

Actually, it is very unusual for day time maximum to exceed 30C; this summer most exceptional.

A fan just above floor level in the dome pumps air 24/7 to keep the interior at close to ambient even when the slit is closed. It's to minimize thermal gradients which can distort optics and introduce turbulence.

chalsall 2019-08-27 13:31

God is a Bajan...
 
[QUOTE=lycorn;524600]Good luck![/QUOTE]

Where's the Kaboom! There was supposed to be an Earth-shattering kaboom![/Marvin the Martian]

So, the empirical supports the belief of some around here that God protects Barbadians... The storm veered North and passed *directly* over us. But we still only got ~18mm of rain over the whole night, and quite moderate winds.

I hope those next in line are as lucky!

Nick 2019-08-27 15:01

Glad to hear you're safe!

lycorn 2019-08-27 16:34

So, no kaboom, no boom, nothing boombastic after all.
Nice to hear the Barbadian gods (or goddesses, who knows?) have once again done their trick properly and youʼre all safe. :cool:

chalsall 2019-08-27 16:52

[QUOTE=lycorn;524670]Nice to hear the Barbadian gods (or goddesses, who knows?) have once again done their trick properly and youʼre all safe. :cool:[/QUOTE]

Thanks. A few years ago we had a tropical storm pass by us, and the winds were strong enough that 90% of the island was without power (and, thus, water) for over a week!


All times are UTC. The time now is 22:35.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.