Posts Made By: Darlene Fung

Hi Gang,

Go to this web site for observation tents made in Canada that incorporate design recommendations from members of the Royal Astronomical Society of Canada. It uses a special frame system that is quick to set up. Unfortunately, the cost is not posted. I doubt if it is cheap but the tents look promising.

Go to: http://www.telusplanet.net/public/northpc/Home.html

Clear Skies,

Darlene

To Dan, James, Floyd and Larry,

Thank you for your replies!

OK, let's see if I understand things.

While the Google poster's laptop requires 18 v at 4.2 amps when charging and 1.4 amps when running, my laptop requires 16 v at 3.75 amps when charging. Per the AC adapter, the output is 16 v up to 3.75 amps. Input 100v-240v ~ 1.4 amps. Does this mean that the laptop requires 1.4 amps to run?

So, if I'm using a DC/DC converter with an efficiency of 85% and allowing for a 5% 'headroom,' my 12 v 18 AH battery will power the laptop for about 8.04 hours. Correct?

Here's how I got the answer: 16 v X 1.4 a = 22.4 watts. 120% X 22.4 watts = 26.88 watts. 26.88 w / 12 v = 2.24 amps. 18 ah / 2.24 a = 8.04 hrs.

But another question pops up. What happens to the laptop's own li-ion battery while I'm running the Fujitsu with the 12 volt 18 AH battery? Is the Li-ion battery being drained and charged to some degree too? And if so, are these amounts negligible? Does this also affect how long the 12 v 18 AH battery can power the laptop significantly?

Thanks for your comments.

Darlene

James,

Try contacting Mike Palermiti of ITE. He might be able to help you but be sure to check the cost for the repair.

http://www.iteastronomy.com/about_us/index.php?tid=7

Good Luck,

Darlene

Bev,

Check out the Better View Desired web site which has extensive reviews of binoculars suitable for birders. The link below will take you to a review of the Pentax DCF SP series binoculars that are nitrogen-purged. They also have hydrophobic coatings on the exterior lens. Be sure to read the other reviews of binocs that are nitrogen-purged as it is suppose to limit fogging. Here's the link: http://betterviewdesired.com/Pentax04/index.html

Good Luck with your search.

Darlene

Ron,

I prefer the image on the right as it looks more natural to me. The one on the left looks like a blue poster cut-out figure due to the flatness and lack of tonal range.

Also, I want to thank you for your many postings, comments, web page info, etc as they are terrific reads.

Looking forward to your images, comments and what-nots regarding Mars.

On Aug 5th, I had a chance to observe a phased Mars and was able to observe the SPC, grayish darkening in the Southern Hemisphere, the AM limb arc, and a bluish something at the Northern Pole. Scope: AP130 f/6.

Best Regards,

Darlene

Guys,

Thanks for the interesting reads and some great suggestions. I don't think the owner of the property would take kindly to paint on nor steel stakes in the concrete.

While there are no setting circles on the alt-az mount, I can use the compass to take a reading of a near- by bright object relative to the faint fuzzy I'm trying to locate. Thank you Randy and Rod.

But I was still curious as to why my compass was outrageously off the mark. The noaa web site said the declination for Oakland is 14 degrees 46" East so I adjusted the compass accordingly. Mars was still way off.

Using Buck's suggestion, I said to heck with what noaa says, pointed the compass at Polaris and adjusted the declination to whatever would bring its alignment marks together (Brunton Eclipse). Then I adjusted the bearing to the reading Starry Night gave me and found Mars to be where the arrow was pointing! Hooray!

Curiously, the compass shows the declination is about 17 degrees East. This variance could be due to some magnetic interference in the area.

By the way, starry night's companion book say the azimuth reading follows the land based horizon co-ordinate system.

Clear Skies!

Darlene

Ron,

Nice pix. Your astrophotos get better and better.

Clear Skies,

Darlene

Ron,

Another nice pix. I agree with you about the seeing. What a revelation it was for me the other morning.

Clear Skies,

Darlene

Filters for astronomical use also share a similar condition with photographic filters. This has to do with 'factors' and how much light they block. The higher the factor, the darker the shade of color the filter has.

As you increase magnification to high levels, the image starts to become 'dimmer' and thus starts to become less tolerant of increased factors. This becomes more important as you try to tease out the very subtle albedo shadings.

What this means is that one filter with a factor of 'X' will be great at 'n' magnification and not so great at 'n X 2". Thus, with my 5" refractor, I was cycling through my Baader Contrast Booster, FL-D, #85 and #82A for the best views of the albedo. For the seeing and mag (195X - 260X) I was using, these worked the best out of a collection of 21 filters and 1 mm stepped orthoscopic eyepieces with a 1.8 barlow (7mm, 6mm, 5mm, 4mm, 3mm).

Since you are using a 8" scope with a different range of eyepieces and eyepieces with different lens configuration, your milage will vary.

To get a nice range of filters, go to a specialty art supply store and pick up samples of color transparancies if they have them. Then you can experiment with them by holding a sample in front of the eyepiece when viewing Mars or any other planetary object.

Hope this helps.

Clear and steady skies,

Darlene

Hi to all,

Thanks for your comments and feedback. The caveat about dew is well taken as I live where fog creeps in. Still, knowing Scott found no visual difference between the Maxbright and Van Slyke's Hex 2" is encouraging.

Clear Skies,

Darlene