Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - John Pierce

Pages: [1] 2 3 ... 17
1
fyi, I sold this scope a few months back back to a fellow SCAC member to use as a grab-n-go SCT.

2
hmmm, said coulter has a 65mm (minor axis) secondary, so rough calculations suggest that with a 12" OD tube, plus focuser minimum height plus the 44mm flange distance of a EOS DSLR, I'd only get a 16mm diameter image circle before the image starts to darken significantly.    not good enough for an APS-C DSLR!! (which has a 28mm or so image circle)

3
so I just acquired a rather nice CI700 equatorial mount, this was a celestron branded 'cheapened' version of the Losmandy G11...   its a beast.  has alt and dec slo-mo motors but no goto.









I initially was thinking of using it for unguided piggyback as I don't really have a suitable scope for it, but now I'm wondering if I couldn't rebuild my Coulter 10" F/4.5 ... use one of Mark's Astrogoods alloy tubes, a better focuser than I now have, shorten up the tube enough that I can achieve focus with my DSLR (the secondary on the coulter is huge).  I have already replaced the coulter's primary mirror cell with one of Mark's creations, and the secondary spider with a curved vane spider from 1800destiny. 

http://www.astrogoods.com/atmparts.shtml

am I nuts for thinking this is a good idea?   the mount is rated for 60 lbs of instruments, 100 lbs total.   Celestron sold it with  C11 and C14 telescopes on it :-O


4
I posted this last year, I'll post it again,

Quote
stumbled onto this amusing Australian tv series, apparently it ran across Australia earlier this year.

the whole thing is on youtube, https://www.youtube.com/playlist?list=PLJLn8vIAKEr-slN8lPq4iCIpkVSMo2qZ2

Under the Milky Way is a 6 part (28 min each) Australian TV comedy/drama about an astronomical observatory in Coonabarabran NSW, thats being shut down because a fancy new larger observatory has opened nearby.     The whole thing was filmed on location at Siding Springs and Coonabarabran.

5
TAC Visual / Re: Solar Binocs!
« on: March 02, 2017, 09:53:30 AM »
oh yeah, I know all the precautions.     the felt tape I'm going to use should make them very snug.   plus  the business end is up in the air, so harder to reach...


6
TAC Visual / Solar Binocs!
« on: March 01, 2017, 08:13:04 PM »


those are 100mm binoculars, with the 14mm eyepieces, they are 42X

thats V0.1 ...   the yellow frames were 3D printed and not quite dimensionally accurate, so I need to do some tweaking.  I have some felt strips I'm going to add to the top and bottom so they fit more securely.    The ThousandOaks solar film wrinkled a bit when I taped it down, so I need to lift the tape, and trim the edges just a bit, then tape it down again.   Finally, I want to cover in black gaffers tape to reduce glare from the yellow plastic.    I might move the solar film to the front when I trim it.


7
TAC Visual / Eclipse Glasses for uber Nerds...
« on: March 01, 2017, 06:25:22 PM »


thats a pair of Hobart welding goggles, retrofitted with shade 14 50mm lenses (they come with shade 5 which is far too light for sun viewing).

coming soon, my optician said they can cut me my Rx onto 50mm circular plastic, and index mark them so I install them correctly :)   this should be good :)

actually, since taking that selfie, I've also shortened the bridge so they fit tighter to my nose and are parallel and not walleyed like in the pic.

and after the eclipse, I guess I could wear them to burning man!

8
TAC Visual / Re: Solar Eclipse
« on: February 11, 2017, 10:58:58 AM »
my friends who are veteran eclipse chasers all say, expect massive traffic jams on the morning of, and even the night before, as the unprepared urban masses jockey for position.

9
TAC Visual / Re: Solar Eclipse
« on: February 10, 2017, 10:02:09 PM »
I'm going to the Oregon Solar Fest in Madras, along with several other Santa Cruz Astronomy Club members.   We made our campsite reservations nearly a year ago, several of us have full RV hookups, several more are tenting it.    2 minutes 2 seconds of totality at our campsite.

the Oregon Solar Fest still has lots of camping, both RV and tent, at 'Solar Town' which is a huge field just north of town, near the airport (which happens to house an awesome air museum with a large collection of flying WW-II warbirds).   They are going to offer 'glamping' too, which will be fancy large tents already setup with queen airbeds inside, everything you need, just show up, camp a couple nights, enjoy the eclipse, and leave, they'll break camp.   

https://www.oregonsolarfest.com/

10
I thought I read the DNA Lounge was closing for good?!?  always sounded like a way cool venue, albeit most of their music isn't my thing anymore.

11
Forum stuff / fixed a dns registration problem!
« on: February 01, 2017, 10:31:01 PM »
I found and fixed a dns registraiton problem for the observers.org domain, so access to this forum should be much more reliable.   It was causing erratic DNS not found errors before.

12
Annual Star Parties / Re: GSSP 2017 Registration is open
« on: January 24, 2017, 01:05:49 AM »
Signed up!  Who else is going?  I expect I'll be staying out among the gas giants - Jupiter or Saturn.

me too, and yeah, likely saturn-to-uranus will end up being Camp SCAC :)

13
Annual Star Parties / GSSP 2017!
« on: January 22, 2017, 09:54:02 PM »
Coming Soon, GSSP 2017!    June 21-25, 2017, at Frosty Acres Ranch

http://goldenstatestarparty.org

14
Equipment Discussions / Re: solar finder ideas...
« on: January 20, 2017, 08:47:16 PM »
ah, my idea of a tube on a tranlucent disk has been done.


15
Equipment Discussions / solar finder ideas...
« on: January 20, 2017, 08:08:18 PM »
so thinking of the upcoming eclipse, I'm planning on making a safe solar filter for the club's 100mm binocular, which has 25x and 40x eyepieces....

It will need a sun finder, I'm thinking a brass tube, maybe 1/2" diameter and 4-6" long, with a translucent disc 1-2" in diameter superglued to the back... center the shadow of the tube on the disc as seen from behind, perfect.     this disc/screen probably should have a nice sharp black dot right in the middle

Whatcha guys think? 

I can use this mount I made for a laser pointer... 




the binos look like this, they are 45 degree, and take standard 1.25" eyepieces as long as they aren't too fat.   The 40X eyepieces are 14mm ES 82 deg. wide, similar to a Nagler, so the actual field of view is 2 degrees.



I'm thinking of finding some suitable cardboard, and taking a strip thats 6" x the outside circumference of the binoculars body, and using that as a template to cut a end piece, with 2 4" holes and thousand oaks solar film, assembled with gaffers tape :)      this should slip on and off the binos, if its too loose, I could always use wide blue painters tape to secure it.

Pages: [1] 2 3 ... 17