Posts Made By: Charles Stevenson

Edit #1: I found the threading it says right on the product page - "M42 thread on extension tube" *slaps forehead*

Original post:

I have a Celestron 80mm Guidescope #52309 mounted on my C8. I've read that for astrophotography it's best if the camera is screwed onto the scope rather than connected via tubes with retaining screws (don't know the nomenclature offhand). I removed what I think is called the visual back from the focuser to remove it from the equation. The focuser silver tube has threads on it. They're not SCT thread as my corrector reducer doesn't fit (the diameter is smaller... maybe it was 1 3/4"? I'm at work and didn't bring in the measurements). Does anyone know what the threading is? Has anyone used this scope with a guide camera and or taken photos through it?

http://www.celestron.com/browse-shop/astronomy/astroimaging-accessories/guiders/80-mm-guidescope-package

Wondering if anyone else has experience with this focuser? Just ordered one and should have it later in the week. The William Optics 2" dual speed rack & pinion SCT focuser sports a digital display gauge and builtin thermometer.

I'm having some issues with threads getting stuck. It may be due to temperature changes. The first time my Celestron f/6.3 reducer got stuck to my C8 SCT. I had been viewing outside in 0 degree weather and came inside. I thought perhaps it was due to the metals expanding differently. Then the other night I was viewing again and my Celestron 2" diagonal got stuck to the Celestron reducer (on the 2" side this time).

It took some large clamps and wrenches to loose them. The first time the teeth from one wrench left marks in the reducer. I had tried to protect it with some fabric but perhaps some leather or rubber would have been better. Last night I tried leaving the reducer and diagonal outside in the low temperature air all day in hopes that at lower temp I could separate but no luck so it was back to the tools.

How can I prevent the threads from seizing up on my equipment? :S It's very frustrating and I don't want to damage anything. ~ Charlie

Edit: Does this look like it would do the trick https://mercedessource.com/store/anti-seize-compound-use-critical-threads-screw-lid-container

I was very casually looking at the moon tonight. I just sort of opened the curtains on our East-facing window... I didn't feel like going outside... too cold... too much effort. There's a fair amount of ugliness to the images through two panes of glass but the moon doesn't seem as sensitive to that as Jupiter does. So I was just looking... taking it all in... enjoying the moon... then all of the sudden I thought there was a spec or something on my EP. And then it was moving and some microseconds into this my brain recognized what was happening. A jet was flying in front of the moon (of course it looked upside down too). It made it from one side of the moon to the other in short order. Perhaps a second or two. First time that's ever happened to me and I thought it was pretty cool. The wife and daughter didn't seem as impressed. Anyone ever had that happen? I suppose the plane was on its way to Boston which is 50mi or so East.

We watched a video of a talk by Mike Brown tonight during our weekly Aldrich Astronomical Society meeting. Being new, I found it really interesting that Pluto has been downgraded and learning all about the Kuiper belt.

http://youtu.be/mSWuyB2o_3E

IXV looking good! Pano photo from Park Ave in Worcester, MA birthplace of Robert H. Goddard... in city for training today

"The target trajectory for separation of the Intermediate Experimental Vehicle was a perigee of 76 kilometres (47.2 miles, 41.0 nautical miles) and an apogee of 416 kilometres (258 miles, 225 nautical miles) at an inclination of 5.4 degrees."

"While this could technically be termed an orbit, since the perigee of the trajectory lies above the surface of the Earth, it intersects the atmosphere such that the IXV will reenter before completing its first revolution."

"Such a transatmospheric orbit is generally considered to be a suborbital, rather than orbital, mission."

http://www.nasaspaceflight.com/2015/02/europes-vega-rocket-debut-ixv-spaceplane/

I think I just saw a fireball! At least, it was the brightest burning and falling object I've ever seen at night. How would I see if anyone else had a sighting of this? It was in the vicinity of Hercules from my house looking East towards Boston.

This might seem a bit like a child's crayon art but I managed to get my first deep sky image tonight. It was bloody cold outside!! My filter wheel decided not to work in the cold. I took it inside and it worked fine when it warmed up but again displayed mechanical error when it got to temperature outside. I accidentally shattered the mount bracket (plastic) on my red dot finder and had to dig out my ol' finder scope. Did I mention it was cold?

Anyways, gave up imaging with the C8 and just used my ATIK 16IC that I had intended for guiding. I was able to hone in on NCG 3034 cigar galaxy. I took all sorts of exposures. I don't think I was focused but it was too cold to fuss with it. I'm very excited nonetheless to have something to show after two months of reading and tinkering.

This is made from a single unguided 30 second exposure with 2x2 binning using Artemis capture that came bundled with the camera. I processed it in IRIS v5.59. I had experimented with stacking it in Registax, AutoStakkert!2, and Astroart. I didn't find the stacking helped any with this particular session. *shrug* Better luck next time. =) Now i need to jb weld my red dot finder.

I uploaded it into http://nova.astrometry.net/ and it was cool to see that it correctly identified the image.

I dragged the scope out again tonight. I was finally able to image with the Basler A102f through the C8! I recorded via FireCapture into AVI format about 19s worth and stacked with AutoStakkert!2. f/6.3 focal reducer to help it all fit.. It was in the vicinity of my chimney so I'm actually quite amazed at how the stacker was able to make it all work...

Full size lossless image here (in case this one is too small): http://charleskelleystevenson.com/moon_Moon_250215_200520_g3_ap1_conv.png

Edit: oops... forgot to flip it so it's how it should look to the eye. sorry ;(

I can report great success with MetaGuide! I actually inverted my intended setup and was guiding with my C8-mounted Basler firewire camera via MetaGuide while imaging through my 80mm guidescope with my Atik 16IC. This is my second deep sky attempt. Much better results than last week's M 82 first go.

I imaged M81 entirely unfiltered mono since my filterwheel was already attached to the Basler and I didn't want to rebalance yada yada... I was easily able to do 5 minute exposures with MetaGuide locked and guiding... I might have been able to get more out of it but I didn't try. Rough polar alignment was done beforehand. I started stacking and processing in DeepSkystacker. 15 x 300s 1x1 bin.

What do you think? This is the first time I've seen a spiral galaxy through my own doing. Very exciting ) Something streaked across one of the subs but I thought it looked cool so have left it in thusfar. My stars are somewhat bloated so might have to shrink them.

=== Sample of FITS header from tonight ===
SIMPLE = T
BITPIX = 16
NAXIS = 2
NAXIS1 = 659
NAXIS2 = 494
BZERO = 32768.000000
BSCALE = 1.000000
DATAMIN = 0.000000
DATAMAX = 65535.000000
INSTRUME= 'ATIK 16IC: fw rev 1.07'
EXPTIME = 300.002
DATE-OBS= '2015-02-28T09:35:30'
XPIXSZ = 7.400
YPIXSZ = 7.400
XBINNING= 1
YBINNING= 1
XORGSUBF= 0
YORGSUBF= 0
XPOSSUBF= 0
YPOSSUBF= 0
CBLACK = 4989
CWHITE = 31398
SWCREATE= 'Artemis Capture'
END

~ Charlie