The trials, tribulations and small triumphs of a Charlotte, NC astronomer imaging under Bortle 8/9 skies.
Tuesday, October 25, 2011
Deep Sky Imaging with the ETX 125
Last night was an excellent night for astronomy. The moon rose late and skies were dark and the seeing good. I mounted the ETX 125 in polar mode to see how it would perform on deep sky imaging. The answer is as I expected. GOTOs and tracking are excellent, from a visual point of view. However, the gears are just not built for long-exposure imaging and even 30 second exposures showed stars as streaks. I'll just have to wait until the 14 inch comes back before I can do more imaging work.
Aurora, Scopes, etc.
The aurora here in North Central Indiana was pretty short lived. It dropped from peak intensity about 5 minutes after I first saw it and faded slowly over the next hour.
In other news, the 14 inch is now on its way back to Meade. I hope I have it back by the first week of December, but I'm not holding my breath. There are some "horror reports" of scopes coming back from Meade in worse shape than they shipped out. I hope this is not the case with mine.
In other news, the 14 inch is now on its way back to Meade. I hope I have it back by the first week of December, but I'm not holding my breath. There are some "horror reports" of scopes coming back from Meade in worse shape than they shipped out. I hope this is not the case with mine.
Monday, October 24, 2011
Aurora!
We have aurora! Diffuse, reddish glow to the north; extensive. Elevation about 70 degrees at max, stretching down below tree line. Wow!
Saturday, October 15, 2011
Updates
I now have an RMA and shipping details from Meade for the 14 inch; I should be able to get it out of here next week for repair. The best guess is that it is a controller board issue for the RA drive. The good news is that it may only be away for three weeks, as opposed to six.
I have done a little more work on the 10 inch LXD-55. It seems to be behaving itself now and I may try some imaging tonight if it continues to work well. The LXD-55 mount is a German Equatorial mount ('GEM"). I'm not fond of GEMs, especially with a Schmidt-Newtonian (SNT) design, as the eyepiece of the scope can end up in some very inconvenient positions. Rotating the tube can help, but it is very inconvenient. I am also concerned about the drive itself. I disassembled it, refinished the gears and re-lubed it. The result was smoother slewing, better pointing and tracking, and less vibration. Whether the mount can support deep sky imaging remains to be seen.
I have done a little more work on the 10 inch LXD-55. It seems to be behaving itself now and I may try some imaging tonight if it continues to work well. The LXD-55 mount is a German Equatorial mount ('GEM"). I'm not fond of GEMs, especially with a Schmidt-Newtonian (SNT) design, as the eyepiece of the scope can end up in some very inconvenient positions. Rotating the tube can help, but it is very inconvenient. I am also concerned about the drive itself. I disassembled it, refinished the gears and re-lubed it. The result was smoother slewing, better pointing and tracking, and less vibration. Whether the mount can support deep sky imaging remains to be seen.
Thursday, October 6, 2011
The Moon, ETX 125
The moon tonight imaged with the ETX 125. The 125 is a great planetary and lunar scope, but I found deep sky imaging is nigh on impossible. This is a single image, 1/100th second captured at prime focus. The large, single crater at the top left is Tycho. Note the central peak and the white "rays" stretching for hundreds of miles.
The Sun in White Light
The sun today in white light. Single exposure, ETX 90 with solar filter. The leftmost spot is 1312; the spot to the right and below it is 1313. Further to the right and above is the small spot 1311. Faint, small spot on the right limb is 1305. The group of real interest is almost directly above 1312. It is group 1313 and it is crackling with C class flares.
It never rains but...
Latest update--Meade want me to return the 14 inch for repairs. Given the high cost of shipping, I bought Sky Assurance, which will give me 3 years of coverage for just a little more than the shipping cost. As Meade pays shipping under the insurance program, it's not a bad deal. The bad news--it takes 15 days to generate the paperwork for a return. Not sure how long they will have the scope, but it looks as if the Fall observing season with the new scope is completely shot.
One contact on an LX200 list suggested I remove the baseplate and take a look to see if a cable is wrapped around the gears. Apparently, it can happen. I'll take a look when I take it off the mount.
The backup 10 inch scope needs work. The cheapie plastic cowl on the Chinese GEM cracked in the cold last winter and fell off, damaging an encoder wheel. I've straightened it out, but the mount is still a mess. I rebuilt it completely and refinished the gears, but there is still an unacceptable amount of slop in the bearings. I'll see if I can get it working tonight, weather permitting, or I'll have to revert to the ETX 125.
One contact on an LX200 list suggested I remove the baseplate and take a look to see if a cable is wrapped around the gears. Apparently, it can happen. I'll take a look when I take it off the mount.
The backup 10 inch scope needs work. The cheapie plastic cowl on the Chinese GEM cracked in the cold last winter and fell off, damaging an encoder wheel. I've straightened it out, but the mount is still a mess. I rebuilt it completely and refinished the gears, but there is still an unacceptable amount of slop in the bearings. I'll see if I can get it working tonight, weather permitting, or I'll have to revert to the ETX 125.
Tuesday, October 4, 2011
M13
The lovely globular M13 has been described as looking like sugar spilled on a black table cloth. This is a single 30 second exposure on the 14 inch with CanonXTi. The bad news--this was the last pic i took before the 14 inch scope started to have RA drive problems. I have a feeling I might have an expensive shipping bill coming up, as well as some weeks of waiting for the scope to be fixed. I should know more tomorrow.
Ring Nebula
M57, the Ring Nebula imaged on the 14 inch with a Canon XTi. It is a stack of 6 30-second exposures. The central star is just visible in the ring. The nebula is not really a ring, but we are seeing it 'front on." It is probably more like a cylinder. The central star is reaching the end of its life, and this image may well be how our sun will look some billions of years from now as it enters the final stages of its life and puffs off its outer atmosphere.
Albireo
Albireo (Beta Cygni). The color difference between the bright yellow star and its fainter, blue companion makes this one of the "must-see" sights for any star party. 4 stacked 30 second exposures, LX200 14 inch ACF.
M92
Single exposure image of M92, globular cluster in Hercules. Nikon D40, 14 inch LX200 ACF. Globular clusters are made of old stars. Their is no associated nebulosity as it has nearly all been used to form the stars in the cluster. Ols stars like this are called, "metal rich." Although their are atoms of metal elements in these stars (and metals accumulate as stars age), the term is misleading. In astrophysics, anything that is not hydrogen or helium is classed as a metal.
C/2009 P1 ( Garradd )
This image is a single, one minute exposure showing C/2009 P1 in the center of the field. Pic taken with LX200 ACF 14 inch and Nikon D40. Note the blue/green color of the comet, and the nebulosity surrounding it.
Monday, October 3, 2011
Observations of Sunday, Oct. 2, 2011
A very good evening for observing with the 14 inch. Found C/2009 P1 (Garradd). Its position is a little different from that in the IAU Minor Planet Center ephemeris, but only by a minute or two in declination. The comet seems a little fainter--about +8.5. Sky contrast was quite good and I thought I could make out a faint tail. Looked at some of the old standy objects: Albireo, M13, M92, the Ring Nebula (which was wonderfully visible, floating almost in 3D against the background of space. The Dumbell Nebula was also beautiful, with the dumbell shape clearly visible.
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