Shopping for small refractor

I haven't posted in a while. I've been in Massachusetts for about two months and the weather has been unstable. When mild it's been gray. When clear it's been frigid or the moon has been out.

Meanwhile I'm in the market for a cheap short focus refractor to ride piggyback on the C8 to take wide field deep sky images. Short focus refractors come in a variety of sizes and and prices but I was looking to go cheap skate without too much compromise.

As luck would have it, while watching a YouTube review of the Celestron Nexguide  auto-guider the reviewer mentioned his satisfaction with using a piggyback mounted 70x400 mm Celestron Travelscope as a guide scope. At less than $100 I figured the scope was worth investigating.  Celestron also offers a piggyback mount that mates to several of its scope models.

One  Travel Scope Amazon review included some pretty decent astroimages taken through the scope by the reviewer. Suddenly I was seeing this scope as a credible candidate for a wide field imager. I probably should have bought the scope right after Black Friday when it was as low as $65 from at least one online vendor. Demand for the scope as a Christmas gift caused the price to soar to $90 - $100  going into Christmas until settling to a low of $75 today. I've been holding out hoping a vendor will blink to a lower price but will get one by  Spring.

Recent DSO Images

The marriage of the Meade DSI, the C8 SCT and the Advanced VX mount is finally starting to pay off. All of my DSO imaging is done unguided. I do perform a two star align followed by four star calibration with an all star polar alignment (ASPA) on a star near the meridian. This is usually enough to give me nice round stars for less than 30 sec exposures unguided.

All images were acquired using Meade Envisage software in FITS file format. NASA / Fits Liberator 3 freeware was used to extract and enhance  R, G and B TIFF files. Paintshop Pro was used to colorize the TIFF files, apply touches to remove blemishes and to recombine them by merging layers.

                Comet C/2013 X1 PANSTARRS

NGC 884 -- Open Cluster

NGC7635 -- Bubble Nebula

NGC869 -- Open Cluster

NGC457 -- Owl Cluster

NGC7331 Spiral Galaxy

Cold night. Bright Open Clusters.

The plan for 1/11/16 was to acquire images of  open star clusters M35, M36, M37, M38, NGC1664, NGC2129, NGC2158 and M78. Only M35, M36, M37, M38 and NGC2129 yielded pictures worth processing.  Images were acquired by averaging 25 to 50 8s exposures. Celestron SCT8, Celestron 0.63x field flattening focal reducer, Antares 0.5x focal reducer. Imaging was done using Celestron AVX mount using 2+4 star alignment and ASPA (all star polar alignment). Otherwise imaging was unguided. 

Images were acquired in LRGB FITS format. Fits Liberator freeware from NASA/ESA was used to extract the red, green and blue TIFF files and make adjustments to bring out faint stars. JASC Paint Shop Pro 9 was used to colorize and merge the R, G, B layers to get the final images. 

M35

M36

M37

M38

NGC2129

AVX Repaired

This post is about a month after the AVX was returned from repair. I left off my last post saying I was fuming at Celestron.  Kudos to Celestron for fixing my AVX  two weeks faster than expected. 

OTOH, I was not notified by email that the AVX had been shipped. It arrived on my doorstep a day after I returned from a month long trip no signature required. What if I was still away? Theft of shipped goods from peoples' doorsteps have become a common crime.

Also annoying is I emailed the Celestron contact about what was the nature of the failure and if there was anything a user could do to prevent it repeating. I got no response. That said I greatly appreciate the expeditious way Celestron handled the repair.

Celestron AVX on the Fritz :(((

Did I neglect to mention that my Celestron AVX mount is on the fritz? The drive is only a year old and at the worst possible time, a clear August night in Harvard, MA, scope setup rough aligned with Polaris I hit the on switch and nothing. I checked the fuse in the 12v cigarette lighter plug and it was burned out. I replaced it and still nothing.

I called it a night and when I got home emailed the Celestron AVX Yahoo group for advice. The quick answer was there's no internal fuse. The drive's likely died. WTF?

Contacted Celestron and arranged for a warranty return. Celestron warranties are two years. I hope the Discover card automatic 1 year extension* also applies because this sudden failure does not give me a lot of confidence in Celestron's manufacturing care. Celestron advises repairs take a minimum of six weeks. That really sucks. Meanwhile, here in Maryland, a state not known for clear skies we had had about ten days of clear, low humidity pre-Fall skies.

I'm fuming with Celestron.

*Discover has since taken away this benefit. That really sucks. 

Comet Lovejoy

Tonight I took a chance I could see Comet C/2014 Q2 Lovejoy from my 3rd floor patio. I rarely image from my patio because the sky is mostly blocked by trees and the overhang of the patio. Because the altitude of the comet would be about 60 deg I needed to get the C8 AVX setup early and the Meade DSI equilibrated before the comet was hidden by the patio overhang. I used the AVX Quick Align and syncing on Aldebaran since Lovejoy was in Taurus. I was able to cool down the DSI using the optional fan and collected some quick dark frames between 1s and 15s  around 1C. The comet is surprisingly bright and was able to image with a series of 5.7s exposures. I only accumulated about 10 frames. The result appears below. If I'm lucky I'll get to my local park site and get a better image later this month.

Celestron AVX + Meade DSI -- part 2

This blog is about the Meade DSI which I've had since 2011 using with both enjoyment and frustration. In recent years my frustration has been with stubborn CCD hot pixels that persist despite being subtracted by dark frames.

Based on a comment by another DSI user I have started only acquiring dark frames for the exposure time I will use for the next target deep sky object(DSO). This saves time and ensures fresh dark frames for each new image acquisition. DSI will complain if there is no 1s exposure dark frame for the current temperature. Thus I collect dark frames between 1s and 8s. 

All of my imaging to date has been unguided as I have not been willing to invest a second imager, scope, etc needed to automatically guide the mount. That said, the AVX mount tracks beautifully even without periodic error correction(PEC) training.

One of the really great features in the AVX is the "All Sky Polar Alignment". After doing a two star alignment and refining go-to accuracy with four calibration stars  you can refine the accuracy of the polar alignment by pointing to a star near the meridian and following the All Sky Polar Alignment procedure. The procedure saves a ton of time compared to the drift alignment method 

My most recent imaging has been in Maryland where clear nights have been few the last couple of weeks and seeing has sucked. In any case a few images will be shown in the next post(s).

Also, because of the small size of the Meade DSI CCD chip I use a fairly aggressive focal reduction strategy. I always keep an Atik 0.5X  focal reducer screwed into the DSI. This also serves to protect against dust. I also have a Celestron 0.67 field flattening focal reducer for more extended targets such as M42. As will be seen in part 3