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“Stars & Scopes” A Stargaze Short Timer’s Report

This year’s edition of the Mid Florida Stargaze was held from March 7-10, 2013 in Venus, Florida. Why do we love to go to Venus for a Stargaze event? To paraphrase the old saying, two pictures are worth 2000 words! In Fig. 1a.) below, you see an unprocessed (JPG) 60 second exposure taken just before Stargaze from my back yard in Tequesta (just South of the location of our monthly Jonathan Dickinson (JD) observing sessions. A hint of the Flame Nebula (NGC 2024) next to star Alnitak in the end of Orion’s belt has a difficult time competing with the local light pollution sky glow. In stark contrast, Fig. 1b.) is a 120 second exposure (twice as long as in the previous figure) taken on the first night of Stargaze (with the same camera and Short Tube 80 telescope as used in taking the Tequesta photo). In this case, the minimally polluted dark sky makes it easy to take a longer, sharper photo. This is a graphic comparison of why we love to go to Venus for a star gaze!

1a.) 60 second exposure from Tequesta

1b.) 120 second exposure from Venus

To take advantage of these fine observing conditions, I set up one of what I affectionately refer to as my “shoestring astrophotography” setups, collected 7- 120 second exposures using an entry level Canon DSLR (Rebel XS) and used a Short Tube 80 refractor that I had acquired via Craig’s List for only $90. I used a modified attachment to the drive of an early model Nexstar 8 for pointing the camera-OTA combo (this model mount is not noted for accurate tracking, being recommended for visual observing only and was un-guided by either electronic feedback from another detector or by the operator). Preprocessing, stacking, and some post processing were accomplished using Nebulosity 2 and then further post processing with Lightroom 4 and Photoshop Elements 2. The resulting image is shown in Figure 2. I was delighted with my best Flame and horsehead nebula result to date. While not a world class image (the slight streaking of some of the peripheral stars is undoubtedly due to the Alt-Az tracking configuration, rather than the preferred equatorial (wedge mounted) mode of operation. The resolution of an inexpensive 80 mm f/5 refractor is another limitation, but our family fridge doesn’t seem to mind these limitations of this best to date “shoestring” photo.

2.) 7-120 second exposures from Venus -- stacked, processed, enhanced, and cropped


“Stars & Scopes” A Stargaze Short Timer’s Report (continued) What else happened the first night of Stargaze 2013? It started with a search at twilight for the much anticipated entry of the Pan-STARRS Comet into the Northern hemisphere. There was a false alarm (captured in Fig. 3) called to everyone’s attention by one of the participants, but it turned out to be only a distant con trail. No success with Pan-STARRS was to be had on our first night in Venus. For reference, a lucky capture from the tower location within JD a few nights later is shown in Fig 3b.)

3a.) Comet Pan-STARRS False Alarm

3b.) Local (JD) 13 March capture

From my own perspective, the success in Venus was short lived. After capturing the image data for Fig 2, I returned from viewing one of Jay Albert’s 11” observations only to sit down wrong on my observing chair, lose my balance and knock over my observing equipment as I went down (seemingly in slow motion), as well as a display tripod. The result was that the mount tripod leg and a display tripod leg were broken – which generally put me out of commission (camera status was unknown at the time, but no permanent damage seems to have been done). Rather than chance further damage to other gear, and to allow a better prepared trouble shooting and potential repair situation, I decided to become a “short timer” at this year’s Stargaze and returned home the following day. In the better news category, after a few days of careful repair and assessment of the “lessons learned” with my apparatus and setup in Venus, I was able (on March 15th) to capture the data for my first “shoestring astrophotography” image of the Rosette Nebula (NGC 2244 and surroundings) – presented in Fig. 4). For this image I collected more, but shorter, exposures to battle both the local light pollution and the Alt-Az mount issues (22-60 second exposures were utilized). The collection and processing details were similar to those employed for the earlier Flame-Horsehead nebula photo. I am quite pleased with the capabilities of Adobe Photoshop Lightroom 4. Some people indicate that only the expensive full Photoshop will be suitable for processing, but the capabilities of LR4 ($114 from Amazon these days) are quite impressive for most of my needs. 4.) Post-Stargaze (and equipment repair) successful imaging of Rosette Nebula (NGC 2244) Hopefully next year I won’t be so clumsy and become a short timer while the observing conditions are so glorious. Hans A Heynau

A Stargaze Short Timer’s Report  
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