Years ago, I was interested in the posts on the AAVSO website that dealt with the PEP (Photoelectric Photometry) Group, and I posted a comment about how I'd be interested in joining them someday if I could get the right equipment. I forgot about that post, and then, early in April 2015, I was contacted by AAVSO member Tom Calderwood through email. He'd noticed my post and asked if I was still interested, and wanted to know what type of telescope I had. He also wanted to know if I'd ever acquired a photometer, and mentioned that he and Jim Kay (PEP Section Leader) were trying to stir up more interest to this small group and that another observer would be welcome.
Although I was interested, after some further correspondence with Tom, I found out that what I had at home was inadequate. The 10" LXD55 was the wrong type of telescope (Newtonian type), and it's mount hadn't been able to track the sky for years for whatever reason. The scope had to have a clock drive that worked well.
Since the 10" scope, with all of its problems, was all I had to work with, I dropped the idea of joining the PEP Group soon after that first email, though I corresponded with Tom off and on over the next few months. For example, I saw an ad on the local Craig's List website last summer that showed a Celestron 8" scope for sale, and I thought that it might be a good instrument for photometry. However, Tom wrote back that he was concerned that it wouldn't be stable enough for the weight of an SSP device because it had the one-arm mount design. So, with his advice, I scrapped that idea and kept looking online.
I liked the idea of Photoelectric Photometry for a lot of reasons. First of all, it can be done without ideal dark sky conditions, and I rarely get these in the Indianapolis suburbs! Light pollution isn't much of a hindrance, since the variable stars that are observed are fairly bright (7th magnitude or brighter). Good data can be acquired even with moonlight around. Secondly, if performed carefully, the data can actually be more accurate than what most CCD observers obtain. Also, I have been aware that for the last decade or more, there are a lot of automatic all-sky surveys that image big parts of the sky every few nights. These surveys, however, don't cover the stars that PEP observers look at, so this seems to make the PEP data even more valuable. And, finally, there's an even more personal reason that I'm interested in starting with this branch of variable star work. I've been nearsighted since early childhood, but almost four years ago, I was also diagnosed with astigmatism. My eyes seem to have gotten a lot worse in the last five years, and I'm not sure if I really trust the visual estimates that I've been making for the AAVSO. (Of course, part of the problem may have also been that the optics on my 10" telescope have been exposed enough to need recoating.) PEP work could allow me to make very accurate brightness estimates whether my eyes get worse or not.
So, a couple of weekends ago, I decided to at least check out the eBay website to see if any Optec SSP-3 Photometers were being auctioned. Interestingly, I saw three of them for sale. One was selling for over $400 and one for over $300, but one was being offered for just $85. When I'd gone to the Optec website in the past to price brand-new SSP-3 instruments, I hadn't seen one for less than $1000! I couldn't believe that they were so much cheaper on eBay, even though these were all pre-owned and used ones. I consulted Tom again by email to see if he thought there might be an issue with such a cheap SSP-3. He wrote back that he'd bought several of them through eBay and that he hadn't had any really bad experiences. He also advised me not to bid more than $200 on it, telling me that he knew he could find me one for about that price elsewhere.
I looked the SSP-3 over after it arrived. Tom had advised me to check out the filters that came with it (two of them, in this case), to see if they looked cloudy, They didn't seem to be. He also wrote that maybe I should try using it with my 10" scope on a target like Polaris, since that star wouldn't drift much even without a the scope's tracking system working. I thought about doing that, but there weren't many clear nights for the next week and I never got around to trying.
I looked over a lot of telescopes on eBay after making the purchase of the photometer, seeing if there was anything that I could afford. I was looking at Meade and Celestron Cassegrain types that were 8" or larger and that weren't mounted on the one arm, but mounted with fork type mounts or german type equatorial mounts. Even on eBay, anything larger than 8" was out of my price range (I didn't want to charge more than $1000 on my credit card). I went back and forth a lot in my mind, telling myself to go ahead and get a new scope (since I hadn't bought one since November, 2002), and then talking myself out of it. A couple of ads, however, stuck in my mind. And then, this weekend, I "took the plunge" again.
The seller of this telescope is currently on vacation, but he emailed me late on Saturday afternoon to let me know that he could ship it on Tuesday (November 1), so it may be here by next weekend. To be honest, I'm excited about this, even though I'm feeling a bit guilty about spending the money.
It seems like big changes have always come to my hobby in November, and that month is almost upon us again!
36 years ago, in November 1980, I first started to learn the constellations and use a pair of 7x35 binoculars to explore the night sky. Then, by Christmas 1980, I had my first telescope ever, a 50mm refractor (which still sits in my shed in the back yard attached to my second telescope).
34 years ago, in November 1982, I had my 6" f/10 home-built reflector all put together, and I first started using it for lunar, planetary, and then variable star work. This was my telescope that I used for the AAVSO when I officially joined it in June, 1984, and kept using on and off for the next 20 years; reporting about 400 variable star estimates with it during that time.
Then, 14 years ago, in November 2002, I had my 10" f/4 telescope. I used it to report about 1,600 more variable star estimates to the AAVSO, along with using it to take lunar photographs and make sketches of the Moon, make some planetary observations, see some comets, and even track down some high-altitude rocket bodies orbiting the Earth. That 10" scope had a good run, and I still haven't given up on it. I think that with some further work, it can be restored back to usefulness.
Now, in November 2016, I'm about to get my fourth telescope ever. I think it will be very useful for photometry and many other things. I'll see how it goes, and I'll document it on these pages.
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