This might well be the only blog post for the month of July 2013.
Between having to focus on vacations, family, and work, I would rather spend the time used for writing on Ghost Story. I will most likely be doing some photography and hopefully more astrophotography. I may post additional blog entries, but I am not going to try as hard to do so as in a “normal” month. This month is going to be my “lazy” month, at least as far as this blog goes. I most likely will post something around the 24th, I’m just not going to make any promises.
Some of my upcoming vacation time I’d rather get out of, but there’s no way to avoid those particular “obligations” now. The time could, I think, be better spent in other pursuits but unfortunately I was convinced by my better half. 😉 I can’t really blame her as I agreed willingly, it’s just that now as it gets closer to time to honor those commitments, I can see things I’d rather do, like fishing, photography, exploring the back country. I’m just not a party guy.
Last weekend was freaking hot. We went from cool and frequent rain to 100+° F without an adjustment period. Essentially, this past weekend was our bodies’ adjustment period. The forecast doesn’t show anything under 100° F anytime soon.
Still, I did manage to try some astrophotography last weekend and get my Celestron into play. All the recent cold and rain made setting up a little slow due to getting out of practice, but it wasn’t too bad. The alignment went reasonably well and the target came out fairly nice, I think.
It was very difficult, at least this first time in a long time doing this, to focus the telescope correctly via the webcam, a Logitech QuickCam Pro. I didn’t want to focus by eye then have to attach the webcam, remove the webcam and repeat the focus because I bumped it. So, I attempted to focus with the webcam, which induced some delay between adjustment and the view on the computer screen reacting. In hindsight, I should have upped the fps (frames per second) during focusing.
Add to that I was shooting Saturn low on the horizon, about 18° high. In that situation you have the added issue of most of Earth’s air being in the way after a very hot day. With all of Nampa that exists between my driveway and the SW direction where Saturn was, there was still a lot of ground-released heat rising, resulting in turbulence. I would estimate the ambient temperature was still in the upper 80s, low 90s at the time.
For those reasons, I call that picture “fairly nice”. I’m sure with a fixture rather than just a rubber band around the eyepiece and webcam, I’ll be able to do much better with practice and at my favorite dark sky location. Especially with the target higher in the sky.
I think I also need to look for some better webcam software. There may be nothing wrong with the software I have, but the programs I use each seem to have one thing that I really want and none have everything. Typical, eh? So, I need to see if I can find some nice software that allows me a high frames per seconds for focusing purposes, better control over the webcam parameters, and saves to a JPG rather than a BMP. JPG quality always seems better than BMP quality, all else being the same. Of course, I could also just shoot a video and use the stacking software on all those frames instead of a few selective JPEG stills. I’ll be trying that next.
I tried both afocal and direct mount, essentially making the webcam the eyepiece. I wanted to try and take advantage of the additional focusing capability of the webcam proper. It didn’t work as well as I’d hoped, either way, mostly due to issues focusing when not actually looking through the eyepiece but I did learn some things for improving on that. I also managed to try a mockup for attaching the webcam to the eyepiece for afocal shots and will be building that with PVC pipe, one of my favorite building materials. It’ll just slip on over the eyepiece and automatically center the webcam properly. A rubber band will hold the webcam cable to the OTA to hopefully reduce drag on the drive motors that would be induced by just letting the cable hang from the end of the telescope to the laptop. That’ll also help protect the cable from getting accidentally snagged during tracking or slewing to a new target. For the time being, I don’t intend to remove the webcam lens and make a direct eyepiece replacement.
I also hooked up Stellarium and drove the telescope with that. This brought out just how critical it is to get the telescope properly oriented prior to firing up Stellarium to control it. With my largest eyepiece, 22mm, I aligned the telescope with the GoTo controls and the red dot of the finder was dead on when the target was centered in the middle of the eyepiece. Switching to a higher power eyepiece, under Stellarium control the telescope would be aimed high and to the left, not much but enough to put the target on the very edge of the view, or out of it depending on the eyepiece. It was consistent, though, so whatever it was that caused this discrepancy, it was a fixed value. I may need to use a higher power eyepiece during alignment, perhaps, or it could be due to a location discrepancy between the NexStar and Stellarium setups or databases. I’ll have to run some checks to see.
Even so, I did manage to get a look at M5 (a globular cluster), Saturn, M31 (Andromeda Galaxy), and M8 (the Lagoon nebula). Saturn and M5 were the two that were easily visible, Saturn being naturally bright and M5 higher up in the sky. The other two were “there”, but very difficult to see due to light pollution pesent at my driveway along with their location low on the horizon.
It was great to see all this working together as I’d hoped, even if the results were slightly disappointing this time around. I’ll likely play around with the webcam for a while before I mount my Pentax DSLR on the telescope. Then we’ll see what kind of pictures I can get!
Have a safe and sane 4th, everyone!