(A bit of re-editing happened to this post, I'll add photos in another post later tonight if possible.)
Last night I didn't get to sleep until around 2am. I thought I set my alarm and perhaps I did for 4am. If it rang I didn't recall hearing it and turning it off. There's a chance I didn't even set it as I woke up around 5:15am and couldn't get out of the house until 5:25am
Got up late to view the comet. I woke up around 5:14am and didn't get out of the house until 5:25am.
Took my Canon EOS, a laptop and my eyepieces. When I arrived at HJRO I left the eyepieces in the car.
It was bitter cold out, around 23 degrees.
The sky looked good, but I didn't have time to take wide field images. I simply rushed to open up the observatory door, in hopes of setting up and taking as many photos as I could. I had probably less than 25 minutes to open up, setup and take photos before the clock would strike 6am, the effective witching hour for taking photos before the sky grew to bright. I decided to only attempt to take photos with the C14, not the Meade. I didn't have time to setup the Canon EOS on both telescopes, focus and take photos. I also knew that I had a slim chance of getting the Auto-Guider focused and working in such a short time.
The first minute or two, I visually viewed the comet through the c14 with the same 40mm eyepiece I used 24 hours earlier. Comet ISON looked brighter than it did the day before. It's starring to look better now.
(Unfortunately the comet is moving so fast, good close up photos from HJRO with the C14 might only be possible for a couple more mornings (weather permitting). The Meade might reach it better. If we lived in a perfect world I'd have a large easy to setup telescope for photography and the weather would be much warmer, giving me time to setup in the morning near a nice low horizon. With the weather being so cold out lately it's unlikely that I'd setup to to photography with a telescope and tracking in this cold. It might take an hour or two to get a really nice setup. One could ideally use a low focal length rich field setup for the comet as well as it gets closer to the horizon and the tail becomes longer. Having something like a "hyperstar setup" at a nice dark sky site, perhaps something like an over the water view would be nice, something like the dark sky site at the tip of the thumb of Michigan would be awesome for the comet if it provided a nice low horizon dark sky location. )
Took a few stills, with the canon EOS on the c14 before I had the Toshiba PC laptop hooked up to control the camera via Backyard EOS. I like and highly recommend using a laptop or some computer for your photography of a comet, the larger immediate display of the images you take helps you locate the comet in the field, and insure you have a better focus.
Before I setup the Laptop, I tried to focus on the comet using a focusing mask. My mistake due to the rush and lack of time was trying to use the focusing mask with only the small Canon EOS t1i display, reviewing and using the small display didn't work well for me. Perhaps due to the small display, perhaps because I forgot to put on reading glasses. Visually the image at low power of a nearby bright star jumped around with the seeing with the mask on. Rendering a quick use of the mask, useless. I was better off aiming and focusing as best I could due to the time limitations. Using the laptop would be a better way to do this.
Also I want to point out that using my laptop to capture images while focusing is better with one person in HJRO than using the computer in the observatory. We have a large monitor and the computer display of images and controls are setup for a separate operator. You often have to move to the telescope from the position you're in in the observatory to focus the telescope when getting the telescope in focus. A live view perhaps to the other monitor facing the telescope would work, but we often run the configuration with the Windows and Macintosh sides of the Mac Mini going to separate monitors. We haven't optimized the setup in a quick way yet to do solo astrophotography and it's a challenge. I'm better off using my Toshiba laptop for solo imaging runs at HJRO. The USB wire I use for the laptop also works better most of the time, because I can use the large observing chair as a stand and have the laptop up close near the eyepiece and camera. It allows me to stand and setup the telescope focus while observing the results instantly using the laptop.
- I should have dressed warmer.
This morning although I dressed up, the added colder air and rush likely made me much colder. I left the observatory shivering by the end of the session. I didn't use the IR heater at all during the entire imaging and setup, this made the comfort level almost unbearable. I should have worn winter snowmobile boots and a snowmobile pant setup as well to have more comfort. perhaps another layer of clothing and ear muffs as well.
- 5:40am
I took a few photos while trying to get the other stuff setup, the auto guider. Had to setup the auto guider in between exposures taken of the comet.
Had to refocus the Meade for the auto guider and was rushing. Had to go back to a nearby bright star to focus the auto guider.
The auto guider is not recognized by the computer in HJRO, at least it didn't work this morning. Phd guiding software did not see the Orion camera on the Macintosh or PC side.
I quickly tested and discovered PHD guiding software ran on my laptop. But the guiding didn't work very well, for stars inside the field of view near the comet, it could be due to the poor focus I did as I was rushing with phd. I ran 2 minute intervals on some of the star tests to do autoguiding and that ate up at least ten minutes of my imaging time, which made it impossible to get good auto-guiding adjustments and the long exposures I was hoping to get. You really should be at the observatory an hour before imaging is going to happen to setup. Ideally I'd be there at 3:30 and start imaging tests around 4:30 or so for example with the comet if it was first visible around 4:30am. The comet is not visible in the C14 until 5am however so a 4am arrival would have been better. I retrospect I probably should have bundled up more and just went to HJRO and tried to image all night. Perhaps warming up in my car during imaging sessions and test, the results would have been far better.
DIGRESSION EQUIPMENT THOUGHTS: Not that this log is meant to be a gripe fest. but for low targets, we have better viewing using the Meade Piggybacked on the back of HJRO. A more ideal setup for comets would have two cameras piggybacked on the C14, some other telescope that was wide field on the telescope as well, perhaps removing the Lunt Solar telescope for a wide field telescope for auto-guiding. Having a large telescope for auto-guiding would also be idea. Really you'd want a better setup all around, HJRO is far from ideal for imaging comets. To image comets you need a nice dark site, which we don't have. You want a really low horizon, which we don't have due to city obstructions, and you'd want a portable rig ideally that has two telescopes a larger rich field perhaps for the auto-guiding. For high up hard to see deep sky images of comets the observatory would likely do better with our auto-guiding setup. To get faint stars to work with the auto-guider you need to let PHD do the mount calibration for backlash, which can take ten minutes out of your imaging run. So overall we are better setup for fainter comets far above the horizon. What is the big advantage to HJRO vs. a portable rig. There is practically no setup time, as the telescope and mount are there and setup already. There is no hour or longer setup of the mount and telescope. There is less wind because the walls protect the observer. We have a wooden floor with carpet on it, which is much warmer than a observing position outside. For outside observing, unless you were using a large rich field telescope, a wide exposure is probably a much better setup. In this cold weather I don't know if many FAAC astronomers will brave the early morning hours to setup and view the comet visually from any location. (A part of me wishes I had a Faststar hyperstar setup and a trip to a dark sky site to get photos of this comet. But most of those kinds of "cheap rigs" cost nearly $5000. (outside my immediate telescope budget.) The next best way to get a nice comet photo from a remote location is with a DSLR with a lens on a fixed mount. It's relatively cheap. One could use a small tracking mount with the DSLR on it as well, or use piggyback photography with a DSLR on a small telescope which tracked the comet.
THE AUTO GUIDING ATTEMPT
I took one long exposure while phd guided the mount, but phd started throwing errors so I cut it short to 156 seconds, aborting the exposure.
THE SYNC ON THE COMET MISTAKE
Before going to refocus I decided to do a sync on the comet as I liked my framing of it. But the comet is moving and you should not sync to a moving object. By the time I got back from the focus of the Orion guider the comet had moved and my 156 second exposure missed.the comet and showed only half of the comet on the edge of the frame and the tail.
Re-centering the object for a better photographic attempt, I took six 60 second 3200 iso exposures. With phd guiding not working well, I could not get a long exposure. I took six dark frames for stacking and image processing at the end of the session. These were registered as 11 degree C sensor dark frames, and the exposed frames during the run were at 14 degrees C, not perfect, but close enough to perhaps help in the post processing and tweaking of the images.
By the end of the session the chill was starting to really set in. I left HJRO around 7am to go home. Outside HJRO the lights of the middle school had been turned on by morning staff. I don't know if those lights affected the comet photos, it's more likely that the rising sun (sky glow) affected the images.
SUMMARY
It will be challenging to get good images from the massive amount of sky
glow that exists in those photos. I may only have one or two images
that are usable from this mornings session.
It was a real whirlwind of activity today for me at HJRO. I would not say the trip to HJRO was worth it, to see the comet, Monday morning, but Tuesday morning the trip was worth it because the comet is much brighter.
If your able to get the right setup a small telescope and binoculars and wake up early in the morning, viewing the comet visually now would be as rewarding as the nice views we had of Panstarrs. As the comet gets closer there's a chance for unusual outbursts, so that makes viewing this "sun grazing" comet an exciting opportunity. With the Michigan weather I almost felt I could feel cold CO2 particles and ice flying off the comet on my face, but that was just the Michigan weather.
Near the end of the session, I looked at the comet visually through the C14, 6:12am. The sky glow overwhelmed most of the tail by that time, making the comet appear like a fuzzy star, with most of its tail missing. Observing after 6am would be disappointing, you need to be out there at 5am to observe this during the next few days.
I didn't get to sleep until 8am. I'll look, process, and hopefully post some of this morning's comet images in the next post, or edit and add images to this long rambling post.
- Posted using BlogPress from my iPad
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