STARGAZING SESSION IN CALIRAYA , LAGUNA
April 9-10, 2005
by Raymund Sarmiento
Jett, Mac, and I made our rendezvous point at Shell Alabang at around 2 pm. James gave us instructions to wait there until they arrive. At that time he was still waiting for the other guys joining the Caliraya stargazing party to arrive at Shell Magallanes before joining us at Alabang. While waiting for James' group, the three of us had a nice chitchat and obviously the topic of the discussion was about the astronomy, our personal accounts on what is on the list of our "next-steps" plan on our current astro equipment, and our past experiences with our previous equipment, and star party engagements. Odd, there you see three guys talking and not single word on what guys usually talk about ; girls. Well at that point I can easily conclude that astronomy is better than sex. :)
It was around 3 pm when we finally heard a crackle on Jetts two-way radio indicating James group has arrived. After a quick chat with James and Jun Lao, we finally started our journey to Caliraya via SouthLuzon expressway in a 6 car convoy. It was past 6 pm when we arrived at the Calirayas Hilltop Resort. First thing we did was to check the skies. It was a bit hazy at that time and the transparency is somewhat on the negative side. Anyway, it was too early at that point to be disappointed because Ive had a couple of experiences with the skies in Antipolo where I stay which usually has a bit of haze at late afternoons and usually clears up at around 7 to 8 pm. Well true enough, the Caliraya skies started to clear up at around 7 pm.
After checking the condition of the sky we took time to walk around and to check the place specially the observing site, had a quick dinner at a nearby canteen, and waste no time in setting up the equipment. It was past 8 pm when we started to move our vehicles at the observing site which is right on top of a bridge. Good thing we are allowed to park at the observing site because I really dont want to drag 120 lbs of equipment from the trunk of the car to the observing spot. This is were the fun starts, you see everybody else around you doing their own well practiced way in setting up their equipment. I even heard someone shouting because of a missing lock nut or something. Anyway, the entire group proceeded with the equipment setup and it went on smoothly except for some who had couple of mishaps with an animal dung scattered all over the place. I was not lucky also because I accidentally placed one leg of my tripod on some mammals dropping. I had to move the tripod to a spot with the least contaminants. The sad part is these land mines are not easily seen on red light :-D. Anyway, i guess they do work well as vibration dampening material for your tripod legs :-D.
My ORION Atlas EQ mount was delivered to me only a couple of weeks ago and at that time I only had a few practice sessions on the art of polar aligning at my place. Lucky for me, I have a good view of Polaris at my home thus I can do the usual aligning /observing stuff there. I had to take note of each step, the problems I encounter in aligning it, and things should I do to avoid it. Aligning the mount at Caliraya was never a problem at this point. Aligning it with my current setup is a two-step process whenever the mount is on top of a soft ground. I learned this during my practice sessions at home. First I had to make an initial bubble level of the mount and do some rough alignment just to place Polaris within the field of view of the mounts polar scope. At that point, I made some quick adjustments on the latitude bolts and azimuth nuts to bring polaris near the center of the reticle. This is done without the tube and the counterweights. Here is the tricky part, the 10 hardin optical scope plus the tube rings weight about 37-38 lbs plus 37lbs of counter weights. That is almost 80lbs pound difference after the first alignment. Placing them on top of the equatorial head usually results to a significant sink on the soft ground which causes some drift on the alignment. I had to wait for at least for 5 minutes for the ground sink to settle down. Once settled, this where I start the second part of the alignment process. At this point with all that weight on the mount, it is very difficult to make some adjustments on the L-bolts and Az bolts without putting some strain on them. This is the reason why I need to bring polaris near the spot. At least I only have to make a few turns on these bolts just to bring Polaris at the right spot on the reticle with the least strain.
Casual Observation and Tracking Check
At this point I decided to do some observation first before proceeding to planetary imaging. First on the list were the two easy to spot planets; Jupiter and Saturn. Jupiter was some degrees at the zenith when I started observing. I started with Jupiter using the Meade eyepieces and 2x Barlow Jun Lao bought from the US. With the help of a green laser pointer mounted on the scope, placing the planet within the field of view the eyepiece was easy. The two cloud bands are very distinct especially with the 2x Barlow and the MEADE 18 mm eyepiece. The GRS was not visible at that time. I was hoping it would be because this is the only time I would love to see it on a Caliraya dark sky. From there, I started to check on the mounts tracking so far no problems were encountered. The MEADE eyepieces Jun Lao gave us also come with a 5mm plossl. I tried using this with the 2x Barlow on Jupiter just to check the tracking. Focusing is somewhat difficult although there is enough light intensity to bring out the planet details. No drift in tracking was visible (although there might be some probably if I use a camera in long exposure mode mounted on the focuser and leave the setup running for sometime).
Next stop was Saturn. Using the laser pointer mounted on the scope, I aligned the tube in the general direction of the planet. The laser pointer was a big help because I dont have to rely on the viewfinder to bring the planet within the field of view of the eyepiece. Jupiters rings and the Cassini division is resolvable on a 9 mm and the 2x Barlow. The planets shadow on the rings is also visible.
The tube is originally designed to sit on a Dobsonian platform. Putting it on a Equatorial tripod is an entirely different thing. For starters, the focuser/eyepiece is located at the tube opening. Because of the length of the tube and the height of the tripod, I rarely use the scope's viewfinder because of its location. I had to bring along a portable ladder just to reach the eyepiece and the viewfinder. I used to work with alt-az mounts and transferring to an equatorial system is quite an experience.
After the planets, I decided to do some casual observation on DSOs. Jun Lao was kind enough to help us pinpoint the general direction of the some of the Globular Clusters. First stop was the Omega Centauri Global Cluster. Here is the tricky part; this was actually my first time to point the tube close to the southern part of the sky. I usually dont do that at home because of the houses blocking the area. Being a first timer on Equatorial Mounts, I had a difficult time pointing the scope to the general direction of the cluster. I cant use the laser anymore because the others are already into imaging. In the process of rotating the mount at the Right Ascension axis, I accidentally stretched the 12-volt power cord and pulled it into two pieces :(. Anyway one quick fix with a cutter and James electrical tape, I was back in business. With some experimentation with RA/DEC position of the mount, I was able to point the tube to the Omega Centauri Global Cluster.
With a 18mm eyepiece, the view was spectacular. Jun tried to check it also on my scope and I heard him comment that it looks 3D. Dante, Mac, and John also took some time to check the cluster on my scope. Mac noticed some thermal distortions on the entire view. Jun explained that it could be the thermal variations inside the tube or it could be the distortion on the atmosphere itself. Nevertheless, it was one heck of view considering the sheer number of stars grouped in one place. Next stop was M4. Aligning the scope to M4 is quite difficult. At that point the viewfinder was dewed already and its very hard to use the laser pointer as guide especially with the naked eye. This time I asked Dante to help me find it. With the aid of a binocular, we were able to locate M4. To be able for us place M4 on the field of view of the scope, I had to look at M4 with the binocular, while Dante is at the switch of the laser pointer. With the binocular on my right hand and the mounts controller on my left hand, and while the laser is activated, we were able to make some fine adjustments on the laser beam towards M4. You can actually see the beam sweep towards M4 on the binocs while doing the RA/DEC adjustments on the mounts hand controller slewing the scope at 8x. At that point M4 was already in the field of view. After some centering adjustments using the hand controller, we proceeded with the observation of M4 using the same 18 mm eyepiece. M4s details were resolved but it is not as spectacular as the Omega Centauri cluster. I was also hoping i could see the Genesis planet tucked within M4 :) LOL.
After the DSOs, Ive decided to proceed with the imaging of the two visible planets; Jupiter and Saturn. I was supposed to try Pluto too with some help from Allen with regards to its location, but the viewfinder is already soaking wet and its not easy to locate it considering its distance and size. Star hopping is not an option at this point. I decided try Saturn first and then Jupiter. Using my laptop, a Logitech 4000 CCD webcam fabricated with a 1.25" Mogg Adapter, and a 2x barlow, I was able to capture 400 frames of the two planets and stacked them together using K3CCD. I was hoping that I could resolve the Cassini division on Saturn using the webcam but I was not successful because I was not able to focus it well. At that point I cant make another Saturn capture because planet is already behind the trees. The image of Jupiter did came out well and showed some intricate cloud patterns on the Planet.
It was already 3 am when I got the images of Jupiter and that is the time I decided to call it the night. The viewfinder is heavily dewed including the telescope tube but instead of sleeping, I decided to check on the others see how are they doing. That is when I noticed Macs film camera piggybacked on Jets scope trying the do some long exposure shots of the Milky Way. I asked Mac to use my mount instead since I cannot use anymore the scope because of the dew.
At this point, I remove the tube and the counterweights and mounted Macs film camera on top of the dovetail plate. Mac took shots of the Milky Way with the Atlas Mount at different angles. Since there is no ball joint provision for the Camera, both RA/DEC has to be rotated to get the proper angle for the camera. To do this, Mac has to kneel down and look at the viewfinder while I hold the RA/DEC lock levers. Once Mac sees the correct view, that is the time I lock those levers.
Mac tried to take shots of the Milky Way as many as he can until the sun rises. Per shot took him 20 minutes to complete.
The Sun was already up when the group decided to have the usual group picture. Imagine not a single shuteye and the people can still smile. I really cant wait to see those pictures.
The Caliraya trip was one experience I will never forget. I already listed down the problem I encountered and hope that I will be able to address them in the next stargazing session especially on getting rid of the dew on the sensitive optics.
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