Top photo iphone shot of back of EOS T1i camera display. Kind of fuzzy, but display shows saturn in Liveview mode. The liveview mode will also work with scaling on the EOS utility program that came with the T1i. The screen below shows a preview image on the Mac inside the EOS utility. (I sharped up the second image a little which is a screen shot of the Macintosh.)
This is more from distant recollection now. I've been out there so many times it's more like a blur of memories, of half awake ones.
So I went out to see what I could view. I worked on the mount briefly, just trying to get the controller to follow commands, or rather find the proper commands. They say in the book it's a steep learning curve for beginners. I'm definately in that category when it comes to the Losmandy mount. I couldn't seem to get the goto to work, but it was probably because I was in the wrong menu or following down the wrong path. There are manuals and discussions about the Losmandy mount online, I'm not putting the link here, but can post it later if someone is interested.
So I started observing again. The goto when I select something goes off by about 10 degrees. Now what could cause this? Maybe a wrong model. but also perhaps someone moved the mount physically. This mount doesn't have digital setting circles to read it's position, it stores it's position in a memory chip inside the mount. This chip keeps the "star model" stored inside and that model hopefully remains inside the mount in a permanent setting like the observatory from session to session.
Okay enough technical details. Let's just say the mount is off by about 10 degrees RA when you aim it with goto and a little on the declination axis. What is RA and DEC. On an equitorial system the mount points toward true north, in alignment with the north and south poles. In the northern hemisphere, astronomers will point the telescope mount toward the north pole. RA is Right Ascension and basically relates to how stars appear to ascend from the East and rise up around the north pole area, near Polaris - our current "north star", and then after reaching their peak continue along that path. It's the path the star takes, ascending from the east. Another way I suppose you could think of this would be Right Ascension and the "morning star" as in references to that rising. Or RA, kind of like Ra the sun god ascending from the east and setting in the west. RA - Right Ascension.
On a Gem mount like the one we have in the observatory, the counterweight hangs below the telescope mount. The counterweight is moving when the telescope is moving along the RA axis of the mount. So the counterweight falls and ascends as well in relation to the ground or axis/shaft that the scope is mounted on. Right Ascension is following the movement of one star if you're aimed at it and the Declination axis is set and locked on that star.
Declination is how far up or down you are looking on the axis that is spinning along in parrallel with the earth. In other words, it's the north and south point along the same axis. It's kind of difficult to visualize and I should probably reword this better or show an illustration, buy you can look it up with Google and find out more and I'm sure there's some good illustrations on the net. This is how equatorial mounts work. In the old days, many of these mounts had a motor on the Right Ascension axis or you could add one. The motor would be geared down to rotate in the opposite direction that the earth is rotating and thus it would stay aimed at the star you were pointing at. They even had speed controllers, that you could buy. These speed controllers changed the frequency of the AC current in the motor. They were frequency speed controllers that changed the frequency of the AC sign wave and thus speed up or slow down the Right Ascension motor. But many early mounts didn't have a "Declination" adjustment motor.
There are slight errors in tracking that can occur and you may have to move the mount slightly on it's north and south orientation (Declination). A simple way that I can easily remember that declination is related to the north and the south movements of the mount is a little mind map trick (relational word game I play). I know that the North and The South fought the Civil war. That brought about a temporary DECLINE, in American power, of course because the civil war took resources away and we were weaker at that time. Some might say our strength temporarily declined during the civil war between the north and the south. Decline is a word that of course corresponds to "declination" so I can think about the Civil War between the north and the south and that's a kind of "decline - nation" or declination. See how a simple word game can make things clear. Maybe not, maybe I've been up to much lately and need more sleep.
I took some photos and the session took a familiar turn, which is I said to myself I'll be there for a couple of hours, but once I started looking through the scope, I was having so much fun 4 hours passed.
Saturn was really sharp in great viewing conditions. I had never seen it that sharp or big in my small telescope of course. I hadn't looked at Saturn in a long time through a big telescope. The rings were razor sharp, I could catch perhaps faint glimpses of rings or clouds on Saturn, but they were so faint, perhaps due to faint seeing conditions or my bad eyes, that I couldn't clearly see them, more like a temporary perception almost with averted vision. The moons hung out like jewels near the Planet. I threw in the 10mm eyepiece and 9mm eyepiece in the C-14. The image held up nicely and was bigger. I wanted more power. Would the 6mm show more detail.
I pulled out an old 6mm eyepiece that I own, a University Optics Orthoscopic eyepiece. It probably cost me $40 or $50 over 30 years ago and you can almost get these for the same price today. Saturn was closer, but there were no more details. Still fairly sharp, but details were not improved and if anything it was slightly softer, than in the lower powered eyepieces. Limits in the eyepiece and the seeing conditions apparently would not let me get the best views, but closer views, with the 6mm.
I tried to take some Pedestrian photos with the 6mm eyepiece with my iphone. This is very difficult because the light throw of the cone or EXIT PUPIL from the eyepiece is very small. I had to take my iphone out of it' cover to get the iphone lens closer to the eyepiece. I even tried taking a movie. I'm going to have to review this to be sure. Actually it may have been with the 9mm eyepiece instead of the 6mm. Because the 9mm has a little more light throw. But in any event, you can sometimes get a little glimpse of a planet using a camera phone and carefully "flying" over the small high powered eyepieces. Most often you'll get a slice and part of the cone of light and not a really nice photo.
I tried to get some movies in the iphone of the planet as well. My iphone 3GS has a movie mode and can take 640 by 480 resolution movies. The best planetary imaging by astrophotographers who are amateurs often come from little webcams that cost less than $100. How is that possible? They take a movie clip of the planet. The atmosphere that we are looking through, (sky conditions) changes and varies with ripples and bubbles of hot air constantly changing. It's almost like we are looking through a bunch of invisible soup bubbles of heat in the air, and these bubbles of heat are about 4 inches in size. We are looking through small heat bubbles and other particles of course can be up there as well, ice particles, temperature changes, etc. These cause images to slightly change as the conditions vary at a very fast rate. During poor seeing conditions a planet or even the moon can appear to jump around as if it's dancing in a hot mirage with thermals rising off a hot highway or desert. These images jump around more in poor seeing conditions, but slight variations in quality are happening even in very good conditions. The variations are quick and ever changing. If we take a movie of the planet using a video camera, each frame is getting a very brief picture of the planet in a time slice inside the movie. Movies of course are moving pictures, so we can use a computer program that will take perhaps thousands of these pictures (remember the video camera in the US is recording at 30 FPS) and this means 1800 frames a minute or photos are taken in our movie clip. A computer program can automatically look and detect the sharpest images, probably using edge detection techniques. And it will select the sharpest ones. Perhaps 200 of the sharpest ones out of a 3000 frame set of pictures. You can imagine how long it would take a person to manually look through 3000 images and select the 200 best or sharpest photos. A computer program can do this very quickly and then use a feature called Stacking to merge those 200 sharpest photos and present one image. This image can then be manipulated with some adjustments in a photo editing software package and you'll get the best image from all those produced. Our eyes can't respond and store the best images and stack them in a memory system and then present them to our brain, but the computer can.
We may perceive almost subconsciously a quick amount of quality during varying conditions, and seem to see more detail, but the overall sharpest images are blurred out with the overwhelming number of poor moving fuzzy images. So the eye has a disadvantage over a simple camera and movie software and some additional computer programs.
But if I take some quick photos even with an $800 CCD camera like the EOS t1i, I'll find that simple exposure is often not as sharp as what I will see in the eyepiece. This may be because I'm still inexperienced, but every photo I've taken looks less sharp than what I'm seeing in the telescope. Even with an EOS mounted on the C-14 using mounting hardware. Even a properly mounted EOS camera up to now has not produced images nearly as sharp as I can see with my eye on the eyepiece. The lesson of that night is, you really need to come out and look at Saturn yourself through the eyepiece. The photos I take or post here will not show the quality that you will see through an eyepiece when viewing conditions are good out.
I stayed out until about 3:30AM at the observatory. Part of the problem was I was so cold and tired and slow moving by the end of the night I couldn't quickly get out of there. But for the most part you can blame it on Saturn. I looked at some other objects as well and took some photos. I'll have to review them and double check the time date stamps before making further comments. I will post one of the photos here later under this post. As I post this I don't have time to find and upload a photo.
I have a lot more to post and will post some more updates soon. As the weather gets worse I'll have more time to sleep and then review and post images. Clear skies have slowed down my posting.
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