Post by erikruud on Aug 1, 2007 10:53:43 GMT -6
Hello,
I am married and have two children. My daughter is 10 and my son is 2 and a half.
As long as I can remember I have always wanted a telescope, but I never managed to acquire one. As a kid it was due to a lack of funds. As an adult it usually came down to a matter of priorities.
My interest was revived last year I took my kid’s over to the “American Science & Surplus” store in Geneva for a star gazing night. We had a good time looking at the moon, Venus and Jupiter through the various telescopes that were set up. Even my wife showed some interest, but decent beginner scopes were still more than she wanted to spend. As a family we are already involved in karate, ballet/tap, horse riding, swim lessons, etc.
At the beginning of July, I finally reached my 10 year anniversary at work. I was not surprised to learn that we had changed vendors again for our service awards. It seems to happen every 3 years or so. I was surprised to learn that the new program actually included useful things. In addition to the usual clocks, watches or crystal items, there were things like a DVD player, a 14V cordless drill, an ice cream maker, etc. I went through the list and found that there two things I didn’t already have and that I might actually use. One was a meat smoker and the other was a Tasco 70mmX800mm telescope.
I decided to get the telescope. I knew it wasn’t a really good scope, but it was free and it was better than no scope. At a minimum, I knew we should be able to look at the moon.
I filled out the forms on the website and in less than a week I had my first telescope. According to the website it was supposed to be a Tasco 70mmX800mm on a single fork Alt-Az mount, with two eyepieces, a diagonal, a red dot finder, and SkyWatch software CD. The box that arrived actually contained a Bushnell 700mmX800MM scope, with three eyepieces (12.5,8 & 4 mm’s), a diagonal, an erecting eyepiece, a different Alt-Az mount with lighted degree scales, a red dot finder, a compass, and a hand held talking SkyTour device. As far as I can tell the Tasco and Busnell are the same scope. The optical tube assembly looks the same. It is just the mount and accessories that are different. The mount has a slow motion adjustment for the azimuth but not for altitude. The altitude does have a thumbscrew to lock it in place.
I had to wait three days for the clouds to move out before I got my first chance to actually use it, but on Friday night the sky was clear and the moon was above the trees to the south of my house. I was able to get a good view of the moon with the 12.5 mm eyepiece. I was also able to get good views with the 8 and 4 mm eyepieces. After looking at the moon for a while I decided to see if there were any planets in view. I fired up the SkyTour and it informed me that Jupiter was at 205 degrees azimuth and 22 degrees altitude. I moved the scope to those settings and I could see that it was pointing at a very bright object, so that part seemed to be working. Then I tried looking through the scope with 12.5mm eyepiece and there was nothing in view. After a couple minutes of searching I was able to get Jupiter in the center of the view. I was surprised that I could actually see 4 of the moons as pinpricks. Part of the problem was a certain amount of altitude wobble in the mount. Part of it was my inexperience. I tried to switch to 8mm eyepiece, but I wasn’t able to get Jupiter in view that way and I gave up because the mosquitoes were starting to get bad and the moon had gone behind some trees.
On Sunday my daughter and I went over to a nearby park were there were fewer trees to worry about. Again we were able to get good views of the moon with all three eyepieces. An again I was able to use the SkyTour to locate Jupiter and get a good view through the 12.5mm. I did have to scan a bit first because the altitude seemed to be a bit off. I tried switching the 8mm and this time was able to get Jupiter in focus. I then tried the 4mm and after a few minutes I was able to get Jupiter in focus again and now we could see one of the bands as a faint grey line. It was pretty cool, but I was getting frustrated with the wobbly mount. We then tried to see what other planets we could see and discovered an annoying “feature” of the SkyTour, It does not exclude planets that are not visible. It happily tells you that mars is at x degrees azimuth and x degrees below the horizon. So then we decided to see what constellations were visible. The first two that the SkyTour pointed us at were Virgo and Bootes. It was too hazy to see most of the stars in them, but my daughter wanted to see what Arcturus would look like through the scope, but the wobbly mount was too frustrating and we went home.
At this point, I still hadn’t tried to calibrate the red dot finder.
I did a bunch of research on the web and found that there are a number of things that I can do to improve the performance of this scope.
Especially these sites:
hometown.aol.com/davetrott/page15.htm
www.homebuiltastronomy.com/twotube/Construction4.html
Yesterday I went over to Ace hardware and got a bull’s eye level and an Angle Locator. After I got home, I set up the scope on the driveway and started trying to calibrate the red dot finder. I was able to get it calibrated, but I did find that it has a bit of slop in it as well. Once it was calibrated, I was able to use it to point at different objects down the street and they were more or less centered in the scope. I attached the angle finder to the scope tube with some zip ties. That way I don’t have to worry as much about getting the tripod level which can be difficult without any type screw adjusters on the legs. According to the angle finder, the degree scale for the altitude axis is off by 3.5 degrees. That explains why nothing was ever correctly lined up when I used the SkyTour settings. I was also able to measure the wobble in the mount at +/- .5 degrees using the angle finder.
I took the mount apart and found that there is a rubber washer between lock nut and the slow motion azimuth gear. No matter how much I tightened the lock nut, the rubber washer allowed the mount to wobble. I removed the rubber washer entirely, and I was able to tighten the nut enough to remove the wobble while still allowing the azimuth to rotate smoothly. I think I am going to locate a nylon washer to use instead to reduce some of the friction. Now the only wobble is due to the tripod itself, and I have a few ideas for that as well. Hopefully I’ll get a chance to test it out tonight.
Another thing I think I need to do is find a way to orient the scope so that the zero degrees of azimuth is facing true north. Polaris is hard to see from my house due to the trees. The compass that came with it does not have any magnetic declination adjustment, and there is no way to be sure that you really have the axis aligned correctly. You just have to eyeball it.
Eventually I would like to try building a better tripod and mount. I have the wood working skills and tools, so it shouldn’t be too hard.
I also have a copy of Starry Night- Night Sky Explorer that we picked up sometime last year. I installed it on my laptop so that I can use it locate visible objects. The SkyTour thing is kind of neat, but it is also annoying because you have to step through it’s menus until you find the object you want. You can’t just look up Mars.
If I can get this telescope to work reasonably well, we will probably use it enough to justify getting a better scope.
Thanks for listening,
Erik Ruud
41.9N 88.3W
I am married and have two children. My daughter is 10 and my son is 2 and a half.
As long as I can remember I have always wanted a telescope, but I never managed to acquire one. As a kid it was due to a lack of funds. As an adult it usually came down to a matter of priorities.
My interest was revived last year I took my kid’s over to the “American Science & Surplus” store in Geneva for a star gazing night. We had a good time looking at the moon, Venus and Jupiter through the various telescopes that were set up. Even my wife showed some interest, but decent beginner scopes were still more than she wanted to spend. As a family we are already involved in karate, ballet/tap, horse riding, swim lessons, etc.
At the beginning of July, I finally reached my 10 year anniversary at work. I was not surprised to learn that we had changed vendors again for our service awards. It seems to happen every 3 years or so. I was surprised to learn that the new program actually included useful things. In addition to the usual clocks, watches or crystal items, there were things like a DVD player, a 14V cordless drill, an ice cream maker, etc. I went through the list and found that there two things I didn’t already have and that I might actually use. One was a meat smoker and the other was a Tasco 70mmX800mm telescope.
I decided to get the telescope. I knew it wasn’t a really good scope, but it was free and it was better than no scope. At a minimum, I knew we should be able to look at the moon.
I filled out the forms on the website and in less than a week I had my first telescope. According to the website it was supposed to be a Tasco 70mmX800mm on a single fork Alt-Az mount, with two eyepieces, a diagonal, a red dot finder, and SkyWatch software CD. The box that arrived actually contained a Bushnell 700mmX800MM scope, with three eyepieces (12.5,8 & 4 mm’s), a diagonal, an erecting eyepiece, a different Alt-Az mount with lighted degree scales, a red dot finder, a compass, and a hand held talking SkyTour device. As far as I can tell the Tasco and Busnell are the same scope. The optical tube assembly looks the same. It is just the mount and accessories that are different. The mount has a slow motion adjustment for the azimuth but not for altitude. The altitude does have a thumbscrew to lock it in place.
I had to wait three days for the clouds to move out before I got my first chance to actually use it, but on Friday night the sky was clear and the moon was above the trees to the south of my house. I was able to get a good view of the moon with the 12.5 mm eyepiece. I was also able to get good views with the 8 and 4 mm eyepieces. After looking at the moon for a while I decided to see if there were any planets in view. I fired up the SkyTour and it informed me that Jupiter was at 205 degrees azimuth and 22 degrees altitude. I moved the scope to those settings and I could see that it was pointing at a very bright object, so that part seemed to be working. Then I tried looking through the scope with 12.5mm eyepiece and there was nothing in view. After a couple minutes of searching I was able to get Jupiter in the center of the view. I was surprised that I could actually see 4 of the moons as pinpricks. Part of the problem was a certain amount of altitude wobble in the mount. Part of it was my inexperience. I tried to switch to 8mm eyepiece, but I wasn’t able to get Jupiter in view that way and I gave up because the mosquitoes were starting to get bad and the moon had gone behind some trees.
On Sunday my daughter and I went over to a nearby park were there were fewer trees to worry about. Again we were able to get good views of the moon with all three eyepieces. An again I was able to use the SkyTour to locate Jupiter and get a good view through the 12.5mm. I did have to scan a bit first because the altitude seemed to be a bit off. I tried switching the 8mm and this time was able to get Jupiter in focus. I then tried the 4mm and after a few minutes I was able to get Jupiter in focus again and now we could see one of the bands as a faint grey line. It was pretty cool, but I was getting frustrated with the wobbly mount. We then tried to see what other planets we could see and discovered an annoying “feature” of the SkyTour, It does not exclude planets that are not visible. It happily tells you that mars is at x degrees azimuth and x degrees below the horizon. So then we decided to see what constellations were visible. The first two that the SkyTour pointed us at were Virgo and Bootes. It was too hazy to see most of the stars in them, but my daughter wanted to see what Arcturus would look like through the scope, but the wobbly mount was too frustrating and we went home.
At this point, I still hadn’t tried to calibrate the red dot finder.
I did a bunch of research on the web and found that there are a number of things that I can do to improve the performance of this scope.
Especially these sites:
hometown.aol.com/davetrott/page15.htm
www.homebuiltastronomy.com/twotube/Construction4.html
Yesterday I went over to Ace hardware and got a bull’s eye level and an Angle Locator. After I got home, I set up the scope on the driveway and started trying to calibrate the red dot finder. I was able to get it calibrated, but I did find that it has a bit of slop in it as well. Once it was calibrated, I was able to use it to point at different objects down the street and they were more or less centered in the scope. I attached the angle finder to the scope tube with some zip ties. That way I don’t have to worry as much about getting the tripod level which can be difficult without any type screw adjusters on the legs. According to the angle finder, the degree scale for the altitude axis is off by 3.5 degrees. That explains why nothing was ever correctly lined up when I used the SkyTour settings. I was also able to measure the wobble in the mount at +/- .5 degrees using the angle finder.
I took the mount apart and found that there is a rubber washer between lock nut and the slow motion azimuth gear. No matter how much I tightened the lock nut, the rubber washer allowed the mount to wobble. I removed the rubber washer entirely, and I was able to tighten the nut enough to remove the wobble while still allowing the azimuth to rotate smoothly. I think I am going to locate a nylon washer to use instead to reduce some of the friction. Now the only wobble is due to the tripod itself, and I have a few ideas for that as well. Hopefully I’ll get a chance to test it out tonight.
Another thing I think I need to do is find a way to orient the scope so that the zero degrees of azimuth is facing true north. Polaris is hard to see from my house due to the trees. The compass that came with it does not have any magnetic declination adjustment, and there is no way to be sure that you really have the axis aligned correctly. You just have to eyeball it.
Eventually I would like to try building a better tripod and mount. I have the wood working skills and tools, so it shouldn’t be too hard.
I also have a copy of Starry Night- Night Sky Explorer that we picked up sometime last year. I installed it on my laptop so that I can use it locate visible objects. The SkyTour thing is kind of neat, but it is also annoying because you have to step through it’s menus until you find the object you want. You can’t just look up Mars.
If I can get this telescope to work reasonably well, we will probably use it enough to justify getting a better scope.
Thanks for listening,
Erik Ruud
41.9N 88.3W
