Thread: any backyard astronomers here?

what i'm looking at is only 700 bucks and has a 10" primary. that seems huge for that kind of cmuf. it's not motorized but has encoders in the mount which you don't have to use so you can do it like they did in the old days by star hopping. i've found the andromeda galaxy by doing that. then again, there is a 10" dobsonian with no bells and whistles almost brand new on craigslist a couple of towns away for really short money.

the biggest problem with my current scope is the finder is a half a binocular screwed to the tube. plus the whole thing is jiggly even after being rebuilt. at one point during it's life the duct tape wedging the spider in place dried out, and the whole thing fell onto the primary, damaging a minimal area. i don't know where the tool is anymore so even if i had the psychic energy i don't know if i could repolish it, or god forbid, have to go back to fine grinding and repolishing.

i guess i've done enough observing to know that i'm not going to get national geographic quality views. I made a 4" dobsonian out of a purchased mirror before i committed to making a mirror and was walking home with it one night after looking at a spectacular view of saturn. i got accosted by a drunk down the street who wanted to know what i had. i set the scope up, let him take a peek, and he came away from the eyepiece saying, "Wow, that's really real."

I used to be in to astronomy years ago. My first scope was a 4.5 inch reflector I built myself when I was around 19. A newtonian reflector will give you the best image. The schmidt types are compromise with small size and an easy viewing angle but you give up resolution in exchange. Of course a dobson is big.

it's all a matter of how serious you are into this stuff. An 8 inch newtonian is the best of all worlds. Good mag and resolution yet still portable. If you go with the schmidt types I wouldn't get less than a 12-14 inch. Of course this stuff starts to get very expensive with all the add ons and computer control and all that and varying quality of eyepieces. Those new units, well not so new really are neat to find just about anything short of a computer tie in. Add a laser to a Sky Scout and you're in business.

I just found as time went on I had to travel more and more to get a decent night sky and then there are the elements and the viewing angle with a newtonian. I still have my 6 inch meade though it basically gathers dust.

Yeah, bad telescope mounts and light pollution have done more to wreck backyard astronomy than anything else. People buy a cheap telescope at a discount store and then the mount is so wobbly that the view constantly bobs around so that they can't get a steady view of anything. Then they decide astronomy is too hard and never try it again. It's amazing how much difference the mount makes. A small telescope can be great if the mount is stable. I agree with thebigspendur that size matters a whole lot when you have to travel. 1) it has to fit in the car and 2) sometimes to find a really good spot you have to hike on foot. I don't think I've ever seen a 10" dob that wasn't a major hassle to hike with. It takes one person to carry the tube and one to carry the base unless you want to make two trips. That matters a lot if it's a mile back to the car. 8" is definitely the best trade off and for some people that is still too heavy to lug around. Or you can try light blocking filters that screw into the eyepieces. Those help some but I think they tend to block too much light at certain wavelengths so you gain in some ways and lose in others. I have a feeling though that if I was getting back into astronomy I'd go with the filters. Walking around with a big telescope just isn't that much fun anymore.

Lori

Originally Posted by Noisykids

what i'm looking at is only 700 bucks and has a 10" primary. that seems huge for that kind of cmuf. it's not motorized but has encoders in the mount which you don't have to use so you can do it like they did in the old days by star hopping. i've found the andromeda galaxy by doing that. then again, there is a 10" dobsonian with no bells and whistles almost brand new on craigslist a couple of towns away for really short money.

the biggest problem with my current scope is the finder is a half a binocular screwed to the tube. plus the whole thing is jiggly even after being rebuilt. at one point during it's life the duct tape wedging the spider in place dried out, and the whole thing fell onto the primary, damaging a minimal area. i don't know where the tool is anymore so even if i had the psychic energy i don't know if i could repolish it, or god forbid, have to go back to fine grinding and repolishing.

i guess i've done enough observing to know that i'm not going to get national geographic quality views. I made a 4" dobsonian out of a purchased mirror before i committed to making a mirror and was walking home with it one night after looking at a spectacular view of saturn. i got accosted by a drunk down the street who wanted to know what i had. i set the scope up, let him take a peek, and he came away from the eyepiece saying, "Wow, that's really real."

Star hopping is the tried and true method. Even with the encoders it's not fool proof so sometimes you have to nudge the tube a bit in the right direction to center the desired object. I had to learn where stars and other objects were back before there were encoders so I have kind of a biased opinion on those. I think it's best to just know where all the major naked eye objects are in relation to each other. Then if you're out somewhere and see someone new at the hobby with a little scope or a pair of binoculars having a hard time you can say, "No, it's over there."

An 8" is a huge improvement over a 4". It has over twice the light gathering capacity. Things start getting exciting with an 8" mirror. A 10" is even better. As you've noticed the other accessories make a difference. I know how frustrating a bad finder scope can be. They don't have to be an actual telescope themselves. They just need to be steady and aligned correctly. A cheap 10" dob that is sturdily made is a great find. Bells and whistles don't help that much but good quality does. Remember that magnification not only increases the view but it also increases the wobbles. Check any scope you can see in person to make sure the wobbles are kept to a minimum.

Lori

Just checked the scope. It is Sky-Watcher Skyliner 200 with a Dobson mount. Probably not the best there is but ok for the kids 1st scope. We've been considering getting an adapter for Canon SLR mount. Any recommendations where to get such with reasonable price?

I've only ordered from Orion but that's in California. I don't know what's available in Europe. Orion might be willing to ship there though.

Lori

I've had both a large 12" Dobsonian and an 8" Schmidt-Cass. The Dob had Intelliscope, and the S-C has Goto. I preferred the Intelliscope, primarily because it was faster just to push the scope around rather than wait for the Goto motor to find its target. And the Goto only goes in one direction, to the right, so if your next target is 5 degrees to the left, it'll make a full 355 degree turn to get there! S-Cs also have a problem with fogging up much earlier in the evening than a Dob will.

The problem with the Dob was that it was huge. I used to have a Jeep Cherokee, and I could barely get the whole getup inside. A 10' is a bit more manageable but still large. It's hard to get a sense of how huge they can be from just pictures in the catalog. The Dob, being a Newtonian, also had a lot of maintenance issues. The mirrors had to be collimated a lot, and the larger the aperture the more sensitive the mirrors were to getting knocked out of place. I assume because they were heavier.

My current 8' Schmidt Cass works well, though. It doesn't have the maintenance issues and is very portable. If I had a stationary viewing area, though, I'd prefer a Dobsonian.