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Superman 12-18-2021 05:55 AM

Steve/masraum sent me a PM and generously offered to help me out. Pelicanheads have made me feel proud for twenty years now, and this is the latest instance. Thank you, Steve.

I think I am using my telescope wrongly, and I wonder if I am focusing on the wrong plane. Flatbutt says stars jumped out of nebula. Eric says my magnification should be around 66/1. Pazuzu says color filters can help. Here's the deal: Color filters will not help me because the image would need to be several times larger in order for me to see anything larger than a spec. If I focus just right on Jupiter, I can see it has moons, but Jupiter itself is still WAY too small for any hope of seeing color details.

I'm going to return to my original question. Because of some of the comments I see here, I still wonder if I am using this telescope wrongly. The slidey thingie into which the eyepiece is inserted is adjusted so that several inches of the slidey thingie are protruding from the fat part of the telescope.

I was given this telescope about 3 months ago and part of my problem is meteorological. The Pacific Northwest is a wet, cloudy place. This time of year there are several nights per month in which we could not even detect the presence of a full moon, so thick is the cloud cover. No more than a handful of nights per month present any opportunity to see anything. Right now, the National Weather Service says it will rain constantly until at least next weekend.

I do have a nice neighbor with a telescope I have not seen. Perhaps he can coach me. I think I am focusing this telescope wrongly.

flatbutt 12-18-2021 06:21 AM

Quote:

Originally Posted by Superman (Post 11550444)
Steve/masraum sent me a PM and generously offered to help me out. Pelicanheads have made me feel proud for twenty years now, and this is the latest instance. Thank you, Steve.

I think I am using my telescope wrongly, and I wonder if I am focusing on the wrong plane. Flatbutt says stars jumped out of nebula. Eric says my magnification should be around 66/1. Pazuzu says color filters can help. Here's the deal: Color filters will not help me because the image would need to be several times larger in order for me to see anything larger than a spec. If I focus just right on Jupiter, I can see it has moons, but Jupiter itself is still WAY too small for any hope of seeing color details.

I'm going to return to my original question. Because of some of the comments I see here, I still wonder if I am using this telescope wrongly. The slidey thingie into which the eyepiece is inserted is adjusted so that several inches of the slidey thingie are protruding from the fat part of the telescope.

I was given this telescope about 3 months ago and part of my problem is meteorological. The Pacific Northwest is a wet, cloudy place. This time of year there are several nights per month in which we could not even detect the presence of a full moon, so thick is the cloud cover. No more than a handful of nights per month present any opportunity to see anything. Right now, the National Weather Service says it will rain constantly until at least next weekend.

I do have a nice neighbor with a telescope I have not seen. Perhaps he can coach me. I think I am focusing this telescope wrongly.

Well Supe it does take a little effort even with a refractor. Several conditions impact on our ability to "see" the stars. Humidity is an invisible killer so even on a night when the sky looks clear the seeing can be poor.

This site gives an estimate of the conditions in your area:

https://www.cleardarksky.com/csk/index.html

You need to dial in your location.

Beyond this you need to ensure that your scope is setup properly. Here is the online manual

https://www.manualslib.com/manual/1807283/Celestron-Starsense-Explorer-Dx-102az.html?page=4#manual

The slidey thingie is the Focuser and shouldn't need adjustment but check to make sure it isn't loose. You can use the scope during the day to check focus.DON'T POINT IT AT THE SUN.

Pick a tree top or something else way off in the distance and play with the focus. It's alot easier to do in daylight DON'T POINT IT AT THE SUN.

If you can't get sharp focus then there is something wrong in the light path and the scope may need to be collimated. Rare but it could happen.

https://www.ozscopes.com.au/collimating-a-refractor-telescope.html

masraum 12-18-2021 07:15 AM

Quote:

Originally Posted by Superman (Post 11550444)
Steve/masraum sent me a PM and generously offered to help me out. Pelicanheads have made me feel proud for twenty years now, and this is the latest instance. Thank you, Steve.

I'm just trying to pay forward the generosity that I've been a recipient of over the years here. I've got a long way to go.

Quote:

I think I am using my telescope wrongly, and I wonder if I am focusing on the wrong plane. Flatbutt says stars jumped out of nebula. Eric says my magnification should be around 66/1. Pazuzu says color filters can help. Here's the deal: Color filters will not help me because the image would need to be several times larger in order for me to see anything larger than a spec. If I focus just right on Jupiter, I can see it has moons, but Jupiter itself is still WAY too small for any hope of seeing color details.
Seeing color is tough, and when your magnification is still pretty low, even tougher. It's a balancing act. For bright objects like Jupiter, Saturn, and on rare occasions Mars you can see variation in color or brightness. At too low of a magnification, they are too bright (and maybe too small) to see much variation. As you magnify, the brightness goes down, but then at some point, they get too dim to see much color variation.

Quote:

I'm going to return to my original question. Because of some of the comments I see here, I still wonder if I am using this telescope wrongly. The slidey thingie into which the eyepiece is inserted is adjusted so that several inches of the slidey thingie are protruding from the fat part of the telescope.

I was given this telescope about 3 months ago and part of my problem is meteorological. The Pacific Northwest is a wet, cloudy place. This time of year there are several nights per month in which we could not even detect the presence of a full moon, so thick is the cloud cover. No more than a handful of nights per month present any opportunity to see anything. Right now, the National Weather Service says it will rain constantly until at least next weekend.

I do have a nice neighbor with a telescope I have not seen. Perhaps he can coach me. I think I am focusing this telescope wrongly.
Yes, it's tough when the weather doesn't cooperate. It's a running joke that when you get new astronomy equipment, it's guaranteed to be cloudy/rainy, and often, the more you spent, the longer the weather will suck.

I would assume your scope should look a lot like this.
https://nimax-img.de/Produktbilder/b...-DX-102-AZ.jpg

Here's a generic refractor diagram that lists the major parts
https://www.popastro.com/main_spa1/w.../Refractor.jpg

There should be the main OTA (optical tube assembly) which is the tube that's got the objective lens and focuser. Then the diagonal should be inserted into the small end where the focuser is. It's possible to not have a diagonal, but I think that would be a bit unusual. Most refractors like that use a diagonal. Then the EP should be inserted into the diagonal. If you don't have a diagonal, that could certainly cause issues with getting things into focus because the length of the diagonal is part of the optical path. Without it, you may never get things into focus.

You should only have to focus initially, and then if you change eye pieces. Put in your eye piece, find a relatively bright star (but probably not the brightest in the sky) and then focus until the star is a sharp pinpoint. Anything in the sky should then be in focus (since everything in the sky is essentially at infinity).

As far as what you can expect to see of Jupiter when you can get the magnification up there, this is a decent approximation of something that would be a pretty good view. (it's almost impossible to compare photos to what you see with your eyes) On occasional when there is exceptional seeing, you can see more detail
https://cdn.fstoppers.com/styles/lar...er-stack50.jpg

When I've seen the GRS (Great Red Spot), it's usually looked more white. I once saw a hint of pink. Most of the time, when I see it, it looks more like someone took a bit out of the color band that it is embedded in. This photo has a lot of detail which we're pretty unlikely to see, but it has some aspects that to me demonstrate well what I think you would see. The lack of detail on the right hand image (and maybe a bit less, like the small spots wouldn't be detectable) is most closely representative of what I see, mostly just bands of various brightness. I've never seen the GRS look like the image on the right. When I've seen it, it looks more like the image on the left, where there's a dark band, and the spot practically blends in with the light band that it's near. And the dark band looks like someone has taken a bite out of it.

http://forums.pelicanparts.com/uploa...1639842553.jpg

This is reasonably representative of what you can see of saturn. It's mostly just going to be bands of color, and then the "cassini division" (gap in the middle of the rings.
https://i2.wp.com/astrophotography-t...09668dff_o.png

I've seen a view like ^that^ of Mars once, and to see that, I was at 300x magnification and the atmospheric conditions were just right. Mars is a tough subject.
The view of Jupiter in that pic would be decent too if the GRS wasn't actually red. It is possible to see the shadows of Jupiters moons when they cross over Jupiter, but you have to be looking at the right time to see them.

I don't know that you'll ever see color in any nebula.

Superman 12-18-2021 08:02 AM

Thanks fellas. This is all very helpful. I still think I am doing something wrong. In the image posted by Steve showing Jupiter and four moons, Jupiter is fairly big and we see lines on it. In my telescope, according to my recollections of when I have been able to use it, Jupiter is so small there is no hope I would see lines no matter how sharp the image.

In the cutaway diagram of the refractor telescope posted by Steve, most of the focuser is inside the telescope body. When I have viewed Jupiter, the focuser has been extended nearly as far out as possible. Several inches. So....I am wondering if there are two planes which can be brought into focus. If so, then I am likely on the wrong one.

BTW, I have the manual but it is only four pages. The telescope looks exactly like the first photo in Steve's last post. It is assembled properly, but I just think it may be improperly focused. I will play with it at my next opportunity. Right now, it is raining softly with wind gusts to 25 mph. I know better than to point it at the Sun. Right now, I would have little idea where the Sun even is. :)

Eric Hahl 12-18-2021 08:36 AM

You’ll never see the kind of detail shown in those photos. Well, maybe with a 20” objective. It’s trickery. Each of those photos is a stack of images taken with a video camera. Software picks out the sharpest images and aligns, stacks them for better contrast. Sometimes 1000’s of images are in the stack.
Our eyes can’t collect data and stack like that. Once the photon is received it is gone and on to the next.
My best views of Jupiter and Saturn were through a 16” reflector I had. I could make out that Jupiter was pinkish, could see the Great Red Spot when it was reddish and could see some darker belts but nothing like the sharpness shown in the photos above.
Saturn is the real treat to view. It has less cloud detail than Jupiter but the rings! They change throughout the years as we orbit and it orbits.

Keep in mind, even at 300x these planets are 500 million and 1 billion miles away. They will be tiny in an eyepiece. If you were to measure the diameter they probably would be about 1/8th inch.

Superman 12-18-2021 08:49 AM

Thank you, Eric. All of this is helpful.

I need another expensive hobby like I need kick in the head. ;)

I was able, one night, to barely make out the rings of Saturn. Saturn was more than just an oblong thing. I could actually see some space between rings and planet. So perhaps I am not focusing incorrectly.

Eric Hahl 12-18-2021 08:55 AM

Sounds like just the limits of the equipment then.

Superman 12-18-2021 09:03 AM

I accept that. But...somebody said they saw stars poking through a nebula with a "102." I am doubtful I could do that with mine, but I will keep trying.

Eric Hahl 12-18-2021 12:48 PM

Probably Orion.

masraum 12-18-2021 01:24 PM

Quote:

Originally Posted by Eric Hahl (Post 11550862)
Probably Orion.

Yes, it was the trapezium that Flatbutt mentioned.

flatbutt 12-18-2021 02:10 PM

Quote:

Originally Posted by masraum (Post 11550893)
Yes, it was the trapezium that Flatbutt mentioned.

Yes it was. It was an extra ordinary night with excellent seeing. The air was bone dry, no wind and freezing cold.

RNajarian 12-21-2021 11:45 AM

Has anyone/Can anyone image Cosmos 482?
 
Not exactly a traditional celestial body. . . but I have been fascinated with the failed 1972 Soviet Venus probe currently in a highly elliptical orbit (perigee 128 miles, apogee 1271 miles). I’ve tried to spot it in the evening sky when it is over my location and near perigee to no luck.

https://www.n2yo.com/satellite/?s=6073

Well respected photo astronomer Ralf Vanderbergh has been able locate and photograph the spacecraft. There below are a couple of examples.


https://en.wikipedia.org/wiki/Kosmos_482

https://youtu.be/QHsHrL-DnEQ

http://forums.pelicanparts.com/uploa...1640119159.jpg

http://forums.pelicanparts.com/uploa...1640119493.jpg

Eric Hahl 12-21-2021 11:53 AM

Looks like a tough target to track down. Thanks for sharing.

masraum 12-21-2021 01:26 PM

I've seen a bunch of satellites when observing, especially with binoculars where you get a wider view. Usually, they shoot past and are little more than a tiny spot (looks like a fast moving star).

I've seen Iridium flares back when they were a thing.

I've seen the ISS several times including with a scope at relatively low power once where I was able to see structure and even color. That was very exciting.

MBAtarga 12-21-2021 06:34 PM

You can sign up with NASA to get SMS texts for when the ISS is visible in your area. We've seen it dozens of times here.

Eric Hahl 12-22-2021 07:22 AM

My portable astro-photo setup is coming along. Scope arrived a few days ago and the mount yesterday.

Should be a nice widefield imaging setup. William Optics RC71, 350mm focal length @ f4.9 and an iOptron GEM 45 mount. The included (as measured) periodic error graph for the GEM 45 shows less than 5 arc seconds and about 6.2 peak to peak...impressive.

Camera should be here soon. Now, if that weather would just cooperate.

The mount looks tiny sitting on my old pier, lol.

http://forums.pelicanparts.com/uploa...1640189797.jpg

masraum 12-22-2021 07:24 AM

Quote:

Originally Posted by Eric Hahl (Post 11554021)
My portable astro-photo setup is coming along. Scope arrived a few days ago and the mount yesterday.

Should be a nice widefield imaging setup. William Optics RC71, 350mm focal length @ f4.9 and an iOptron GEM 45 mount. The included (as measured) periodic error graph for the GEM 45 shows less than 5 arc seconds and about 6.2 peak to peak...impressive.

Camera should be here soon. Now, if that weather would just cooperate.

The mount looks tiny sitting on my old pier, lol.

http://forums.pelicanparts.com/uploa...1640189797.jpg

That's a sexy looking bit of kit you've got there, sir!

Pazuzu 12-22-2021 02:52 PM

Quote:

Originally Posted by Eric Hahl (Post 11554021)
The included (as measured) periodic error graph for the GEM 45 shows less than 5 arc seconds and about 6.2 peak to peak...impressive.

Test that, all of the iOptron PE graphs I've seen end up being WAY optimistic compared to the actual usage. I believe that they even state in very tiny letters that they measure the worm/spur gear alone, in a lab condition. Once you install them on shafts, and add motor drives and timing belts, bearing sag, mount sag, etc they show much worse. A smooth PE that is +/- 50 arcseconds is better than a choppy one that is +/- 10 arcseconds.

flatbutt 12-23-2021 04:57 AM

Quote:

Originally Posted by Eric Hahl (Post 11554021)
My portable astro-photo setup is coming along. Scope arrived a few days ago and the mount yesterday.

Should be a nice widefield imaging setup. William Optics RC71, 350mm focal length @ f4.9 and an iOptron GEM 45 mount. The included (as measured) periodic error graph for the GEM 45 shows less than 5 arc seconds and about 6.2 peak to peak...impressive.

Camera should be here soon. Now, if that weather would just cooperate.

The mount looks tiny sitting on my old pier, lol.

http://forums.pelicanparts.com/uploa...1640189797.jpg

WO makes pretty stuff with outstanding optics.

flatbutt 12-26-2021 06:26 AM

Webb is on it's way!

https://www.jwst.nasa.gov/content/webbLaunch/whereIsWebb.html


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