Visable objects with 5 inch Reflector

[redshifter]

Example: With the scope I have now I would get 158x magnification using a 8mm eyepiece and 2x Barlow. With the Celestron 5 SE with the same eyepiece and Barlow I would get 317x magnification which is a waste because the max you would ever get out of the scope is 250x.

Keep in mind getting 250X out of almost any scope take a very stable atmosphere. Most nights you'll be lucky to get half that before the image breaks down because of the seeing. This is yet another reason to take it slow and work on getting the most out of the scope you have. Once you figure out what your local atmosphere will give you and what type of objects you spend the most time viewing, you'll be better able to make the most informed choice you can. High magnification capability is nothing if your local sky conditions rarely allow it. I have a 10" dob, and with my highest power eyepeice + barlow, I can get up to 320X. In the 10 years I've owned my scope, sky conditions have allowed me to use that power about 3 times, and then only on objects that look good at that high of a power - mainly planets and double stars. I don't spend a lot of time viewing doubles though. 75% of my viewing is at 30x or 70x.

[Adamsavage]

Well so much for leaving...I couldn't resist the temptation to reply to Rick basically calling out the "evil salesman"..He really is a nice guy and was very helpful to me today. Explain what you mean you can only reach a certain power with your scope. How do you know what the air will allow and what it will not ?

[Hornblower]

Well so much for leaving...I couldn't resist the temptation to reply to Rick basically calling out the "evil salesman"..He really is a nice guy and was very helpful to me today.

Make sure you pass the word about this salesman. He is someone to be treasured.

Explain what you mean you can only reach a certain power with your scope. How do you know what the air will allow and what it will not ?

A perfect telescope in perfectly still air makes slightly fuzzy images because of limitations imposed by the fundamental properties of light. For a 5" scope the fuzziness starts becoming visible about 250x, and forcing it higher just enlarges the fuzzy pattern without revealing more detail on low-contrast objects such as the surfaces of the planets. You can actually lose the ability to see some details that are barely visible at 250x if you go higher. An exception is a high-contrast object such as an extremely close double star. Here you might be better able to see the elongation of the overlapping fuzzballs if you go to still higher magnification.

If the air is turbulent you will start seeing fuzziness at lower power, and pushing it up to the nominal maximum at 250x may initially seem futile. Here a patient and skilled observer will hold out for fleeting moments of steadiness in the midst of the turbulence and get a glimpse of the finer details.

The size of the fuzz pattern is inversely proportional to the aperture. Atmospheric conditions permitting, a 10" scope can deliver 500x.

Experience and persistence will enable you to recognize more detail when you push the scope to its limits. Experienced observers see faint but real details where beginners initially see only a featureless blob. Avid observers of the planets with large telescopes live for the fleeting moments of good seeing in which their scopes can deliver the goods.

[redshifter]

Explain what you mean you can only reach a certain power with your scope. How do you know what the air will allow and what it will not ?

Basically, a scope is capable of around 50X per inch of aperature based on optical quality and optical laws. However, atmospheric conditions IME rarely allow even half of that, and most of the time even less.

You'll be able to tell what the air will allow on any given night simply by trying out increasing powers until the image gets fuzzy/blurry/wavy and won't focus. These optical distortions are caused by unstable air. In my area sometimes these effects are readily visible at only 70X on some nights. Remember that the scope magnifies both the good (the object you wnat to see) and the bad (instability in the air).

In my area, the few times I can get out in winter, poor seeing and high humidity means I can rarely get over 100x, 10X per inch of aperature. In summer, there's a period of stable air late July through August where 250X is sometimes possible - 25X per inch of aperature. So you can see that even the best nights won't come close to what a good scope is capable of optically. This is yet another reason why mount stability is more important than wiz bang optics - it's rare that you get all your optics can provide anyways(though the results are stunning on those rare nights), but an unstable mount can ruin the observing experience any night.

For more, search on atmosperic seeing and transparency. Here's a good start: http://www.cloudynights.com/item.php?item_id=1252

[Adamsavage]

Experience and persistence will enable you to recognize more detail when you push the scope to its limits. Experienced observers see faint but real details where beginners initially see only a featureless blob. Avid observers of the planets with large telescopes live for the fleeting moments of good seeing in which their scopes can deliver the goods.

This is something I learned the other night, I kept staring at the object and eventually I managed to get a better view of what I was trying to see. This shows me that I can really get alot out of my scope with just stock eye pieces. I'm waiting for the next clear night to try out my new eye piece and Barlow. I should still have a wider field of view even with the 8mm, as it has a 68 degree field of view and my stock 10mm has a 50 degree field of view. This field of field will be reduced by a factor of 2x with the Barlow if memory serves me correct.

[redshifter]

This is something I learned the other night, I kept staring at the object and eventually I managed to get a better view of what I was trying to see. This shows me that I can really get alot out of my scope with just stock eye pieces. I'm waiting for the next clear night to try out my new eye piece and Barlow. I should still have a wider field of view even with the 8mm, as it has a 68 degree field of view and my stock 10mm has a 50 degree field of view. This field of field will be reduced by a factor of 2x with the Barlow if memory serves me correct.

One good way to tease more detail out of an object is by using averted vision: http://en.wikipedia.org/wiki/Averted_vision

[Hornblower]

One good way to tease more detail out of an object is by using averted vision: http://en.wikipedia.org/wiki/Averted_vision

That is for seeing extremely faint objects that are not bright enough to register in your central vision. I don't think it applies to low contrast details on a bright object such as Jupiter. There you need all the resolution your central vision can muster.

[RickJ]

I'm glad to learn I can add that store to the unfortunately rather short list of of good local stores. None in any town I lived in was any good. Selection limited, knowledge low, and they severely over rated their lines as to what you could do with them right out of the box.

I don't know what the focal length of your scope is but I rarely use an eyepiece of shorter focal length than 16mm. For higher power I use a high quality barlow. Doubles my eyepiece collection (if you pick the right ones that don't duplicate) and costs no more than one eyepiece. I'm not all that sold on wide field eyepieces, at least for fast f ratio scopes. Unless you buy very expensive ones the edges of the field are rather distorted, especially faster than f/6. My main eyepieces are Clave orthoscopic eyepieces I bought back in the 50's with only a 45 degree field of view. I find them sharper than any of today's eyepieces, even today's orthoscopics or other designs costing many hundreds of dollars. Today a basic 50 degree plossl is the best bargain but don't begin to match my old orthos in detail nor brightness. Only if the mount is poor so it doesn't move smoothly or easily would I want wider but that might be your case.

A 5" reflector on a decent mount (unless a dob that can be hard to find) can give your years of viewing pleasure without running out of objects to see. You just have to learn the tricks of dealing with the LP you have. As I said I worked from my apartment lot with its halogen lights until I screwed up and didn't get neighbors involved and they called the cops thinking a scope pointed up looked into windows.

Do call the club, tell them your circumstances and give them a chance to help. Hands on help will speed things up greatly. I had to arrange to be driven 5 hours to a club in 1957 but learned more in two hours there than I had in 3 years on my own with books and phone calls to an amateur in that club.

Rick

[Adamsavage]

I have a 5 inch with a focal Length of 650mm or F5. Here is my scope Sky-Watcher Black Diamond

EDIT: I found where a friend of mine lives outside the city on Google Earth. I've been to his house at night, and it's amazing how much of a difference there is in the sky. It's like comparing the sky in Downtown to the sky in Kanata. I used the ruler on Google Earth and I was able to measure a distance of 14-15km from the City lights. So only 14-15km outside the city and you can start to make out the Milky Way in the sky. It doesn't take much for the sky to darken at all, however even 14km away from the city you can still see the distant glow of the city lights, however it's just above the tree line.

[redshifter]

I have a 5 inch with a focal Length of 650mm or F5. Here is my scope Sky-Watcher Black Diamond

EDIT: I found where a friend of mine lives outside the city on Google Earth. I've been to his house at night, and it's amazing how much of a difference there is in the sky. It's like comparing the sky in Downtown to the sky in Kanata. I used the ruler on Google Earth and I was able to measure a distance of 14-15km from the City lights. So only 14-15km outside the city and you can start to make out the Milky Way in the sky. It doesn't take much for the sky to darken at all, however even 14km away from the city you can still see the distant glow of the city lights, however it's just above the tree line.

Wait till you get to a true dark sky site 50-60 miles or more away from any city/town. It will amaze you!

[Adamsavage]

Wait till you get to a true dark sky site 50-60 miles or more away from any city/town. It will amaze you!

Well I have a better shot at being able to do this, the salesman at the scope store doesn't live very far from me. He said we could both go to a observation outing with one of the clubs in the city. He even offered to pick me and my scope up. I've never seen the sky any darker then what I can see 15km outside the city. So I have no idea what I would be in for.

[RickJ]

You are starting to see how the locals will help you. You've now also seen why I said going nearby dark area wouldn't help. You have to get out of the light dome itself to see a true improvement. Otherwise learn to view from your current location rather than lug everything with difficulty.

With that scope you don't need a mount. I use a 600mm fl 6" without one all the time. With, say a good 25mm to 30mm eyepiece and a lawn chair you are ready to explore the universe. While I have scopes capable of gathering far more light and at focal lengths of over 3600mm, the scope I use most is that hand held 6". Curl up in a lawn chair, if in light pollution throw a blanket over my head to shield ambient light and I'm traveling through the universe.

Rick

[Adamsavage]

I managed to catch a small window of clear sky last night. The sky cleared up for a couple hours and I was able to go out, and test the new eyepiece and Barlow 2x. Jupiter was already below the horizon by this point, Saturn however was still coming up. I was able to get a pretty good view of it. I tried to focus on it with just my stock 10mm and it was really hard to get my eyes to focus on it. I switched it with the Baader Hyperion 8mm and I was able to focus on it very quickly. Then I compared Saturn with the Barlow 2x. I used both eyepieces and it was pretty close to the same size. The downside to the 10mm is the field of view was small, the downside to the Baader Hyperion is that it seemed to cause a circle of light in the middle around Saturn. The stock 10mm did not. The plus side is of course the wider field of view, I didn't have to adjust the scope as much. I can't wait to try it out on Jupiter, it's closer then Saturn so it should appear larger in the eye piece. I'm probably going to see alot more detail as well.

Rick: I'm starting to lean away from getting that 5E scope, now that I'm starting to see what my scope can show me. I think the tie breaker is going to a very dark area, and trying out different scopes. The couple spots I was looking at on google map would be 2 light pollution zones from where I live now. I'm currently right on the edge of the white and red zone. I go up the road about 500 meters and I'm in red zone. This would explain why the big park just up the street from me seemed darker then it is compared to my general backyard area.

[RickJ]

Good. It is very foolish to buy without attending a few star parties. Until then you are working in too much ignorance to make a good decision. All scopes are a compromise and you have to decide which you can live with and which you can't. Until you can recognize these you aren't ready to buy much of anything.

I've never seen that new eyepiece so can't help there. Don't see how it would have a hot center at 8mm that shouldn't happen. Slightly fogged eyepiece could do it. Happens in the cold sometimes.

Rick

[Allanf]

I know you guys are right about being in a club but I sympathise with Adam. Those of us in the cold north/northeast climates don't have much in the way of star parties in the winter due to the temperature and almost constant cloudy skies. And if Adam is as really, really busy as I am, and also watching his pennies and wary of the hype in the ads on-line, or in Astronomy Magazine, etc. and afraid of dumping $100 to $1,000 into the wrong eyepieces - he needs the very best advice out there. I got lucky and found someone (on-line) with many years of observing experience and the exact same refractor scope as me who has shared freely. Based on his advice i put some money into pretty decent 32mm, 14mm, 5mm eyepieces and a Barlow, all U.W. but I don't know how to advise Adam regarding his reflector. By the way I wish I knew how to pronounce Betelgeuse and some of the other star names. LOL!

[RickJ]

I live in northern MN at 47N but have helped hold several star parties for hardy folk up here.

Problem with long distance advice is they don't have your conditions. That can alter advice considerably. Also what top notch gear one person loves others will find ill suited to them. Much about telescope gear is very personal making recommendations without actually trying often a great way to go wrong with confidence. Nor can they give the hands on advice, by long distance, that most beginners need. Most buying without attending a star party or two usually buy in severe ignorance of telescopes in general let alone the many differences between them. Just looking in a store doesn't cut it in my opinion. You have to see how they work for you under real skies. Only about 20% who buy this way are satisfied with their purchase after attending their first star party, at least in my club. Those who are satisfied usually, not always, have purchased a good quality Dob mounted Newtonian reflector. We've had folk drive thousand miles to attend NSP to see and learn about the vast variety of equipment out there and try it under dark skies. Most leave with a very different opinion of what they want after all. Usually something they never knew existed. The right gear will last you a lifetime. Wrong and it will show up in the used market or get stuck in the back of a closet or storage locker. A local storage place here even has a junk scope in their example of what is typically stored in a unit.

Rick

[Adamsavage]

I was thinking of possibly a Dobsonian type scope for an eventual future upgrade. The local shop has one you can rent for a week, so I may or may not try that and see what I think of it.

[Adamsavage]

This is the scope I have my eye on right now, I've been reading up these scopes and I've heard alot of praise about them. I picked it because it's only $200 more then the 8 inch. It's starting to get on the heavy side for me, so I was also thinking of getting or making, some kind of buggy that would make it easier to move around. The reason I want to get a computerized scope is so I'm not always having to make adjustments to the object in site. I still have yet to go to a star party to try out other scopes to get and idea of the differences. For now, I'm still going to be making the most out of my 5 inch, and I'm hoping with spring around the corner, I will get better sky conditions at night. I'm thinking of renting the 8 inch non goto Dobo to get a feel for what the scope is like, and then I can go from there.

[RickJ]

1) You haven't been to a star party yet. In our club, as I've said before, 80% find they bought the wrong scope when they do it that way.
2) Do you understand the compromises you make with this scope.
3) An equally portable scope with more light grasp and resolution can be had for less than half that cost.
4) you can put your current scope on a home made Dob mount for well under $100 and with proper eyepieces get performance equal to the Celestron assuming its optics are decent.
5)It should have been easy, even for a beginner to see a lot of detail on Saturn. We used similar scopes in super lit Mall parking lots to show Saturn to the public and they had no trouble at all seeing far more detail than you report. Something is still wrong with you setup likely similar issues would plague any new scope so your first chore is to get those solved.

Throwing more money at it at this stage is usually a total waste from the experience of those I saw at Hyde Memorial Observatory in the 27 years I served as a supervisor there. We saw folks like you every week. They never came to the club, tried to solve issues with new gear when they really needed a new approach to their old gear which the club would have given them but they never gave it a chance.

Rick

[redshifter]

For now, I'm still going to be making the most out of my 5 inch, and I'm hoping with spring around the corner, I will get better sky conditions at night. I'm thinking of renting the 8 inch non goto Dobo to get a feel for what the scope is like, and then I can go from there.

This is good. Also, get thee to a star party! Try out as many different scopes as you can before buying anything. Personally, I'm a fan of the 'non goto' dobs. IMO finding objects myself and learning the sky is half the fun.

[Adamsavage]

This is good. Also, get thee to a star party! Try out as many different scopes as you can before buying anything. Personally, I'm a fan of the 'non goto' dobs. IMO finding objects myself and learning the sky is half the fun.

You got a point there, I could always keep my current to learn how to find the objects on my own. I'm making excellent progress with my scope with the help of my Bino's (I really do like them, the optic quality is something else), I was able to find the Andromeda Galaxy with both today before the moon came up. I couldn't find it at first due the moon being out and making the sky to bright. Then tonight I got out before the moon came up when it was still dark outside. I went from Mirach, then went over and carefully followed the faint stars. I then pointed the scope down some and I noticed something just on the very edge of my field of view. I moved towards it and focused it and sure enough it was the Galaxy. The trick was to have my scope act like my bino's. I loosened the horizontal movement knob and the Vertical movement knob. This enabled me to freely move the scope with similar to how I would with bino's. Now that I know where to point I should be able to pull it off again, it will get easier each time I do it. That was the hardest object I've ever had to find. I'm little a surprised that I was able to see with just my Bino's.

[RickJ]

Up here there's a commercial for the Minnesota State Lottery in which a guy wins a million bucks and has an ice fishing mansion. He has a servant to catch his fish for him. To me that's what a go-to scope is all about. Same as with someone else catching your fish you learn nothing about finding fish with a servant to do the work or your way around the sky with a go-to scope. Binoculars and a planisphere are the two best tools for that. BTW, from a dark site M31 is an easy naked eye object.

While the goto of the Celestron SCT's is fairly good you still need to know the sky well enough to find the needed reference stars. Then with a low power eyepiece the object will be in the field somewhere the majority of the time. If you follow the setup exactly. From my experience with beginners at the public observatory I worked with this was much harder than it sounds. I have 10 scopes, only one of which is go-to. That's because it is my imaging scope and is run from inside the house. With winter temperatures commonly at -25F and usually a few at -40F working inside is the only way to do it. It's setup is under computer control so it never misses a step and is accurately aligned to a few seconds of arc with a mapping program that takes into account how the telescope and its mount sag when pointed in different directions as well as how the atmosphere displaces the object due to refraction. Yes these are great enough if not compensated for to move the object out of my field of view. Yet just to get that stability the cost is over 5 figures! Imagine the flex in the one armed SCT! Fortunately they use an alt azimuth mount, ill suited for imaging without a field rotator, which keeps the scope's CG pretty much in one place. Put it on a wedge for long exposure imaging and you have serious problems.

Again, just part of the compromises involved in all scopes.

In the field I'll guarantee you that redshifter will have his 10" dob set up and be observing long before you have just gotten the parts assembled, leveled and north defined for a go-to SCT. And that's before you still have to find, center and enter your reference stars. With a dob you just drop the box any old way then drop the tube onto its altitude bearings and start observing. All held together by gravity with nothing to adjust, tighten or anything (some have a tension spring to adjust, most don't). Less than a minute after hauling both out he's observing. A go-to user is still trying to get the screws in in the dark with a flashlight in his teeth while cussing up a storm. I hear this every star party I go to even by some experienced observers. Looks good in a store but under a dark sky with fingers numb from the cold or in thick gloves it's a whole different story.

At a star party you can help assemble and use many different scopes in the dark. You'll soon be seeing that often appearances of simplicity and even portability aren't reality.

Rick

[Adamsavage]

I do have plans to rent out a 8" dob and see what I think of the scope, the next star party isn't till April 28th so there is still a few months before I get a chance to try out other scopes. I've currently leaning fairly heavily towards a dob right now. For $60 more I can get a go to dob (If decide that's what I want) that is 10" vs a 8" Cassegrain go to. I'm getting 40% more light gathering for only $60 more, that sounds like a pretty good deal to me. Plus when I do get my upgrade of a scope in a few months down the road, and I've rented a scope from the Evil Salesman (had to put that in there) then I get a $40 credit towards the purchase of a scope. I may even stick with a human powered dob, I can get a 12" dob for $260 less then a 10" computerized one.

[redshifter]

I do have plans to rent out a 8" dob and see what I think of the scope, the next star party isn't till April 28th so there is still a few months before I get a chance to try out other scopes. I've currently leaning fairly heavily towards a dob right now. For $60 more I can get a go to dob (If decide that's what I want) that is 10" vs a 8" Cassegrain go to. I'm getting 40% more light gathering for only $60 more, that sounds like a pretty good deal to me. Plus when I do get my upgrade of a scope in a few months down the road, and I've rented a scope from the Evil Salesman (had to put that in there) then I get a $40 credit towards the purchase of a scope. I may even stick with a human powered dob, I can get a 12" dob for $260 less then a 10" computerized one.

Wasn't portability an issue for you? A 12" dob is a lot of things, portable isn't one of them; at least a solid tube 12". A 10" solid tube dob is about the biggest you can get until you need a larger station wagon or a van for transporting. It's great to see you considering your options. I still say buy NOTHING until you can get out to a star party and try out everything. Renting the 8" is a good idea as well.

[Adamsavage]

Yeah I was looking for portability, but at the same time I'm looking at the cost difference as well. The difference is to great to not go with a Dob. For just moving around a scope I was thinking of making a buggy of some kind, this would allow it to be moved around with more ease.

[redshifter]

You might be a good candidate for one of the truss type dobs. They break down into smaller sections and are more portable than a solid tube dob. However, with a truss type scope, you give up some of the ease of setup: For me (as RickJ alluded to earlier) it's just a matter of plunking down the mount, setting the tube on the mount, and I'm observing. I've been to locations shared by others where I was set up and observing, spent an hour/hour and a half observing, then put everything away and headed home. In that time, I've seen others working on just setting up their equipment the entire time I was there.

Compromises, compromises...

[Adamsavage]

I'm thinking mostly based on the cost of scopes out there that a 10 inch Collapsible Dobsonian Telescope would be good for me. I thought about the computerized version, but there is a $560 price difference. So I may just get a normal non go to scope, I do need to rent out that 8 inch the scope store has. This will allow me to get a feel for a Dobsonian, and then I think I will go from there. How easy are they to adjust to keep on the target ? I would mostly be using it for planets, Galaxies, and nebula's for now. I also have to check for an open observation meeting of the local club. I'm pretty sure I will be getting a Dobsonian in the future, what one or type is not known for sure yet. I know I wont get a Cassegrain, they are simply to expensive for me. Highly portable yes, but the pricing is simply to much for me. I think will just come up with a way to make a Dobsonian easier to move around if I want portability. For going to darker area's, I will just have to get a friend with a Van or something to come with me to one.

[Adamsavage]

Ok so I've tried a 8 inch Dobo (rental), and a 8 Cassegrain that is motorized but not a go to. It simply keeps the object in focus, and I just love how fine the the adjustment knobs are. They are right in front of me and I don't have to reach around in a awkward position. The Telescope store in Ottawa has a used one (the one I tried out) for $600. I think I might get that one, I like because it can me motorized or you can use it like a normal scope as well.

[Adamsavage]

Here is the specs to the scope I was trying out.

Meade 2080 8" Schmidt-Cassegrain, 2032mm focal length, f/10

[ShinAce]

I live a 5 minute walk from the museum of science and technology. It's right next to the elmvale bus station.

http://www.sciencetech.technomuses.c...bservatory.cfm

Be sure to click on astronomy programs, as they frequently open the dome to let amateurs have a peek through the scope. When they do, amateur astronomers themselves bring their own scopes and are more than willing to chat it up. While you're there, be sure to ask about other star parties. It is finally warm enough to enjoy a dark night without freezing fingers and nose.

I know this because we stopped in to the observatory on an observing night for my buddy's bachelor party. We has dressed up in a spacesuit, and that alone got him to skip the line and see through the big scope.

Now, don't do what we did and non chalantly drink in the parking lot....