Re: Auto Find Feature that could still allow for equatorial rotation...
I have been doing a bit of research on the web and noticed that there are some Meade scopes that have what appears to be a wedge mount...I would like to get a scope that could allow for equatorial rotation but still maintain it's auto find features? I am heavily leaning towards a Nexstar 8 or Nexstar 11 for the ease of use and quality...However, I loose the auto find feature as soon as I put it on a wedge.
From all my research over the past few years, I have nailed down my buying decision based on the following priorities: #1 Ease of use (Auto Find Features)...This is absolutely the most important thing because this is my first scope. #2 Quality of image...I want to make sure I don't under buy...I am afraid I might get bored if the image quality isn't very good. #3 Photography...Long term goal.
I would appreciate any opinions of other scopes that might meet my needs. Thanks, JohnRen
John, I have used the Meade LX200 series scopes on various occasions. The GOTO feature does indeed function while the scope is mounted on a wedge, as does the Nextar's as long as you don't try to use GPS. This is because the GPS computer thinks that the scope is level while in fact it is tilted at 40*. I would start with the scope mounted without the wedge. You will lose nothing in terms of image quality, but it will be easier to use the scope. Then as you progress toward your ultimate goal of astrophotography, you can mount it with the wedge. You may want to get involved in one of the local astronomy clubs. The members of these clubs will be more than happy to help you decide on a scope as well as help you learn the night sky. You may find that you don't want to have the scope find everything for you, once you learn how to navigate the night sky. The quality of star atlases that are out there means that you will only need a rudimentary knowledge of the positions of constellations, the atlas shows you the specifics. Greg --- John Renstrom <JohnRenstrom@hotmail.com> wrote:
I have been doing a bit of research on the web and noticed that there are some Meade scopes that have what appears to be a wedge mount...I would like to get a scope that could allow for equatorial rotation but still maintain it's auto find features? I am heavily leaning towards a Nexstar 8 or Nexstar 11 for the ease of use and quality...However, I loose the auto find feature as soon as I put it on a wedge.
From all my research over the past few years, I have nailed down my buying decision based on the following priorities: #1 Ease of use (Auto Find Features)...This is absolutely the most important thing because this is my first scope. #2 Quality of image...I want to make sure I don't under buy...I am afraid I might get bored if the image quality isn't very good. #3 Photography...Long term goal.
I would appreciate any opinions of other scopes that might meet my needs.
Thanks, JohnRen
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John, IMO the Meade has many advantages with things like software updates, satellite auto tracking, comets and meteorites. It appears the optics of the NS 11 and the 10" Meade LX200 GPS with the new coatings are pretty equal. Imaging is the only time you will need use the polar alignment (wedge). Now having said that I must point out I'm a rookie and have just had my scope for a year. Wayne -----Original Message----- From: utah-astronomy-admin@mailman.xmission.com [mailto:utah-astronomy-admin@mailman.xmission.com] On Behalf Of John Renstrom Sent: Friday, February 28, 2003 1:15 AM To: utah-astronomy@mailman.xmission.com Subject: [Utah-astronomy] Re: Auto Find Feature that could still allow for equatorial rotation... I have been doing a bit of research on the web and noticed that there are some Meade scopes that have what appears to be a wedge mount...I would like to get a scope that could allow for equatorial rotation but still maintain it's auto find features? I am heavily leaning towards a Nexstar 8 or Nexstar 11 for the ease of use and quality...However, I loose the auto find feature as soon as I put it on a wedge.
From all my research over the past few years, I have nailed down my buying decision based on the following priorities: #1 Ease of use (Auto Find Features)...This is absolutely the most important thing because this is my first scope. #2 Quality of image...I want to make sure I don't under buy...I am afraid I might get bored if the image quality isn't very good. #3 Photography...Long term goal.
I would appreciate any opinions of other scopes that might meet my needs. Thanks, JohnRen _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy --- [This E-mail scanned for viruses by Declude Virus] --- [This E-mail scanned for viruses by Declude Virus]
I posted this Friday morning then left until now. I have been worried while gone about all the flames I would get about tracking meteorites I thank you for sparing me I'm sure because I'm a rookie. Should have said asteroid, or at least bowling balls. Wayne -----Original Message----- From: utah-astronomy-admin@mailman.xmission.com [mailto:utah-astronomy-admin@mailman.xmission.com] On Behalf Of Wayne Reese Sent: Friday, February 28, 2003 7:11 AM To: utah-astronomy@mailman.xmission.com Subject: RE: [Utah-astronomy] Re: Auto Find Feature that could still allow for equatorial rotation... John, IMO the Meade has many advantages with things like software updates, satellite auto tracking, comets and meteorites. It appears the optics of the NS 11 and the 10" Meade LX200 GPS with the new coatings are pretty equal. Imaging is the only time you will need use the polar alignment (wedge). Now having said that I must point out I'm a rookie and have just had my scope for a year. Wayne -----Original Message----- From: utah-astronomy-admin@mailman.xmission.com [mailto:utah-astronomy-admin@mailman.xmission.com] On Behalf Of John Renstrom Sent: Friday, February 28, 2003 1:15 AM To: utah-astronomy@mailman.xmission.com Subject: [Utah-astronomy] Re: Auto Find Feature that could still allow for equatorial rotation... I have been doing a bit of research on the web and noticed that there are some Meade scopes that have what appears to be a wedge mount...I would like to get a scope that could allow for equatorial rotation but still maintain it's auto find features? I am heavily leaning towards a Nexstar 8 or Nexstar 11 for the ease of use and quality...However, I loose the auto find feature as soon as I put it on a wedge.
From all my research over the past few years, I have nailed down my buying decision based on the following priorities: #1 Ease of use (Auto Find Features)...This is absolutely the most important thing because this is my first scope. #2 Quality of image...I want to make sure I don't under buy...I am afraid I might get bored if the image quality isn't very good. #3 Photography...Long term goal.
I would appreciate any opinions of other scopes that might meet my needs. Thanks, JohnRen _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy --- [This E-mail scanned for viruses by Declude Virus] --- [This E-mail scanned for viruses by Declude Virus] _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy --- [This E-mail scanned for viruses by Declude Virus] --- [This E-mail scanned for viruses by Declude Virus]
If you are really concerned about image quality, I would shy away from the Schmidt Cassegrain (SCT) telescopes. You'll get a much better image through a Newtonian. I have made several hundred newtonians, many of which are 6" f10 scopes. Almost without exception, people comment that the image through them is far superior to the image through an 8" SCT. I think you will also get a better image through a Newtonian for astrophotography, too. Many people call me prejudiced here, but my opinions are backed up by many members of the general public, who are not used to looking through a telescope. They comment freely at star parties about images they have seen in telescopes. I have also had the same comments from teachers I have worked with as they compare images. Another advantage to a Newtonian (without GOTO) is that you get a chance to be on a first name basis with the stars. You get to really know the sky, and it becomes a part of you. If you want to do astrophotography, you can get access to SPOC. Those scopes will give you a better image, and are already set up to do the job. Very careful alignment is a must for good astrophotographs. SPOC is already aligned, and you won't have to spend hours aligning to get a good shot. All the equipment is already there, too. Brent --- John Renstrom <JohnRenstrom@hotmail.com> wrote:
I have been doing a bit of research on the web and noticed that there are some Meade scopes that have what appears to be a wedge mount...I would like to get a scope that could allow for equatorial rotation but still maintain it's auto find features? I am heavily leaning towards a Nexstar 8 or Nexstar 11 for the ease of use and quality...However, I loose the auto find feature as soon as I put it on a wedge.
From all my research over the past few years, I have nailed down my buying decision based on the following priorities: #1 Ease of use (Auto Find Features)...This is absolutely the most important thing because this is my first scope. #2 Quality of image...I want to make sure I don't under buy...I am afraid I might get bored if the image quality isn't very good. #3 Photography...Long term goal.
I would appreciate any opinions of other scopes that might meet my needs.
Thanks, JohnRen
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Bravo, Brent. You speak the absolute truth, from my experience. But good luck breaking-through the slick marketing shovelled-out by the purveyors of these telescopes. I also agree that "Go-To" mounts do a disservice to users, in the long run. BUT- if someone is only going to take out their telescope 3 or 4 times a year, has the money to burn, then buying one of these might make sense. C. --- Brent Watson <brentjwatson@yahoo.com> wrote:
If you are really concerned about image quality, I would shy away from the Schmidt Cassegrain (SCT) telescopes. You'll get a much better image through a Newtonian.
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I appreciate all your responses...It is always nice to get different opinions.
I also agree that "Go-To" mounts do a disservice to users, in the long run. I must disagree to this comment...The auto find feature is what sold me on finally buying my scope...I have small kids and my wife needs me at home as much as possible...If I am lucky, I might be able to get a few hours a week to spend under the stars. The last thing I want to have to do is drag out a big scope and spend a ton of time setting it up before I can even start . Eventually, I could see me getting more into just wandering the sky, but until I have done the rounds, I need to have an instructor...Thus, my auto find feature that will make me more confident and ensure that I enjoy what little time I have to spend under the stars.
BUT- if someone is only going to take out their telescope 3 or 4 times a year, has the money to burn, then buying one of these might make sense. Actually, I view my time as money...I consider it a good investment in myself when I can make my time more enjoyable and more productive. I am also very exited about sharing time with others and being able to quickly show them things through my scope. Especially thos that might not be able to spend an entire evening with me while I scan for specific objects.
Eventually I will be more interested in just roaming the stars...Just because my scope has an auto find feature, doesn't mean I have to always use it. My priorities remain the same... #1 Ease of use...It needs to be compact, easy to set up and capable of taking me for a tour of the night sky... #2 Image quality. #3 Photography.
--- JohnRenstrom@Hotmail.com wrote:
My priorities remain the same... #1 Ease of use...It needs to be compact, easy to set up and capable of taking me for a tour of the night sky... #2 Image quality. #3 Photography.
Your criteria are valid, but I still think a Schmidt-Cass isn't the total answer. #1 GoTo Schmidt-Cassegrains offer nothing to speed set-up. Polar alignment is not a difficult operation, if you know how. Letting a computer do it for you guarantees that you'll never learn to do it quickly by hand & eye. Too, the portable fork-mount is about the last choice of the astrophotographer. You'll have a better time balancing, tracking, and loading-up the equipment weight with a heavy-duty German equatorial. Is the S-C offered in a GoTo G.E.M.? #2 Well, as Brent pointed out, a S-C will not fulfill this critera if indeed the best resolution is required. #3 See #1. Also, if the intent is just to capture images without any of the attendant activities, I fail to see the allure. I actually enjoy guiding manually-it's part of the total experience. Is this now considered weird and anachronistic? If the object is to take the exact same photo as 20 thousand other people, why not just download it from someone's website? I know folks who can find objects faster than GoTo mounts, and I myself am pretty darn competitive. Now, that said, if you do go-ahead with your intended purchase, I'm sure I'm not the only one who would be interested in just how your personal criteria were met by the instrument. Maybe Brent and I are missing your point completely. Please post your experience afterwards! To echo Kim's post, please understand that no-one is attacking you or showing disrespect toward your opinions & desires. You posted one view, we posted another. Thanks C. __________________________________________________ Do you Yahoo!? Yahoo! Tax Center - forms, calculators, tips, more http://taxes.yahoo.com/
John, Here is my experience: 1. Ease of setup. I can set up my 12.5 inch dob in less than five minutes, and be observing. My 8" refractor takes about the same time if I use the pipe mount. My 10" takes about 20 minutes. My six inch is set up in less than one minute. I am capable of taking myself on a tour of the night sky, and yes, I can usually beat a GOTO scope. I have taught hundreds of people how to do the same. It takes less time than you have already spent investigating telescopes. 2. Image quality. I'll put my 12.5 inch and my 8" up against ANY commercial SCT, regardless of aperture. I get consistent comments that the images these scopes produce are the best images at a star party. The image on planets and double stars through the refractor is top notch. There are not many better. An 8" refractor objective is within the several thousand dollars you mention. You can put the rest of the scope together for a few hundred dollars. 3. Photography. This is a matter of getting the right mount. Unless you are going to use an image de-rotator, you'll need to have an equatorial mount. The standard Meade and Celestron are not adequate for photography if you want quality images. As I mentioned before, your best bet is to use SPOC. That facility is capable of near professional quality. I realize that you have probably made up your mind on your purchase. I also realize that what I am saying will not change your mind. In astronomy, you don't always get what you pay for. However, you will get out of the hobby only that which is in proportion to your effort. Good luck in your endeavors. Astronomy is one of the most fulfilling passtimes you can enjoy. I have not found anyoner to pay me to observe yet, and I don't want to. The past tense of fun is funded. I realize that this post is a bit on the rough side. It is not my intention to put you off here. I just think you should at least hear the experience of an observer who has been at it for almost 40 years. Pleaee excuse my bruskness. Brent
My priorities remain the same... #1 Ease of use...It needs to be compact, easy to set up and capable of taking me for a tour of the night sky... #2 Image quality. #3 Photography.
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Brent said: Unless you are going to use an image de-rotator, you'll need to have an equatorial mount. What is a de-rotator? How does it work on a fork mount? Barney
Barney: If a telescope is used in alt-azimuth mode, such as a Dobsonian or a fork with no wedge (fork pointed straight-up), the field will rotate as an object is followed. Imagine the telescope facing east; an up and down motion in altitude corresponds to east-west motion on the sky. Now face the scope south, and see how an up and down motion corresponds to north-south on the sky. In the six hours from when an object rises until it crosses the meridian, the field has rotated 90-degrees. A de-rotator compensates for this, rotating the camera one revolution per 24 hrs. Equatorially mounted scopes, like Dobs on platforms or fork-mounted SCT's with wedges, do not have field rotation. C. --- "Barney B." <aaah@sisna.com> wrote:
Brent said: Unless you are going to use an image de-rotator, you'll need to have an equatorial mount.
What is a de-rotator? How does it work on a fork mount?
Barney
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Hi Chuck. Thanks. I understand field rotation but what is a de-rotator? Is it something that can be bought in a store? How would it work? Would it install between the camera and the scope? What controls it? Who makes one? ----- Original Message ----- From: "Chuck Hards" <chuckhards@yahoo.com> To: <utah-astronomy@mailman.xmission.com> Sent: Saturday, March 01, 2003 3:39 PM Subject: Re: [Utah-astronomy] de-rotator
Barney:
If a telescope is used in alt-azimuth mode, such as a Dobsonian or a fork with no wedge (fork pointed straight-up), the field will rotate as an object is followed. Imagine the telescope facing east; an up and down motion in altitude corresponds to east-west motion on the sky. Now face the scope south, and see how an up and down motion corresponds to north-south on the sky. In the six hours from when an object rises until it crosses the meridian, the field has rotated 90-degrees. A de-rotator compensates for this, rotating the camera one revolution per 24 hrs. Equatorially mounted scopes, like Dobs on platforms or fork-mounted SCT's with wedges, do not have field rotation.
C. --- "Barney B." <aaah@sisna.com> wrote:
Brent said: Unless you are going to use an image de-rotator, you'll need to have an equatorial mount.
What is a de-rotator? How does it work on a fork mount?
Barney
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Basically, it's a drawtube that rotates, driven by a stepper motor via belts or gears. Whatever's locked in the drawtube is rotated with it. They don't need active control, since they are basically just a clockwork mechanism, 1 rpd., but it wouldn't surprise me if they existed with programmable rates or scripting capability. There are commercially-made units; I think even Meade offers one for their 16" SCT when it's mounted in alt-az. mode. But I don't have the details for any off-the-shelf units. C. --- "Barney B." <aaah@sisna.com> wrote:
Hi Chuck. Thanks.
I understand field rotation but what is a de-rotator? Is it something that can be bought in a store? How would it work? Would it install between the camera and the scope? What controls it? Who makes one?
----- Original Message ----- From: "Chuck Hards" <chuckhards@yahoo.com> To: <utah-astronomy@mailman.xmission.com> Sent: Saturday, March 01, 2003 3:39 PM Subject: Re: [Utah-astronomy] de-rotator
Barney:
If a telescope is used in alt-azimuth mode, such as a Dobsonian or a fork with no wedge (fork pointed straight-up), the field will rotate as an object is followed. Imagine the telescope facing east; an up and down motion in altitude corresponds to east-west motion on the sky. Now face the scope south, and see how an up and down motion corresponds to north-south on the sky. In the six hours from when an object rises until it crosses the meridian, the field has rotated 90-degrees. A de-rotator compensates for this, rotating the camera one revolution per 24 hrs. Equatorially mounted scopes, like Dobs on platforms or fork-mounted SCT's with wedges, do not have field rotation.
C. --- "Barney B." <aaah@sisna.com> wrote:
Brent said: Unless you are going to use an image de-rotator, you'll need to have an equatorial mount.
What is a de-rotator? How does it work on a fork mount?
Barney
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If a field derotator is a 1 rpd drive couldn't one be built with a pivot and counterweights? Axis of pivot would be parallel to optical axis, counterweights would hang down to drive rotation at 1 rpd by gravity. Wouldn't want to use it in a wind, but would it work? Bill B Chuck Hards wrote:
Basically, it's a drawtube that rotates, driven by a stepper motor via belts or gears. Whatever's locked in the drawtube is rotated with it. They don't need active control, since they are basically just a clockwork mechanism, 1 rpd., but it wouldn't surprise me if they existed with programmable rates or scripting capability. There are commercially-made units; I think even Meade offers one for their 16" SCT when it's mounted in alt-az. mode. But I don't have the details for any off-the-shelf units.
C.
Hi Bill: Of course any clockwork mechanism can be designed to be powered by a falling-weight drive, but it would be hard to beat a motor/gear driven unit for compactness & simplicity. C. --- bill biesele <xmix@biesele.net> wrote:
If a field derotator is a 1 rpd drive couldn't one be built with a pivot and counterweights? Axis of pivot would be parallel to optical axis, counterweights would hang down to drive rotation at 1 rpd by gravity.
Wouldn't want to use it in a wind, but would it work?
Bill B
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Actually, field rotation is a very complicated function of altitude and azimuth. For example, exactly at the zenith, the rotation rate is infinite. Also, if your field is circumpolar, the rotation stops and reverses at two points in its 'orbit' around Polaris (its eastern and western most points). The one rpd thing would only work if your field were centered exactly on the north celestial pole (because then the altitude and azimuth would remain constant). We derived the whole thing in my astrophysics class at the U (rather nasty derivation, I needed help from the professor to figure it out). Greg --- Chuck Hards <chuckhards@yahoo.com> wrote:
Hi Bill:
Of course any clockwork mechanism can be designed to be powered by a falling-weight drive, but it would be hard to beat a motor/gear driven unit for compactness & simplicity.
C.
--- bill biesele <xmix@biesele.net> wrote:
If a field derotator is a 1 rpd drive couldn't one be built with a pivot and counterweights? Axis of pivot would be parallel to optical axis, counterweights would hang down to drive rotation at 1 rpd by gravity.
Wouldn't want to use it in a wind, but would it work?
Bill B
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Greg wrote:
Actually, field rotation is a very complicated function of altitude and azimuth. For example, exactly at the zenith, the rotation rate is infinite.
You've discovered "Dobson's Hole".
if your field is circumpolar, the rotation stops and reverses at two points in its 'orbit' around Polaris (its eastern and western most points). The one rpd thing would only work if your field were centered exactly on the north celestial pole (because then the altitude and azimuth would remain constant).
My description was very basic. I'll only disect the difficulties if someone is actually planning to buy one ;)
We derived the whole thing in my astrophysics class at the U (rather nasty derivation, I needed help from the professor to figure it out).
Are there any astronomers on-staff these days? When I went there (over 25 years ago), the place was thick with physicists, but no astronomers. Do they offer an astronomy degree yet? (BYU wouldn't take me...something about my haircut...or lack of one at the time...) Your reminder of the nuances of a field-derotator has convinced me that an equatorial mount or platform is the path I will explore on my next large scope. One less piece of hardware to have to tote-along. I will say that if you use any design by Mel Bartels, you're off to a great start if you do decide to stick with an alt-az mount & derotator. Good luck on your studies & ATMing Greg, and thanks! C. __________________________________________________ Do you Yahoo!? Yahoo! Tax Center - forms, calculators, tips, more http://taxes.yahoo.com/
Computerized field de-rotators work because they are hooked into the rest of the drive system. The computer knows the exact alt-az coordinates of the scope, so it can feed the correct rotation rate to the de-rotator. BTW, meade also makes--or at least made--a derotator for their smaller LX200's. The only consumer installable drive system that has field de-rotator support that I know of is Mel Bartels' system. Which incedentally I will be installing on the new scope that I am making. (30" f/4.23 folded dob, if anyone wanted to know). Greg __________________________________________________ Do you Yahoo!? Yahoo! Tax Center - forms, calculators, tips, more http://taxes.yahoo.com/
Bill, This design would work well in a frictionless evnironment. I fear that with any friction at all the mechanism would move in small increments that would destroy the image. It doesn't take much. Brent --- bill biesele <xmix@biesele.net> wrote:
If a field derotator is a 1 rpd drive couldn't one be built with a pivot and counterweights? Axis of pivot would be parallel to optical axis, counterweights would hang down to drive rotation at 1 rpd by gravity.
Wouldn't want to use it in a wind, but would it work?
Bill B
Chuck Hards wrote:
Basically, it's a drawtube that rotates, driven by
a
stepper motor via belts or gears. Whatever's locked in the drawtube is rotated with it. They don't need active control, since they are basically just a clockwork mechanism, 1 rpd., but it wouldn't surprise me if they existed with programmable rates or scripting capability. There are commercially-made units; I think even Meade offers one for their 16" SCT when it's mounted in alt-az. mode. But I don't have the details for any off-the-shelf units.
C.
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One of the pages on Chuck Shaw's web site illustrates a de-rotator for a tracking alt-az mount - see http://www.ghg.net/cshaw/14newt.htm and scroll down a bit. Jim Seargeant ----- Original Message ----- From: "Barney B." <aaah@sisna.com> To: <utah-astronomy@mailman.xmission.com> Sent: Saturday, March 01, 2003 12:34 PM Subject: [Utah-astronomy] de-rotator
Brent said: Unless you are going to use an image de-rotator, you'll need to have an equatorial mount.
What is a de-rotator? How does it work on a fork mount?
Barney
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John, While I agree with others about superior images in Newtonians over SCT's, I recognize your desire for portability and ease of use, so I'll not try to talk you out of pursuing a goto SCT. :o) I would be very surprised if the GPS functionality is limited to use without an equatorial wedge (I would call Celestron in California and confirm this if I were you). If choosing between Meade and Celestron, I can only tell you what I've heard (since I've not owned either). Celestron SEEMS to have a better reputation where quality control is concerned. And their drives are certainly less noisy. Before any Meade owners flame me over this, like I said, this is what I've heard over the years, and may or may not be accurate. Both companies have at times had problems with quality control, and not all SCT's that roll off either assembly line are created equal. Some resellers will test them for you for optical quality and may give you their assurances ahead of time, but you may have to pay a bit more for this service. You might want to consider the new CGE series (German Equatorial Mount -- there's a big ad in the latest S&T on pages 32-33) which would ultimately be much better when you get into photography over the fork mount. And if the choice is between 8 and 11 inches, if you can afford the 11, and are strong enough to heft it, go for more aperture (I think everyone on the list can agree with that advice). ;o) My 2 cents, Rich --- John Renstrom <JohnRenstrom@hotmail.com> wrote:
I have been doing a bit of research on the web and noticed that there are some Meade scopes that have what appears to be a wedge mount...I would like to get a scope that could allow for equatorial rotation but still maintain it's auto find features? I am heavily leaning towards a Nexstar 8 or Nexstar 11 for the ease of use and quality...However, I loose the auto find feature as soon as I put it on a wedge.
From all my research over the past few years, I have nailed down my buying decision based on the following priorities: #1 Ease of use (Auto Find Features)...This is absolutely the most important thing because this is my first scope. #2 Quality of image...I want to make sure I don't under buy...I am afraid I might get bored if the image quality isn't very good. #3 Photography...Long term goal.
I would appreciate any opinions of other scopes that might meet my needs.
Thanks, JohnRen
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My only advice, based on years of being a telescope seller, user and friend of telescope users is that if you do proceed with your proposed purchase I'd suggest you buy locally, if possible, so as to minimize any problems with repairs and returns. Patrick
Brent, Chuck, Kim and anybody else with an opinion I was of the understanding that a GPS telescope is really useful if you are moving around allot; I mean loooong distances. It you are just using it in your back yard, what good does a GPS do you if you are always in the same place? I can't see how the cost would be justified; but that is why I am asking the question, I don't know. To John One other thought. I bought a Meade 2130 5inch telescope with Autostar. It cost about $300.00. I would suggest considering something like this. I believe it would satisfy all of your (John Renstrom's) criteria. I like playing with the GOTO and allot of the time I just like pushing the tube around by hand. I figured if I didn't like the telescope, I could give it to my son and then I would have a better idea what I really wanted after my experience with the Meade. The down side to the Wal-Mart Meades is that the finder scopes are under par and the eyepieces are only .96 inch. It's a limited investment that you can chalk up to education and it is a good kids scope as well. It sounds like, John, you have been looking at telescopes for a while. If you haven't gone to a Star Party or two that would be a good move before you actually plunk down a sizeable investment. Jim Gibson --------------------------------- Do you Yahoo!? Yahoo! Tax Center - forms, calculators, tips, and more
Can someone tell me why a GPS is even needed? You don't need to know your precise latitude to polar-align. It would be useful for occultation work, especially if you travel long distances to unknown territory, but a USGS topo map works just as well. What am I missing? Thanks C. --- Jim Gibson <xajax99@yahoo.com> wrote:
Brent, Chuck, Kim and anybody else with an opinion I was of the understanding that a GPS telescope is really useful if you are moving around allot; I mean loooong distances. It you are just using it in your back yard, what good does a GPS do you if you are always in the same place? I can't see how the cost would be justified; but that is why I am asking the question, I don't know.
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Chuck, The GPS feature is the ultimate dumbing down of the whole process. You don't need to level your scope, or polar align or anything. Just plop the sucker down anywhere on the planet, power it up, and it instantly knows where it is and where to point, just like magic! Even a blind rabbit could do it (if he had opposable thumbs and the strength to lift it out of the trunk of someone's car, assuming he knew where the power switch was and could kick it on that is...). :o) Rich --- Chuck Hards <chuckhards@yahoo.com> wrote:
Can someone tell me why a GPS is even needed? You don't need to know your precise latitude to polar-align. It would be useful for occultation work, especially if you travel long distances to unknown territory, but a USGS topo map works just as well. What am I missing?
Thanks
C.
--- Jim Gibson <xajax99@yahoo.com> wrote:
Brent, Chuck, Kim and anybody else with an opinion I was of the understanding that a GPS telescope is really useful if you are moving around allot; I
mean
loooong distances. It you are just using it in your back yard, what good does a GPS do you if you are always in the same place? I can't see how the cost would be justified; but that is why I am asking the question, I don't know.
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Actually, GPS could be useful if you regularly moved the scope to various observation locations, and if it were able to provide user feedback in a practical way to set up using an equatorial wedge, like telling you how much to increase or decrease elevation, provide precise true-north alignment during the day or on nights when polaris might be obscured by clouds, etc. Once those factors are precisely set (or, on a more elaborate system, where mount leveling, the wedge angle and north orientation would be achieved by stepper motors directed by the GPS), then goto and tracking would work fine with an equatorial wedge. That may well be the next step for these guys... Rich --- Chuck Hards <chuckhards@yahoo.com> wrote:
Can someone tell me why a GPS is even needed? You don't need to know your precise latitude to polar-align. It would be useful for occultation work, especially if you travel long distances to unknown territory, but a USGS topo map works just as well. What am I missing?
Thanks
C.
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Chuck Hards wrote:
Can someone tell me why a GPS is even needed?
The only real advantage I can think of is for those wanting to find planets in the daytime or if it's nighttime and Polaris is not visible. Otherwise give me a good view of Polaris and I can have my C-8 polar aligned in much less time that the goto scopes take. Patrick
Jim Wrote:
One other thought. I bought a Meade 2130 5inch telescope with Autostar. It cost about $300.00. I would suggest considering something like this. I believe it would satisfy all of your (John Renstrom's) criteria. I like playing with the GOTO and allot of the time I just like pushing the tube around by hand. I figured if I didn't like the telescope, I could give it to my son and then I would have a better idea what I really wanted after my experience with the Meade. I have thought about buying a small cheap version of the nexstar, but as I keep asking people why they are selling these types of scopes, it almost always the same story...they are upgrading. I have several thousand dollars that I am willing to invest into my scope and despite how anxious I am to buy, I enjoy reading and learning more about this field...Also, the prices on this equipment just keep getting better and better...
Jim Wrote:
It sounds like, John, you have been looking at telescopes for a while. If you haven't gone to a Star Party or two that would be a good move before you actually plunk down a sizeable investment. Yes, you are correct, I have been reading up on scopes for over 2 years now...I really like to take my time before buying anything...I consider this a very expensive and time consuming hobby and I want to be as prepared as possible before plunging in...I consider myself a very caucious buyer and like to buy for the long-term...As for the star parties, I am very anxious about attending one...I have some friends with scopes, but I think the idea of a bunch of people all draging their scopes out for a party sounds like a total blast! I anticipate I will be that nosy person asking a lot of questions and roaming around mindlessly.
To Kim: I my bark sounds worse than my bite...I actually liked what you said...In fact, I think I was replying to Chuck's email more than yours... To Chuck: I know someday it might be nice to roam the stars and to be able to know where everything is...But until then, I must rely on the auto find feature. I don't think the auto find feature is bad at all...I compare it to calculators in the class room...when I went to school, we couldn't use calculators because the teachers felt like the students wouldn't learn how to do the math...Now days, the tests are so complicated, you would be crazy to even try to take a test without a calculator...I just think that the auto find technology is the beginning of more intelligent scopes...Having more intelligent scopes only opens the door for the lazy people like myself...and let me assure you, when I say lazy, I mean lazy! I am so lazy that I am extremely tempted by the GPS unit simply because I don' want to have to care where I set the scope up...I want to plug it in start playing without having to key in any numbers! :-)
participants (12)
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Barney B. -
bill biesele -
Brent Watson -
Chuck Hards -
Greg Taylor -
Jim Gibson -
Jim Seargeant -
John Renstrom -
JohnRenstrom＠Hotmail.com
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Patrick Wiggins -
Richard Tenney -
Wayne Reese