Looking for a Telescope for this Fall's Mars Opposition

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BReif

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Hello all:<br /><br />I am looking to purchase a telescope within the next couple of weeks, primarily for planetary viewing, but also for looking at some DSO's. I am not overly interested in astrophotography at this time, however, if the scope could be expanded for that, it would be nice for "down the road." I once had a Meade ETX 125 but the tracking motors broke, of course, past the warranty. Because I didn't save my reciept as proof of purchase, or the original shipping box, I couldn't have it repaired. It is now a 5" Mak-Cas paperweight. So, I would be looking for either something on a equatorial mount without GOTO, or GOTO that is more reliable than Meade ETX's plastic motor gears. Right now, i am lookign at Celestron's NexStar 8i Special Edition, and Orion's 100 mm ED Apochromatic Refractor. Understanding that that the 8i has 8" of apeture, vrs. the 100 mm 4", and given my wanting this primarily as a planetary scope, with some DSO's, in your opinions, which would be the better buy?<br /><br />Also, other questions: Has anyone had any experience with the Celestron NexStar GOTO scopes that can speak about their reliability? I have been unable to find anything on-line in a review about the 8i SE. Are the motor gears plastic, like the ETX, or metal, which is unlikely to break like Meade's. <br /><br />Thanks in advance:<br /><br />Bryan<br /><br />
 
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emperor_of_localgroup

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I was ecstatic looking first time at the moon craters last weekend through my Nexstar 8i. Now I cant wait to look at the mars this fall and other planets. <br /><br />I recommend Nexstar 8i because the motor control is very elegant, unlike the bulky weight hanging on other older telescopes. If you have more money , get the Nexstar 8i with GPS system. Although I haven't looked at the deep space objects wih 8i yet, but I think it has the potentials. Unless someone here has different opinion.<br /><br />Anyway, any one here knows how big the Mars will look like with an 8i (8") telescope? A golf ball size or bigger with a 4mm eyepiece? <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>
 
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petepan

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<font color="yellow">Anyway, any one here knows how big the Mars will look like with an 8i (8") telescope? A golf ball size or bigger with a 4mm eyepiece? <br /></font><br /><br />That depends on the focal length of the scope.<br /><br />EG: My 4.5" reflector has a focal length of 900mm<br /><br />Divide the focal length by the EP to get magnification: <br /><br />900mm/4mm = 225X mag<br />900mm/25mm = 36X mag<br /><br />So Mars would appear 225 times bigger using a 4mm EP or 36 times bigger using a 25mm EP. <br />A bigger scope only improves the light gathering ability.<br />Does that help?
 
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emperor_of_localgroup

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Yes, I forgot to mention the focal length. My 8i has a focal length of 2032mm (80 inch). That gives me a magnification, with a 4 mm eyepiece, of 508. And with a 25 mm eyepiece (which is easier to use) mag=81. <br /><br />Does this mean if a planet, with naked eye, looks like say 1mm wide, will appear as 508mm (50.8cm) wide? That's huge.<br /><br />I found locating an object and keeping in view is extremely difficult with a 4 mm eyepiece. Is there any tricks I can use? or it only needs more practice? <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>
 
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tfwthom

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What are you using a 4mm eyepiece for? Even on a night of perfect seeing you are way over the max the scope will support! You max out at 400x with an 8" scope. 50 to 75 power per inch is the rule, and an SCT never gets the 75 at high power, thats for refractors. <br /><br />BTW SCT's are the worst choice for lunar/planetary viewing. The best scopes for that are refractors, and top quality ones at that. If you can only afford Orion quality then just go to a star party and view through someones AP, Tak, or TV, and save your money. <div class="Discussion_UserSignature"> <font size="1" color="#3366ff">www.siriuslookers.org</font> </div>
 
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BReif

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The reviews of the Orion 80 mm ED and 100 mm ED Apo's have been extremely good. The gist of some of the reviews go somthing like this: While the Orion is not of the same quality of other premium Apochromats on the market, the quality is excellent, and for the price, it is a great value. Given these types of reviews, I was seriously comtemplating the Orion 100 mm ED. I have yet to see a negative review anywhere. Perhaps you have some information that I am unaware of... I am unable to convienently get to a star party, so I do not have an opportunity to look through the glass and compare. <br /><br />How about the SCT as a general purpose scope, understanding that something is sacrificed for planetary viewing, and DSO viewing. Is it adequate as a general purpose telescope?<br /><br />
 
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emperor_of_localgroup

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Thanks TFWThom for your advice. I'm still getting the hang of my Nexstar 8i. So much to learn and so little free time. <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>
 
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tfwthom

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If you ever look through an Orion refractor you will see the need for a v-block filter. Bright objects are violet.<br /><br />Quote from a review "If you are a picky viewer and dont like a hint of purple, shy away from this scope, mine shows a hint of purple. I personally don't mind and don't realize its even there on most objects anymore, and I actually like the purple tint on the brighter stars such as Sirius, which turns out to be a purple gem."<br /><br />OK maybe I'm picky, I don't like color in my scopes, that's why I own a Tak FS128 (G-11 mount) and a TeleVue 85 (Gilbraltar mount).<br /><br />I don't like the 8i either....because of the single arm. I feel that the single arm has got to put thrust on the bearings. Optics are good. Last I heard you can't upgrade the handcontrollers softwear, that may have changed.<br /><br />I like SCT's...I have an LX90 (owned since 2001) that gets a lot of use. The grab an go scope is the TV85 with the LX90 as the next move. Because the G11 mount takes the most setup it gets used (backyard) when the night is right or star parties or when I'm setting everything up for a weekend/special event<br /><br />Our club is doing public Mars viewing/outreach at the Sedona Library Oct 14th and Oct 30th so everything will be setup then. I'm even going to put the TV85 on an LXD55 GEM I have for the night.<br /> <div class="Discussion_UserSignature"> <font size="1" color="#3366ff">www.siriuslookers.org</font> </div>
 
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BReif

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With respect to the Celestron 8i, I do have some concerns about the reliability of the tracking motor, and the GOTO system. My Meade ETX broke 16 months after I bought it, and it is useless, and past the warranty. Can you comment on the single arm that the OTA is mounted on, and the motor and GOTO? Is this setup reliable? I don't want to repeat my Meade mistake.
 
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BReif

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What do you know about the Celestron CPC GPS 9.25 SCT? I am intrigued by what you said about the 9.25. <br /><br />BTW-Yes, I understand what you mean about the refractor samples out there. I have been posting on the Orion ED Yahoo site, and received a response from someone saying that they preferred their SCT to their refractor anytime.<br /><br />Perhaps my utimate goal would be to have both a 80 to 100 mm Apo and a large aperture, such as the 9.25, SCT. (would take some time to do though) What do you think...Thanks
 
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BReif

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The SCT that I am looking at, and leaning toward is the Celestron Series CPC 9.25 SCT, which will not be available on the market until mid to late October. There have been rave reviews, even a rave review at OPT, about the CPC 800 8" SCT. The 9.25 version should be spectacular. See Link: http://www.celestron.com/prod_pgs/tel/cpc_index.php#cpc914<br /><br />Given that this will not be available until just after Mars Oppostion, I may go ahead and get the APO first, then get the SCT in the spring. At least, that is my thinking at this point. Good strategy, or not?<br /><br />
 
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bonus

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Got you beat a little bit. I have a Meade and the tracking motor is through after only two slews. Meade owes me big. I have presently got an Orion Dobsonian XT 10. Putting bells and whistle on it and it is just getting better and better for me. I also enjoy the Orion 20 x 50 binoculars I have for quick observations of the moon. Would highly recommend we all stick it to Meade, and support Orion. There is quality and then there is junk. Meade sells junk friends.
 
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BReif

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I can never get through to Meade on the phone. I have been on hold for over an hour before I hung up. I have sent Meade a couple of letters expaining my situation with the tracking motors on the ETX 125, and never got a response, so I have given up on them. IMHO, the Meade ETX series is junk, and unreliable. Meade cutomer service is non-existant, and I wouldn't buy a Meade telescope again.
 
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bbrock

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I don't ever recall anyone speaking highly of Meade Telescopes. Orion is the act to follow, and I have always admired Celestron for high quality, high end equipment. Their C20 Observatory Grade Scope is my asperation. However, in all fairness, the Meade DSI and DSI Pro are class acts. My hat is off for these products only. <br /><br />Clear Skies<br />Bill
 
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jcdenton

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Meade is becoming a lot like the Microsoft of the telescope industry, especially after forcing the patent issue with their Auto-level North alignment, causing Celestron to pay over a $100 royalty on each scope with this feature (though Celestron is wisely abandoning this alignment procedure and switching over to their new SkyAlign algorithm). Meade has also become quite complacent over customer support, possible due to their very successful sales. While I don't like the company's ethics, I do admire some of their products, like the new RCX400 line of scopes. <div class="Discussion_UserSignature"> </div>
 
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BReif

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Well, I went a whole different direction than I had planned. I spent a great deal of time comparing telescope setups, and the advantages and disadvantages of refractors, reflectors, and SCT's. What I have decided on doing, and have in fact already done, is order the Orion XT10 Dobsonian. I did this because, looking past Mars opposition this fall, I would like to pursue my interest in DSO's, and this is one of the best scopes to do that with IMHO. It also didn't break my budget like a 9.25" SCT or a 4" Apo would have. I am sure that it will suffer some giving images of Mars and the planets, but it should be sufficent enough to please the eye on these objects. Down the road, an 8" or 9.25" SCT is still possible, but, rather than continue to suffer from telescope paralysis, I went with the 10" Dob. If you'de like, I can post to SDC with a report how how it does with Mars, etc.<br /><br />Thanks for your input.
 
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jcdenton

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You made a good choice, since the Orion dobs are very economical and user-friendly. As for viewing planets, big dobs are not bad at all, some people even prefer them to APOs. The image may not be as steady as in refractors, but you can boost the magnification much higher (granted the seeing conditions allow for it).<br /><br />And by all means, tell us how your observations go. <div class="Discussion_UserSignature"> </div>
 
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bbrock

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I have used the XT10 out to 600x. I have used it for viewing planets at 400x for many months before I baught the Atlas EQ mount to put it on. The XT10 will go well with planets at high power, but you are going to need good quality EP's. You will need to get used to viewing quick and pushing quick. But it is dooable. I did it for a long time. <br /><br />I know crazyeddie likes dob platforms, but I strongly suggest you look into the Atlas Mount --- when you get to that point. The XT10 can be fitted with 12" rings and mounted on the Orion Atlas EQ Mount. This is a substantial mount that requires 33 lbs of counterweight for the XT10. Orion is now coming out with an upgrade kit, available in late September to convert the Atlas EQ mount into a Go-To Mount. <br /><br />Start with the XT10, later augment with an German EQ mount { you now have two scope mounts with one scope }, then upgrade to a Go-To, Autogide and Computer Planitarium Control ( Starry Night Pro ). Spread the cost out over a few years and your wife will probably go along with it. <br /><br />For now, you need to get a good 2x Barlow and lazer collimator. If you are going to high power, you had better be well collimated. <br /><br />Clear Skies<br />Bill
 
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BReif

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I do have some eyepieces left from my ETX, the who Meade Eyepiece set actually. I am not certain how good these Meade eyepieces are, but I will try them out. They are 1.25" ones from 32mm to 4mm, all plossl, I beleive. The XT10 comes with 2 plossl eyepieces to start with. I would like to get 2 or 3 good eyepieces and a 2x Barlow. Maybe I already have them, maybe not. What would you recommend for eyepieces (brand and size eg. Televue 32mm)? <br /><br />Crazyeddie, the platform is interesting. BBrock, so is the German EQ. Right now, my budget is used up. I will have to wait a bit for a platform or an EQ mount. I'm in no hurry. I just want to do some observing...
 
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BReif

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Looks like I will probably be investing in the Celestron Ultimas, a 30mm or 35mm CU eyepiece to start with for the low power views of DSO's. How are the Sirius Plossls that come with the XT10?
 
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BReif

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FIRST LIGHT REPORT<br /><br />Well, I finally had an opportunity to get the new Orion XT10 out and use it in the backyard (which is heavily light polluted BTW), and the optical performance of the 10" Dob was fantastic.<br /><br />1st target was Jupiter, low on the horizon. Using the 25mm Plossl eyepiece, jupiter rersolved into a well defined disk, two atmospheric bands visible faintly, and four major moons visible as points (sharp points) of light. <br /><br />2nd target, Mizar and Alchor: Stars resolved into bright sharp points, and Mizar itself was easily split with the 25mm eyepiece. Star test on Alchor revealed a concentric circle, showing good collimation.<br /><br />3rd target, the Double Cluster beneath Casseopia: Resolved in the 25mm eyepiece into hundreds of sharp points of light.<br /><br />4th target: M31, was a faint fuzzy patch of light, somewhat drowned out by the light pollution near the horizon.<br /><br />I need a dark sky site for this XT10 Dob. It is great! Here's a photo taken with my cell phone camera of my new Dob...<br /><br />
 
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BReif

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FIRST DARK SKY REPORT<br /><br />I had the opportunity to take the new Orion XT10 out to a dark sky site on September 30. What I was able to observe through this XT10 was absolutely astounding. First, I trained the 10" reflector onto M31, the Andromeda Galaxy with a 32mm eyepiece, and WOW! It was very bright, had a bright core, and structure seemed to be visible in the spiral bands. Then, second, the Double Cluster. Again, WOW! I have never seen so many stars grouped together like that, there must have been thousands of them, I coudn't count. Then, The Ring Nebula. Now, I had never found this before, but with a 20mm EP, I found it right where the charts say it sould be, and then boosted the magnification by putting in my 10mm EP. It was a fairly bright ring, with a central star, very faint central star popping in and out of view continuiously. It was awesome, and it gave such a rush to see that central star, which is so hard to see. Then, after Mars was high enough, I pointed the XT10 at it with the 10mm EP. It resloved into a fairly sharp disk with some darker features on its surface. I couldn't pick out the polar cap because of the brightness of the image, but the dark features were easy to pick out after a few minutes at the EP. Then, I just watched Mars for about an hour until I realized it was the wee hours of the morning, packed up, and head home. What a great outing...
 
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