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Topics - Trendsetters Branch

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When I'm doing visual observing at a Star Party I like to do some wide field photography with a camera and lens. I recently got a Canon 200mm F2.8L lens, I tried it out at Okie-tex this year but the mount I currently use, (I think its an Orion Astroview, see picture) couldn't give round stars at 120 seconds at 200mm. I want to keep it as small and light as possible, but I don't want to mess with guiding. I know there are some camera tracker options but I wouldn't mine having a small mount that will work with a small scope as well. Thanks!


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I'm trying to image planets using my NexStar 8SE on an alt-az mount. After doing the SkyAlign the scope does a reasonable job of go-to i.e. the target appears in a 25mm eyepiece but is not quite centered. I then manually center the target in the eyepiece. Is this enough for tracking to work well, or will the initial non-centered go-to mean that the target will start to drift out of the FOV?

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Hello,

I just purchased a Zhumell 12" as my GRAB and GO scope. It was on craigslist and the price was SO low, that I couldn't pass it buy. Got it for just under $400! It is two pieces - the stand and tube. Each piece is under 40 lbs. I need to walk down 5 steps and then 15 feet into the driveway and I am observing.

However, the tube is AWKWARD to say the least. I was thinking about adding two handles, one to each side of the aluminum tube to carry it. Has anybody else out there done anything similar to this? The handles on my CPC1100 make maneuvering and carrying the fork/tube VERY easy and that weight 70 lbs. Does anybody know of an easy way to carry the tube minus the handle? If anyone has mounted handles, what handles would somebody recommend? Does anybody think that the aluminum tube can have handles added without ruining the structural integrity of the tube?

I went with the 12" Zhumell because of many trees and buildings are in my townhouse complex, so nearly everything I look at will be within 10 to 20 degrees from zenith. At 6'4", the eyepiece height of the 12" is much more comfortable for me than an 8 or 10".

Thanks for any help you can provide!

Mike

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Mainly posting this for curiosity and getting your thoughts. As I am asked for feedback on beginner GOTO scopes all the time i'd like to understand these two scopes below a little more. For the beginner quite a few people recommend a non goto dob or an alt az refractor, but given my better familiarity about cassegrain telescopes I am usually itching to recommend a cassegrain of some type and I think that is totally fine . Sure they have the disadvantage of them having a constrained slow f/ratio and you do have dew issues to figure out with the corrector being on the front, but overall i'm smitten with my Evolution C8, so when people at outreach events or new astronomers joining our area club ask me for a recommendation for something well under $1000, i'm usually itching to tell them to find a used C8, but lately i've wondered about 5" cassegrains (both MCT and SCT) for ease of portability as well as what one can truly see. The aperture is more than most decent refractors that can be had under $1000. They are great on planets which in many cases is what people like to see first and then dabble in more deep sky. And they come in packages with usable GOTO mounts with similar electronics as I have so I can help them through some of the initial newbie headaches to get them started.

One of my friends has a Levenhuk 105 Mak on a similar mount to the Orion Starseeker which is similar to the 127 SLT and it tracks very nicely. He uses it for EAA and some nice planetary stacked imaging. For the cost and size of that little scope i've been really very impressed. He even runs it on batteries quite frequently and gets decent run time.

I've seen a lot of recommendations for the 5SE which instead of a Mak-Cass it is a 5" Schmidt Cass, but what about the less expensive 127 SLT? Any love for the 127 SLT?

The aperture is the same for the two scopes below, but the focal length of the Mak 127 SLT is longer (1500 vs 1250 on the 5SE SCT) and the f/ratio is slower on the 127 SLT (f/12 on the 127 SLT vs f/10 on the 5SE). I've also heard that while you need to still collimate a Mak they are even less susceptible to losing collimation than comparable size SCT's. For the record my 8" SCT Evo purchased in Feb 2016 is still holding its factory collimation even after multiple tumble bumble trips in the car to the dark site, so this argument between holding collimation on Maks and Schmidts may be moot

To frame this a little better I'm interested mainly about the difference in real dark site or backyard experience between these two scopes-I really could care less about technical jargon or arc seconds of accuracy..we are talking 5" beginner scopes here-what's the real experience difference? I'm thinking of both beginners or as a grab and go for someone with a larger scope that would like something they could keep setup or "minimally" stored. For similar sky conditions and targets list including higher Mag objects like the Moon, Saturn, Jupiter, Lagoon and Orion Nebula, M13 and M3 and M11 what would the difference in what one actually sees? Is the 5SE really worth $250-270 more than the 127 SLT???

Both mounts use spur gear drives not worm gears, so i'm not sure that would make a difference. Both are alt/az Nexstar Electronics. Maybe the 5SE has a better tripod and stiffer mount, but on something like this would that really change the experience? Assume that both are setup on grass not concrete.

Head to Head Shootout!!!
Nexstar 127 SLT (Some suppliers have this as low as $439!)
http://www.celestron...rized-telescope

Nexstar 5SE (Usually sold for $699)
http://www.celestron...rized-telescope

Jon Thomas

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I am a high school Physics/Engineering teacher at a small PBL based high school in Evansville, IN. (http://www.evansvill.../real-world-now) In my teaching experience of 31 years, I have introduced students to Astronomy with borrowed telescopes or telescopes that I have picked up at yard sales. ( http://www.cloudynig...-i-ever-spent/) That first year I showed students sunspots, and the rings of Saturn; one of those original students became a science teacher and is now my principal!

I got away from Astronomy for several years but got the bug again last summer after finding that RV-6 last summer. I have started an Astronomy club at our high school and have recently acquired a Celestron 8SE from a donor. The kids and I are very excited, but the weather has been rotten for some time. However, with the solar eclipse coming in August of 2017 we have a unique opportunity as we are only 70 miles from Hopkinsville or Princeton, KY which will have a 2:40 second duration of the eclipse. We plan to take all of our students to experience this once in a lifetime event, but I want to them to see this in a number of different ways. This is where I need your help, and the members of Cloudy Nights have been more than helpful on several occasions in the past.

I want to purchase a dedicated solar scope (Lunt or Coronado?) , tripod, a video camera, and a solar filter for the 8SE, along with several Sunspotter Solar Scopes. What equipment would you recommend for this? Is there anything that I should be considering?

I have a number of goals with the Astronomy club’s future:
1) To get my students comfortable enough with the telescopes so they can do outreach programs at other schools and with adults.
2) To build an observatory so the school can have access to the telescope from their computer at home. Our school is in the Career and Tech Center and the students have the ability to design and build the observatory under one roof. (http://www.edlinesit..._Programs/SICTC)

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I'm trying to decide whether I want to load up my gear to go observe tonight... I just checked the Clear Sky Chart for my favorite observing location and its showing
-100% Clear
-Above Average Transparency
-Poor Seeing

My main targets will be globular clusters, nebulae, open clusters as well as maybe a galaxy or two

I knew that if observing planetary targets that seeing is highly important as well as for double stars, but with bad seeing will any of the other targets I mentioned be hindered?

Would you go out and observe?

Regards,
Jon

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ATM, Optics and DIY Forum / Catadioptric Gregorian Design Idea
« on: December 31, 2017, 05:55:17 AM »
I had an idea for a telescope design I had not seen before and wanted your opinions. The idea is to take a standard parabolic primary mirror and place a tiny flat at a 45 degree angle just past the focal point of the primary. This sends the diverging beam through an achromat or apochromat lens on the side of the tube to another flat and back through the lens so the beam is converging at the desired f ratio back to the other side of the tube to the focuser and eyepiece. Crude diagram attached.  The advantages would be extremely small secondary obstruction for any desired focal ratio. The disadvantage is the number of optical elements. Is something like this possible with off the shelf optics?
Thanks for looking.
Attached Files<li class="attachment">

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Beginners Forum / Looking for carbon and variable stars
« on: December 30, 2017, 09:18:51 AM »
Hi all, in looking through Cloudy Nights, I notice there are forums for observing almost every type of object save one, variable and carbon stars. Is there any info here on these as I can't really find anything. I'm mainly interested in carbon stars, but even beyond that, stars of various colors and types along the H-R spectrum. Note I'm just talking about visual observing here, not measuring or science or anything.

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Eyepieces Questions & Recommendations / first night with TV Nagler
« on: December 24, 2017, 02:23:18 PM »
So last night I took my 8" reflector out with my new 22mm TV Nagler to perform some lunar observing.  Having bought it blind rather than looked though a luxury EP I was dismissed.  I've spent time on and off with my range for several decades, but have only ever used the Plossls that came with the range.  the TV is immersive.  Just a completely different experience.

 For any other beginners out there contemplating updating to a quality eyepiece... DO IT!!!

 john

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