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starhopping with a reflector

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#1 lamplight

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Posted 05 December 2012 - 05:04 PM

Hi

Finding that just locating my alignment stars is a backache. Have to geton the ground practically for zenith.. then if I can't find it in finderscope I'm finding that I can get wayyyy out of the area as coordinates aren't making sense to me buy moving left/right/up/down with the controller while looking sideways into the tube... so I easily end up in an entirely different constellation... so its back behind the tube... once I'm close and can workfrom thefinder view itsbusiness as usual. But its taking many trips front to back of scope to get close. It seems far less intuiative thanthe same process on my SCT. It occurred to me one of those green lasers might help a lot. I've only been out with thereflector 3 to 4 times... its very difficult the closer to zenith.. will iget better or moreused to this or is the laser common for larger reflectors? (Hope I described the issue ok, typing on this android tablet sucks, buti did get sky safari plus for it and its like everyone says,awesome!)

#2 panhard

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Posted 05 December 2012 - 07:07 PM

Is the scope something like this one? scope

#3 lamplight

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Posted 05 December 2012 - 07:11 PM

Hi

Yes, I same scope but on a heavier Orion eq mount.

#4 csrlice12

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Posted 05 December 2012 - 07:52 PM

That's a big, heavy windsock you got there. Maybe put some rotator rings on it. You're not gonna have an easy time with that one...

#5 lamplight

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Posted 05 December 2012 - 09:33 PM

Oh I'm finding! But...themountisHEAVY so its not as bad as on the supplied cg5. The problem I'm having would apply to a dob too ..Maybe just need more practice.. I've gotten pretty good siting down the scope with the sct and when I look in the finder I'm practically right where I need to be. With this I'm not sure what it is.. maybe its the walkfrom bak to front of scope.. too much time and I get disoriented dodging counterweights .. I'm looking forward to eitherbuilding/buy a dob base or buying a 12-14" dob in spring.

#6 panhard

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Posted 05 December 2012 - 09:42 PM

The problem I'm having would apply to a dob too .

With a dob there is no need to get down on your knees, except when viewing near the horizon. An adjustable viewing chair makes life even easier.

#7 lamplight

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Posted 05 December 2012 - 09:58 PM

Thanks, but I'm not explaining my problem well enough. I'm talking about sighting dwn the tube to get in the neighborhood of said object.. its more accurate if I'm looking down the full lenghtof tube . (Ground, or ok, in viewing chair). What happens is if I go back to finder scope an browse around, if I'm NOT finding what imooking for I find it far too easy to browse right into another constellation andnot know it. Maybe its just new scope issues and getting used toit,plus getting used to eqmounts etc all at once. I don't seem to have this issuewith sct but maybe its just easier with that type of scope and mount: only have to move my head a few inches rather than few STEPS. I was thinking... with a green laser as I've seen them described, I would not need totake that stroll to the back of the scope so much. Or maybe juat get better (shrug!)?

#8 Ed Wiley

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Posted 06 December 2012 - 12:35 AM

Hi Matt: Yes a green laser will help, but you have to be careful with it and they usually are not welcome at group sessions where folks are doing astrophotography (read just about any star party). If you get one, be careful, especially if there are airplanes in the air and people around you on the ground. Lasers must be used very carefully and only turned on when doing at initial move.

But there is another solution: a Telrad. They are zero power, you can use both eyes and you can mount it at the front of your tube. Its still a bit of a pain at zenith but certainly beat trying to site the tube itself.

Another solution:Do you have a right-angle finder? If yes, then you need a Telrad. If not, try using both eyes, one through the finder and the other scoping out the sky at zero power. Once you get used to it, it works.

Ed

#9 beatlejuice

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Posted 06 December 2012 - 12:46 AM

But there is another solution: a Telrad.



Plus a 4" Telrad riser and relax as you point to the right star.

Eric

#10 frito

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Posted 06 December 2012 - 12:54 AM

yeah i was going to say a telrad on a riser or a rigel quikfinder. mount either one as far forward as you can. at zenith anything except large scopes taller than you are always going to be a pain in the neck literally with zero mag finders or straight through's thats why i like the rigel/RACI combo i have on my XT8. rigel gets me in the area quickly, RACI narrows it down in comfort.

#11 Tony Flanders

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Posted 06 December 2012 - 05:31 AM

I'm talking about sighting dwn the tube to get in the neighborhood of said object.. its more accurate if I'm looking down the full lenghtof tube.


Okay, now I understand ... except that I don't understand why you're doing this.

Sighting down the tube is a useful fallback when all else fails, but it's inferior to just about every other technique known. A simple paper-towel roll taped to the front of the tube would be an improvement. An inexpensive red-dot finder would be a huge improvement. A red-circle finder would be better yet. And an old-fashioned finderscope works fine, too. Just keep both eyes open, and you will get your initial fix.

So exactly why are you using this caveman technique?

For that matter, what do you do on your SCT? Still sight down the tube?

#12 Jon Isaacs

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Posted 06 December 2012 - 06:35 AM

I've only been out with thereflector 3 to 4 times... its very difficult the closer to zenith.. will iget better or moreused to this or is the laser common for larger reflectors?



Matt:

As others have said, a Telrad is a big help in situations like this. (Note that the Telrad and the Rigel have the same height though it doesn't look that way.) A few questions:

- What finder are you using? With a straight-through finder, you can point the scope to the first guide star by keeping both your eyes open. What you see is the finder crosshairs superimposed on the starfield. Move the target star towards the crosshairs and suddenly it will appear in the finder scope and you are done.

- "Rotating rings" are a big help with a Newtonian on a Equatorial mount. The position of the eyepiece changes as you move about the sky. With standard rings, you have to loosen them and hopefully rotate the tube without losing your alignment. Rotating Rings allow you to just rotate the scope anytime you want. I consider them a necessity with a larger Newtonian on an EQ mount. Commercial rings are expensive but there are various solutions, the "Wilcox rings" are simple, add a third upper ring to keep the scope from slipping and loosen the others a bit.

I modified the rings on my 8 inch F/5 by adding a third ring, doing a bit of grinding and then replacing the felt with bondable Teflon. It worked well enough that I sold the ball bearing rings that I had.

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Jon

#13 jfaust75

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Posted 06 December 2012 - 10:21 AM

I suspect you would really like having a green laser mounted on your scope. Orion sells a bracket to mount it as well as a few other companies. once mounted and aligned you can use it either as a finder(no need to bend or contort yourself) or as a locater to see where you are currently looking in the sky.

as others have mentioned use it sparingly as you dont want to disturb others with it(airplanes helicopters......other observers etc) i use ours at star parties as well(in short bursts) but it is a very small amount of people and noone seems to mind(if you go to star parties you should ask if its ok before using).

in short.....great tool, but be careful

#14 lamplight

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Posted 06 December 2012 - 10:37 AM

this is the day i learn about rigels and telrads.. i didnt know there was another way! glad i asked ! i do have a raci like i said so once in the neighborhood im fine. ok i will check them out and do some reading.


yes and the tube rings thing looks like a very good idea by doing a 3rd ring, that makes sense.


i

#15 galexand

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Posted 06 December 2012 - 11:15 AM

Hey just to defend sighting down the tube... :lalalala:

I have a newt+EP that gets a 2 degree TFOV, and I find sighting down the tube to be perfectly usable. My telescope usage pattern emphasizes starhopping, so if I'm within a couple degrees of my target I can usually figure out where I'm going. Being sloppy when I'm lining up actually helps me learn the stellar neighborhood a little better. The telescope has a cheap red dot finder, but I don't use it much and when I do it is not really any better than sighting down the tube (parallax being my chief complaint).

It's on a dob so I can't actually get my head down to the low end of the tube, but it is just a little learning curve to develop the intuition when sighting from the middle of the tube.

I've got a couple other scopes with a 1.5 degree field of view...not so much experience with them yet. They're usable sighting down the tube, but I will say with the smaller view it is a little more challenging, and I find myself wishing they had a decent finder.

So...I know it's not for everyone but personally it fits my style just fine. :jump: Of course if I had any super long focal length instruments like an SCT, I would probably have different habits due to the small TFOV :)

Back to your regularly scheduled more-sensible commentary...

#16 panhard

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Posted 06 December 2012 - 11:25 AM

this is the day i learn about rigels and telrads.. i didnt know there was another way! glad i asked ! i do have a raci like i said so once in the neighborhood im fine. ok i will check them out and do some reading.


yes and the tube rings thing looks like a very good idea by doing a 3rd ring, that makes sense.


i

If I where you I would go with the Telrad and the 4" riser. Also do you align your present finder with the scope? Here is a photo of a Telrad. link

#17 csrlice12

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Posted 06 December 2012 - 11:26 AM

Ok, a dob/newt owner that hasn't sighted down the OTA, please raise your hand.....

anyone?

Didn't think so....

#18 star drop

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Posted 06 December 2012 - 11:31 AM

Hey just to defend sighting down the tube... :lalalala:

I have a newt+EP that gets a 2 degree TFOV, and I find sighting down the tube to be perfectly usable. My telescope usage pattern emphasizes starhopping, so if I'm within a couple degrees of my target I can usually figure out where I'm going. Being sloppy when I'm lining up actually helps me learn the stellar neighborhood a little better. The telescope has a cheap red dot finder, but I don't use it much and when I do it is not really any better than sighting down the tube (parallax being my chief complaint).

It's on a dob so I can't actually get my head down to the low end of the tube, but it is just a little learning curve to develop the intuition when sighting from the middle of the tube.

I've got a couple other scopes with a 1.5 degree field of view...not so much experience with them yet. They're usable sighting down the tube, but I will say with the smaller view it is a little more challenging, and I find myself wishing they had a decent finder.

So...I know it's not for everyone but personally it fits my style just fine. :jump: Of course if I had any super long focal length instruments like an SCT, I would probably have different habits due to the small TFOV :)

Back to your regularly scheduled more-sensible commentary...

Sighting along the tube framework is the way I have located objects for the last thirty years. It is doable with a 2/3 degree field of view.

#19 lamplight

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Posted 06 December 2012 - 11:32 AM

Herb,

absolutely i line it up! like i said in my first post once im that close in the neighborhood i have no problems.. when i started a couple months back my finding abilities multiplied as soon as i got a RACI finder. for my sct finder (stallarvue) has a generous 5.1 degree field and as ive read countless topics about rigels/telrads etc i never understoff whats so hard about navigating in a 5 degree field , with or without circles superimposed..i dont find it hard, especially if right side up correct image! on the reflector i have the orion 9x50 RACI . its getting within that narrow field in general which is challenging.. i was just reading the description of telrads ... the laser seems ideal but id rather not deal with one more powered gadget if possible.. ill read up on these and ask more ?'s

#20 lamplight

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Posted 06 December 2012 - 11:39 AM

My telescope usage pattern emphasizes starhopping, so if I'm within a couple degrees of my target I can usually figure out where I'm going. Being sloppy when I'm lining up actually helps me learn the stellar neighborhood a little better.


this occurred to me.. i have no problms using this method on my sct as thats just how i taught myself over the last few months.. the raci finder makes the difference having the charts match up. ive found some very faint objects in light pollution no problem this way.. ok i need to stop chatting and read up on these new options /techniques which sound better for the big newt in the air

#21 csrlice12

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Posted 06 December 2012 - 11:39 AM

Living in a major metro area, even our clubs dark site is on the airline landing pattern. Laser's are useless there, and the law doesn't like green lazers anywheres around the airport (and I don't blame them).

#22 Mark Costello

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Posted 06 December 2012 - 01:51 PM

When I last had a Dob, I used to find things by sighting down the tube or rocker box....

#23 lamplight

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Posted 06 December 2012 - 02:33 PM

for my sct i have a generous 60* field and as ive read countless


sorry this is totally wrong and probably noticed by many of you.. my stellarvue RACI finder has a 5.1* FOV. so..

thank you so much all of you.. so i read briefly about telrads and rigel.. i also noted how a couple people said keep both eyes open.. this is something i never tried and makes perfect sense to try. so what ive decided to try is this:

since the stellarvue finder is a larger FOV AND has a quick rotate eyepiece it makes far more sense to have this on the troublesome eq mounted beast. also it stands pretty high off the tube so that may help attewmpting the both eyes open technique.. i may have to add a rigel (havent founbd info on how to integrate the two yet but im sure i will, just havent looked hard yet).

so what they say about laying your tube horizontally is absolutely correct.. looks like i chipped my primary.. i didnt see that there was a small backing plate when loosening screws to add the different finder to this scope. so mad at myself. i knew this piece of advise too. its pretty small so hopefully wont affect aperture or focus much. i dont want to even think about removing it for inspection as i still have MAJOR collumation issues to address (loaded with info just need to do/try).

anyhow the projection of the sky thats viewable from different angles might be needed but we will see how this goes. now have the orion 9x50 RACI on the SCT, similar FOV should be fine.

#24 lamplight

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Posted 06 December 2012 - 02:34 PM

what i think is a scratch.. maybe if super lucky only a smudge? doubt it as it was a metal backing plat and dropped 5'. :( so stupid!

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#25 lamplight

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Posted 06 December 2012 - 02:36 PM

F60M2 attached:
def gonna get a third ring and setup for easier rotation while mounted. pretty sure i can do that without destroying the scope.

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