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Red dot eyefinders?? Hard to see through, other better choices?


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Hello and good day..  Had my first night of viewing with my brand new setup last night..  Baader 8mm-24mm zoom with 2.25 baader barlow and a 4.5 orion starblast mini-dob..   Jupiter was amazing.. can't wait to see it again..

Red dot finders.. What a pain after you get the scope anywhere over 60 degrees, and even below that still hard for this nearly 60 year old to find an angle to get to see through..

I tried holding a small mirror behind it..  not much luck..  

Is there a better way. I see a few different designs.. 90 degree viewer type.  small screen with arcs and viewing dots??

There has got to be a better way. Please advise. I appreciate it very much..  when I first was reading about these. I thought they actully shot a lazer beam up in the sky..  sure seems like that would actually work? maybe not.. 

one side question. is there a small flashlight made with a red filter so you can move around in the dark without using white light?   thanks again..

can't wait to look through my setup again tonight..  and can't wait till the right deal on an 8 or 10 dob comes along.. 

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Part of the problem is you don't see through them in the normal way. You "ignore" them and look at the stars, the RDF just happens to be in the way. Then the red dot they produce is projected back onto your eye, hopefully in conjunction with where the scope is pointed.

There are telrads that operate in a similar way but I think they have a right angle mirror in the path so you look into them as you do a scope diagonal. Less contortions by you.

You could stick a laser pointer on the scope and align that. Then you don't look down, into or through anything. Getting steadily quite popular. Push the laser on and aim the beam at the area of sky. There is a laser pointer in the US that has an On/Off switch, just cannot recall who makes it. May be a better option.

Edited by ronin
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I used to have the same finder and couldn't use it. I prefer the cross hair type it's much easier to see where the scope is pointing in relation to the sky.

Not sure about the flashlight, there probably is one. The power pack I use has a removable red cover on the torch end and that works fine.

Happy stargazing.

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 A 5mW laser pointer, in a dedicated scope mounting, correctly aligned, should give you good visual direction to your target. Right angle finder scopes could be looked at, but lacking in experience of small Dobsonian s, the unit could well be too large and affect the scopes movement, others who will know, will no doubt be able to comment on this.

As has already been pointed out, a good basic torch, covered with Red cellophane, or painted with Red nail varnish, will do the trick. If you visit Ebay you will often find a variety of  LED head torches, that are also popular. Try visiting your local outdoor shop, ours in the UK often have good quality Red / White, LED head torches on sale from time to time :)

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Finders are a personal thing, some get on well with optical finders, either straight through or 90 degree, some like a Telrad, others a basic red dot, or have both an optical finder and red dot.

My personal favourite is a basic red dot finder, used with a low power wide field eyepiece to locate objects, then if necessary switch to a higher power.  It's a matter of placing my eye in the right position. When pointing at a high elevation, that's not always so easy,  I use a thick rubber mat to kneel on, so I can look through the red dot finder.

Any finder takes a while to get used to, so best to give it time, rather than spending on a replacement, before you are sure you need to.

Regards, Ed.

Edited by NGC 1502
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Might I point out that 'shooting' a real laser beam into the night sky is a BAD IDEA! If the beam comes anywhere near the eyes of a pilot (civil, military or police) and you will be heading straight to jail - and not passing GO or any £200/$200!!!

Even if the beam is switched off every time an aircraft is detected by you, the back scatter from atmospheric refraction could still show your position to a trained eye from quite a distance and the 'bracelets' will soon be gracing your wrists.

I know that the pros use them, but they have special dispenastion, access to flight paths and times and even radar. You don't.

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I too was going to say laser pointers are a risky thing to be aiming at the sky day or night.  What's more, if you are pointing your scope near to the horizon or slewing then there's a chance you could hit a road and the drivers on it, someone's window, a person walking their dog, etc.  I'd say best to steer clear, don't take the chance with a laser pointer.

A 90 degrees corrected viewfinder should help with your contortionist problem, although you may find that you also want a red dot finder.  A Telrad is quite large and probably not suitable for a small dob.  May I recommend trying the scope on a platform or low table that you can walk around, so that you don't have to bend down quite so far for the red dot finder?  Have a chair to hand too, then you may just be able to lean forward on it for the viewfinder if it's a RDF or straight-through one.

Edited by jonathan
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It sounds like your neck and mine are in about the same condition, I have used a telrad , red dot finder on my Dob but it really hurts to get behind them at times. For me the only solution was a 90 deg finder so that you can sit and switch between finder and scope with the same neck angle , but be aware of the weight that you are adding to the top of the scope.

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The problem is that you will always need some kind of straight-through finder to get to rougly the right place in the sky.  I use a Rigel finder for this and then use a right-angle finderscope to get a more precise location.  This means i spend the minimum amount of time limbo dancing to look through the finder and spend most of my time in a comfortable position.

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thank you for the input..  sure would seem someone would be making little red flashlight covers for the astronomers in this world doesn't it?

As far as the lasers. Our laws in U.S. ca.. basically only restrict use of them within 15 miles of any airport.. and of course purposely trying to point them at a plane or for any person(s) eyes for instance..   So as far as using them for a quick point system, I agree maybe not the best system, but if one is careful it wouldn't be the end of the world. It always comes down to the idiots that use these tools in a harmful manner that ruins our freedoms.. More rules, more regs, more government, more laws, just because a certain element have to be idiots and want to do harm or antagonize others.. those people could disapear from the face of the earth and not be missed..

My main problem is getting down behind the finder.. when the scope is pointed nearly strait up it is impossible to get the eyes behind it..  But, talking about this just gave me an idea for a viewer.. It may not exist and if it doesn't it just may be a real good answer for this problem.. hmmm.. I am an inventor and actually have one of my inventions coming to market in the next few months.. so maybe I can get this idea together. if it works it would be awesome.   of course I can't say what it is right here and now.. lol.. 

thanks everyone..

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dumped my red dot pointer before even using it...clearly 'mickey mouse ' compared with the quality of the scope . buy the most expensive finder you can afford. I bought an 'orion' correct image right angle 9 by 50. lovely optics . it is like a miniture scope. I can see DSO in it and that so helps finding them in the scope....I can not speak highly enough of it ! and my scope is not an 'orion'...

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Hi,

I have used used a straight through optical finder, a "standard" RDF, A Rigel RDF reticule finder, and a corrected (right way round/right way up) 90 degree optical. The Rigel (despite its cheap plasticky outward appearance) is quite sturdy and is great to use. The surpising thuing to learn is that you can position it in various ways - even either end of the optical tube on the proviso that you can line it up - and there is quite a lot of adjustment.

The 90 degree 9x50 optical - I find really easy to use and certainly saves the neck! Some people find that looking through 90 degrees is somehow counter intuitive - as opposed to looking up trhe tube, but I find this is not so. As one person has said - finders are a personal preference.  

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I had the same problem - neck -with the RDF and even with the Telrad which was certainly an improvement.  So I opted for a 9x50 right-angle finderscope.  The only problem with this is in pointing at your actual target.  I have a GOTO and the 5 deg view of the finderscope helps me find objects which don't appear in the telescope eyepiece due to inaccurate finding.  With a non-guided dob you will still have to roughly sight the finderscope and this can sometimes be a little difficult.

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I've not used the 8x50 optical finder that came with my 200p skywatcher since I got my Rigel Quikfinder, which stands some way above the tube at most elevations. The Rigel gets me close and then I use a 2" 32mm skywatcher Panaview to pinpoint my target before swapping to higher magnification eyepieces.

Although it may be legal to point laser pointers at the sky in parts of the USA I know of cases in California and Ohio when people were imprisoned for pointing low power lasers at aircraft, likewise, in the Uk there have been cases. Not worth the risk in my view.

For a red torch I use a small Maglite whose front glass I've painted with a couple of costs of red nail varnish.

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For a red torch I use a small Maglite whose front glass I've painted with a couple of costs of red nail varnish.

 I've mentioned in other threads that LIDL are doing a torch set for a fiver which includes a head lamp with 2 white and a single red LED.

Also Morrisons filling stations are selling a small torch for under £2 which can give a white beam, red glowing shaft (steady or blinking) or both together. Batteries are included in both sets.

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