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Author Topic: tips on my rdf  (Read 1578 times)
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jamie
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« on: 13-Feb-2011 19:24:48 GMT »

i have a celestron 130 eq astromaster reflector scope and having problems aligning it to stars. it uses 2 red dots and 2 circles that you have to align with the object  you want to observe, during the day this is fine but at night its very hard to do against the dark sky.  one of the dots is to dim and its impossible to see the black circles against the black of the night sky .
i have a small refractor scope as well with a rdf which has 1 dot and that is great what ever you point at you can observe with ease.
ive looked at changing the rdf on the celestron but it looks unique to this scope, the mount does not look like anything else i've seen. i could get a single dot rdf for about £20 but i would have to drill a fixing on to the scope for a permanent fixture, surly that cant be good for the mirrors?
i,m i stuck with this rdf ? is there other rdf's that would fix to my scope with ease? or  has any one any tips on using  the rdf  i'm struggling with?
celestron is a big name in telescopes and can not see them putting a rubbish finder on one of there scopes so may be i'm doing something wrong.

i love my scope but this rdf makes me want to kick across the garden, only joking. cheers

 
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David Galvin
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« Reply #1 on: 13-Feb-2011 22:45:43 GMT »

Does the RDF have a brightness control? Usually they click on and then, as you turn the knob/switch, get brighter.
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jamie
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« Reply #2 on: 14-Feb-2011 22:37:56 GMT »

Hi dave how are you? no mate it doesn't have a brightness control, my other one has.This is just a red on/off switch. there are 2 lenses 1 at the front and 1 at the back about 2" apart from each other. each lens has a circle on it about the size of a 5p with a red dot in the middle, the idea is to align both circles and both dots with what ever you want to observe, this is all most impossible cause the circles are black and 1 of the dots is very dim. hopefully i've included a picture of the rdf. it looks permanently attached to the scope but can get it off but not seen another rdf to fit the mount what do you rec?
if i can make it wednesday i'll bring the scope with me for you to have a look at  cheers jamie.


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David Galvin
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« Reply #3 on: 14-Feb-2011 22:53:07 GMT »

I cant see the top of the image but it looks like there are 3 adjustment points (120 degs apart) that may allow collimation of one of the dots. Bring it along on Wednesday if you can. Perhaps we can suss it out.
« Last Edit: 16-Feb-2011 13:13:05 GMT by David Galvin » Logged
brendan martin
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« Reply #4 on: 16-Feb-2011 10:18:28 GMT »

Hi Jamie, as far as I am aware of a night you only need to align the two red dots you dont need to see the black circles,
I would check with yor retailer to see if there is a problem with one of the dots.
cheers
Brendan
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