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Hi all,

Usual story, 8" Dob, straight-through finder, Jupiter very high, and bad back.

I was going to go for a RACI, but folk seem to be recommending Telrad/Rigel. Am I missing something?

If you have a Telrad or Rigel don't you still have to get behind it to see through it, which would involve the same contortions as using the straight-through finder? Or can the screens be seen from 90 degrees?

I like the idea of having the illuminated bullseye of the T or R, but I really need to go for the comfort of the RACI.

Can anyone advise please?

Cheers,

Neil.

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Both, the comfort and ease of a RACI (particularly when just locating Jupiter) combined with the alternative use of a reflex finder for star hopping, such as mentioned Telrad or Rigel. I have a Rigel Quickfinder on my 8" dob, which serves best for balance and a telrad with 4" riser on my 14" dob where balance is not so much of a concern. I like using both, but prefer the telrad combined with riser (2" or 4" available) for more comfortable viewing. 

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Mount the Telrad on one of the optional bases this is the 4", there's a 2" also......

DSC_0839.jpg

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Apologies guys, but I'm obviously not getting it. My thinking is that it doesn't matter how high I mount the Telrad, I am still going to have to get behind it to see through it, making it no different to contorting myself to look through a straight-through finder. Can Telrads be looked through at 90 degrees like a RACI?

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There is no 90 degree viewer for the telrad its a straight through. What the telrad does best is to get you into the target area very quickly and accurately this then allows you to use the RACI to star hop . Using my Telrad on my 200 P Dob I usually have to go down on one knee depending on the elevation of the scope, it's well worth the effort though. I reckon the Telrad has massively reduced the time it takes to find targets compared to just using a viewfinder.

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Apologies guys, but I'm obviously not getting it. My thinking is that it doesn't matter how high I mount the Telrad, I am still going to have to get behind it to see through it, making it no different to contorting myself to look through a straight-through finder. Can Telrads be looked through at 90 degrees like a RACI?

I agree that looking through the Telrad can be a little awkward, however one of the key points about them is that you keep both eyes open and the red circles appear projected against the wider sky background. It is then very easy to position your scope in the right area and use a RACI to refine it down more precisely.

You can actually get a mirror cover option for the Telrad which pushes the image through 90 degrees but I think it loses a lot of its appeal used this way.

http://www.firstlightoptics.com/finders/dew-shield-for-telrad-finder.html

5bff8f976a894cfa7cdf733ae7b049a9.jpg

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Thanks all, I have a clear understanding now, I'll be on to FLO today. Telrad first, then RACI. Or both, depending on how devious I can be hiding the finances from 'er indoors.

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I use the Quikfinder and RACI - yes the Quikfinder is awkward at or approaching straight up, but in combination both finders complement each other as has been said. I really appreciate using both as a pair.

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I seem to have made the right decision then, I've ordered the Tel on a 4" stand and the Raci.

Anyone care to post a pic to show where they have these mounted on their Dobs?

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There we go them Coastliner ask and you shall receive. This position works for me. Notice the automatic magnification calculator just below the RACI. It makes life very easy. Dioch

post-38329-0-80365100-1429215569_thumb.j

post-38329-0-01040400-1429215589_thumb.j

Edited by Sirius Starwatcher

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the key difference with a telrad or similar and a straight finder is that with the telrad (I at least) simply do a rough alignment with the nearest bright star (naked eye) which takes maybe a second or two. then sit down and switch to the RACI to zone in to the target which is often visible in the finder is  if skies are dark. I once tried the mirror on the telrad but hated it.

my star hopping geode  guide might help.

http://stargazerslounge.com/topic/197640-collimation-and-star-hopping/

(don't you just love predictive text and a lack of attention)

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I use the Quikfinder and RACI - yes the Quikfinder is awkward at or approaching straight up, but in combination both finders complement each other as has been said. I really appreciate using both as a pair.

the key difference with a telrad or similar and a straight finder is that with the telrad (I at least) simply do a rough alignment with the nearest bright star (naked eye) which takes maybe a second or two. then sit down and switch to the RACI to zone in to the target which is often visible in the finder is skies are dark. I once tried the mirror on the telrad but hated it.

my star hopping geode might help.

http://stargazerslounge.com/topic/197640-collimation-and-star-hopping/

The above posts set out the way I do it too. I use the Rigel because I wanted to keep the weight and footprint to a minimum at the top end of my dob but the principle is the same. I've had a couple of nights recently when I've managed to find getting on for 100 messier and NGC objects, most too faint be seen in the finder. With a good sky chart, it works and it's fun too :smiley:

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