Which Red Dot Finder?

[bendiddley]

Hi all. Can anyone give me their thoughts on which one of these red dot finders I should go for? I don't really know how well any of these perform compared to each other, so any thoughts are welcome. Also I want to attach it with adhesive rather than drilling holes, so this may affect which one is suitable. You may say none of these are any good and if so do you recommend any others? Just to add I already have an RACI finder which is very useful and want the RDF to complement it rather than replace it.

http://www.firstlightoptics.com/finders/baader-30mm-sky-surfer-iii.html

http://www.ebay.co.uk/itm/Telescope-Red-Dot-Finder-Multi-reticle-W-O-compatible-/380435290786?pt=UK_Telescope_Eyepieces&hash=item5893b5daa2

http://www.scopesnskies.com/prod/antares/red-dot/finder.html

[Spec-Chum]

I find my telrad invaluable, and it comes with adhesive on the base, so no drilling needed.

[Stephen]

Telrad

[John]

2 of the 3 you link to will need to either replace the current finder or need drilling to mount a new foot. The E.Bay one is for a different scope / focuser so won't be easy to attach at all I'm afraid.

For your scope I think the best options are either a Telrad or a Rigel Quikfinder. Both are better RDF's than the single dot type and both are designed to be attached with self-adhesive bases so no drilling.

[Darkstar_1]

+1 For the Telrad, i have used an RDF and the telrad is miles better.

[NGC 1502]

Another vote here for the Telrad. The problem with many RDFs ( I have a Multi Reticle one ) is they don't go dim enough despite having a brightness control. I fixed mine with red nail varnish over the LED, took several layers to get it right. That particular unit has to be partially dismantled to get at the LED.

The Telrad does go dim enough and can be attached with the sticky strips. The Rigel Quickfinder has the same attributes.

Regards, Ed.

[bendiddley]

Ok. So Telrad's or Rigels are getting the votes. I had heard telrads were mean't to be pretty good, but was a bit put off by it having the extra rings and thought they might be distracting, although I do understand why they are there. Does any one use telrads for simply getting the scope where you want it to be so you can move to the RACI, if this makes sense, rather than for the star hopping process using the rings? Or would the rigel be better suited for this?

[camoscato]

Another vote for Telrad. Piece of cake to set up, and makes a world of difference when aiming the telescope.

[JamesM]

Totally agree with Ed above about the dimmability (...I'm starting to make up words ) of many finders and would also recommend the Telrad or the Rigel Quikfinder which is a lot smaller. The Telrad can be attached to the scope via a slim housing and additional ones can be purchased (£7.50) should you have more than one scope and there is also a further choice of two other bases of different heights (2" & 4" high) which can be viewed here.

James

[paul schofield]

+ 1 For the Telrad, or a Rigel Quikfinder. with the Quikfinder you also get 2 bases so can be used on 2 scopes.

[NGC 1502]

Ok. So Telrad's or Rigels are getting the votes. I had heard telrads were mean't to be pretty good, but was a bit put off by it having the extra rings and thought they might be distracting, although I do understand why they are there. Does any one use telrads for simply getting the scope where you want it to be so you can move to the RACI, if this makes sense, rather than for the star hopping process using the rings? Or would the rigel be better suited for this?

A Telrad or Rigel work well in combination with an optical finder. Many DSOs are visible in an optical finder even under light polluted skies, M27, 29, 13, 92, 42, etc etc.

It's a bit clumsy looking on a modest scope to have all that hardware attached, but for me a scope has to work well first, looking pretty is very much less important

Regards, Ed.

[bendiddley]

Totally agree with Ed above about the dimmability (...I'm starting to make up words ) of many finders and would also recommend the Telrad or the Rigel Quikfinder which is a lot smaller. The Telrad can be attached to the scope via a slim housing and additional ones can be purchased (£7.50) should you have more than one scope and there is also a further choice of two other bases of different heights (2" & 4" high) which can be viewed here.

James

what are the advantages of the 2" or 4" and can these be stuck on as well?

[John]

..... Does any one use telrads for simply getting the scope where you want it to be so you can move to the RACI, if this makes sense, rather than for the star hopping process using the rings? Or would the rigel be better suited for this?.....

I've used mine just like that. Much of the time the Telrad / Quikfinder is enough to get an object in the field of view of a low powered eyepiece but sometimes an optical finder is needed to make the final adjustments before moving to the scope eyepiece. The Telrad has 3 rings, 4, 2 and half a true degree and the Rigel just the two, the 4 and the half degree ones. The half degree circle is pretty precise when you think that a low power eyepiece in the scope can easily show 1 degree of sky. The ability to really dim the reticules (rings) is important - most RDF's I've used are too bright even on their lowest setting.

Edit: I've not found the need to use a riser with a Telrad but some others do like these. The Rigel's view port is a bit higher off the scope tube than a Telrad's but the eye positioning is a little bit more critical with a Rigel.

[bendiddley]

I've used mine just like that. Much of the time the Telrad / Quikfinder is enough to get an object in the field of view of a low powered eyepiece but sometimes an optical finder is needed to make the final adjustments before moving to the scope eyepiece. The Telrad has 3 rings, 4, 2 and half a true degree and the Rigel just the two, the 4 and the half degree ones. The half degree circle is pretty precise when you think that a low power eyepiece in the scope can easily show 1 degree of sky. The ability to really dim the reticules (rings) is important - most RDF's I've used are too bright even on their lowest setting.

Edit: I've not found the need to use a riser with a Telrad but some others do like these. The Rigel's view port is a bit higher off the scope tube than a Telrad's but the eye positioning is a little bit more critical with a Rigel.

That's good to know. OK with the telrad what about the positioning on the scope? I don't really want to move the optical finder and the only place is either between that and the focuser or to the right of the optical finder which is a bit of a stretch. In the former though I would need to move the telrad down as there isn't a gap big enough otherwise, is this OK to do?

[John]

That's good to know. OK with the telrad what about the positioning on the scope? I don't really want to move the optical finder and the only place is either between that and the focuser or to the right of the optical finder which is a bit of a stretch. In the former though I would need to move the telrad down as there isn't a gap big enough otherwise, is this OK to do?

This thread will help:

[Stephen]

That's good to know. OK with the telrad what about the positioning on the scope? I don't really want to move the optical finder and the only place is either between that and the focuser or to the right of the optical finder which is a bit of a stretch. In the former though I would need to move the telrad down as there isn't a gap big enough otherwise, is this OK to do?

You can place it 1/4 the way round the tube (so in the same position but on the other side of the tube) or right next to the finder (it's not that much a stretch honest!)

Or do as I did and ditch the finder all together

[John]

Ooops ! - just realised that the pics don't seem to show in that thread. Here is one which should help (not my scope I should say):

[Tinker1947]

As said a Telrad plus Stellarium, Telrad maps both these items are free, ditch the finder its unwanted weight........

[bendiddley]

Ooops ! - just realised that the pics don't seem to show in that thread. Here is one which should help (not my scope I should say):

thought it might be ok to put it there. is that on a riser plate on that pic?

[John]

thought it might be ok to put it there. is that on a riser plate on that pic?

No, thats just the standard mounting plate supplied with the finder. No riser in that pic.

[bendiddley]

As said a Telrad plus Stellarium, Telrad maps both these items are free, ditch the finder its unwanted weight........

those telrad maps look great, i've been printing similar ones I made myself using stellarium and photoshop for individual objects but this could save me a lot of time. think the telrad is the answer, not sure about ditching the optical just yet though as I find the reverse image at the eyepiece a little hard to use at the mo, using my RACI finder helps with that as it minimises the hunting at the EP.

[bendiddley]

OK . I've just been to FLO and they have a couple of options I'm not sure about when you go to buy the telrad. First is the additional base plate (what's this for?) and secondly is a dew shield (do I need this)?

[Stephen]

Base plate : allows you to use it on more than one scope (Telrad fits on base plate which is stuck to OTA. You get one already with the Telrad.)

Dew shield : prevents dew forming on the Telrad screen (Never needed one myself, but if it's particulary dew-ey where you are, you may want to consider it.)

[bendiddley]

Going onto the rigel... I notice that the rigel has one less ring than the telrad and I wonder if this is helpful because you can see more sky ie. less rings getting in the way? I am not totally sold on using the telrad for star hopping (for me that's the RACI) but more as a way of aiming the scope in the right direction and using the RACI to fine-tune, so wonder if the Rigel would be more suited to this?

[John]

This is a link to a review of a number of RDF type finders including the Telrad and the Rigel Quikfinder. It shows what the reticules of the different types look like:

http://www.cloudynights.com/documents/9finders.pdf

I own a number of these but the Telrad and Rigel are my favourites. The Telrad is a more robust item than the Rigel but takes up more room on the scope tube.

When using them, I find the trick is too focus on infinity and look past, rather than through, the window of the finder, if that makes sense. That way the reticules appear projected on the starry backdrop. I find using both eyes open works for me.