Finder scope or not to finder scope? That is the question. :-)

[thercman (Greg)]

Hey guys! So I am getting ready to order the mirror for my 12.5" truss tube build and trying to decide whether or not to order a finder scope. I currently have a Telrad that I could use and that is considerably lighter than a finder but it is only going to get me close to deep sky objects. I am considering the Stellarvue 60 & 80mm finders. The added weight on the cage could mean adding counter weight to the rocker box. Do you guys think the Telread will get me close enough or will I need the extra magnification from a finder scope?

Cheers,
Greg

[glend (Glen)]

It would depend on your eyes. Some people swear by Telrads others can't use them. Personally I hate Telrads because I have bad eyesight without my glasses and given I have multfocals Telrads are impossible to look through with any sort of clear vision.

[N1 (Mirko)]

1x finders are great, and if adjusted well, will do the job 99% of the time I guess.

That said, I like the rich views of small telescopes, so looking through a decent finderscope, often seeing your deep sky target in plain view, is kind of neat too.

[raymo]

A Telrad will put an object into the field of view of a low power eyepiece, but that's not your problem.
How are you going to find and centre in your eyepiece objects that can't
be seen with the naked eye? Unless you plan to stick to very bright
targets, the light gathering power of a finder is essential. With the light gathering power of your 12.5" you will need at least a 50mm finder.
Nothing to stop you having a Telrad [or similar] as well.
raymo

[Renato1 (Renato)]

I use a 50mm correct image finder and a Telrad on my dob. That makes life very easy using my Herald-Bobroff Atlas. And I have met people with eagle eyes who said they didn't need a finder after getting a Telrad (no way I could do it)

If on a budget, you can always just use the Telrad and put one tube of a hand held binocular behind it. Awkward - but it does work.
Regards,
Renato

[Tinderboxsky (Steve)]

Greg, there is a Stellarview 80mm finder listed for sale by El_Draco and lurking near the end of Accesories for sale forum. If it is still for sale, it might help focus your decision.
Just as others have commented, it is my experience that a finderscope is essential when searching out very faint objects in areas of few stars above naked eye visibility.
Good luck with your build.
Steve

[thercman (Greg)]

Thanks for all the great responses everyone! It makes sense to use some type of magnification with this size aperture, I just wasn't sure how much was enough.

astro744,

Thanks for the in depth response it helped a lot...


Do you guys have any other recommendations? Maybe a small 60mm refracter?

[doppler (Rick)]

I have a 10" newt on an eq mount (not goto) . 90% of the time I can find what I am looking for with the 50mm finderscope, but it is so much easier and faster when I use my 120mm f5 guide scope. If you are thinking refractor get a short focal length, you need wide field views.

[cometcatcher (Kevin)]

Red dot does me fine.

[garin (Garin)]

Are you intending on installing dsc's/argonavis ?
I have installed the dovetail for my 9x50 finder scope on my 18" but in truth I don't use (yes Peter Read you were right) it as the telrad makes easy enough to centre alignment stars in the eyepiece for my initial alignment and from then on the argonavis can get to where I want to go.
But as in my case you can fit the dovetail but that doesn't mean you have to use it all the time.

Cheers
Garin

[Meru (Michael)]

Perhaps a 50mm finder + 1mw green laser module would be a good hybrid? Very nice being able to see a beam going to exactly where you are looking. Cheaper and ligher than a Telrad too I could 3D print a holder for the module if you liked food for thought

[thercman (Greg)]

That's cool that you can do 3D printing... I have been looking at lasers too. With all my hobbies something like could come in handy...

Currently I believe the 60mm Stellarvue would compliment the scope well. However I might just wait until I get the mirror mounted and do some viewing using just the Telrad since I have it already.

[glend (Glen)]

Originally Posted by Meru

Perhaps a 50mm finder + 1mw green laser module would be a good hybrid? Very nice being able to see a beam going to exactly where you are looking. Cheaper and ligher than a Telrad too I could 3D print a holder for the module if you liked food for thought

Lasers are a curse to imagers. I have had a number of good exposures ruined by people waving around lasers while they discuss the sky. If you get a laser then keep away from any group/star party gathering where people might be imaging.

[Meru (Michael)]

Greg,
Definitely useful being able to print, if you need any help with that or laser modules let me know

Glen,
Yes as an imager I've had the same experience. OP is about general finder options, presumably for a home setup. Down to the operator to make sure they use their set up correctly, just like flashing bright white LEDs around and leaving headlights on at starparties etc

[andyc (Andy)]

I've used both, including more than one variety of red dot finder and Telrad. Didn't enjoy the Telrad too much or the other dot finders - if you're star-hopping to fainter visual targets it really helps to be able to see the fainter stars to keep your bearings, even a 30mm finder will do, though I have gone up to a 50mm finder. This is especially true if you have any light pollution and your naked-eye stars are at all restricted, then locating an object with a Telrad can be pretty tough. With the 50mm finder (on a 16" Dob) I can see all the stars on Uranometria, and so hop to all sorts of targets and confirm where I am in relation to reference stars. I wouldn't have though you'd need a larger finder .

But each to their own, it's clear that lots of people love the 1x finders too!

[GrahamL]

Have a tak 6x30 mounted on my telrad,,and its still a great combo I find .
Small , light and able to dust off most fields you might want to get a finders eye view ,,, my 50mm really didn't offer much more in regard in that I would still switch to a low power eyepiece at a similar point.