Red dot finders - advice please

mtfreestyler (Matt) · #1 12-03-2015, 04:18 PM

Hi Guys,

After going out and using my Newt I found it pretty difficult to know exactly where I was looking due to the magnification and not being very familiar with the night sky.

I thought that getting a red dot finder would help out so I could get it in the ball park then fine tune with my real finder scope and then finally look through the telescope.
Maybe even get rid of the finder scope all together.

I would just like to know if this is a good idea and if it has worked well in your experience.

If so, which red dot would you recommend?

Thanks, Matt

julianh72 (Julian) · #2 12-03-2015, 05:18 PM

I'm a big fan of red-dot finders - they are so handy to get a good fix on any naked eye target (but limited use for finding fainter targets, of course). I find them especially handy when your target is high in the sky, and you need to crook your head into some weird gymnastics to get to the eyepiece of a conventional finder-scope. (90-degree finder-scopes can be a big help here!) With a red-dot, it's much easier to see the alignment dot without needing to be perfectly aligned with the eyepiece of a conventional finder, and it's very easy to see which way you need to move, because you area aligning against the full sky-view.

I use a couple of Go-To mounts (1 x Celestron SLT, 1 x Celestron SE), so the red-dot finder is mainly used to get my 3 initial alignment stars, and then I can turn it off and use the Go-To function for everything else. I just use the really cheap basic red-dot finders that you can get for $30 or so on eBay - these don't have any ranging rings or a reticule that you find on a Telrad, which can be handy if you want to use the red-dot finder for star-hopping to find the fainter targets, but work perfectly well for aligning to visible targets.

sil (Steve) · #3 13-03-2015, 09:23 AM

I like the red dot finders on the budget Orion scopes - Orion EZ Finder II Reflex Sight. The StarPointer found on cheaper Celestron scopes are useless. I have a telrad and prefer it above all else, its handy having a ring at times instead of a dot which can cover up a target and make it difficult to know which direction to move the scope if its not in the eyepiece. Very easy on the eyes to use.

You might be able to repurpose your finderscope with a guiding cam in the future or find a red dot and finderscope together can work well for you at times. Plus you might need it if your red dot baterry goes flat. The only downside to red dot finders is they are silent and dont light up, you have to be looking through them properly to see the red dot, so once you turn your attention to the eyepiece you quickly forget to turn off the red dot finder, so its easy to leave them on and flatten the battery. Wish they beeped or automatically turned off.

SkyWatch (Dean) · #4 13-03-2015, 10:55 AM

I agree: red-dot finders are the easiest things to use and you don't usually need the "real" finder to fine tune. I can beat the go-to's nearly every time!
The cheapies work well, but I have found the Rigel QuikFinder to be one of the best. Does a similar job to the Telrad with a ring to sight on. It clicks on to its base in a second, and so it is very easy to pull off for storage; and because it sits up from the scope (more than a Telrad) it is easy to get your head behind it to sight. Matthew Lovell at http://www.telescopes-astronomy.com.au/ can source them, not sure where else in Oz.

- Dean

wavelandscott (Scott) · #5 13-03-2015, 02:09 PM

I am a big fan of the Telrad...I have one on each of my scopes. The "bullseye" is a great help and you can get star charts with matching rings to help you hunt down the faint fuzzier.

Sylvain (Jon) · #6 13-03-2015, 03:28 PM

I too like the Red Dot Finders, I recommend the metal ones with adjustable intensity - i found it useful depending on the whether you are observing from town or country - and various reticules - which can help in certain situations. About $70ish on eBay.

The great thing about Red Dot finders is that they do not magnify and as such you have a greater sense of where your telescope is pointing relative to the constellation you are looking towards and bright stars around. I have found this to be really a great improvement in pointing accuracy simply because it's a lot easier to position yourself "2/3 from that bright star" - this can be more difficult to achieve in a regular viewfinder when you cannot see the bright star in your field of view to begin with.

mtfreestyler (Matt) · #7 13-03-2015, 04:04 PM

Awesome help guys. It seems like everyone is agreeing that they are a big help.

I will look at both the Telrad and the Rigel one and decide which to get

Thanks for the advice

Renato1 (Renato) · #8 13-03-2015, 08:03 PM

You haven't said what type finderscope that you have. If it is a straight through one, you can improve your aiming accuracy by keeping both eyes opened. It's amazing how much easier it is to find objects than with only one eye.

Nonetheless, a red dot finder is still handy, especially for sparse areas of the sky. I have several Telrads and several small cheap so-called rifle ones. I use Telrads on bigger telescopes, the small ones on small telescopes.

The problem with Telrads is that you also need the cover for the glass, which stops it dewing over for an extra 10 minutes on bad nights, and then I use a 12V hairdryer on it. As I use the hairdryer on the smaller red dot finders.

I did once meet a chap with very good eyesight who claimed to have no problem finding galaxies with his Telrad alone, and had no use for his finderscope. Unfortunately, my eyesight wasn't as good as his.

You can hand hold one binocular tube behind a telrad, and get as good an image as in a finder.
Regards,
Renato

mtfreestyler (Matt) · #9 14-03-2015, 04:49 PM

I'm not sure what type it is but I got it with the SW 8" newt.

It flips the image and is magnified so I doubt it is a straight through one

Renato1 (Renato) · #10 14-03-2015, 06:14 PM

Quote:

Originally Posted by mtfreestyler

I'm not sure what type it is but I got it with the SW 8" newt.

It flips the image and is magnified so I doubt it is a straight through one

Sounds like you have a right angled finderscope. They are very handy to use, but with them I can't find anything without also using a red dot finder.
Regards,
Renato

Brycepj (Peter) · #11 17-03-2015, 08:34 PM

I had a red dog finder which came with my dob it was ok but really had issues trying to see through it properly. After discussions here I decided to get a telrad, I made my own due cover using black cover off a plastic folder and some velcrow dots and bingo no more dew.
I did also go and buy a Right angle correct view finder scope from bintell which is great for sky hopping. The telefax really works well.
That's what works for me anyway, once you align your scope telrad and finder scope it's a breeze.
Good luck