Red dot finder questions

[milanpicard]

Hi, all, long time no see!

I would have a red dot finder question, I know it's not an eyepiece, but I did not find a red dot finder subforum.

Soo, my old red dot finder just refuses to work anymore. It's one from a 5-inch Heritage dobsonian, and I've been using it for my 8-dob as well. I put some powerful magnets between the clamps that fixed it to the scope, and I just put it on the metal tube of the 8dob, it stuck quite well. Of course, I had to screw and unscrue the two little screws that tighten said clamps whenever I switched to the Heritage (used without the magnets) and the 8dob (used with the magnets), this might have shortened its lifespan too, I guess some contacts no longer make contact in there because of so many movements.

So, I saw that my local astro shop has two options: the Celestron Star Pointer Pro and the Baader Sky Surfer 3 (a bit more pricey).

My questions would be: 1. Do I see it well that both of them have the same type of clamps that can be attached to a 5dob Heritage, if I take them off their metallic mounts?
2. How could I mount a red dot finder on the tube of the 8dob Celestron without stuffing the magnets between the clampsa and thus risking to deteriorate the casing of the new finder as well? I do not want to bore holes into the tube, and I see that the mounts of both finders have some holes for screws which the 8dob tube just doesn't have. Any easy suggestions, pls?

[Lady Fraktor]

The Baader is much better quality and comes with various adapters.
You may figure out how to leave one on each telescope and just move the finder.

Have you ever considered a Telrad?

[Ylem]

There is also the Rigel; https://agenaastro.com/rigel-systems-quikfinder.html

I prefer the Telrad, but the Rigel has a smaller foot print which is good for smaller scopes.

[Richard]

Well the RDF have a limited life , but all the ones I have had worked fine after years of abuse , normally its just a battery replacement , they used to be cheap , but have gone expensive , I do a lot of scope refurbs in RSA and ordered like 20 many years ago , have used them all now and new now in RSA is too much
I only like them on GO TO scopes , on my manual scopes optical is much better

[pakarinen]

I found the circles on the SP Pro to be too bright for my light polluted skies. I had to mask the diode to get it to a reasonably useful brightness. YMMV.

[yobbo89]

i use a simular one to this,the all metal ones seem to hold collimation way better then plastic ones

https://www.siderealtrading.com.au/prod ... ting-base/

[Bigzmey]

Hi Milan, I have moved your topic to Other Accessories. This is the proper place to discuss finders.

Getting back on topic, I use white 3M removable mounting tape to attach red dot base to the scope tube. I would not trust it to hold RACI base, but for red dot it is quite secure and you can remove it later if needed.

My favorite type of red dot is the basic Celestron Star Pointer (not Pro). I have tried fancier styles but that basic red dot serves me the best.



Quite few other vendors offer (or used to offer) the same model. It typically comes with a few different style bases.

[milanpicard]

It took me a while to find my post

Thank you for all your kind replies. I think I will get the Baader, then. As I see, it has some kind of holder arm that fits into the clamp on the tube of the 8dob, the one that holds the finder scope. And the clamp that holds the finder on the holder arm can be fitted on the 5dob Heritage. Can any of you guys confirm this? Anyway, thank you for your suggestions.

As for the other suggestions, after 3500+ objects seen in the sky I still do not know what a telrad really is, it looked out of my very limited budget so I did not bother with finding out about it, and my local shop only sells the Celestron and the Baader, so not much of a choice. Anyway, a good Christmas present. Thank you for your help!

[Lady Fraktor]

@milanpicard
Omegon sells their version of the Telrad for about the price of the Baader.
Very easy to use and can be used on multiple telescopes.
https://www.astroshop.eu/red-dot-projec ... er/p,58247

[milanpicard]

@milanpicard
Omegon sells their version of the Telrad for about the price of the Baader.
Very easy to use and can be used on multiple telescopes.
https://www.astroshop.eu/red-dot-projec ... er/p,58247

Thank you, I watched a video about the telrad, do I understand correctly that the basic difference between a telrad and a red dot finder is that the red dot finder puts one red dot on the sky, and the telrad uses a bullseye for it?

[helicon]

Correct, Nice that you are back on the forum

[Lady Fraktor]

That is correct. The different sized circles also allow for easy star hopping.
There are also many sites online that have free finder charts for the Telrad.

[SkyHiker]

It says the Telrad is easy to use with multiple scopes. I think they mean you need to buy a base for each scope first and stick it on permanently, which probably nobody does.

After I used my base for an old Dob I found that if I cut a rubber band from an old bicycle tube (it lasts forever) and use that to clamp the baseless Telrad down, I can use the Telrad on any scope because its feet align with the tube so you don't even have to recalibrate it when you move it around from one scope to the next.

So, the Telrad is much bigger and clunkier than needed but the way I use it, it is actually a good thing.

BTW Drilling a hole in a Dob is not too traumatic. I've cut up a Z12 tube to make it collapsible, drilled holes all over for two kinds of trusses and it still works fine. So I would not be too afraid to drill a hole for a red dot finder.

[Richard]

100% drilling a hole in a tube is easy just make sure its always pointing down and use masking tape on both sides to stop any filings on the important parts

[yobbo89]

I use a wet cloth and dab to get any loose filings out of the tube, and then tip the tube so the mirror is facing towards the ground and give it a few small light low pressure burst of air aiming to the inner side of the tube to get debre out from the rear of the mirror.

[milanpicard]

Thanks, guys, for all the good advice. I will get the Baader red dot finder then, since that is what I have been using for starhopping. And I can mount this finder on both scopes with the accessories that come with it. I will just exchange it for the finder scope of the 8dob, singe I can find things much easier with the red dot finder. Merry Christmas to me!

[chris0959]

Hello all,

I have a new Celestron 6SE.

The finder scope cannot be adjusted 'down' enough to align with the target star. The red dot hovers about '1 inch' above the target, and I have to approximate this offset when trying to align the scope.

I see this identical issue on other forums, but no official solutions...just cardboard shims and zip ties.

Does anyone know if this is a known issue that has a solution?

Thanks very much,
--C

[Bigzmey]

Hello all,

I have a new Celestron 6SE.

The finder scope cannot be adjusted 'down' enough to align with the target star. The red dot hovers about '1 inch' above the target, and I have to approximate this offset when trying to align the scope.

I see this identical issue on other forums, but no official solutions...just cardboard shims and zip ties.

Does anyone know if this is a known issue that has a solution?

Thanks very much,
--C

Welcome to TSS Chris! Red dots typically have two knobs to align them to the scope. I had a similar problem however with a couple of scopes where the adjustment range was not wide enough to align. In those situations a piece of cardboard, tape or thin plastic under red dot foot did the trick.

[Lady Fraktor]

@chris0959
Unfortunately this has been a ongoing issue with these finders but it can happen with others as well.
I had a expensive Moonlite focuser that I needed to shim my 9x50 finder to aim it properly.