Some Q's about Telrad Finder.

[csb (Craig)]

I'm thinking about getting a Telrad Finder for my 120mm refractor. I have some questions:

1) Is the double-sided tape that comes with the telrad a good method for affixing to the scope?
2) Where along the tube is the Telrad fixed?
3) Once aligned, is the alignment stable (ie doesn't usually need realignment)?
4) Can I use the aligned Telrad to then align the finderscope? I have a GoTo mount.
5) Is the Telrad better than a Red Dot finder?

[tnbk00 (Daniel)]

Originally Posted by csb

I'm thinking about getting a Telrad Finder for my 120mm refractor. I have some questions:

1) Is the double-sided tape that comes with the telrad a good method for affixing to the scope?
I have had no issues with the tape.

2) Where along the tube is the Telrad fixed?
Where ever it fits i guess. I cut a section of the telrad base out to fit between the focuser, and the finder dovetail base.

3) Once aligned, is the alignment stable (ie doesn't usually need realignment)?
It seems pretty good, I check the alignment every now and then and it seems to stay reasonably stable, even taking the telrad on and off.

4) Can I use the aligned Telrad to then align the finderscope? I have a GoTo mount.
I use the telrad to get in the general area. I guess you could use it to do so, but personally I would still use a reasonable powered ep to line up the finder.

5) Is the Telrad better than a Red Dot finder?

I guess this is a matter of personal opinion, but having owned both i prefer the telrad. I find with the red dot as it covers whatever you are trying to center it can be a bit of a pain, where the telrad has no center dot, and you can clearly see what you are trying to center.

before flaming me, this is all based on my opinions

Daniel

[programmer]

Originally Posted by csb

I'm thinking about getting a Telrad Finder for my 120mm refractor. I have some questions:

1) Is the double-sided tape that comes with the telrad a good method for affixing to the scope?

For me, yes

2) Where along the tube is the Telrad fixed?

I have a dob, so up the top of the tube

3) Once aligned, is the alignment stable (ie doesn't usually need realignment)?

Pretty stable if not bumped. Very easy to tweak alignment though.

4) Can I use the aligned Telrad to then align the finderscope? I have a
GoTo mount.

Not sure how you'd do this.

5) Is the Telrad better than a Red Dot finder?

Don't know, but I like(d) the concentric circles. I used past tense because I doubt I'll need it again as I have an Argo Navis. Not sure why you'd need it with a goto? It's also not that useful in suburban skies IMO.

I might sell mine as I doubt I'll use it again.

[csb (Craig)]

How I think I can use the Telrad to align the finderscope:

Use the Telrad to find bright star
Put star in center of FOV of telescope and track with GoTo
Align the finderscope.

Does this sound correct?

This will replace having to (re)align finderscope from balcony and then moving scope to ground level (I live on the side of a gully with views over an airport).

[programmer]

Originally Posted by csb

How I think I can use the Telrad to align the finderscope:

Use the Telrad to find bright star
Put star in center of FOV of telescope and track with GoTo
Align the finderscope.

Does this sound correct?

This will replace having to (re)align finderscope from balcony (I live on side of a gully with views) and then moving scope to ground level.

Sounds good to me. I've never had tracking. As long as the Telrad isn't too far out to begin with. And as tweaking only takes a few seconds, goto isn't really gaining you that much.. Unless I'm missing something. As I said, I've never had tracking.

[Geoff45 (Geoff)]

For a small scope like a refractor a red dot finder will probably look neater and work just as well as a telrad. On my RDF (William Optics) I can change the display, so that you can get a circle in which you can centre the star if you don't like the red dot covering the star.
Geoff

[madtuna (Steve)]

I find the Telrad Ideal for manually tracking the ISS with my SCT.

Have never had probs with the double sided tape and when packing up for the night removing the Telrad is easier than removing the finder scope.

Aligning is a lot easier too, though the Telrad not being magnified probably wont be as pin point acurate as a finder scope

[csb (Craig)]

Hi Steve

So when you reattach the Telrad, is it still aligned?

I like the idea of the tape as I don't have a place to mount and I will keep the finderscope in it's original spot.

Hmm, I didn't know that Red DotFinders can have circle also, opens the choice a bit. Except attachment type is important - tape is simple.

[madtuna (Steve)]

Originally Posted by csb

Hi Steve

So when you reattach the Telrad, is it still aligned?

I like the idea of the tape as I don't have a place to mount and I will keep the finderscope in it's original spot.

Hmm, I didn't know that Red DotFinders can have circle also, opens the choice a bit. Except attachment type is important - tape is simple.

9 times out of 10 yes.
when not you just adjust the two base knobs and tweek it back into allignment.

On my 140 refractor I much prefer the straight though finder but find the telrad best on my sct

[Rodstar (Rod)]

My Telrad is perfectly aligned pretty much every time that I take it off and put it back on. If it needs some tweaking, this is so simple with the little screws at the back.

[JimmyH155]

I have had same Telrad on SCT for 14 years. The double sided tape is still there, perfect and I have only got through 2 batteries
One of the best things I like about it is how easy it is to turn the brightness down (or up in the early evening) It's great
Yes, easy to take off at end of session and locates back in same place next time with just those 2 screws

[taminga16 (Greg)]

Craig,
The concentric circles of the Telrad are scaled at 0.5, 2.0 and 4 degress
providing the perfect tool for star hopping, and their brightness is adjustable.
The only concern that you may have is that the Telrad is quiet bulky.

Regards,

Greg.

[csb (Craig)]

Thanks everyone for your replies.

I had read about the 3 circles and that some star charts use them also.

Steve (madtuna) why do you find a difference between the red dot Vs telrad on your scopes?

I have a 120mm x 1000 refractor.

I'm leaning towards the telrad.