Jump to content

SkySurveyBanner.jpg.21855908fce40597655603b6c9af720d.jpg

What finder arrangement do you use with dobs


Recommended Posts

Hi all.

I’ve just realised I was looking through my Telrad the wrong way. No wonder I couldn’t get on with it 😂 I also realise now I ca adjust the position of the crosshair and suddenly it all makes sense. Only problem is I sold it with my old scope that is being picked up on Saturday 😂 nevermind. 

Just another couple of questions. I’m hearing a lot about a RACI Finder but what does it stand for? It seems some are illuminated and some are not but they are all right angled. The Telrad isn’t right angled so it sounds easier to just it with my straight through finder? Just wondering what people do. 

  • Haha 2
Link to comment
Share on other sites

RACI (Right Angle Correct Image) means the image is the right way up. There are also RA (Right Angle) finder where the image is not the right way up. Straight through finders also aren’t the right way up.

You can get this for your Telrad.

https://www.365astronomy.com/Telrad-Dew-Shield-Plus-Dew-Shield-for-Telrad-with-Mirror-for-Right-Angled-Viewing.html

Edited by johninderby
Link to comment
Share on other sites

2 minutes ago, johninderby said:

RACI (Right Angle Correct Image) means the image is the right way up. There are also RA (Right Angle) finder where the image is not the right way up. Straight through finders also aren’t the right way up.

Is a Telrad the right way up? When used with a typical dob? 

Edited by MSammon
Link to comment
Share on other sites

Should this thread actually be titled "What finder arrangement do you use with your dobs ?" ?

I use a RACI optical finder alongside a Rigel Quickfinder which is similar in function to the Telrad. Both show the same view my eyes see and the same as my star charts give.

When I view through the dob the view is inverted and E & W reversed but I find that I can cope with that provided that the view though the main scope is pretty exactly aligned with what the RACI finder is showing.

Others might prefer finders to show the same view as their scope though. I guess you have to find what works for you ?

 

  • Like 1
Link to comment
Share on other sites

11 minutes ago, John said:

Should this thread actually be titled "What finder arrangement do you use with your dobs ?" ?

I use a RACI optical finder alongside a Rigel Quickfinder which is similar in function to the Telrad. Both show the same view my eyes see and the same as my star charts give.

When I view through the dob the view is inverted and E & W reversed but I find that I can cope with that provided that the view though the main scope is pretty exactly aligned with what the RACI finder is showing.

Others might prefer finders to show the same view as their scope though. I guess you have to find what works for you ?

 

Yes sorry I meant finder. I’ll have to work out if I prefer the main finder and Telrad matching or the main finder and the view through the focuser. Just had a play about tonight and I quite like the Telrad and the finder scope matching. 

  • Like 1
Link to comment
Share on other sites

I've only ever used a Telrad with every scope except my Mak which is small. I have no idea why magnified finders even exist, someone figured they'd  have a good laugh by inventing a finder which flips the view and magnifies it, especially with a Dob, a Telrad is the god of finders. In my basement there is a box with finders I have taken off scopes over the years, they do make nice doorstops lol.

Edited by Sunshine
  • Like 1
Link to comment
Share on other sites

Telrads have their uses in finding things where you don’t need to be spot on but pretty useless when it comes to zeroing in on a small target.  Telrad gets you in the general area then switch to RACI finder. That’s why you see so many scopes with both fitted. 👍🏻

  • Like 4
Link to comment
Share on other sites

2 hours ago, MSammon said:

Hi all.

I’ve just realised I was looking through my Telrad the wrong way. No wonder I couldn’t get on with it 😂 I also realise now I ca adjust the position of the crosshair and suddenly it all makes sense. Only problem is I sold it with my old scope that is being picked up on Saturday 😂 nevermind. 

Just another couple of questions. I’m hearing a lot about a RACI Finder but what does it stand for? It seems some are illuminated and some are not but they are all right angled. The Telrad isn’t right angled so it sounds easier to just it with my straight through finder? Just wondering what people do. 

 

With my 10" Flex Dob, I use right angle 9 X 50 finderscope

Easy to use, and no laying on ground, with scope pointed higher altitudes, viewing DSO overhead

When day light, pick an object in distance, and align cross hairs finderscope, with what viewing through the eyepiece

The attached pic taken at recent public viewing night with my club 

John

 

Skywatcher 10 inch Dobson.jpg

  • Like 1
Link to comment
Share on other sites

If you live under dark skies, a Telrad might be the only finder you need.

Otherwise, a magnifying finder can make a difference. Personally, I do like straight through finders, and I have moved to Telrad plus RACI only very recently. Yes, this combo is a bit easier to use.

The way I do is: point with the Telrad, and then star hopping with Tablet and RACI finder. Dead easy! :)

  • Like 1
Link to comment
Share on other sites

I use RACI and Telrad. It is important to think about the positioning of the two units before fitting them. I think that you want the RACI situated so that you can use it from the same position as you look through the focuser and switch from one to the other easily. Unless you have a very large scope this means putting the Telrad on the far side of the RACI so that it doesn't get in the way. 

  • Like 1
Link to comment
Share on other sites

57 minutes ago, Ricochet said:

I use RACI and Telrad. It is important to think about the positioning of the two units before fitting them. I think that you want the RACI situated so that you can use it from the same position as you look through the focuser and switch from one to the other easily. Unless you have a very large scope this means putting the Telrad on the far side of the RACI so that it doesn't get in the way. 

Thats good advice and the approach that I use. I have managed to squeeze my Rigel Quickfinder inbetween the RACI and the focuser but a Telrad might not fit in there. Once you get used to where things are in the dark it works well and you don't really need to think much as you switch between these things.

 

oo12dob02.JPG

  • Like 1
Link to comment
Share on other sites

I find a Telrad essential for getting the target into the RACI’s field of view. You can do your fine adjustment / star hops from there. Some folks can aim a scope well enough, but I struggle.

Paul

  • Like 1
Link to comment
Share on other sites

48 minutes ago, Paul73 said:

I find a Telrad essential for getting the target into the RACI’s field of view. You can do your fine adjustment / star hops from there. Some folks can aim a scope well enough, but I struggle.

Paul

That's exactly what I was finding the other night with the 8". It's quite hard eyeballing the scope close enough to the target to get it it in the RACI fov as you say. I dug out a 3 in 1 finder adaptor and now have an RDF alongside my 10x60 RACI, works very well.

20190712_193403.jpg

  • Like 1
Link to comment
Share on other sites

39 minutes ago, Alan White said:

Telrad and lower the Finder for me Stu.
I would be breaking my neck or back with the finder high like that from my observing stool.

I may fit a Telrad if I can fit it, but the RACI is pointing towards me so it's really not bad. It was actually just a quick solution to getting an RDF fitted, wasn't meaning to offend so many people's aesthetic sensitivities 😱😱😱🤣🤣🤣

  • Haha 2
Link to comment
Share on other sites

15 minutes ago, Stu said:

wasn't meaning to offend so many peoples aesthetic sensitivities 😱😱😱🤣🤣🤣

You know how sensitive we are Stu, after all how the kit looks is so important in the dark 🤣

  • Like 1
  • Haha 2
Link to comment
Share on other sites

Finders2.thumb.jpg.6d6fcefa103f06bcca8a77a14295e051.jpgFinders1.thumb.jpg.8ea5e155ea3d113b69e63371892ad3cf.jpg

 

With the arrangement above I can land on anything I can see by eye in about 20 seconds flat.  The RDF doesn't even need to be completely aligned because if the optical finder is aligned with the scope a thereabouts find in the RDF puts the star within the optical finder and then landing on the optical finders crossed hairs puts the star into the telescope.

  • Like 3
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.