RA setting circle.

[emyliano2000]

Hi guys.

I'm having a little trouble trying to work out the RA setting circle.

I'll tell you what I've done.

So after I leveled the mount, I put it on home position and got it polar aligned which I think it was quite accurate with the PolarFinder app on my phone. As far as what I understood the RA setting circle must be set on 0 when you finish with the set up.

When I'm trying to go after something I can't see with my naked eye I just go to the closest object I can see, get the coordinates from Stellarium, set the RA to those coordinated and move the scope until I get to the coordinates of the object I'm trying to see.

This is how I found Bode's Nebulae. I centered my scope to Dubhe from Ursa Major and set the RA to those coordinates. I rotated the mount to the Bode's DEC coordinates and looking through the eyepiece I moved the mount on the RA axis until I found it. The RA coordinates weren't exactly what the Stellarium was saying they should be but they weren't far off.

My question: Do I have to do this every time I'm trying to go to an object I can't see with my naked eye?

If I start from 0 on the RA when the scope is on home position and polar aligned and try to go to a star that I can see with my naked eye using the coordinates, I don't get anywhere near the object.

EQ5 mount. I read the top lines on the RA circle, right?

Cheers.

 

[Dr_Ju_ju]

General consensus would place the RA circle on an EQ5 to be inaccurate\useless (it is on mine) and so do not use it. That is why most peeps use goto\pc control...

[emyliano2000]

1 hour ago, Dr_Ju_ju said:

General consensus would place the RA circle on an EQ5 to be inaccurate\useless (it is on mine) and so do not use it. That is why most peeps use goto\pc control...

After reading many topics on SGL I realised the setting circles are not much of a use on the eq5 but I still wanna understand the way they work and that's why I wouldn't wanna upgrade to a goto just yet. I'm trying to learn my way on the night sky, learn the constellations and at least the major things that can guide my way when trying to find things. There are many things that I could miss if I would upgrade to a goto but thanks for the advice.

[wimvb]

Not many people use setting circles, but you are doing it right. Go to a bright star, set the circle to that stars RA, then move to your object.

There is a section in the (EQ5) manual about using the setting circles. The description matches your procedure. Forget about the setting circles in the home position.

BTW, this is a great way to visit targets that are not in the handcontroller database.

Good luck

[kens]

Because the RA setting circle does not move with the earth's rotation it needs continual recalibration. If you are using Stellarium I'd suggest you display the hour angle and set the RA setting circle to the Hour Angle. That way you don't need to change the setting circle through the night. You'll notice that the hour angle in Stellarium is continually changing

[emyliano2000]

58 minutes ago, kens said:

Because the RA setting circle does not move with the earth's rotation it needs continual recalibration. If you are using Stellarium I'd suggest you display the hour angle and set the RA setting circle to the Hour Angle. That way you don't need to change the setting circle through the night. You'll notice that the hour angle in Stellarium is continually changing

Yes, I was thinking of doing that.

[skfboiler]

That is awesome that you are using the setting circles and having success.  Before I bought my Goto scope I used the setting circles on my little EQ-3 mount and had some success.  With my light pollution from Chicago I was able to find several objects that I could not star hop to using the setting circles.  The key is getting a real good polar alignment.  That is how I found the globular M5.  I failed star hopping to it because there were no stars to.  Therefore, I centered the scope on Arcturus and got its RA and DA.  Then set the RA and DA for M5 and slewed to it.  It was not in the FOV, but with a quarter turn of the RA knob there it was.  Other times objects are in the FOV perhaps near the edge, but it was there.

[N3ptune]

in this video setting circles explained and why they don't work (according to the speaker). I watched this video a few month ago I think it's interesting.

https://www.youtube.com/watch?v=geQszAVWMok&list=PLhvRte7lAzo67gXd-qO6TJwEBFOPT1T5M

For me the fun of astronomy is to search the sky, slowly, and take the time to appreciate the various things all around (like a trip where your going to a destination and finally you explore another unexpected region). There could never be any need for an upgrade to a goto device for visual observation.

 

[Gazabone]

For me, they work wonderfully well.  I use them quite regularly on both my EQ 3-2 and NEQ6 mounts.  The main reason in my experience for problems is that that RA circle binds in places - you should be able to release the clutch and rotate the mount in RA through 360 degrees, the circle should follow the movement and read the same setting after 360 degree rotation that you started on.  If it doesn't then you'll need to sort the mount out.  The other thing is that you need to make sure your mount is level otherwise you may have problems with declination.

Have you seen this video?

There's also some resources on the Cornwall Astronomy website you might find useful.

http://www.cornwallas.org.uk

They are worth percivering with.  All I can say is that I don't have problems finding objects using them.

Good luck.

??

 

[Peco4321]

1 hour ago, Gazabone said:

For me, they work wonderfully well.  I use them quite regularly on both my EQ 3-2 and NEQ6 mounts.  The main reason in my experience for problems is that that RA circle binds in places - you should be able to release the clutch and rotate the mount in RA through 360 degrees, the circle should follow the movement and read the same setting after 360 degree rotation that you started on.  If it doesn't then you'll need to sort the mount out.  The other thing is that you need to make sure your mount is level otherwise you may have problems with declination.

Have you seen this video?

There's also some resources on the Cornwall Astronomy website you might find useful.

http://www.cornwallas.org.uk

They are worth percivering with.  All I can say is that I don't have problems finding objects using them.

Good luck.

??

 

Just watched the video and it seems to make sense. Downloaded your star co-ordinates sheet and found a similar one for Messier objects:

http://messier.seds.org/xtra/supp/data_gc.html

I will try this out soon as I often struggle, thanks and I'll let you know how it goes. 

[Gazabone]

3 hours ago, Peco4321 said:

Just watched the video and it seems to make sense. Downloaded your star co-ordinates sheet and found a similar one for Messier objects:

http://messier.seds.org/xtra/supp/data_gc.html

I will try this out soon as I often struggle, thanks and I'll let you know how it goes. 

Thanks, if I can be of any help, please let me know.  It really is easy once you've done it a few times. To start with it might be worth trying moving from one bright star to another within the same constellation. That way, if your target star isn't in the eyepiece, you can easily see how far out you were and figure out what went wrong.  However, you'll soon be finding the faint things!

All the best. 

 

[Peco4321]

23 minutes ago, Gazabone said:

Thanks, if I can be of any help, please let me know.  It really is easy once you've done it a few times. To start with it might be worth trying moving from one bright star to another within the same constellation. That way, if your target star isn't in the eyepiece, you can easily see how far out you were and figure out what went wrong.  However, you'll soon be finding the faint things!

All the best. 

 

Just need to be patient waiting for clear skies!!

[Peco4321]

Found a better list:

http://www.kenpress.com/MessierListObjects.pdf

Only issue I may have is that the RA Circle dial sometimes sticks. Sprayed a bit of WD40 but doesn't seem to have made any difference. Any ideas?  

[N3ptune]

8 hours ago, Peco4321 said:

 

Only issue I may have is that the RA Circle dial sometimes sticks. Sprayed a bit of WD40 but doesn't seem to have made any difference. Any ideas?  

Don't put too much hope in them?

 

[Peco4321]

1 hour ago, N3ptune said:

Don't put too much hope in them?

 

In that list or using RA circles??

[Gazabone]

5 hours ago, Peco4321 said:

Found a better list:

http://www.kenpress.com/MessierListObjects.pdf

Only issue I may have is that the RA Circle dial sometimes sticks. Sprayed a bit of WD40 but doesn't seem to have made any difference. Any ideas?  

Ah, that will cause problems. Maybe it's a case of stripping it down, making sure the circle hasn't buckled at all, applying a light grease and reassembling.

if they continue to stick, the closest you'll be able to use them is to make sure when you come to find your target, make sure the declination is correct, at least you'll only have to "fish around" in the RA axis (at least it will only be one axis). IMHO that will still be easier than star hopping (personally I really struggle with that), but if you can get the RA circle to rotate properly, they work really well. 

[N3ptune]

Peco4321

The list is fine.

[N3ptune]

Peco

There is this website too with what's looks like the entire NGC with different configuration like this one:

http://www.deepskywatch.com/files/dso-guide/DSO-guide-7000-const-mag.pdf

7000 DSO's listed by constellations and magnitude, in some case the surface magnitude information which is great.

[Peco4321]

25 minutes ago, N3ptune said:

Peco

There is this website too with what's looks like the entire NGC with different configuration like this one:

http://www.deepskywatch.com/files/dso-guide/DSO-guide-7000-const-mag.pdf

7000 DSO's listed by constellations and magnitude, in some case the surface magnitude information which is great.

Wow that's a big list, think I'll bookmark it rather than print 109 pages out ?

[N3ptune]

Peci4321 it's an expensive project for a printer heheh.

I use the big list for regions like the one bellow (from my field atlas), it's in Coma Berenices and there are many faint galaxies to search for. I can look at the large DSO list on my computer before I go outside and pick the galaxies with the highest surface brightness. It's a way to build a good observation program.

[Peco4321]

15 minutes ago, N3ptune said:

Peci4321 it's an expensive project for a printer heheh.

I use the big list for regions like the one bellow (from my field atlas), it's in Coma Berenices and there are many faint galaxies to search for. I can look at the large DSO list on my computer before I go outside and pick the galaxies with the highest surface brightness. It's a way to build a good observation program.

All great advice thanks.

Still fairly new to this and really only just getting to grips with making observing plans. It's a good time of year though to be practicing so come the darker skies I'll hopefully be in a better position.  Got loads of sites bookmarked and will print some out. 

[Jimtheslim]

I had setting circles on my Skywatcher eq2 and straight away realised they probably wouldn't be accurate enough. Just bought a Telrad for my new dob and can't wait to get started with it!

[Peco4321]

Tried this last night and had no success at all.

I chose M13 to test it on as I know where it is. Centred on the star above M13 and changed the RA circle to its coordinates off Stellarium, and then moved to the coordinates of M13 off one of the lists above and I was nowhere near. Tried it a few times from the same star and then the star below M13 and still not close. I then centred M13 and checked the DEC coordinates and it didn't seem to match what it should have been. So that's problem 1. 

Then I noticed there are two pointers on the DEC circle to the numbers, on opposite sides of the circle. They point to different numbers!  Problem 2. One read 40 something and the other read 30 something. 

Not sure where I go from here ?

Pictures to show problem 2. One side at 0, the other side at about 6. Shouldn't they be the same?

[Peco4321]

Video clip also to show how it seems to stick and not move freely. Would really like this sorting, so any ideas appreciated. Thanks. 

IMG_4969.MOV

[michael8554]

So long as you use the same mark on the mount body it shouldn't matter.

I'm not an EQ mount user, but I see no mention of setting your Dec circle. Is it on zero or 90 when pointing at the Pole, and are you rotating the mount in the right directiion on the scale after aligning on a nearby star?

Michael