DIY Dob Setting Circles

[mike-h]

It posted that one!

Right, you wont be able to make a wraparound ribbon type like mine because it would be too small on the neck of your mount.

tbc...

[mike-h]

However, you could make 2 card discs. The top one will have an enlarged photocopy of a protractor on it and will attach to the neck just above the alt bearing. The other one goes underneath and is slightly larger. It has a pointer on its edge which you can rotate and blutack in position once its aligned

tbc

[mike-h]

The discs would need to be big (bigger the better for accuracy). It wont look great but it will work.

One issue-when you point the scope up, the back end will hit the discs. Maybe make a 180 degree south facing version which you can rotate around when u want to observe the northern sky.

Best I can do ideas wise!

Mike H

[kniclander]

well, I made mine today - the super lazy way - I just stuck scotch tape round the upper base and marked off every 10 deg with a white pencil (twice as the first time I got the cm/inch conversion wrong and had 37 marks instead of 36 ).

My only slight mod was a paper clip instead of a pin on the little 10 deg marker so it can be easily moved on the marker.

If it works, I'll strip off the tape and re-do it directly to the base with white nail varnish

Thanks MikeH - great idea:hello2:

[mike-h]

I hope it works out well and your as happy with it as I am. Let me know how you get on, especially if you make any adaptions for the better.

Have fun

Mike H

[kniclander]

cheers Mike - I need to do it again as i was not accurate enough marking off the 10 deg points direct on to the tape on the base:rolleyes:. But it's going in the right direction

[Rogue Leader]

Could someone just check Rob`s site for me please, I cannot get anything to happen. I am sure it is something I am doing wrong but it all seems self explanatory. I have tried it in IE and Firefox but do not seem to get a PDF at the end. Have tried circles and linear strips.

Cheers

Mike.

[rwillett]

Just seen the post, it's not working and no idea why.

I'm looking at it now.

Rob.

[rwillett]

Website back up. It turns out a PHP upgrade seriously broke something. <spit>.

Rob.

[Rogue Leader]

Thanks very much Rob.

[rwillett]

If you do create anything useful could you post it to me so I can incorporate it into the new version coming up.

The new version is far more up to date and has lots new features including templates, history lists, Hartman masks, Bahinitov masks.

Rob

[ee001]

I was thinking of getting an Astro-Fix locator for my 12" dobsonian but am now thinking whether I should try doing this. Obviously this would be a much cheaper option.

[rwillett]

oh I see - I had assumed that it would print out lots of little strips that you would stick to the base one by one. I don't have access to printing any paper larger than a4 anyway. No prob.

cheers

dan

I have now put the ability to tile print very large pages, e.g. A0 will print out around 25 A4 pages. There are no special user requirements, just a normal PDF reader and a printer. You can specify whether the tled output is A3, A4 or Letter.

This functionality is only available on the new settingcircles website (which is not yet released) but if you send me the dimensions I can generate an appropriate PDF with the right number of pages.

Rob

[irishbloke]

I'm wondering if it is necessary to have the dob base level if using setting circles and a wixey for alt. Is the alt not always going to be correct as it is measuring the angle internally?

thanks

Brian

[Doc]

I'm wondering if it is necessary to have the dob base level if using setting circles and a wixey for alt. Is the alt not always going to be correct as it is measuring the angle internally?

thanks

Brian

I have found that if the base is not level the wixey doesn't always read accurate. Take time to level your base and it's accurate to .25°

[insomnia]

Mike I would love to know the measurements that you used as I have the same scope and am looking to do the same. How many cm/mm is it to each 5 degree mark? My calculation has come up with 2.26cm per 5 degree, does this sound right?

[John Mckay]

Hi mike, planning to do this tomorow, is it difficult to make the degree marks accurate? Great idea btw!!

[ErikRuud]

I know this thread is a bit old, but I found it while looking for information on making setting circles for my new Bushnell ARES 5

After looking at Rob's site and some other ones, I decided I wanted mine to be a little bit different. Working in Inkscape I came up with this.

Then I decided to make something a little more generic that others could use.

You can get the .svg file here.

You should be able to open this in anything that understands .svg and scale it to size as needed.

I created it with multiple layers, so that different layers can be switched on or off to get different looks. In particular the numbers can be clockwise or counter clockwise depending on how you want to use the circle.

The compass rose can also be turned on off, or have the east/west flipped to match the numbers.

All of the text has been converted to paths so that you do not need to have the same font files.

[Gina]

Very nice

[Rapallokid]

Old thread but usefull.

This can be my project for this weekend.

[tsmith001]

Hi

I think i understand what to do

But how do you align your telescope to start?

Do you find say Saturn , then place the telescope in the 251deg position?

thanks

[valleyman]

Spot on, did this same to a dob I had 2 years ago. and it worked a treat. Simple but effective.

[estwing]

just done mine today....10mins a doddle !

[stevetynant]

Hi

I think i understand what to do

"But how do you align your telescope to start?

Do you find say Saturn , then place the telescope in the 251deg position?

thanks" All - I do is find polaris which is easy and then make sure the needle is pointing to zero (or 360 depending where you started from) on your setting circle. If you use a pointer that's effectively sat on the floor independant of the Dob and doesn't move make sure the setting circle is running counter clockwise not clockwise (which I did first time and couldn't find anything)