Identifying stars for alignment

[LordLoki]

Hi all,

So yesterday i finally got my scope out for the first time (aside from day one moon observation). I managed to get it polar aligned (at least i think i identified polaris throgh the polar scope)

Then came 2 star Alignment. I choose Vega and the scope was slewing to the correct position but looking through the scope there where sooo many stars and they where all just tiny little lights. I could not really make out one as Vega.

Its a completly different thing then with my Binos through wich i can identify Vega very easy. in the end i just centered what seemed to be the brightest star but i was not sure i am looking at the correct thing

 

any tips on what to look for??

[michael8554]

It often helps if you say what scope and mount you have. 

If your finderscope is accurately aligned with the main scope, that should be like looking through your binoculars - centre Vega in the finderscope, then Vega should be in the field of view of your longest focal length eyepiece on the main scope. 

Michael 

[Gfamily]

Remembering to align your finder with your scope before you start is important - but if you forget, there's absolutely no reason why you shouldn't take the scope on a detour via a street light or equivalent (or even the moon), so that you can be unambiguously sure that you have the finder aligned with the scope. 

Once you're sure of that, go back to near Vega and get your 1st alignment sorted.

 

[LordLoki]

Hi all, 

Good tip did not even use finderscope. Will try that next time. 

Today I was playing around with my ZWO asi mini camera since the 2" adapter for my dslr is not here yet. I did my polar alignment and then used one star align on Vega again. This time just put the camera in the eyepiece holder try to get focus and centered what I belive to be Vega. 

This hobby needs a huuuge amount of patience that much I know now

Will bother you tomorrow with my newfound questions now it's 2am here so I need to sleep a bit before work. Just wanted to say thanks for the tips and give you a warning for more incoming newbie questions

Good night and clear skies 

[Pitbull]

Good post and I will be following your progress.  I have exactly the same issues at times and find the alignment process difficult, I could not master the finder scope either as its magnification makes finding the correct star difficult.  I changed to a Telrad finder which helped me a lot.  I tend to go for a bright star near a constellation so I can orient myself when the scope slews to the rough position.

[JOC]

RDF's are good as they don't do any magnification so you still only look at a single star.  I got a Y shaped mounting bracket and fitted both a cheap Celestron RDF and a RACI optical finder - with this combo I never looked back.

[michael8554]

I agree with the suggestions to use a RDF (red dot finder) or Telrad, but may not be accurate enough on its own to place Vega in the field of view of the eyepiece in a long focal length scope - you still haven't said what scope you have. 

So I have a Telrad AND a 9x60 finder on my 1280mm FL  LX200GPS. 

Centre Vega in the RDF. then in the finder, then in the eyepiece. 

Michael 

 

 

[LordLoki]

Will check out the RDF see if i can work with that. Also updated my Signature to include scope and mount.

While we are at it another question. I have attached an image taken with the CCD camera yesterday. It is supposed to be M63 but i have no idea 

i shot it with 4 Minutes on the 120mm Mono zwo asi mini. with 80 gain 

but i could not tell if its at focus or not. this setting was looking the best to me. but looking at some videos what kind of detail you get with 4 minutes i am not sure i am doing things correct

 

example.TIF

Edited June 26, 2019 by LordLoki

[wookie1965]

Just one thing if you are using Vega you will not mistake this for any other outlining stars as it is very bright. As the summer triangle is up I use Vega and Deneb.

[LordLoki]

Allright setting up for some testing again tonight going over your tips one question what you mean by aligning the finders cope with my main scope currently I hacked it on the scope a bit since it was the only way I could attach it. See picture. 

Also what eyepiece for the finder which is a 50mm Orion guiding scope. I have plössls 32mm, 15mm ultra wide, 10mm, and 6.3mm

 

[JOC]

Aligning the finder with the scope means turning the adjustment screws that will either be on the finder mount or be part of the finder itself so that if you, for example in the daytime not looking at the sun, were to set the telescope centered on a spire or tree a mile or two away that you then physically change the alignment of the finder so that that also sees the same object in the center of the finder view.  This means that if you then use the finder to find a different object, maybe a distant aerial then center the object in finder and then look through the telescope view that the same object will be at the centre of the telescope view because they are both aligned to see the same object.

Unless the finder is aligned with the telescope view you will find it very difficult to find a specific star or planet with the telescope as you will find it with the finder, but it then wouldn't be in the centre view of the telescope and it can be quite difficult to find things even when you are close to them - it's far easier if they are aligned.

You will need to do it whenever you remove the finder from the scope - so at the start of each session def. check and if necessary adjust the finder alignment.

Edited June 28, 2019 by JOC

[LordLoki]

Allright got it. Will keep that in mind for the next time also very difficult for me because view is a bit blocked to get something far away but I will manage it

[JOC]

Of course you can also play at night.  It is just easier using something a long distance away on land during the day as you have more points of reference as clues when finding the chosen object and you can see what are doing.   I have succesfully done it with things like a specific point on the moon, so it can be done at night. Or you even live without doing it if you have had a play and know exactly how the finder differs from thetelescope  view and you then adjust with your eye that same distance

[LordLoki]

I tell you I can only do it at daytime at the moment. I have big issues identifying stuff in the sky

Currently taking images of some star or galaxy which at this point I have no idea anymore what it is

But it's a good night anyway learning by doing is the Motto. After 2 hours alignment and trying to focus the God damn camera I just put the wide angle eyepiece in and toured wildly through the sky trying to find Vega, Deneb and stuff that just looks nice. 

Then pointed at something put the camera in and just took some 50s exposures. Let's see what I can make of it in the end. Maybe someone can tell already what I am looking at here

[Chris Tardif]

Plate solving is your friend.  This web site: http://nova.astrometry.net/ will allow you to upload an image and it will label the stars and other objects within the field of view.  You can integrate the software into your imaging and alignment process.   One such piece of software can be found here: http://www.astrogb.com/astrogb/All_Sky_Plate_Solver.html 

[LordLoki]

Uhh something new to play with

You guys are awesome and so is this hobby. 

I'm still out shooting some random stuff although daylight is creeping in and the moon is rising above neighbors roof 

 

[JOC]

To focus without a Bahtinov mask, I have had good success using the zoom function on the DSLR back screen, but obviously you have to have found something that you can see first and this may require a brighter star, but it is dead easy to get really good and in-focus shots of the moon using the zoom function and stacking software used on lots of in-focus exposures of the moon will result in an image which I think will really please you.  My Avatar is a single frame taken directly with my DSLR through the EP using this method.  I've got a Bahtinov mask for the camera, but I've only recently learned how to use it and haven't had a chance to properly experiment, but they are supposed to help with focus.  As a tip I have found that to get focus on stars seems to require the camera wound as far out as possible and then backed off just a little and using that I have found that with lots of experimentation I have also achieved focus.

[LordLoki]

7 hours ago, JOC said:

To focus without a Bahtinov mask, I have had good success using the zoom function on the DSLR back screen, but obviously you have to have found something that you can see first and this may require a brighter star, but it is dead easy to get really good and in-focus shots of the moon using the zoom function and stacking software used on lots of in-focus exposures of the moon will result in an image which I think will really please you.  My Avatar is a single frame taken directly with my DSLR through the EP using this method.  I've got a Bahtinov mask for the camera, but I've only recently learned how to use it and haven't had a chance to properly experiment, but they are supposed to help with focus.  As a tip I have found that to get focus on stars seems to require the camera wound as far out as possible and then backed off just a little and using that I have found that with lots of experimentation I have also achieved focus.

I used the Focus section in Backyard EOS once i had figured out how many distance i needed to see at least some giant out of focus bubbles . That worked well for me once i got the hang of it.

On the Moon i also used the Zoom. Did not manage to get as nice of a picture as yours but i was proud given that was my first shot through a telescope.

Have to say was a great night and the pictures i managed to get could be worse. Also attached my very first telescope picture from last week of the moon. 

[JOC]

well that's not a half bad attempt at the moon is it?  If that's one of your first attempts I should pat yourself on the back.

[LordLoki]

Thanks it was my first day with the scope after hours of trying to get polar alignment and star alignment I was frustrated a bit and decided to go for the big bright full moon

Still took me a while to get to see it through the scope. Then spend another hour to get focus because I never did eyepiece projection. But then finally I got this picture and I was a very happy man

[LordLoki]

Hi all, 

Just want to keep you all updated and leave my experiences here for others. Today is not a good night here for stargazing but it's not horrible either so I thought it's a good idea to test out platesolving. 

It took some fiddling with APT and drivers for the mount etc but then I got it rolling. Will write more details about the process and the issues in a separate thread but after a lot of trial and error I managed to point at Deneb and from there I plate solved myself to the North American nebula. Shitty conditions today for imaging but I don't care will shoot a couple of 60s subs and see what I can make of it. 

I think that I mess up the polar alignment in the beginning because I am always just a bit off. For example when I goto Vega it landed on lyr. When I did goto on north a American nebula I landed on 75 cyg. But platesolving and goto++ brought me to the right place from there

 

[cletrac1922]

On 29/06/2019 at 06:35, LordLoki said:

Allright got it. Will keep that in mind for the next time also very difficult for me because view is a bit blocked to get something far away but I will manage it

 

Loki

Better off aligning finderscope daylight

Pick an object in distance, like mobile phone tower, then adjust the two small screws, so finderscope, has same object as camera or eyepiece

[Geoff Lister]

I have Skywatcher's Synscan GoTo on my Skyliner 10" Dob. and Skymax 5" Mak. I usually align using its "Brightest Star" 2-star alignment feature. I spent some time with the Stellarium program on my PC, altering date and time, to identify the brightest stars likely to be visible from my observing position in my back garden. I produced a table of 18 stars, and for the middle of the month, for each of the 12 months, identified 3, 4, or 5 stars visible at dusk, giving adequate azimuth and altitude separation for good Synscan alignment. The table notes the rough compass direction and altitude (with a single bright star, it is difficult to identify the constellation to which it belongs). Synscan has no idea of natural obstructions, such as houses, fences or trees, so may suggest bright stars hidden behind something; the table helps me to avoid these, particularly for the second alignment star. I produced a similar table for 1 hour before dawn; not of much use, this time of year, but viable for the winter months.

Last night, just after 10pm, with a reasonably clear sky, Jupiter was bright towards the south. It was still quite light with only a few stars just visible. My table had identified Vega and Arcturus as good alignment stars for July. I used the brightest star alignment in its 'planet + 2-star' mode, manually pointing at Jupiter, (and checking that it was at the intersection of the finder's cross-hairs) and then stepped through the suggested stars to go, with automatic slew, for Vega, then Arcturus. GoTo alignment and subsequent tracking of Jupiter were spot-on; as it was for Saturn, when it had cleared adjacent trees, at about midnight. Then the clouds rolled in 😠.

By performing alignment at dusk, it is much easier to avoid aligning on adjacent, but incorrect, stars. You only need 1 star or planet to be visible to the naked eye for the first, manual, slew; after that, the software gets the next star close to the middle of the finder, and, if you start with the mount levelled, probably visible somewhere in a low-magnification eyepiece, requiring minor adjustment to centre the view.

Geoff

[LordLoki]

Hi Geoff, 

Thanks for the post. I do my polar alignment now mostly at dusk since it makes it much easier to get Polaris in the polar scope. As for alignment I now use the mighty power of platesolving in APT and that works super very well. But I also worked on my 2 star alignment and doing it at dusk helps a lot. 

Greets loki