139 replies to this topic

[Napp]

I have heard the advice about clubs and star parties almost everywhere, but I've always been a shy lone wolf.type, so its a bit intimidating meeting new people, although I will say, if any community would ease my worries it would be this one.


Nitsky, I will admit the nights have had bad seeing, stars twinkling a lot, but other than that clear skies, no clouds, fog, etc.I have never looked through a telescope before, I have used mine every night I've had a chance too, buts been maybe 10 days max.

NTPH, yes, I definitely know I'm not going to see what I see in pictures, but still a bit underwhelming at what I am seeing. For the double star I tried Sirrus, maybe its the wrong star to focus on? I think I really need to make a new friend who.knows about this stuff, but that's always been an issue with me my entire life.

Seattle Scott, I am looking at buying some.good filters, Lumicon, Astronomik, etc, but dam they are expensive. I am leaving it out for more than hour, do you think I should give it more time. I have a fan on it that I have never used, maybe that is the problem. Also, temps have been varying a lot so maybe that's it?

 

Welcome to the DOB club!  I think a lot of what you are seeing has to do with expectations and lack of experience.  Don't worry about hanging with an astronomy club.  A lot of those folks are like you.  You may run into a a know-it-all but most are nice folks who want to help.

 

Planets are not easy.  They are bright but very low contrast objects.  It takes experience at the eyepiece to really 'see' them.  Just keep observing and you will start to pick out details.  Planetary observing requires steady skies.  'Seeing' is the measure of how steady the skies are.  This has nothing to do with how clear the sky is.  In fact the clearest skies are often quite turbulent.  A good example is how clear the sky can be after the passage of a cold front - very clear but quite turbulent winds aloft.  If you live where jet streams tend to be overhead it will be difficult to catch a steady sky or good seeing.  Allowing your scope' to acclimate to air temperature is very important. Collimation is critical to seeing detail.  Practice getting it right.  Club members can help you with this.  Just keep trying and build your experience.  Observing with club members can be a big help coaching you in seeing details.

 

Sirius and the Pup are extremely challenging.  You picked a very hard one.  Seeing and collimation must be very good to have a chance.  Sirius is so bright the Pup so faint it can be lost in Sirius' glare.  The Pub can hide behind a diffraction spike.  Go for something much easier.  Look for a wider separation and less difference in visual magnitudes.  

 

Right now I would advise against spending money on filters.  Get more experience.  Club members can show you views through filters.  They don't necessarily make a huge difference.  However, once you have more experience observing they will be very helpful with certain objects.  As to cost - well you get what you pay for.  Observing with a club you can determine when a particular filter is worth it.

 

The main thing is to keep observing.  I got back into observing about 10 years ago.  One of my first nights observing with a club I had my scope pointed at the Andromeda Galaxy.  I was quite happy with what I was seeing.  A younger club member introduced himself and asked to have a look.  He agreed that the view was quite nice and started identifing features he was seeing,.  I put eye to eyepiece again and couldn't see those features.  I actually wondered if he was seeing them or playing with me.  Well, he was indeed seeing them and I saw them, too, with more experience.

[GolgafrinchanB]

I am leaving it out for more than hour, do you think I should give it more time. I have a fan on it that I have never used, maybe that is the problem. Also, temps have been varying a lot so maybe that's it?

100% use the fan! I believe your telescope uses the GSO F/5 mirror which is a 14lb, 1.5" thick mirror. That thing is not going to keep up with the night's cooling without a fan!

 

Also, keep the fan on all night. If vibration is a problem (easy to check, momentarily turn off the fan and see if view improves) then figure out how to isolate the fan. Big dobs need fans!

 

This won't help with nebula brightness, contrast, or any of that, but it sure will improve your planetary and double star views!

[Dave Mitsky]

Unfortunately, many novices have unrealistic expectations about telescope performance due to the ubiquitous color images of the planets and deep sky objects.  For the most part, the universe is monochromatic as seen through an eyepiece due to the poor color response of human scotopic or night vision and the planets are quite small.  

https://isle.hanover...icScotopic.html

 

The Astronomical League's graphic at https://www.astrolea...copes85x-11.pdf illustrates just how small the bright planets are in angular size compared to the Moon.

There are a limited number of deep sky objects in which color to a greater or lesser degree can be seen depending upon the aperture used, the conditions, and the color sensitivity of the individual observer.  High surface brightness planetary nebulae like NGC 3242, NGC 6543, NGC 6572, NGC 7009, and NGC 7662 are some examples.

https://www.cloudyni...hat-have-color/

 

There are quite a few colorful stars, however, binary and carbon stars for example. 

 

 

 

[Neanderthal]

Keith, I live in Santa Clarita, Ca

Best advice I think I could offer is either seek out a club or post up an ad or request for help from an individual here on the forum. Folks in this hobby are very eager to help out, it's not like asking another fisherman to show you his honey hole, lol.

[Playa17bk]

I'm definitely going to try all these suggestions. The main one I am still confused on is the mirror clips, but what I'm going to do is get a good look inside and figure out how that whole mechanism works and looks like, hopefully I can figure out this clips thing and keeping a distance on them.

[JohnBear]

Best advice thus far: Make some new friends at a nearby astronomy club! You will learn a lot and get to see and observe what others use. 

 

As for expectations - keep it real! Compare your telescope 1) to what your eyes can, and 2) to what you can visually see with the various telescopes others in your local clubs have.. Star parties are good reality checks for our expectations.

 

Have fun and enjoy the long learning curve!

 

Afterthought:  The majority of problems with telescopes are mechanical - usually caused by a loose nut on the focuser!

Edited by JohnBear, 27 February 2025 - 11:01 PM.

[SeattleScott]

DGM NPB is an affordable, but good, nebula filter.

[Playa17bk]

Ok, now I can definitely see the clips you guys are talking about. How in the world would I know how tight those are, I mean they are all the way in the bottom of the huge tube and from what I can see have no access from the back.

[Napp]

Ok, now I can definitely see the clips you guys are talking about. How in the world would I know how tight those are, I mean they are all the way in the bottom of the huge tube and from what I can see have no access from the back.

To check them you have to remove the mirror and cell from the tube to access the clips.  There should be a very small distance between the clips and the surface of the mirror - they shouldn’t actually touch.  If they do they can bend the mirror slightly.  However, I would not think that is happening unless the telescope had a previous owner who removed the mirror from the cell and reinstalled it incorrectly.  There will come a time in the future when the mirror will need to be cleaned.  That’s when you would need to remove the mirror and cell and then separate the mirror from the cell.  It’s good to get an experienced person to help you when it’s time.  But that should not be anytime soon.

[Playa17bk]

From what I am reading, it seems that the manufacturers are tightening these clips for shipping reasons and I should definitely pull it out and see if the clips are too tight. I can't seem to find any instructions or videos on how to do it though. I think I can figure it out, I'm pretty handy. Stay tuned folks, my next post will probably be a wanted add in the classifieds for a new primary mirror

[Napp]

From what I am reading, it seems that the manufacturers are tightening these clips for shipping reasons and I should definitely pull it out and see if the clips are too tight. I can't seem to find any instructions or videos on how to do it though. I think I can figure it out, I'm pretty handy. Stay tuned folks, my next post will probably be a wanted add in the classifieds for a new primary mirror

It's not hard.  Just be careful and remember how it goes back together.  If there is any space between the clips and the mirror surface you should be good.  However, I would expect distortion of the image if the clips were too tight.  Other things like proper positioning of the secondary and collimation should be addressed before taking the scope apart.  Somone at an astronomy club should be able to look at your scope and determine whether you need to look at the mirror clips.

[Daveatvt01]

A few good doubles this time of year are:
Rigel, in Orion- bright primary, close dim secondary
Polaris- also bright primary, close dim secondary (northern hemisphere only)
Castor, in Gemini- two close stars of similar brightness and color
Sigma Orionis, in Orion- a multiple star system with 4 visible components, all more or less in a line (one of the middle two is much brighter)

Higher magnification will separate some doubles that can’t be seen at lower magnifications too.

Good luck!

[Dave Mitsky]

Some other good double and multiple stars at this time of year include Struve 761, a triple star close to Sigma Orionis, h3945 (145 G Canis Majoris), a very colorful double star nicknamed the Winter Albeiro, Beta Monocerotis, which is perhaps the best triple star in the heavens, Almach (Gamma Andromedae), Eta Cassiopeiae, Iota Cancri, and Algieba (Gamma Leonis).
 

The following links lead to lists of binary and multiple stars:
 

https://www.astronom...t-double-stars/
 

http://www.skyandtel...h/double-stars/
 

https://www.astrolea...ectList2021.pdf
 

https://gardenastron...m/double-stars/

[Dave Mitsky]

Lists of colorful carbon stars can be found at the following URLs:
 

http://www.skyandtel...-red1203201401/
 

https://www.astrolea...bonStarLog3.pdf
 

http://www.astrosurf...iar2/carbon.htm
 

https://www.johncbar...-star-list.html
 

https://amateurastro...r-carbon-stars/
 

https://calgary.rasc.ca/redstars.htm

[vtornado]

Hi everyone, I'm a new member and bought my first telescope a month ago (Apertura AD12). I'm a bit disappointed in what I am seeing. Planets are in and out of focus even after adjusting the focuser. 

 

This happens all the time.  It is atmospheric turbulence.  You can either chase it with the focuser or stay put and let the planet randomly come into focus.

 

Everything seems to have a cross shaped glow.

These are diffraction spikes from the spider.  I think they are pretty, others hate them.

 

If I do see nebulas they are faint and have absolutely no color. 

Nope they don't, color comes from a camera.  Maybe Orion has a tinge of green in a 12 inch reflector, all others are grey

 

Can never see a double star at all. Try Mizar or the Double Double. (Epsilon Lyra) With the double double there is a lot of separation between the primaries so that should be easy.  With good seeing each pair of the double also has another companion about 2 arc seconds apart.   Albiero  is beautiful and an easy split.

 

 

I have read so many topics on this forum and nothing seems to help.

 

 

Not sure if its just my crappy eyepieces (Orion Plossl series)  There is nothing wrong with an Orion Plossl.  Narrow field yes, Small eye relief yes, but the center of field should be as  sharp as any other eyepiece.

 

 

or something wrong with my eyes (have an appointment with optometrist coming up). I collimate every single time with a laser, yes I have collimated my laser as well. 

Use a barlow with your laser.  Otherwise you will have registration errors.

 

http://www.smartavtweaks.com/RVBL.html

 

find a bright star and center it. slightly defocus until a set of rings appears. they need to form a perfect bullseye pattern.  If  the bullseye is skewed you are not collimated.

 

I let my scope acclimate over an hour or more every night.

point the scope at a bright star and defocus more until you see a big white disk. If the disk is all wavy like there are ants crawling across it, either your mirror is hot, or your skies are turbulent.  Where is the scope stored?   Inside?  I had a 12 inch dob and cooling the mirror 20 degrees F took around 2 hours to be acceptible.  longer to be perfect.   Running your fan will lower time but it is not a miracle worker.

 

 

Edited by vtornado, 28 February 2025 - 12:19 AM.

[Dave Mitsky]

The following links are to deep sky object observing lists:
 

https://www.messier-...er-object-list/ (the Messier Catalogue)
 

http://messier.seds....r/sac110bn.html (the SAC's best objects in the NGC list)
 

http://messier.seds....r/rasc-ngc.html (the RASC's finest NGC objects list)
 

http://www.tyler.net...pot/saa100.html (the sci.astro.amateur 100 list)
 

https://observers.or...eye-candy-list/ (The Eye Candy List)
 

http://www.ocrasc.ca...l Splendor.html (The All Splendours, No Fuzzies Observing List of 160 objects)

 

Celestial object list generators can be found at http://www.virtualcolony.com/sac/ and https://telescopius.com/ and http://tonightssky.com/MainPage.php

[Dave Mitsky]

While it doesn't deal with using a telescope directly, you may find some of the information on astronomy, amateur astronomy, and observing presented in my post (#22) at https://www.cloudyni...mers/?p=5184287 useful, Playa17bk. There are sections on various books, observing guides, the Moon, the planets, star-hopping, stellar atlases, planispheres, planetarium programs, astronomy apps, deep-sky objects, lists of worthwhile celestial objects to observe, binocular astronomy, urban astronomy, and other related topics.

[Bearcub]

My unofficial telescope rating system:

 

to do list:

 

1)  Pickering scale

https://www.damianpe...m/pickering.htm

 

Aim telescope at 1 or 3 brightest stars with naked eye and use around 200x magnification. What you see? If its 1-4 then dont be too sad. optional: If its 5-7 then insert some eyepiece or barlow combination to reach 300 or 350x magnification on such star.

 

2) Measure time how much you spent looking through telescope on fun and easy sky objects like moon or planets, dont judge how much you spend looking through telescope on hard targets. Aim for most easy magnification ~ 100x or 150x magnification. However 12" dob should let you enjoy sky at 300-350x magnification most of the nights and in some nights 400-450x.

 

relative scale for to convert words into numbers:
4 - barely watchable (not worth looking..)
5 - watchable (for 5min, 10min)
6 - enjoyable (easy 20min viewing)
7 - very good, almost amazing (can loose track of time)
8 - amazing (if its whole time, then nobody can drag my away from a telescope)
9 - best ever.. ( i will fight you if you interrupt me jk )

 

so if you have moments where you lose the track of time while watching object, then it means the night is a 7 out of 10.

However it is telescopes' job to give the best viewing experience each night, so the sky cannot take full blame every single time.

 

If you truly find yourself not enjoying the view at lowest magnification like 100x or 150x for more than 5 different nights in a row then the telescope is no good for your skies!

 

If you find that you enjoy skies half the time - meaning 5 nights out of 10, then the telescope is no good for your skies either! It will kill your hobby sooner or later.

 

personal notes: i have 10" dob and i was annoyed by spider vanes effect during viewing also, and almost always pickering scale for me was 1-4 almost always even if dob was permanently outside, i was enjoying(6) the moon or planets at around 200x magnification most of the nights but i was feeling urge to look at other targets... My laser even with barlow bounced back unto itself.

 

After i got refractor i am glued to the target. Most nights become very good, almost amazing, or enjoyable..

i would say:

1 night out of 10 now is barely watchable 4

1 night out of 10 now is watchable            5

3nights out of 10 now are enjoyable         6

3nights out of 10 now are very good        7

2nights out of 10 now are amazing          8

had 2 nights that were at 9.

 

meaning i just look at same sky object like a loser without desire to change the target, if i start with moon then i look at it for few hours, and i have no desire to change it, however because i view through balcony i have urge to not waste time and force myself to look at planets otherwise it might take months until those planets rotate in the sky and again appear in my view at night.

 

in conclusion: i would guess your skies are just not suitable for dob. But you must test it out 10 different nights... of course now its winter-spring so the air might go from below freezing to above freezing but it is after all just an excuse... my refractor performs in all conditions always better than dob or maksutov. However refractor is very expensive.

[Dave Mitsky]

The articles at the following URLs discuss the steadiness of the atmosphere which is known as seeing:

 

http://www.damianpeach.com/seeing1.htm

 

http://www.damianpea...m/pickering.htm

 

https://skyandtelesc...ing-the-seeing/

 

https://www.skyatnig...nomical-seeing/

 

https://sentinelmiss...nomical-seeing/

 

[Jon Isaacs]

You might find a local club and get an expert to look at the scope.  It is very difficult to diagnose these things remotely.

 

"Cross shaped glow" could be astigmatism in the scope or in your eye.  Although the diffraction pattern from the secondary support (spider) could also make cross shaped patterns.  One diagnostic for cross-shaped patterns, is to rotate stuff and see if the pattern rotates with anything.  If you rotate your head, does the pattern follow you head or the scope?  If you rotate the eyepiece, does the pattern rotate?  Do you see these patterns more at high or low magnifications?  Sometimes one of the mirrors is defective, or is mounted too tightly and becomes bent.

The way I read this: (I know you know this and much more)

 

A cross shaped glow is normal for viewing the planets, it's the sum of the diffraction spikes for each point on the planet.  If it were astigmatism in the optics or in they eye, it would not be a "glow."

 

Seeing, cooling and collimation are the normal bugaboos of a 12 inch Dob..  Winter seeing at northern latitudes is not normally stable.  An effective fan cooling the mirror for more than an hour is a start.  Collimation using a laser, use the Barlowed laser for the primary.

 

Double stars:  Try Castor.. it's about 5 arc-seconds

 

Jon 

[PalomarJack]

PalomarJack I come from the school of go big or go home, so I had to go with the big ole dob

Sounds like that "school" needs an education itself. This is not the place where biggest is best, all sizes of apertures and architectures of telescopes have their purpose. The problem with something like a telescope is it can be overwhelming and many give up when starting small will gain experience without the aggravation of handling a big instrument. You have enough to do learning about amateur astronomy, managing a big telescope as one does will tax your patience. All I can say is, you'll find out soon enough. It may be the point where you either just get something smaller to learn on or give up, seen it many times.

 

Part of the problem, as you will find out is a 12" scope has half the true field at lowest mag of say a 6". And one quarter the field of an 80mm. It makes a huge difference when learning this hobby. After all, it's supposed to be fun, not work.

 

Here, let me break it down, a 12" has at maximum true field of about 1.7 degrees at lowest useful magnification, 48X. A 6" is about 3.5 degrees at 24X. This alone means a great deal when you are looking for a dim and difficult DSO (deep sky object) with an alt-azimuth mount and Telrad. To make matters worse, you did not get the best eyepiece with that instrument. When it comes to finding dim objects without setting circles or goto mount and the needed eyepiece, you "go wide, or go home". That means spending even more money on a very expensive eyepiece just to find your targets, when a much less expensive one with a smaller aperture serves much better to learn on.

 

But, like I sad, "What's done is done", find someone to help, in person, or you will be selling it in a year or two out of frustration. But seriously, consider a smaller instrument for certain tasks and good binoculars, you're going to need them anyway.

Edited by PalomarJack, 28 February 2025 - 07:12 AM.

[TheChosen]

I know this is not what you want to hear but this is why it is good to start with an 8". It is easier to operate and establishes a good baseline from which to decide whether it is worth it to go even bigger.

 

What you are experiencing with the 12" is more or less normal. You will never see color in DSOs with very few exceptions (Ring planetary nebula or few other planetaries, maybe a hint in Orion).

 

Your eyepieces are definitely not helping things but even if you got very expensive ones, things are going to be the same in the center. For the planets in the 12" you need something around 6mm or a Barlowed 2x to get the most of it on a very good night. I would maybe get the SVBony SV191 Zoom for an eyepiece that will cover a lot of needs without breaking the bank.

 

Check out some sketches (not DSO pictures) of some of the famous objects to have an idea what to expect. Take the scope somewhere with Bortle 3-4, it will show double of what you see right now in Bortle 6.

 

The splitting of double stars is a skill issue, you will have no problem with this once you get the skills up.

 

The 12" DOB is a very serious telescope which will show you the vast majority of amateur astronomy. Even if you looked through a 20", things are not going to be dramatically different... just somewhat bigger and brighter.

[JoeFaz]

Some other good double and multiple stars at this time of year include Struve 761, a triple star close to Sigma Orionis, h3945 (145 G Canis Majoris), a very colorful double star nicknamed the Winter Albeiro, Beta Monocerotis, which is perhaps the best triple star in the heavens, Almach (Gamma Andromedae), Eta Cassiopeiae, Iota Cancri, and Algieba (Gamma Leonis).
 

The following links lead to lists of binary and multiple stars:
 

https://www.astronom...t-double-stars/
 

http://www.skyandtel...h/double-stars/
 

https://www.astrolea...ectList2021.pdf
 

https://gardenastron...m/double-stars/

As far as double stars, Dave's given you some good links here, I'll just add a couple pieces of advice. As others have pointed out Sirius was a poor choice to start with (that's ok, now you know!).

 

-Start out with doubles with generous separations (the numbers followed by "). Also, start with pairs with fairly similar magnitudes, that aren't too faint. Both of those factors make them much easier to "split." After you've got the hang of it move on to progressively more challenging splits (closer separation and larger mag differences ("Δ magnitude"). Your scope is well capable of splitting sub-arc second pairs, you just need to develop the skill yourself first. It isn't rocket science or anything, it just takes some doing!

-Do a little research to learn what the position angle is. It will be very helpful in confirming your observations, especially once you move onto more challenging doubles. In short, the angle stars drift out of the FOV (west) is 270° and 90° counter-clockwise is 0°/360° (with your scope, a refractor would be different), or the opposite that you might expect. From there fill in the gaps and interpolate the approximate position angle you see compared to what is provided for the pair you think you're looking at. Remembering the 45° increments (45°, 135°, 225°, 315°) may be helpful too. Personally, I only expect to "eyeball" within 20° or so, but have gotten a bit more accurate over time).

 

If you end up finding that you enjoy observing doubles, Stelle Doppie will become an invaluable resource.

Edited by JoeFaz, 28 February 2025 - 08:57 AM.

[Russell Swan]

Ok, now I can definitely see the clips you guys are talking about. How in the world would I know how tight those are, I mean they are all the way in the bottom of the huge tube and from what I can see have no access from the back.

Don’t touch the clips unless you understand what you are doing and why you would do it. The last thing you want to do is mess with the mechanics of the scope right now, not knowing that the supposed problem resides there. You will only make things worse.
 

Question: Do stars look like little triangles rather than round at best focus? 

Edited by Russell Swan, 28 February 2025 - 09:26 AM.

[Mike Q]

Don’t touch the clips unless you understand what you are doing and why you would do it. The last thing you want to do is mess with the mechanics of the scope right now, not knowing that the supposed problem resides there. You will only make things worse.
 

Question: Do stars look like little triangles rather than round at best focus? 

This right here.  Don't mess with the clip, at least not yet.