spacedobsonian

You know, people look at the Jupiter or the Andromeda galaxy and say "Is that it?" I think people don't think about what they are looking, so I would just say that just think about what you are seeing, Jupiter, a planet larger than any, floating 750 million km from earth, with its great red spot 4x the size of earth. It just gives a sense of grandeur while observing it and that's the main reason I enjoy this hobby! 

I would recommend trying it out the next time you observe anything!

I am thinking of starting to dip my toes into astrophotography, I have little budget for a camera so I went to Orion and found two cameras for under 175£, I want to shoot simple planetary shots and some deep space, the telescope I might use this on is a 70mm f/10 refractor, or a 100/114mm reflector.

I don't want world class images, but just want a few simple pics, so here are the cameras that I found:

https://www.telescope.com/Orion/Orion-StarShoot-3mp-Solar-System-V-Imaging-Camera/rc/2160/p/130983.uts?sortByColumnName=SortByPriceAscending

And:

https://www.telescope.com/Orion/Orion-StarShoot-Mini-12mp-Color-Imaging-Camera/rc/2160/p/134986.uts?sortByColumnName=SortByPriceAscending 

The first one seems good enough but the second one seems to be really good, just that there are no reviews of it on the Orion site.

Any and all advice is appreciated!

11 minutes ago, Siegfried1969 said:

the contrast booster works very good on the moon and Mars.

Going really off topic! Does it work on Jupiter and if not which simple (colour or any) filter will work for planetary?

Now, Astrophotography in Mobile has advanced a lot, you can take the same 200 photos automatically, all of semi long exposures (depends on the smartphone, mine has 40 seconds of exposures), but you can't stack them! In my opinion, a basic software like Snapseed but better, for astrophotography, and for beginners with easy UI and some stacking capability!

That would be astrophotography heaven! (Atleast for beginners!!)

4 hours ago, AstroMuni said:

One tool that would greatly help a beginner is helping choose a telescope. If you see the forum, its filled with queries on what sort of scope should I buy. The basic questions asked by experienced folk are the same everytime - eg. visual or AP, interested in planets or DSO etc. While a tool may not be able to give an exact scope, it could be used to narrow the choices into broad set of scopes like Dobs, Mak, Frac giving a range of apertures. If a budget can be built into the tool then brilliant.

Very true! 

Just now, spacedobsonian said:

A bit off-topic but they made a heritage 114p?

I mean Skywatcher 

6 minutes ago, wulfrun said:

I have a Heritage 114P, it has a collimatable secondary but the primary is fixed. I've tweaked the primary as per @Peter Drew's method above and made sure the secondary is correct. I've checked it now and then and it's not needed any adjustment since, so I don't think the fixed primary is an issue. Probably helps that the mirror is relatively small and lightweight.

A bit off-topic but they made a heritage 114p?

2 hours ago, Carbon Brush said:

Can you provide links to the actual scopes?

For example:

https://www.firstlightoptics.com/beginner-telescopes/ursa-major-102mm-tabletop-dobsonian-telescope.html

And 

https://www.firstlightoptics.com/heritage/skywatcher-heritage-100p-tabletop-dobsonian.html

2 hours ago, Steve Ward said:

Both are 'collimatable' ... 

How?

1 hour ago, cajen2 said:

I believe it's this one:

https://www.firstlightoptics.com/beginner-telescopes/ursa-major-102mm-tabletop-dobsonian-telescope.html

and it's being compared to a SW tabletop like this:

https://www.firstlightoptics.com/heritage/skywatcher-heritage-100p-tabletop-dobsonian.html

 

That's were I got the original idea for this post!

1 hour ago, wesdon1 said:

Do you mean one 'scope is broken, so can't be collimated? To my knowledge, all Dob's-i.e. Newtonian Reflectors, are collimatible? ( Remember the name "Dob or Dobsonian" only refers to the way the telescope is mounted )

No, some scopes like the Skywatcher 130 starquest can't be collimated!

If you had to buy a small reflector dob (<6 inches) would you pay £20 more for a parabolical mirror BUT lose the ability to collimate?

Would you buy the cheaper, spherical mirror, collimatable reflector dob or a £20 more expensive, parabolic mirror, not collimatable reflector dob?

10 hours ago, Mike Q said:

So here is a question.  What kind of vehicle are you going to be transported this in or on.  For me I can transport my 16 on a whim, but i have a fullsized truck which makes it simple.  So the size of the scope will need to be in direct proportion to your vehicle.  So tell us.... What kind of vehicle will you be using 

It will be transported on a car but I also want it to be very compact because it will be travelling! 

14 hours ago, PeterStudz said:

Yes, and thank you. I got it for free in April 2021 from a member on here. It came without a base and had simply been neglected. Now, at that time I’d only been in the hobby for 4 months so was very much a beginner. But it is well put together  and super easy to work on, take apart, and put back together again. I’ve attached some pictures.

The 200p has been and still is fantastic and I’ve had so much fun with it. My daughter too who also enjoys astronomy. In fact I’m just about to put it out now for some views of Mars, Jupiter, the moon and whatever else I can see. 

Pretty nice dob!  

15 hours ago, fwm891 said:

I take it you just looked at the poorer review and ignored the good ones. Pretty much all new scopes will require some adjustments. They're built to a price so final adjustments may only be mediocre at best.

Take note of Mandy's reply a s/h 150 or 200mm with stock eyepieces will be much better than a 100mm with slightly better eyepieces.

I actually read all reviews but I just pointed the ones that were a bit negative! 

2 minutes ago, Mandy D said:

I totally agree with @fwm891. I picked up my 200P Dob for £200. If you can transport and handle a scope of this size, it will certainly perform better on the deep sky and works well on the Moon, too. For the planets, you can image Jupiter and Saturn, but would be better adding the Barlow. I've had some nice views of planets in my 250PX and these should show up nicely in the 200P.

I agree that the eyepieces included with these scopes are not great, but the 25 mm works quite well, but I don't like the 10 mm. Get the scope first and use whatever eyepieces it comes with. You can always get better ones later. Be warned that a second-hand reflector may require collimating before you can use it, but that is something you need to learn anyway.

Hey @Mandy D please check my reply to @fwm891

Just now, fwm891 said:

Personaly I'd forget the accessories to start with go for SW 130 https://www.firstlightoptics.com/dobsonians/skywatcher-heritage-130p-flextube.html

and a £4 collimation cap (still under your budget). Don't forget the s/h market you can probably pick up a 150 sized dob within your budget. Then add eyepieces etc later when you have a better idea about what you NEED.

I was originally going to go with the SW 130 but I read that the mount is really sloppy and etc, etc

Here's a review:

"I can complain a bit about the focuser. I needed to put some Teflon tape on the threads since there was too much slop in the movement. The tape made it stiffer and you can keep putting on more layers of tape to make it however stiff you like (and remove it easily too)"

"Now the only major complaint I have: the secondary mirror. First of all, the way it attaches to the tube is a bit finicky and it came very loose so that the secondary mirror rotated way too easily. This needed to be tightened with a small pair of pliers (there is a locking nut next to where the metal rod attaches to the inside of the tube). In a quality control issue, my secondary came installed rotated by 180 degrees from the correct orientation."

"I realised that the secondary mirror that came with the telescope was quite a bit oversized. The specs on the SkyWatcher website say that the secondary is 34.5mm. In fact, the one I got was 40mm (minor axis diameter). This represents a 31% central obstruction, which is quite high, even for a fast Newtonian (the secondary mirror gets smaller as the F number increases). In fact, the maximum size of the secondary mirror holder is 35mm in diameter and a quick calculation shows that for most objects (such a looking at the moon), a 30mm mirror is large enough. So I ordered a new 35mm diagonal mirror from Orion Optics UK and with the "Picture Hanging Strips" it was then very easy to swap the secondary mirror."

All of the above paragraphs are from a single review.

On 28/12/2022 at 16:12, ollypenrice said:

The curve on a Schmidt plate is interesting. Bernhard Schmidt, who blew off his arm as a child chemistry experimenter, claimed that he could get comatose drunk, pass out for a long time and then come round with the solution he'd been looking for. He had conceived of the curve required in principle on a lens to reduce coma on a reflector but it was, apparently, impossible to grind. Then, perhaps after one of his bibulous escapades, he went and asked Walter Baader about the physics that would apply to the distortion of a glass blank if it were placed over the top of a cylinder from which the air could be evacuated.  Baader (one of the few people whom Schmidt liked) said he didn't know but pointed him to the right book. Schmidt's hunch proved to be correct: if you put the blank over the top of a cyclinder, paritally evacuate the air beneath it and then grind the vacuum-distorted blank flat again, it will, when released, have the desired shape. This is still how they are made. Since the primary of an SCT is spherical and the corrector can be made in this relatively simple way, they are an attractive commercial proposition.

Olly

I was searching for a good portable dob and I found 2, but can't decide which one to take..... It's pretty much a dob dilemma 

First contender:

Skywatcher Heritage 100mm dob:

https://www.firstlightoptics.com/heritage/skywatcher-heritage-100p-tabletop-dobsonian.html

Second contender:

Ursa Major 102mm dob:

https://www.firstlightoptics.com/beginner-telescopes/ursa-major-102mm-tabletop-dobsonian-telescope.html

Now, I can buy 3 accesories which each of these scope and they are:

Astro Essentials Plossl Eyepiece:

https://www.firstlightoptics.com/astro-essentials-eyepieces/astro-essentials-super-plossl-eyepiece.html

Astro Essentials 2x Barlow:

https://www.firstlightoptics.com/barlow-eyepieces/astro-essentials-125-2x-barlow-with-t-thread.html

Skywatcher Planetary eyepiece:

https://www.firstlightoptics.com/skywatcher-eyepieces/skywatcher-uwa-planetary-eyepieces.html

Now, the real dilemma is that the Ursa Major dob (will refer to this dob as UM dob) has a spherical mirror BUT it has these great Astro Essentials Plossls 

The Skywatcher dob (will refer to it as SW dob) has a parabolic mirror BUT it has these not-so-great eyepieces. 

From the price point the SW dob is better than the UM dob, so which one do I choose??

(P.S I am going to do a bit of serious work with the dob that I will buy, UM or SW, for eg. The Moon, Jupiter, Saturn, Orion nebula and Andromeda Galaxy AND I know that small dobs aren't good for deep space work and planetary work)

(P.P.S My price budget is 200£)

On 31/12/2022 at 19:39, Cosmic Geoff said:

I think you will find that trying to do any astrophotography with this mount is a very instructive experience. 🤣

You may be shopping for a more substantial mount very soon.😀

Yes, and I feel I may go down the rabbit hole of astrophotography 😆

On 29/12/2022 at 17:15, Ricochet said:

Personally, I think that you should concentrate on choosing the scope that you want rather than thinking of which accessories you can also buy. Accessories tend to be cheaper and so it is much easier for you to save up again in the future for an accessory than it is to save up again for a whole new scope because you didn't buy the one you really wanted to save money now. 

The good thing about dobsonians is that you tend to get a very stable base for a relatively cheap price. However, with these table top dobs you need something stable to put them on at your observing location so the eyepiece is raised to a reasonable height. If you are going out in your garden or to a local park where there are nice sturdy tables you'll be fine, but in a featureless field or on the side of a hill you will probably want a tripod.

I would prefer either of these to the first option due to the increased aperture. Particularly when observing DSOs, aperture is king and jumping from 102 to 130mm is a significant jump. If I was looking to buy myself a small Newtonian today, I would probably be looking at a 130mm scope just for that extra bit of light grasp over the smaller options. Of the two I think I would prefer the f5 parabolic scope but I do not know for sure how the two mounts compare. I think they are pretty similar but I notice that the 130p on EQ2 is the more expensive choice.

@Chris did a couple of videos on the Starquest 130p so I would suggest watching those and seeing what he thought of it:

Starquest 130p First Impressions

Starquest 130p Review

I don't really like this suggestion and it is mostly because of the tripod. I don't think that tripod looks anywhere near stable enough for astronomy and with any alt-az head where the telescope is mounted above the pivot, rather than to the side of it, there is a tendency for the telescope to drift upwards as the head is unable to hold the weight without extreme tightening. Aside from perhaps being easier to store and transport I don't see what there is to gain over the Startravel 80 AZ3 bundle which I suspect would be much better for astronomical observations, especially with the slow motion controls that should allow you to track without loosening the axis tightness.

However, there are a couple of other refractor options within your budget, namely the Evostar 90 on either AZ3 or EQ2 mounts:

Evostar 90 AZ3

Evostar 90 EQ2

The Evostar 90 has a little bit more aperture than the 80, but most importantly it has double the focal ratio, so chromatic aberration will be greatly reduced making it a superior scope on lunar and planetary targets. I think I would go for a Evostar 90 EQ2 over the ST80 if it were my choice.

If you prefer DSO targets then there are a couple more refractor options slightly over your budget:

Evostar 90/660 Pronto

Startravel 102 AZ3

The first will give better correction than the ST80 and a wider field of view than the 90/900 Evostar.

The ST102 will give a good jump in light gathering over the ST80 for better DSO performance. However, I think the 130p will probably be better for both DSOs and planetary.

On 29/12/2022 at 21:47, jjohnson3803 said:

I'd go with an 80mm to 90mm achromatic refractor.  They're inexpensive, have a small form factor if you keep the f-ratio low, are easy to transport if you go to a dark site or on vacation, don't require a king-hell mount, and seem to hold good resale value.

True, they have some chromatic aberration, but mine - 50mm, 80mm, 120mm - all do an ok job on the planets at lower power and the moon at moderate power.  CA doesn't much matter IMO on deep sky.

Full disclosure - I did buy 72mm and 102mm ED doublets for lunar observing and double stars, but they each cost 4X to 5X as much as my achros.

 

Thanks for the replies,  and I have decided to go with Sky-Watcher Explorer 130mm EQ-2 because it has aperture and has a EQ-2 mount which with a single speed drive installed will let me have some basic astrophotography and astronomy observing! 

Thanks again for the suggestions

(P.S Mods close this topic, because my problem has been solved!) 

So, I have a budget of about 215 quids and here are some combinations I am considering for a beginner scope:

Ursa Major 102mm set:

Ursa Major 102mm dobsonian:

https://www.firstlightoptics.com/beginner-telescopes/ursa-major-102mm-tabletop-dobsonian-telescope.html

Astro essentials 2x Barlow:

https://www.firstlightoptics.com/barlow-eyepieces/astro-essentials-125-2x-barlow-with-t-thread.html

Turn left at Orion:

https://www.firstlightoptics.com/books/turn-left-at-orion-book.html

David Chandler's Large Planisphere:

https://www.firstlightoptics.com/books/david-chandler-night-sky-planisphere.html

Astro Essentials 1.25" ND96-0.6 Filter:

https://www.firstlightoptics.com/moon-neutral-density-filters/astro-essentials-125-nd96-0-6-filter.html

Sky-Watcher StarQuest-130P f/5 Parabolic Newtonian Reflector set:

Sky-Watcher StarQuest-130P f/5 Parabolic Newtonian Reflector (Only a telescope, no accesories for this one because the budget is tight!) : 

https://www.firstlightoptics.com/sky-watcher-starquest/sky-watcher-starquest-130p-f5-parabolic-newtonian-reflector-telescope.html

Sky-Watcher Explorer 130 (EQ-2) set:

Skywatcher Explorer 130 (EQ-2):

https://www.firstlightoptics.com/reflectors/skywatcher-explorer-130.html

Turn left at Orion:

https://www.firstlightoptics.com/books/turn-left-at-orion-book.html

Sky-Watcher Startravel 80 set:

Sky-Watcher Startravel 80 OTA:

https://www.firstlightoptics.com/startravel/skywatcher-startravel-80-ota.html

Tripod:

https://www.firstlightoptics.com/tripods/fotomate-vt-6006-heavy-duty-2-way-tripod.html

Astro Essentials 1.25" #8 Light Yellow Filter (For CA reduction):

https://www.firstlightoptics.com/visual-oberving-rgb-filter-sets/astro-essentials-125-wratten-8-light-yellow-filter.html

David Chandler's Large Planisphere:

https://www.firstlightoptics.com/books/david-chandler-night-sky-planisphere.html

(P.S If you have any suggestions please also include them!)

(P.P.S I haven't included the Skywatcher 130mm folding dob because it has some issues)

3 hours ago, teoria_del_big_bang said:

A very warm welcome to SGL.
Do not worry about Grammar, mine isn't the best and I have no excuse, its my first language (well if I am honest my oly language) 🙂 

I have worked several times in India and had some great trips there, where abouts in India are you ?
Are the skies very dark ?

Steve

It depends! I live in a semi-urban area so there is a bit of light pollution,  but we also got the first dark sky reserve which I am planning to go. Some places like Kazakh have pristine skies,  but mine do not

Hi everyone,  I am from India so please excuse my grammar mistakes / spellings. I began with a beginner 70mm f10 refractor and still currently have only one telescope, the 70mm! It will be fun with talking with you all!

Starry Night  🌃

Spacedob