New User Questions!

[Likwid]

Hello everyone, long time lurker here. I have been researching a good first real telescope for quite a while now and a recent experience put that into overdrive. I was on vacation last week and I saw the Milky Way in person for the first time. It was breathtaking! It really makes you realize how small you are. Anyways, I have done quite a bit of research and there are a few things that are still a little unclear.

I want to focus mostly on DSO's and Astrophotography. Planets would be cool to see, but I don't want a rig just dedicated to that. There are more DSO's than planets (That I could observe) and I would get more use out of that. Now, I think I understand the technical aspects of getting images and I am good with my DSLR.

First, I am looking at the ZEQ25. I have done a LOT of research and decided that it would be the best EQ in my price range. I know that I will have to do long exposures, and I live in a red area on the light pollution map which will make that difficult or impossible. Is it worth getting an EQ over an Alt-Az if I can't use it for long exposures? I don't want to buy a Ferrari to go get Milk. I also plan on moving in a few years to a less light polluted area. Should I get something cheaper for now and upgrade later?

Second, should I be looking at a pre-built rig like the NexStar 6 for example? I know the mount should be about 80% of my budget and in this case, it is. It is also good that I can upgrade in the future and still use the mount, and with the scope I am looking at I can still use it for a guide scope. I could be wrong about not being able to do long exposures in heavy light pollution which would make this null, but would it be smarter to go with an Alt-Az that is prebuilt?

Third, I am looking at the Orion ST-80. As I said before, I like that I can use it as a guide scope if I want to upgrade in the future. From what I tell, I can't use it for planetary but it should work great for DSO's (Which is fine with me.) Is there another scope in that price range that would be better for me? I don't want to have to worry about collomation just yet, it would be overwhelming to have that on top of this already large learning curve.

I apologize in advance if anything has already been covered in any other forum posts. I have been researching a lot and these are the main questions I have up to this point. Thank you very much in advance, and I am sure I will come up with more in the future!

[Charic]

Welcome to the SGL.

Finding the Milky Way,  its very impressive, you'll remember that image for ages and more to come!
I tend to favour, and only have experience with visual observations using an 8" Newtonian reflector on a Dobsonian mount.
Its good for my needs, but something you still may want to consider one day, but  folk more experienced with the kit your surveying  at present, will offer some answers to your questions, based on their experience, and don't be afraid to ask more questions if you can't find the answers just now. 

 

[Likwid]

Thank you! I actually was looking at a kit with a Dobsonian mount a while ago. From what I read, a lot of people put them on upside down buckets and it didn't seem very stable to me but what do I know lol. The Milky Way absolutely changed me. I got a few good pics after I stared at it in wonder for about 15 minutes. I think I was even drooling at one point haha.

[Charic]

........some folk here use water butt stands, the type used to hold aloft  those plastic 200 litre  rain water butts, which raises the container slightly  allowing the  placement of a water carrier  to be filled from the base level spout?  As these butts can weigh in excess of 200 kilograms, their quite sturdy when it comes to supporting a Dobsonian telescope, some folk find them to low, if/when standing to observe, so need a suitable device to raise the scope, these base units, if chosen correctly, fit an 8" Dobsoninan quite well, but   I'm perfectly comfortable sat on a   drum stool, fully adjustable for my needs, and even though I own a 3-piece water but stand, its not something I have needed to use just yet. If Anything,  a simple wooden frame, just to keep the base of the scope of/above wet ground, but a simple mat works  just as well.

Take your time whilst choosing a telescope, there's no rush, the Stars will always be there, also, how about some wide-field low powered binoculars in the meantime, their low  power  reduces magnified handshake, then take another look at the Milky way?

[Putaendo Patrick]

Welcome!

Heavy light pollution is probably THE greatest enemy in observing and photographing DSOs. So unless you can escape to a darker site at weekends for example, I would have a careful rethink . There are of course, plenty of other types of target which will withstand all but the worst LP

How much experience do you have of astronomy in general? And how quickly do you want to get into astrophotography? It might be better to hold off for a while until you move to a darker area, and spend the meantime building skills in general visual observing.

Respecting the telescopes you mention, the Nexstar 6 is a very good set-up but not ideal for DSOs. The telescope is a Schmidt-Cassegrain design with a long focal length (1500mm) and slow focal ratio (f10) which would make it good for lunar and planetary observing and imaging with a CCD camera.

If you go with the Orion ST-80, I think you would probably want to upgrade the focuser quite quicky, and considering the added expense, there are probably better options. If you can spend a couple of hundred more, I would consider the Orion ED80 80mm f/7.5 Apo. Being an apochromatic (or semi-apo, depending on how you use terms!), it will substantially reduce fringing or C.A. The focal length is 600mm, compared to 400mm, which I think might be more useful. The focuser is better, and 2" compared to 1.25". Plus you could push up the magnifications for some planetary observing.

I don't personally know the specific iOptron mount you mention, but the specifications look interesting! In the long term, a good equatorial mount is essential for AP. If you delay on the photography, however, a short tube refractor would work nicely on a decent manual Alt-Az mount for visual.

A six, eight or ten inch reflector on a Dobsonian mount generally (I think always) rests directly on the ground or some low level flat base. Some smaller table-top Dobs can be used very effectively on a bucket! And, by the way, after a bit of practice collimation is not difficult, and certainly not the nightmare it is sometimes made out to be. For visual observing of DSOs large aperture is ideal - but only in dark skies I'm afraid!

 

[Likwid]

That makes much more sense Charic. I thought everyone was talking about little 5 gallon plastic buckets! That seems much more stable! And yeah, I know I have plenty of time. I just want to make sure I make the right decision when the time comes

Hello Patrick! I know a lot about the cosmos in general, but I don't know much about where things are. That's where the GoTo idea came into play. I have a copy of Turn Left at Orion that I am going to use to help starting to navigate. When I was a kid, i was really into everything and had a cheap department store telescope so it shouldn't take me much time to get back into the groove. That is very interesting with the Apo, I didn't know that it reduced Chromatic Aberration. It is one of the things that drives me nuts with normal photography. In normal photography, it is usually on straight edges. Is the C.A. due to the light from the stars? I guess almost like a sun flare on a smaller scale? I guess all the numbers are very confusing, and combined with all the different types of telescopes it makes for a huge headache trying to figure out what is the best fit! I understand the focal ratio from normal photography, and I understand focal length. It gets confusing again with the eyepieces and how they magnify as well as what focal length you would need for what application. Everything seems a bit backward from what you would think. You would think that you would need greater magnification for DSO's than planets because planets are closer and DSO's are much smaller in comparison because of the distance but that is not that case (That is how my brain sees it at least). I also figured that was the case with DSO's, I know a camera is much more sensitive than our eyes are. I just assumed there would be things that I could see still through the light pollution! Also, that ED80 was on my radar. I saw a picture of a nebula that someone took with it and it was amazing!

Thank you both for the informative replies! It certainly points me in the right direction. There are so many things that I don't even know that I need to research, it's going to be an interesting road lol.

[beka]

Hi Likwid, well done on your research. DSO Astrophotography under light polluted skies means long exposure narrow band with dedicated astrophotography CCD cameras. I have no experience with this but I am not sure you want to go there right away. If you do the mount you mentioned together with a refractor like the one suggested by Putaendo should work. You should then expect to spend another pile of cash on a CCD camera, filters, guiders and so on. I think the astrophotography guys  should share their experience but my opinion would be that you should do some visual, probably with a dob, to get more familiar with the night sky and astronomy gear, and to discover your level of passion for the hobby before you plunge headlong into hardcore astrophotograpy. Good luck!

[CraigT82]

Hi Likwid, I'm no astrophotographer but ive been a visual observer for a few years and have just veered in planetary imaging which I'm getting hooked on fast! Although that's quite ironic as most of the planets are going to be very low in the sky in the next few years and not ideal for imaging.  Nevertheless if you have a planetary imaging rig then you have a decent rig for imaging the smaller/brighter DSO (planetary nebula and globs).

A lot of DSOs are actually huge and if you were able to see them in the sky you'd be amazed, for example M31 the Andromeda Galaxy would appear 3 times the size of the full moon if you could see it's full extents naked eye.

like yourself I live in a heavy light polluted area and this is why ice gotten into planetary photography. I will have a go at DSO photography sometime but not for a few years at least. 

DSO photography of nebulae is possible under light polluted skies but as mentioned by beka above it involves shooting though narrow band filters, which block out all light apart from very specific wavelengths related to the emission lines of nebulae (Ha, Oiii, Sii etc...). This type of photography requires a mono sensor (not DSLR) and a very good mount with very good guiding as long exposures are required. The filters are expensive and so are the mono CCD cameras required. 

I think if you are sure you want to get into astrophotography you would be well advised to buy a decent EQ mount (ZEQ25 or HEQ5 minimum) couple that with a small ED or Apo refractor of about 66-80mm aperture (ED80 by orion or Skywatcher are popular). You can then use your DSLR with a good light pollution filter to take reasonably long exposures of the brighter DSOs (Orion neb for example), and would be a good way to practice and really get to grips with all that's involved (setup, alignmentcapturing, processing) .That set up would also be portable for trips to dark skies.

If you did decide to delve deeper into AP, you could add guiding, mono CCD, and filters and get really stuck in! 

[laudropb]

Hello and a warm welcome to the SGL. I am purely a visual observer and use an 8 inch DOB. I have looked into astrophotography and with out doubt the most useful source of information I found was the book Making Every Photon Count. This was written by a member of this forum and is considered by many as the definitive text on the subject. It is available from the site sponsors FLO and they do ship to the USA.

[MattJenko]

You certainly have come to a good place for advice. Here is some from me.

DSO photography is pretty hard. There is no getting away from that. Because of this, when starting you want to make things as easy as possible for yourself. No-one has mentioned it yet, but the book 'Making Every Photon Count' is an extremely good place to start.

CA is from the light diffraction when passing through the lens in the telescope itself. The ST scope bends the different wavelengths differently, do Blue does not focus at the same point as Red. The ED scopes do a better job at getting this focus correct, so CA is reduced. You don't get CA from reflector type systems, just other aberrations inherent in their designs. A small refractor on an EQ is a very good place to think about starting AP.

[billyharris72]

That mount certainly looks interesting. It's not cheap (though it's certainly not expensive as AP mounts go), so I'd only consider it if you definitely plan on upgrading the scope at some point. For an ST80 or similar you can actually get away with an EQ5 for exposures of (definitely) 1 or (maybe) 2 minutes, which might be as much as you can manage anyway in a light polluted area (with a light pollution filter). You could maybe do more with guiding, though there is a lot of backlash on the drives on that mount.

If you are in doubt as to whether you would upgrade the scope maybe look at a second hand HEQ5 or similar and spend some extra cash on the tube. The ST80 suffers chromatic aberration and shows a lot of field curvature, in addition to the focuser issues already mentioned. There also is no field flattener that I am aware of. It's usable, but in my experience even an £85 Sigma 70-300mm zoom at 300mm outperforms the ST80, while being pretty poor in itself. If you could use the saving on the mount to fund an ED or even a small Apo on an HEQ5 (which will handle it easily) you'll likely get better results.

As to the question of whether to go for an EQ mount if you're going to do visual, I don't think it's necessarily a bad idea. Visual setup of an EQ mount is very quick and once you get used to moving it around the axes it does have some advantages (though these are more important for planetary viewing). That said, you might be better starting with a Dob, even if you do plan eventually going down the AP route - cheap, easy to use and with much more light grasp. The ST80 and it's ilk are nice wide field scopes, but definitely not good for visual DSO observation, especialy in light polluted areas.

You say in the post that this will be your first "real" scope. What do you have already? It may seem too low down the pecking order but the Heritage 130p is a great intro scope (optically miles better than any short tube achromat) and can be picked up for not much more than £100. And as it's a mini-Dob that includes the mount.

 

 

[Likwid]

Wow, thank you all for the great replies! I do not have a scope currently, but when I was in high school I had a really cheap telescope that I used to spend hours with just studying the moon. That also makes A LOT of sense with the size of the galaxies, it puts things into perspective for me. Making Every Photon Count is one of the next ones on my book buying list, I actually might grab it now for some good reading! I was hoping just to get the brighter nebulae and galaxies for now, I don't want to invest a ton of money just yet. I actually didn't think that a rig that did what I wanted it to do, could also do planets well! That would make for a lot of different things to explore. So I should look for an APO Refractor to do Planets, Bright Galaxies/Nebulae and start with Astrophotography? I guess I have to save up a couple extra bucks and get an ED80 if it can handle everything that I wanted to do! Thank you very much for the great advice everyone! I really appreciate it! Things are starting to make a little more sense

[Likwid]

Actually, another thing that I just thought of with the mention of the 300mm lens... Would I be able to get anything decent with, say a 300mm telephoto lens and a sturdy tripod for now to get a better feel for the photography aspect? I know a lot of sky images I have taken (The Milky Way in my signature was taken by me last week) have a lot of noise and I am still trying to get that aspect under control as well as the post processing with stacking and light pollution control. I know I couldn't do any long exposures or anything, but would starting with the moon, modifying my old Rebel XS to remove the IR Filter and trying to get double stars and constellations be a good starting point to move onto the investment of the scope that I would need when I am ready? I could also learn the sky much better that way and have a better idea of what is possible to capture.

[graemlourens]

Hi and Welcome!

I like that you already made a lot of though processes, that i missed when i started (and i wasted a lot of money)
I think one of the basic questions will be if you have the time to drive to a darker place. Its time consuming and you'll be sleepy the next day  But we're a crazy bunch here so thats not impossible!

I too went pretty much straight to Astrophotography, and ended up deciding on the very well established ED80, as its a great scope, and has tons of accessories, and you'll not have problems adding stuff to it when you continue. If you want to see what that small ED80 can do, click my flickr link in the footer. I always thought you need a crazy expensive scope... you really don't. The mount is a different issue though, and there it gets expensive :/

But for starters you could easily put an ED80 on a cheap alt/az mount for dabbing around the hobby and then later on go EQ!

Kind regards, Graem

[Likwid]

Awesome, thank you for the advice! I think I am going to start out just using my normal camera gear to learn to control the noise and everything in post processing. Once I know the sky a little better, I'm going to go with the ZEQ25/ED80 combo! It seems like a solid combination, thank you again for all the great replies!

[tripod tipper]

Hi likwid,

Welcome the SGL. I would like to describe my intro to astronomy. I used to be in the hobby till I became married and had children. I am a newbie in the SGL just getting back into it. First, I would advise you in a good way of those in the SGL, they know what their talking about.

My own testimony...

The first telescope I had was a 101.6 mm or a 4" reflector DOB. I looked at all I could find without even knowing about charts. I discovered within myself a fascination with the planets and stars even nebulas, still not knowing anything about charts or even the likeness there of, I proceeded then to a 152.4mm or also known as a 6" reflector, after that I went to a 203mm, 8" DOB. All these were offered as kits at that time which had all the hardware, I just had to get the tube and the plans for the stand, (me and my friends built them back in 1979). No astrophotography within any armature reach at that time. If you can use a scope from someone who is willing, you might find out if you have the fever or a passing fling. Personally from reading this thread, I think you might be smitten already with the bug. In my opinion, (which is just, an opinion), look and see what you can. If you like what you see then go for it without spending a fortune. The reward is amazing to say the least. You can grow from there!

Dennis

 

[Dave Lloyd]

Hi Likwid, welcome.

[Alan64]

On 8/4/2016 at 08:09, Likwid said:

Awesome, thank you for the advice! I think I am going to start out just using my normal camera gear to learn to control the noise and everything in post processing. Once I know the sky a little better, I'm going to go with the ZEQ25/ED80 combo! It seems like a solid combination, thank you again for all the great replies!

For deep-sky imaging, a maximum of f/6 and faster(f/5-f/4) is best...

https://www.astronomics.com/astro-tech-at72ed-72mm-refractor-telescope-black_p18263.aspx

https://www.astronomics.com/astro-tech-at72ed-72mm-refractor-telescope-white-gray_p18452.aspx

I'd get on the wait list for either one asap.

The Orion ED80 is an f/7.5, and a bit too slow for deep-sky imaging.