Hello, new to the forums and astronomy! Have some newbie questions!

[Baggievann]

Hi everyone, as you guessed by the title I'm new on the forums so thought I'd say hi!

I'm new to astronomy but have always had a fascination with the stars and universe in general, but never the time or finances available to make a proper effort at getting into astronomy seriously! However, with it being christmas, my girlfriend and I are planning on getting a scope to do some observing and astrophotography!

I'm a pro terrestrial photographer by trade, so know my way around lenses and photography in general, but astrophotography appears to be a very complex and technical beast! I have not had much experience with long exposure photography as most of the stuff I shoot is wedding/fashion/editorial based, so my kit is essentially set up for portraiture, however I do have a 5dmkii and a very powerful computer at my disposal, so would like to try a few techniques out in astrophotography!

My dilemma is, as most people who are new here have, which telescope should I buy?!

I have a budget of around £400 to buy the basic scope and mount, then I will add to the kit as I go along and gain more experience of observing. I have narrowed my choice down to two scopes, both on an EQ5 mount.

The ubiquitous Skywatcher 200P...

Reflectors - Skywatcher Explorer 200P EQ5

And the Evostar 120.

Evostar - Skywatcher Evostar 120 OTA

My main interest is going to be deep space work, for which I think the newtonian is a better bet for the larger aperture, but then again you lose image definition and contrast over a refractor, but on the flip side you have more resolution with the larger aperture and hence can gather more light. Then of course there's a higher magnification on a newtonian, but do I really need it seeing as some DSO's are almost the size of the full moon?! But we end up back at aperture for collecting what little light there is?!!

It's all very confusing!

I plan on using the scope in conjuction with my 5dmkii and creating full frame HD1080p video, and stacking it in registax or similar at first, then I plan on moving onto long exposures and other techniques in future as my kit expands. I suppose the 65 thousand dollar question is, which scope will fulfill my needs better, and which will be more valuable for someone wanting to image DSO's, the aperture of a newtonian, or the image quality provided by a refractor?

I've probably made a butt-load of errors and mistakes so feel free to point them out, but hopefully someone can point me in the right direction!

Thanks in advance!

[Ags]

Welcome to the forum! I'm sure someone will be along with good advice soon... :-)

[brantuk]

Hi Baggie and welcome to the group

Sounds to me like you have all the pros and cons worked out for each scope. Not a lot to add other than to say most images I've seen tend to suggest a preponderance of refractors are used. However if you plan on any substantial observing then the larger aperture newts tend to be favoured. Most imagers usually have an observing set up as well.

Someone may be able to add something more - good luck with your eventual choice

[Bizibilder]

The Evostar, whilst an exellent telescope, is not really suitable for photography. Is is achromatic - partially colour corrected optics, where you would need Apochromatic - effectivly fully colour corrected ( a 120mm APO is around £1000!!).

May I make two suggestions to help you start: Firstly buy the book "Making Every Photon Count" by Steve Richards (£19.95 from FLO - see logo at the top of the page - usual disclaimer by the way!). Secondly it is the mount more than the telescope that is important in astro photography - so save your pennies for a decent mount - you could use your normal camera equipment on an astro mount to get yourself started.

[Astro_Baby]

I'd seriously recommend getting a copy of 'making every photon count' and reading it before you decide on scopes.

[dmahon]

You won't add to the mount, you'll sell it and get a better one. Same with the scope. If photography is the thing, spend the whole lot on the mount and get a scope later. Stick your camera on the mount. You need one that will track, and I'd get a HEQ5 (and I'd pay more than your budget for the syntrek version, that can be controlled by computer).

If for observing, you'll have to split your money between mount and scope, and a bit on eyepieces/accessories, so will suffer when you come to take pictures. The Skywatcher 200P on an EQ5 may actually be the best bet, but perhaps get the DS version instead if you also have an interest in photography - as you may otherwise struggle later when attaching your DSLR. You don't seem to be able to order that combination directly on the internet from FLO, so you may have to give FLO a call.

[Baggievann]

Thanks for the advice so far guys! I will get a copy of Making every photon count ordered ASAP! So out of the two scopes it appears as though the 200P/200P DS is the better bet... the only thing that scares me is the process of collimation on that scope! Is it worth buying a laser collimation tool to go with it at all?

I think I will start off observing to begin with to teach myself the stars and learn how to use the scope properly, I've heard theres an astronomy club not far from me so I will probably go down there to learn, and hopefully after 6 months I can swap the EQ5 for a sturdier mount with a synscan upgrade for more dedicated imaging!

Is the upgrade from the standard 200P to the DS version worth the extra money? I've gathered the DS has better focusing, but you can buy upgraded focussers anyway can't you? Are there any other discernable differences between the two?

Thanks!

Baggievann

[brantuk]

Collimation with a laser is as hard as changing a tyre on a car. Soon as you've done it correctly once, you never forget it.

A good quality collimator (imho) is a sound investment. I use the Hotech but there are others that people prefer

[Dave S]

I'd be careful if you intend to use the 5dmkii. It's a heavy beast and will not balance well on anything but the most heavy duty mount. Without some serious counterbalancing you will put a lot of strain on the drive motor(s).

Dave...

[ollypenrice]

I would forget the scope and get an HEQ5 to start with. The mount in imaging is fundamental and messing around with less than an HEQ5 Pro is going to spoil things for you. If you have good cameras and lenses, use those. The Petzval portrait lens was the pioneer design in astrophotography and is the system used in the best astrographic refractors today.

I love using my 85mm portrait lens, a humble Samyang, and I bet you have far better to try. Here is what it can do with a CCD behind it and this nebula is seriously faint.

Widefield images including mosaics and overlays. - ollypenrice's Photos

When using DSLRs for deep sky they really need to be de filtered and maybe re filtered to make them sensitive to Ha light. But maybe you have a body you could use for this?

Another thing to check out would be the Astrotrac mount which is a very accurate camera mount for astronomy. It can do unguided imaging out to reasonable focal lengths. One of my guests is a professional photographer too and this is what he is doing with stunning results.

All great fun.

Olly

[Sparrow]

Hi Baggie and welcome to the forum.

Your knowledge on photography will certainly be useful to you in Astro photography - at least you'll already be well aware of ISo's, F stops, optics etc so alot of the terminology will be very familiar to you. I'm a long time daytime photographer and more recently Astro photography. The Astro work is certainly a different animal. Signal to noise ratios become all important and this is where the basic concept of stacking mulitple images really comes in to play, to reduce noise. There is some overlap - framing the target, focus etc. The primary difficultly is taking long exposures of a predictably moving target (the night sky) This is where you'll begin to read about guiding and the need for two scopes and cameras. Initially there's nothing wrong with one scope and one camera, but this will restrict the length of your exposures which in turn will limit what you can actually image.

On the subject of scopes, it's horses for courses. Different targets demand different scopes. As you say it's the deep sky stuff that you want to image, then the newtonian can't be beaten for price and magnification. However, for larger targets, small refractors become the weapon of choice. At the moment I'm using an 8" newtonian for smaller objects such as planetary nebula and distant galaxies, and a 66mm refractor (apochromatic) for larger nebula. Ideally I also need a larger refractor like a 100 or 120mm which is on my wish list for next year.

My personal recommendation would be to concentrate on a decent mount as you first priority. This is the foundation on which you build your kit. I'm using the Celestron CG5-GT mount which I'm really happy with, but many users on here will recommend the Skywatcher mounts whcih are undoubtedly good. To start imaging nebula you could perhaps aim for a small apochromatic refractor - costing about £4-£500, plus mount and then perhaps add to it later with a cheaper refractor like the Skywatcher startravel which is fine for guiding purposes. The website for this forum's sponsors (First Light Optics) is well worth a visit to have a look at the various scopes available.

Regards

John