Complete and total newbie acquired a Celestron C100 (15 years old or more).

[Lindsayanng]

Basically the title says it all.. My husband and I have kind of been obsessed with the new series on the science channel about the universe. We have been using a pair of binoculars and a small toy telescope (about same power as binoculars) that I got when I was about 11 (i'm 29 now) ..

So we were talking about a telescope but we knew that a solid one was WAY out of our price range when my father in law reminded my husband that he had bought him one when he was younger and it was sitting in the attic.

It's a beautiful C100 (not something a normal person would buy a kid) but I have NO IDEA where to start.

I have a basic understanding of the night sky as I can see it from my steps, but light pollution has made that relatively nothing.

I'd love to learn more about how to use the sky charts and general little simply but cool things to find to get me started.

I am someone who loves to learn, so I feel like this type of hobby could be really exciting for me. I am not all about the flashy stuff.

p.s. - i have read through this little article already as well as a few of the beginner sticky threads:

Sky Publishing - How to Start Right in Astronomy

Here is the telescope:

[John]

Hi and welcome to the forum !

Lucky you - that's a classic 1980's Celestron refractor made for them by Vixen in Japan. I've got an old Celestron catalogue with a piccy of one but I've never seen one for real, as it were.

Assuming the main lens is clean and clear (don't touch it though !) you need to make sure that the small finder scope is pointing exactly where the main scope is - you can do this in daylight by looking at a distant treetop / church spire etc.

I can see that it has a 90 degree diagonal prism which is helpful. What eyepieces are supplied with the scope ?.

They are probably the smaller 0.965" type which have been replaced these days by 1.25" but if you have some to go on with that will help.

[Lindsayanng]

I don't know 100% for sure but I am going to guess that the eyepiece is whatever it came with at that time. My father in law said he had another eye piece but couldn't find it.. I will verify for sure when I get back out to the car to eventually bring it home (at work right now).

I had a look at the lens at the end and there was a light scratch and some dust, but my husband is a photographer and has a LOT of really 'hi tech' cleaning stuff for lenses.. Should I assume that stuff for high end L lenses for a DSLRs is the same stuff you would use to clean a telescope lens?

Before we moved it I was able to focus it on the top of a tree but then we had to disassemble it, put it in the car, and drive it home.. I would assume that I would need to re-calibrate it then??

Also.. I am dying to know.. How much can I actually see with this thing? When I look at the sky charts it seems that they rate things based on difficulty and power of the tools used by the sky watcher.. Is this a higher powered "consumer" model? Or a medium one?

I really REALLY want to look at galaxies and nebula and .. well.. cool ****

[John]

With some care, your husbands lens cleaning gear should be OK but don't overdo it - a bit of dust is not going to affect the image. Nor should the scratch but it's a shame it's there.

Refractors (lens at the top end scopes !) are pretty stable so it should not need collimation / calibration but the finder will need re-aligning with the main scope - it's easy really - there are 3 lock screws at one end to tilt the finder slightly in it's mount - the object in the main scope view needs to be right on the cross hairs of the finder scope.

The scope is a nice 4" scope which will show good views of the moon, the planets, binary stars and the brighter deep sky objects. When it comes to galaxies and nebula, with one or two exceptions, 4" is not a large aperture scope so you will not see them as more than faint fuzzy patches of light. Fascinating none the less.

Get yourself a good guide to the night sky like "Turn Left at Orion" as you will need to find where in the sky these interesting objects are so that you can then track them down with your scope.

The freeware planetarium software "Stellarium" is well recommended as well. Google it to find the home page.

I think you will need to find one or two more eyepieces for it and that might be the tricky bit as, assuming it uses the smallest type as these older scopes used to, they can't be bought new and are quite hard to find used.

You may be able to convert it to take 1.25" eyepieces which would make life a lot easier for you.

[Lindsayanng]

Well my husband couldn't wait so he pulled it out of the car and brought it in.. The eyepiece is definitely 1.25.. We were able to focus on the tops of trees and stuff..

I am really very interested in seeing what we can see.. I did print out a sky map called "The Evening Sky Map" which says it is free each month. I remember from my "obsessed with outer space" years as a kid on how to read them.. heck, I even had a night light that would illuminate my room with each of the season's sky configurations!!!

[Lindsayanng]

Ohh and I have one more question.. Is there a place where I can go to see photos of "things" take with a telescope like mine?? I'd just like to know what I am kind of looking for.

[John]

Photos will be very misleading as the CCD's used for imaging capture more detail and colour than our eyes can see on everything apart from the Moon.

Have a look at some of the sketches in that section of the forum - they will be a more accurate guide. One of the biggest issues with newcomers to observing is disappointment that the visual views don't match the images you see.

The diameter of the chrome barrel eyepiece is the fitting size (1.25" or 0.965" or even 2" ). The focal length of the eyepiece should be marked on it (eg: 25mm, 20mm, 10mm etc). You divide the focal length of the scope (1000mm in your case) by the focal length of the eyepiece to get the magnification that is produced by that combination. Most observers use 3-5 eyepieces to get a range of magnifications from low (say around 30x) to high (say around 180x) powers. It's like gears in a car - you need a few to make the thing useful !.

[Lindsayanng]

Well being that my husband is a photographer, he is definitely interested in taking pictures with this telescope as well.. We plan on eventually buying some stuff to make that happen if we can't rig something together with the camera stand that he has..

Now to the magnification.. The focal length of the eyepiece is 25mm so it would be 1000mm/25mm = 40x magnification? I don't know exactly what that means though..

[andrew63]

Hi, welcome and good luck! Thats a very fine telescope - Celestron certainly don't make them like that any more!

andrew

[Lindsayanng]

Thanks Andrew!!

I'm sure you will be seeing a lot of me. When I get into something i REALLY get into it.. and I love active online communities like this one!

[John]

....Now to the magnification.. The focal length of the eyepiece is 25mm so it would be 1000mm/25mm = 40x magnification? I don't know exactly what that means though..

40x is a useful low / lowish power for viewing star clusters and other deep sky objects (galaxies, nebulae etc). To get the full used out of the scope you will want a medium power eyepiece (say a 12.5mm = 80x) and a higher power one too (say a 6mm - 166x). You may have an additional lens called a barlow lens. These lenses are used with an eyepiece and double the magnification given (it it's a 2x barlow) which can avoid the need for another eyepiece.

[Lindsayanng]

Ohh great!! Thanks for the tips! I will definitely look into "souping up" my telescope now that I know what kinds of things to look for.

I am going to play around with it on the next clear night (SOOOO disappointed that its very cloudy tonight) and see where I stand on my ability to find things.. Then from there I will look into adding new eye pieces.

I am not adverse to putting money into this, especially since the telescope was free for me.

On another note - what kind of thing would I need to hook a canon 5D or 7D to it?? From the pics I saw it didn't seem like my telescope would allow for it..

[hes not well again]

Hi Lindsayang, you can buy an adapting ring that will allow you to hook up a camera. It is used without any lens as the scope becomes it lens. Also find the darkest site you can for observing to get the best from your scope. My favourite is the orion nebula as its easy to find. [in the sword of orion]. Happy viewing

[Lindsayanng]

I figured that the telescope would be come the lens, but if that is the case, and there is no eyepiece to look through because the camera is attached, how do you really know what you are looking at?? Do you look at the camera LCD screen or through the camera view finder to see?? Or do you tether to a laptop?

My husband and I definitely plan on taking some night time road trips to dark areas.. From what I have read, though, there aren't too many of those places left.

We walked out to our beach thinking it would be nice and dark there, but it was insanely bright - which literally made me angry.. Like.. REALLY angry. It's such a useless pollution.. light pollution. We had gotten hit bad by hurrican irene and our town (and most surrounding) had absolutely no power for over a week and the sky was AMAZING! We didn't have anything but our own eyes, but we ate outside every night and stared at the sky.

[hes not well again]

If your camera has a screen then yes, use that. If it an SLR camera then use the veiwfinder. In the village in wales where my mother lives they actually turn the street lights off because the council has run out of money!

[southernman]

Have fun with your new scope. I have a similar refractor (Celestron C102-HD) mounted on a CG-4 mount. They are a good scope that work very well on the moon and planets. They also show some of the brighter deep sky objects as well.

[glowjet]

I have no wish to burst your enthusiasm bubble and you have a very nice quality scope, but I am afraid you will be limited as to what you can photograph, as only short exposures can be used on bright subjects like the Moon, the problem is going to be your mount which is what they call Alt/az, movement up down and from side to side, very nice for visual use, but for camera-work you would need to remount the scope on what is termed a GEM ( German equatorial mount ) which has the ability to track the movement of the stars, the mount will also have to be motor driven on its major axis to enable long exposures to be taken, you have a rather steep learning curve ahead of you, but as your husband is already an established photographer you will be able to experiment with this aspect and you will no doubt have some rewarding results, but as time goes by you will come to appreciate that there are limitations to what can be achieved

[rwilkey]

Great scope, I have the later version and it is good for visual use. Good luck with the photography!

[yeoboy]

I got a Celestron C80 ED and it came with a 25mm ep which gave me x24, I got an 8mm to provide enough power to see Jupiters bands (just),As a newbe myself I found the field of view important or you have to fiddle around with the mount to retain the image,I am awaiting a 5mm ep to get something like x120,I think you could push the mag further but my next move will be to discover where to look in the sky.

[Lindsayanng]

@Glowjet - I completely understand what you are saying. My husband actually had already mentioned the movement of objects in the sky and the issue with very long exposures... Bringing me to realize that any "great" photography probably will not happen with this scope.. That being said, no harm in playing!! We do have a VERY sturdy camera stand (not a tripod) that can be used to place the camera on the scope without any movement or bounce... But yes - we can't exactly follow moving objects.

I am just really excited to simply look through it to see things other than the tops of trees!!

@Yeoboy - I think we could be ok with a smaller field of view; I know the sky pretty well and have been pretty precise at finding things manually with binos and the naked eye.. I want to push as much magnification out of it as possible.. i'd LOVE to see the rings of saturn.

[John]

.... I want to push as much magnification out of it as possible.. i'd LOVE to see the rings of saturn.

200x is the max for this scope but in practice a little less will work better most of the time. I find with my 102 refractor (a Vixen) that 150x - 170x is the most I can usefully use on Jupiter. You will be able to see Saturns rings at even 40x.

Many fine views of other objects are to be had a low / medium magnifications - a scope is not all about POWER ! (it's actually more about light gathering).

[Lindsayanng]

jahmanson - i guess i kinda mispoke - i don't want to get the most power as possible, I want to get the best "view" as possible.. which, from what I seem to be learning, is a mix between magnification, scope, and clarity.

I am STILL waiting for a clear night so that i can look at anything!!!!

[andrew63]

If you are up early - about an hour before dawn, saturn will be low in the east, but over the coming months it will be a fine sight to observer at a more reasonable hour! If you have not seen saturn before it is always a great thrill to behold.

andrew

[Lindsayanng]

Yea.. I'm a runner, and most runners love to get up before dawn to run.. there is NO FREAKIN WAY i will ever get up at those hours.. I will, however, go out running at 11pm and go star gazing at 1am!

[glowjet]

With the question of eye pieces you might like to consider the Orthoscopic range, your scope will cope well with them and should give you very nice clear views of the Moon, planets, single and double stars etc, the field of view is on the narrow side but the ep`s make up for it in visual quality, they come quite reasonably priced s/h on Astro buy sell, there is little to choose between Baader or the Japanese circle T , have fun

John.