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Hitmangwp
23-09-2015, 07:26 AM
Hi guys.
Just bought myself a CPC 800 GPS XLT Computerised Telescope.
I understand it comes with a basic eye pieces.
So my question is what extra eye pieces should I be looking at to get the best from this Telescope.
This is my first Telescope and I want to get the most out of it.
Thanks.

GaryA
23-09-2015, 09:55 AM
I have never had any concrete information from any of the Forums. I have exactly the same type of Telescope as you and frankly trying to get information which is correct is like a Dentist extracting a tooth!
Always wonder if I am talking to shop owners who want us people to end up with a pile of crap lenses until we end up with what actually works. Just saying!
I am using the Plossl fully multi coated Lenses which are to me ok to look at the moon but chasing quality detail on the planets forget it!
Try getting crisp details in Deeper space for Nubulas etc forget that also. I have a lot of gear but useless without the right lenses as you and I have already experienced.
I have even gone to a Forum which had a Celestron Site but the info from there was useless as it was conflicting too much with peoples ideas.
If there are conflicting ideas from people who are looking for the same thing ie deep space or planet viewing then you would think there ideas are the same! The reason I say this is Celstron make a pretty good scope which must have quality control in place , so therefore there should be very little difference between your scope and mine regardless where you live on this planet if in the same temperate zone north or south of the Equator. Do I need correcting?
I have read my Celestron manual through from cover to cover and I have bought the Camera Extenders but still crap.
Celestron are so behind in their manual for the CPC 800 they are talking about only cameras that use film not digital.
Well that's in my manual anyway. I don't think it matters though.
So you can image you may have to join a local Astronomy Club and hopefully someone is operating the same Scope as yours and you can see what he is using and just copy.
With this hobby when you start off and have not joined an Astronomy Club I think us people are leaving ourselves open to Sharks quite frankly!
Best of luck with your endeavours!

Tinderboxsky
23-09-2015, 11:18 AM
Hello Grahame,

In my opinion, you will get a lot more out of any potential future eyepiece upgrades if you first spend the time to gain observing experience with what you have.
Given this is your first scope, I would highly recommend you put off any eyepiece upgrades until you have at least 6-12 months observing experience with the eyepieces that came with the scope. You need time at the eyepiece to train your eyes to tease out faint detail, to understand what is possible with low-medium-high magnifications, how the image dims as magnification increases, the differing fields of view, the effect of the moon and other light sources on dim objects, judging what DSO's are going to be visible through your scope etc.
But perhaps most importantly you need to gain experience observing in different seeing conditions (atmospheric conditions) so that you can properly distinguish between the effects of poor and good seeing conditions when assessing your observing outcomes.
Without all of this experience, trying to make sense of the many varying suggestions for eyepiece upgrades will be difficult as Gary has found. The many suggestions you see on this forum will be well meaning but made from the perspective of their personal preferences and experience. There is no one fits all answer to this. Spending more money without some experience under your belt is unlikely to deliver the results you are looking for in the short term.
So, my advice in these situations is to take two aspirins, lie down and wait for the urge to pass.
Can you find a nearby observing group, other interested observers nearby where you can try other eyepieces to help you build your experience?

Cheers

Steve

raymo
23-09-2015, 12:47 PM
Gary A, I don't know where to start with your comments. Firstly, eyepieces are like scopes, no one type will do everything really well.
A decent Plossl will produce good planetary images, just a gnat's
whisker less sharp than eyepieces designed for the purpose, such as orthoscopics.
Secondly, fine detail on planets is mostly very elusive, and is only
visible on occasions when the planet is high in the sky and the seeing
is unusually good. Thirdly, your scope is a good all round one, but refractors and Maks are better for planetary work. Even Newts are marginally better, having smaller central obstructions.
Lastly, nebulae are by definition nebulous, and therefore don't usually
present sharp images, with the exception of planetary ones.
I suspect that you are expecting too much from your scope.
Everything Steve just posted is spot on.
raymo

brian nordstrom
23-09-2015, 03:31 PM
:thumbsup: Raymo is bang on here on Plossl,s and SCT,s these 2 work very well together as given the long 2000mm focal length you don't need to drop into the. <8mm range for high power planetary viewing, a 15mm is fine.
Also plossl,s give great views when the atmosphere steady,s like any other , perhaps except the good old Orthoscopic .
I know this as I use TV Radian,s for my higher powers but find plossl,s to be as good in my C9.25 .

I would stick with the eyepiece the scope came with and perhaps invest in a GSO 2x Barlow for high power

Brian.

barx1963
23-09-2015, 06:32 PM
Grahame
Steve's advice is exactly the advice I would give. Try using the eyepieces you have for a while. It is very easy to spend some serious cash chasing a "perfect" eyepiece and end up not happy with any of them.
So once you have had a couple of sessions, write down your impressions of the eyepieces and then come back with your thoughts and see what people say.

One of the frustrations with eyepieces is that not all eyepieces work perfectly in all scopes. But manufacturers will rarely tell you that, after all why would they want to knock out a whole market segment?

So often times you need to try other people EPs in your scope and that is where observing sessions, camps and clubs come in handy.

Cheers
Malcolm

The Mekon
23-09-2015, 07:40 PM
GaryA, I am sorry you feel like you have had no help from this forum. I am unsure of what your expectations are, but with your scope and the eyepieces supplied, you should at least be able to see Saturn's rings, the Cassini division, the ring shadow and on good nights bands on the planets surface. If you have not seen this, perhaps the collimation is out. Do not expect to see the Enke division or radial spokes on the rings with your scope! As others have said in this thread, use the eyepieces you have until you decide what objects interest you most. I have 6 televue eyepieces which I have collected over a 25 year period - you don't need to do everything at once. My latest Televue is a 17.3 Delos and I like this eyepiece more than any of the others!

Hitmangwp
24-09-2015, 08:14 AM
Thanks guys for the sound advice.
Will spend some time with my new toy next week when I get home.
Can anyone tell me if there is a club around the Mackay area here in Queensland ?

SkyWatch
24-09-2015, 05:13 PM
Hi Grahame,

There is some good advice there about waiting, but for what it is worth I got a Televue 32mm Plossl (62x) for my CPC800- which gives the maximum possible true field for a 1 1/4" eyepiece- great for putting the whole moon (and a bit more) into the FOV, and really nice for larger nebulae.
If you want a larger true field, you will need to get 2" eyepieces.
I often use a 13mm T6 Nagler (154x)- but that is a lot to pay for a first eyepiece unless you really know what you want.
For high power I have built up a range of eyepieces over the years, but a very good value range is the Long Perng ones ($79 at Andrews at present): I often use the 9mm which gives a nice sharp view at 222x. They all have 20mm eye-relief which is great if you wear glasses. They also have 6mm, 12.5, 14.5 and 18 in their range.

- and I often use a 7.5-22.5mm Williams zoom when I am using the scope for public nights. The only problem with the zoom is that it only gives a 27' true field at low power (as opposed to the 45' true field for the 32mm plossl). All zooms give smaller apparent fields at lower power than higher power, and a lot of people don't like them because they feel they don't have the same quality as dedicated fixed FL eyepieces. If you go down the zoom track I think it is important to spend a bit more and get a quality one. (Unfortunately Williams don't make the 7.5-22.5 any more).

GaryA: sorry to hear of your hassles- but I haven't had the same problems as you with asking for advice. Generally people have been very helpful, and rarely in my experience do they have an axe to grind. You might try the above as well...

- and for both of you: I found the diagonal that is provided with the CPC800 wasn't very good quality. I replaced it with a 2" GSO quartz one: and all of a sudden I got stars with proper Airy discs instead of little fuzzy blobs... An essential upgrade in my opinion. GaryA: you will also need to give the scope time to reach ambient temperature to get the best views. I have had some wonderful views with mine (especially after I got the new diagonal): and I have even seen something where the Enke division should be on Saturn. ;)

Good high power views are dependent on reasonable eyepieces (almost any eyepiece will give sharp views right in the centre of the field), proper cool-down, proper collimation (usually not a problem with the CPC800), a good diagonal, and good atmospheric conditions- so don't expect a sharp view over 200x every night!

All the best, and happy viewing,

Dean

GaryA
24-09-2015, 08:45 PM
Actually with my apology, I would further like to add is even hard for me to attend a meeting during the week on a monthly bases as we have only one club in my area but they meet over an hour away from my house and the meetings start at 8pm and finish late. Mostly they are during the working week. I have to get up early in the morning..
You see although helpful your information there is not a common way to go where we are all seeing the best of what we got as it is an item you have purchased which is giving you a better view of the night sky but is it the best view? I hope I have sorted that out.
Giving reference to most being like astronomy shop keepers you then will understand what I am talking about. If Not its like this, " Its whats in my shop and its the best..."
To nail it in what I have said I look at all your answer written here and I am thinking " Gee looks like I have to buy all these things people have mentioned here to get the best out of my scope...
I also had to get a reaction from this group also as I want have a look at what you all are saying and visit the Astro Scientific Centre in Singapore as I am going over there to stay in Singapore for a few weeks with friends.
So collectively I have added all your information here and I am going over to visit them and hit them with questions. This does not mean I will get suckered into buying from these guys either.
Not only do I have questions about lens etc but how to take good pics and what I really need to do it because this would be the first visual meeting with people with the same interest. You see i am a real fanatic Photographer. I have lens that do the job and also lens the really do the job. I have tried out many lens just for terrestrial work and do have a very good idea about whats good and bad. Astro photography is a step side ways to what I have done as it takes a lot of time to do wildlife and terrestrial photography where astrophotography is pick your night and hopefully stack a view good shots together and make that progress as I am halve the way there where my Scope sits on its pedestal and don't have to worry about carting it around and spend considerable time setting up as its all about time. I can see the rings of Saturn (One time I made a mistake calling Saturn, Satan and then made the mistake twice without realizing and somehow this created a senior member to laugh at me in the written sense in this Forum. Ah well **** happens) and sometimes see the smudge outlines in Saturn and Jupiter as well but I want to see what a lot of other people are seeing with my setup and also with exactly the same camera I have - a Canon 400D. I know those things about exposures and such and where you get the tracking off happening but that's not the problem. The problem I want to solve is " I want to see something extremely good that I can use my Camera to take a good shot of. I don't won't to spend 6 to 12 months looking at smudgy looking images that are the size of a pea. I am over the initial excitement of look at the planets and need to progress. I am not impatient neither although some of you people :( seem to think differently. I hope I have smooth that over a bit for you all to understand what I have written earlier. :thanx:

GaryA
24-09-2015, 10:15 PM
Thanks Dean and those other people, you have introduced me to things I need to understand clearly in regards what am I going to do in regards getting the right gear so I can talk on the same level as you. To get a good size image I may need to have to go your way - with 2" eye pieces and Diagonal as well. So although it does cost a lot of money big deal, can't take it to the grave with you , I must have these instruments ( tools) to get what I am looking for. So can you see what I am aiming at? I can see honing my skills up using the rubbish i have got at the moment, reluctantly, but at the same time gathering the proper lens's and such in that is going to help me to get a good Pic from my CCD camera I have coming (and when it gets Here !!)
I want to always be looking forward to improve like we all are doing here. The knowledge you have is infinite times much more than what a person first joining up has. I was recently talking to a dealer who did quote Williams lens's but who says he is right also as he did asked me what was I using 2" or 1 1/4" lens's. However if he did say for larger images 2" is better, then I would be thinking the same as you but he did not.
This is the part I have to obtain understanding about why he did not immediately hone in and mention that straight up. :confused2:

raymo
24-09-2015, 10:31 PM
Gary, A 2" eyepiece of any given focal length, simply gives a wider field of view than a 1.25" eyepiece of the same focal length. It does not give
a larger image. The image size is governed by the focal length of an eyepiece, therefore a 10mm 1.25" EP gives the same size image as a 2" 10mm EP, but a narrower field of view. Many older scopes cannot take 2" EPs, and their owners happily use 1.25" EPs.
raymo

GaryA
24-09-2015, 10:50 PM
You reply is very true but I hope my reply to you all sort of fits into what your thoughts are referring too in a deeper sense. Thanks though. However one cannot make head way if he is not on the same page as you more experienced people are. When I joined this forum and others and having heard and read about where most of these new findings in our universe have been founded, is by Amateur Astrologist so at least I feel if you want information you do come to a forum like this and exchange ideas and not rely on a shop keeper to sell you something that is not quite there.
For instances with my Terrestrial Photography when you want to find something that does the job extremely well then talk on a forum or a specialist with regards to the camera you are using and you will get what you are looking for. You know I at the moment have a DBK Camera coming but don't have a clue also if I have the appropriate gear to run it, but the person i am buying it off has said I needed this and that and that is what i have done and bought the necessities to do the job. However I had hunted over the Forums and had come across this CCD and also saw the pics it took and where quite good after stacking so I have acquired that.
The frustration started really when i went to the Celestron Manual and saw where it says to take photos of the PLANETS use a Tele Extender with an eyepiece. I did not pay sucker prices for this extender but with the lens's I have and my Camera it don't work so what is the point going to Celestron when they cannot even set up an up to date manual for a Celestron telescope CPC 800. This is what I feel.
Have also heard there gear is also not the best at the top range but that's a few saying that and can be taking "with a pinch of salt" but that makes me wary even so. You know I wonder why they have made crap lens's for their Telescope? However thinking about it its the same for good lens's for Cameras also.
:confused2:

GaryA
24-09-2015, 10:59 PM
Thanks Raymo
Just learning all the time. :rolleyes::screwy:

raymo
24-09-2015, 11:25 PM
Regarding crap EPs. Because EPs are a very personal choice, scope manufacturers generally only provide one or two budget level ones,
knowing that buyers will build up their own collection of favoured ones.
High end scopes frequently come without EPs for this reason.
They are also fighting for market share, and try to keep the price
of their products as low as possible, hence some of the low quality
lenses that come with some DSLR kits.
Celestron introduced the Schmitt Cassegrain scope to amateurs 40yrs
ago, and have produced good ones ever since. Many observatories are
equipped with 11 and/ or 14" Celestrons, and even a few 20" ones. Their bottom end scopes are no better or worse than many other budget level products.
raymo

GaryA
25-09-2015, 03:07 PM
So Id say the EPS I was looking for are not of the quality I wanted or expected. The scope is not the problem. I was too eager and was sucked in. Anyway it's a learning curb for me but at least I am talking to people with the same scopes.cheers for that.

raymo
25-09-2015, 03:41 PM
Decent EPs have become available to the less well heeled in recent years. High end EPs are still very expensive, ranging from several hundred to several thousand dollars.
The Superview EPs are great value for a reasonable price, and even
experienced people with high end gear, have conceded that. I think
Bintel stock them.
raymo

doppler
25-09-2015, 04:52 PM
Hi Grahame, there is a casual astronomy group in Mackay that keeps in touch through the tropicalstargazers web site and a facebook page.
http://tropicalstargazers.webs.com/.

Cheers Rick

Hitmangwp
25-09-2015, 07:13 PM
Thanks Rick
Will look them up.

Hitmangwp
02-10-2015, 11:04 PM
Well I love my new toy.
Two nights of Saturn (but the clouds beat my tonight:shrug:) .
Looked at a few galaxies ,and I'd love to get a closer view of these.
I did get myself a TELE VUE 15mm PLOSSL and a 2x BARLOW .
The scope came with a 40 mm PLOSSL and I can safely say that I'm very impressed with my purchase. I can see myself spending many a night outside now.

Hitmangwp
04-10-2015, 12:42 PM
I've decided to save up for a 13mm ETHOS .
A question about Filters.
Can't find much info to split the OIII from the UHC.
Any thoughts or is it a personal choice ?

SkyWatch
05-10-2015, 11:21 AM
I prefer the UHC because it gives you a more "natural" field. For me it is more aesthetically pleasing, and lends itself to viewing more objects. The OIII is very high contrast for emission nebulae, but tends to block out everything else. They complement each other, but if was choosing just one I would go for the UHC.

The Astronomik website gives a good comparison with transmission graphs: http://www.astronomik.com/en/visual-filters.html

All the best,

Dean

raymo
05-10-2015, 11:50 AM
The OIII and UHC are different creatures, made for different purposes.
For general night to night purposes it is hard to go past the Lumicon
Deep Sky Filter. The Lumicon website has information on the usefulness
of many filter types and colours, for various objects.
raymo

GaryA
02-01-2016, 12:16 PM
Hi Hitman,
I went to Singapore Scientific and the Gentleman there said my Lens where very adequate. I have come home with my tail between my legs ( not really, but in deep thought, yes) but more determined to try harder with what I got in my bag of tricks. As Raymo suggested EPs are a personal choice. So I have since been back learnt a bit about the area I live and quality of light and the best time to search the Skies. I have also found that using my 40mm EP I do at times get some really fine views of nebula's , star clusters etc.
The DBK CCD has arrived but have not attempted to use it as the planets and conditions are not the best for viewing at the present moment.
With the Atmosphere or sky conditions, there is days in daylight hrs you can see that show a deep blue sky and I have found these skies to very ideal to star gaze at night. Has anyone noticed that?
New Years Eve was such a day but about 8 PM the winds picked and were very gusty. There ends my night of viewing! Although the viewing around the Orion Nebula was very clear once the winds dropped down for a few minutes.
Also viewing in my light polluted area is that bad!
It is only on occasions and late at night I get quite good detail through my scope and in virtually directly above position.
I only can wish to be able to take my scope into the non polluted areas in the country on a good night but maybe later on I will try that on one or 2 occasions. I say 1 or two occasion as I have time restraints with work and other commitments.
As I have been told I need to steady down and just observe. That's the fun of it. I really feel the heckles work out on the back of my neck when I view a new something. I also keep a diary. One of the easiest things that has helped me is downloading Stellarium and hitching my scope up to that.
This helps a lot because you can see where you are going and also knowing what you are looking at, without just dialing something up on the GPS and travelling a full circle to get to it. To me that is like a cat chasing its tail. Also you have good capabilities to learn where the stars and constellations are in the sky very much easier.
To keep everyone in the loop I have a Large flat screen TV with HI PIXELLING connected to my Laptop and that is for those who want to see what I am looking at which I can pick up with my Canon 700D. This is housed in my out room in the observatory.
Just before I finish- I thought why bother about Constellations and others but really your knowledge of the skies grows so much quicker and can picture things much quicker when having a look up there to see where the constellations and nebula are. :thumbsup: