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deeneil
05-09-2009, 12:35 PM
Hi everyone.
After a lot of delibation I finally purchased a Saxon 1309EQ2
I got a 4mm ,10mm and a wide eyerelief peice 25mm. after a long wait in melbournes unpredictable weather i could finally get the telescope out and use it. Although i was adviced that I could see the saturn rings and I fell for it:doh:. I believe it was just see "saturn rings" w/o resolution:D and if i am right saturn is not visible at this time of the year.
Anyway now the time has come to make a decision about EP or Barlow Lens. Browsing thru the forums I learnt that EP is a bettr option compared to barlow as the latter looses brightness and definition.

1.With all these tech spec and me not being:einstein: I am lost as to which one to go for.
Please adivce as to how can I make the most of the telescope that I have other than disposing it.
I have gone thru Wiki and I believe Plossl one is the one to go for. What do you guys suggest as the best economical option for a beginner who doesnt want to constantly buy accessories. What sort of quality spec shud I be looking at?

2. As I am close to the CBD approx (20 mins away) what sort of quality filter/s shud I be looking at for better viewing experiene and what is the best best option for planets and also solar filter.

3 I have a Fujifilm finepix S5700 auto digital cam. How can I get the best out of it for astrophotography. What other attachments am I looking at?

Can you guys please give me the best possible options/combination for the lot? Where can I find these attachments/ accessories at the lowest prices?:help:

Cheers
DeeNeil

Guys please feel free to give me the additional tips and tricks to enhance my experience, I read in one of the forums that once can use an additional tube to increase the F/L.. I would also like to have the tech terminology to get a better idea and mingle amongs other users.what is that additional tube called?

Paddy
07-09-2009, 07:17 PM
Hi Deeneil,

Welcome to Ice in Space! My feedback is that if you are fairly new to your telescope, it might be best to wait before investing in new eyepieces etc. Forgive me if I've got this wrong, but you sound like you are still finding your way around and often you will discover more observing power as you get more experienced. Going to some star nights is of great benefit. You can learn a lot about the sky and which equipment might be useful. I could highly recommend the Snake Valley camp in October as a great place to get help with gear and observing - alas I won't be able to make it this time.

Having said that, your highest mag eyepiece will give you about 160x which is good for planetary viewing. Usually the maximum that you can use is about 300x due to atmospheric disturbance and I find it quite uncommon to be able to use this much magnification. About 160x is often the upper limit of magnification for my observing due to the limitations of "seeing". If you want to get to 300x you would probably find a barlow useful as plossl eyepieces of short enough focal length to achieve this in your scope (ie 2-3mm) have very little eye relief. Barlows can actually improve the optical performance of eyepieces in some settings, so they are not a second best option by any means.



Hope this helps.

deeneil
08-09-2009, 08:40 AM
Hey Patrick
Thanx for the reply! I dont think I wll be able to make it to the camp myself. Anyway there where some more questions that need some attention. I was wondering if you could also help me with that.
Even with the barlow compared to Plossl what sort of mag shud I be looking at? I believe there are 3 types. which one do you recommend?
Cheers
Deeneil

astro744
08-09-2009, 09:03 AM
I find a low power sweep of the sky to be very rewarding and may I recommend a Tele Vue 32mm Plossl, currently available at a very good sale price in Aus, to give you 28x mag. and 1.7deg true field in your telescope and an exit pupil of about 4.5mm. (I'm working on 900mm focal length & 130mm diameter mirror).

This will be your premium low power sweeping eyepiece that you will use most often. You can then add a premium 2x Barlow to complement the eyepiece at a later stage to give you in effect a 16mm eyepiece. If you wear glasses and need the eye relief go with the Tele Vue 2x Barlow and perhaps later a 3x Barlow. If not go with a 20mm or 15mm (or both) Tele Vue Plossls to complement the 32mm Plossl. This will form a premium Plossl set that you will enjoy using very much. The are also 25, 11 & 8mm Plossls that complete the set should you want other powers without the Barlow.

Since you are close to the CBD, a UHC filter will help and there are plenty on the market to choose from each with different characteristics. In fact there are now some very low cost UHC & O-III filters that may be worth trying. The narrowband UHC & O-III are for boosting the contrast on an object once you have located it. They are not meant for use whilst sweeping since they can block out too many stars. For sweeping a more gentle filter is desireable but then you wont get as much a contrast boost as with the narrow filters but for your location a more gentle filter can be left on the eyepiece just to darken the backround a little but you may find galaxies disappear or become fainter with a filter in place.

There is another way to darken the backround and that is to use an eyepiece wihich will give you less exit pupil and may I suggest the Tele Vue 24mm Panoptic. It is costly but will give you a beautiful 1.7deg (68deg apparent field) at 37x and 3.5mm exit pupil.

As far as Saturns rings go; well the planet is setting soon after sunset at the moment, but its rings are edge on. The rings will slowly open up over the next 7.5 years after which they will start closing again.

Paddy
08-09-2009, 03:57 PM
Hi Deeneil,

If you bought a 2x barlow and used it with your 4mm ep, you'd have a mag of 300x, which you may be able to use on nights of very good seeing. Other nights you would have a wobbly image, like a mirage. A 3x Barlow with your 10 mm ep would give you about 200x - you'd use it more often, but it would not be very different to using your 4mm by itself.

The best way to improve your observing results is practice. you will see more and more as you look. Having someone help you will make a huge difference. It might be worth putting a post in the beginners forum to see if there is someone near you that you can do some observing with.

Jupiter would definitely be worth a look as a starting point - it is the brightest thing in the night sky at the moment and you should be able to see its moons and some cloud bands etc.

Regarding equipment and observing, you may find the following link helpful.

http://www.skyandtelescope.com/equipment/basics

Don't give up, take time and you will see more and more, but some of it will seem very subtle at first, not like what you see in astroimages.

All the best!

deeneil
10-09-2009, 10:28 AM
Thank you very much astro! that information was appreciated. Liked the fact that you could explain in greater detail about the set formed with the diff plossl without the use of barlow.

The othe concern that i have at the moment is the attachment for my Fukifilm S5700 which is an auto focus but also has provisions for attaching lenses to it! What sort of equipment am I looking at to begin with astrophotography?

Thank you Patrik for the additional links that u have provided. Help much appreciated. I have already seen the Jupiter with its moons. I could see the bands on it too. The only concern is eventhough it was clear it did not magnify the image to my expectations and having a 900mm F/L with 130mm mirror (being one down from the next and probly the best Saxon)
with that sort of image on the 4mm lens that came with the equip. how would I go ahead with the astrophotography? sply on a autofocus lens!!:shrug:

Cheers
deeneil

deeneil
10-09-2009, 10:59 AM
:help:

Astro744 can you plese clarify what you mean by set!
Is it that you can thread the EPs into one? or is it that interchange on to the tele to get the effect
If latter is the case. than which one would be a better option, like you said I have 900mm FL and 130 mm app
which is like F/6 if I am right and the max on EP shud be 42mm if I am correct. I dont wear glasses and have a reasonable eyesight:eyepop::D
SO if the "set" can be made by threading the EPs together what does the final EP mm boil down/ up to? :shrug:
and if thats not the case whats the best option for me to get the max Magnification with resonable brightness? is it a Plossl or anyother EP or the ones that I have + a barlow? or is it a set of Plossl ---"---""----""?
:D MAN!! I know I am driving you guys nuts with these doubts!! but some day I assure u when I become a pro at this I will take the questions for ya all :P

Cheers
Deeneil

Was looking thru google and other sites for the EPs you mentioned and found that there are 2 types ED and LE what are they and which one shud I be lookin at?

erick
10-09-2009, 11:28 AM
By "set" he means a number of eyepieces of different focal lengths - normally the same "make" and "model" - eg. Televue plossl eyepieces.

Eyepieces are used one at a time - they don't screw into each other. There are those who prefer to have the eyepiece at the correct focal length they want, rather than using a different focal length with a barlow lens.

You've correctly understood that, with higher magnification comes lower brightness of the image reaching your eye. But remember, high magnifications are often defeated by the "seeing" conditions - the image is yuck!

deeneil, you need to sit down with someone and look at and discuss eyepieces, then spend time at your telescope with some borrowed eyepieces. Best place for this is a starcamp. Why don't you try to get to one of the camps coming up? Alternatively, put out a request and I'm sure someone would be happy for you to visit with your scope, or maybe visit you.

Also go back over eyepiece discussion threads on this site - you will find a lot of information there.

Cheers
Eric

astro744
10-09-2009, 01:28 PM
Exactly thanks Erick.

I mentioned the 32mm Plossl since it is currently available at a very good price in Aus. Go slow and get your eyepieces one at a time and like others have said try and look through other peoples telescopes and eyepiece combinations to see what you like best. If that's not possible just enjoy what you have until you get a feel for what you can and cannot see.

Have a look at http://www.televue.com/engine/page.asp?ID=131 and http://www.televue.com/engine/page.asp?ID=277 for more info on eyepiece selection.

deeneil
10-09-2009, 02:13 PM
Hey
Thanx for the trouble taken! after readin what eric hd to say I was browing thru hundreds of pages and also came accross the links that you had given. I also found out that ED2 EPs are better than most out there and the ED2 3.5 I believe is good for the magnification vs clarity as compared to the super 4mm + a barlow. Also the manufacturer who I could get onto told me that for astrophotography ED2 21mm is better option.

Astro, how does it work? is it like the rest on the magnification is taken care of by the CAM? or is it the FL of the EP?
Cheers
Deeneil

astro744
10-09-2009, 04:09 PM
I'm not at all familiar with afocal photography which what I believe you would need with your camera. Have a look at http://www.televue.com/engine/page.asp?ID=237 and perhaps also others may chime in with some help.

I would say that the things that would affect image scale would be telescope focal length, eyepiece focal length & camera lens focal length. Tele Vue call it digiscoping and have a list of eyepices on the following table (last column) http://www.televue.com/engine/page.asp?ID=144 They also sell eyepiece to camera lens adaptors. (Talk to BINTEL being Tele Vue distributor in Aus).

It looks like long eye relief eyepieces work best and there are suppliers (also try BINTEL) that sell eyepieces that are specifically designed for afocal photography (digiscoping) and are called projection lenses.