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8se Diagonal Question

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#1 Frankie38

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Posted 21 September 2012 - 06:51 PM

I have an Nexstar 8se I bought back in March.This is my first telescope.So I am new to astronomy.I have already spent ALOT of money on 1.25 inch eyepieces.Would it be worth the expense to buy a 1.25 inch Tele vue Everbrite diagonal to replace the stock diagonal? How much better would the views be if any? Thanks for any help!

#2 hopskipson

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Posted 21 September 2012 - 07:24 PM

Welcome :bow: Frankie38, I'm not familiar with the diagonal you mention, but you may be better served with a 2" diagonal. If and when you start to use a binoviewer or larger widefield 2" eyepices you won't need a new piece of equipment. Any decent dielectric diagonal should suffice. I have one from Scopestuff manufactured by GSO. Works great and was only $119 US.

James

#3 Midnight Dan

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Posted 21 September 2012 - 07:25 PM

Hi Frankie & Welcome to the Forum!

I doubt you would notice any difference between the stock diagonal and the Everbrite.

-Dan

#4 Don Trinko

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Posted 22 September 2012 - 06:30 AM

visually there would be little or no difference.
If you want to get a diagonal I would get a 2" one. Some of the 2" eyepieces are handy for wide views.
I got one from Astronomics that fits directly on the scope. It is short enough to clean the base at the zenith with the scope mounted all the way forward. All IMO; Don T.

#5 Maverick199

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Posted 22 September 2012 - 07:34 AM

The 2"-1.25" Diagonal will come in handy when you later on add a Focal reducer. Other advantages are better grip, more sturdy feel, clamp type. If you want a good 1.25" diagonal then the Astrotech is very good.

#6 Bob Griffiths

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Posted 22 September 2012 - 08:18 AM

As noted by both Dan and Don.. the addition of a Televue Everbright diagonal is not going to be easily seen with your own eyes...

The Everbright is an extremely good diagonal its just that the human eye is not good enough to see the difference ...

I agree with going with a 2 inch diagonal..sooner or latter you will want at least 1 or 2 low powered 2 inch eyepieces

Bob G

#7 Frankie38

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Posted 22 September 2012 - 02:08 PM

Thank you everyone,for your replies.You guys saved me some money.What would a focal reducer do for me?Does everybody use one? And how often does it get used?

#8 Skip

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Posted 22 September 2012 - 02:25 PM

Hi Frankie,

WELCOME to Cloudy Nights and our little corner of the CN universe. I'll let others answer your question about the focal reducer - I don't use one.

Post here often with any questions and hang around for lots of good NexStar advice. Best of the CN forums right here! :grin:

#9 Maverick199

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Posted 23 September 2012 - 09:01 AM

Thank you everyone,for your replies.You guys saved me some money.What would a focal reducer do for me?Does everybody use one? And how often does it get used?


Increases the field of view by shortening the focal ratio to 6.3 as compared to F/10. I have one and most do to obtain a slightly wider field of view. I say slightly due to the narrow opening for the visual back which restricts the FoV somewhat. Images though are brighter, more contrasty in my views.

How often? would depend on type of object. If I want to see the Double Cluster through a 14mm, then I need to insert the Focal reducer or I only get to see only one cluster. Hope that helps.

#10 Frankie38

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Posted 23 September 2012 - 05:58 PM

Thank you Maverick. I think I will get a focal reducer and try it out.

#11 pcguru2000

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Posted 23 September 2012 - 08:27 PM

Thank you everyone,for your replies.You guys saved me some money.What would a focal reducer do for me?Does everybody use one? And how often does it get used?


I use one and never take it off my OTA. It's screwed into the visual back and not only does it give me much wider views and slightly brighter views, but it keeps bugs from flying into the tube while setting up. Our telescope is great at looking at clusters. This zooms you out so that you notice the difference between regular space and the cluster. Then I use my zoom lens (look at my sig) to focus in on just the cluster for finer details. The type of focal reducer I use is also in my sig.

#12 Frankie38

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Posted 23 September 2012 - 09:00 PM

Maybe a dumb question,but what is a Sig ? I could not find an answer on line.

#13 mclewis1

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Posted 23 September 2012 - 09:58 PM

Signature line or lines

All the stuff at the bottom of each post (name, equipment lists, etc.)

#14 Peter9

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Posted 24 September 2012 - 06:02 AM

Hi Frankie and welcome to the Nexstar forum.

I have a 0.6 focal reducer screwed more or less permanently into my spare A&E zoom for wider F.O.Vs over its range. I also love the view through the 25mm with focal reducer attached.

Regards. Peter.

#15 Midnight Dan

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Posted 24 September 2012 - 08:55 AM

Hi Frankie:

I have a 0.63x focal reducer but rarely use it. It seems like most of those who do use it leave it on all the time. Putting it on and off is a pain. The threads are fine and it takes many turns to get the visual back (or diagonal) off and the FR on. Much more effort than swapping an eyepiece or even putting on a filter.

The way I look at it, you can use it all the time and you'll need shorter focal length EPs to get to the highest mags, or you can not use it and you'll need longer focal length EPs to get to the widest views. Adding it in puts more glass between you and the photons so I just prefer to leave it out.

For imaging, it is much more useful. The scope has a pretty long focal length so if you want to image larger targets you need to add a focal reducer. Since there's no eyepiece in the system when doing prime focus imaging, you don't have any other way to adjust the images scale except a focal reducer or barlow.

-Dan

#16 Frankie38

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Posted 24 September 2012 - 03:01 PM

:bow:This is truly a great forum!! Where people share their knowledge and their experience with newbies like me.Thank you.

#17 Bob Griffiths

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Posted 25 September 2012 - 10:38 AM

Dan I agree about the royal PIA the installing a Focal Reducer on and off 20 times a night gets old real fast..

I just threw money at that problem and purchased a Denkmeier S1 P/S diagonal..

Now I can view with the Focal reducer (or barlow) in less then a second (not counting refocusing lol) and do not even have to touch the eyepiece

Bob G.

#18 bcuddihee

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Posted 25 September 2012 - 03:15 PM

actually if you are thinking about a reduce I would consider a 2 inch diagonal plus a Denkmeier Power Switch. In this way you get three mags from one ep's. With this set up 3 eyepieces in effect turns into nine which is really more than enough.
bc

#19 Frankie38

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Posted 25 September 2012 - 06:18 PM

That power switch looks pretty neat.But kind of expensive.I have already invested in 1.25 inch eyepieces.ES 8.8,11,14,24,and 19 TV panoptic,TV 32 plossl.About an hour ago I found a Celestron reducer on Amart.If I keep this up I will have my own observatory in the back yard.AKA the dog house.LOL.

#20 Sorny

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Posted 27 September 2012 - 12:47 AM

Considering the price of a focal reducer, barlow, and 2" diagonal, a Denk Power Switch is not expensive; it is a bargain. This also did not take into account that going from the reduced to normal and normal to barlow refocus time is about 5 seconds each way; this convenience adds up to extra viewing time, and more viewing time is just about priceless.

Try putting on your focal reducer and focusing in 5 seconds and let me know how well it works out for you. Now, take off the reducer and throw in the barlow... I've been there and done that. Now for me on my little scope, the reducer stays on at all times due to the hassle. Yes, that means that I barlow on top of reducing from time to time... As it is, I can't point to zenith with the reducer installed in my little scope, so I just wait until things are not at zenith to view them (I had to set slew limits, and to get around it I'd have to install a different rail on it to move the scope more forward due to the smaller mount on a NexStar 5 compared to an 8).If a 2" diagonal made sense on my NexStar 5, I'd have a power switch system on that as well (no point at all on a C5 since the rear baffle opening is tiny in comparison to the 8" or my 11").

For my power switch on my 11", it is about 7 turns of the focuser to go from reducer to normal, and about 5 turns to go from normal to barlow with my binoviwer in the power switch. When I'm using single eyepieces, the number of turns to the focus knob are quite a bit less; maybe 3 turns and 2 turns respectively. I'm not really sure since I do most of my viewing with the bino.

The Denk Power Switch will come with a 2" to 1-1/4" adapter so it can use both types of eyepieces. It is nice to have a 2" eyepiece or two for low power views.

Anyway, what I'm trying to say is that you can get by with 3 main eyepieces with a power switch. It is a most convenient way to view and simplifies things greatly. That said, I've got 4 single eyepieces, and 1 (probably soon to be 2) pairs for binoviewing in my kit. Truth be told, I use the bino 80% of the time, and the other 15% is usually the big low-power 38mm widefield, with the remainder split among one of the others (as listed in my sig).






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