What is the cure for Aperture Fever

[albedo0.39]

Tearfund:-

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[Doug]

Need some help...Inspired by some dark skies and perhaps wanting to walk before I can run, I'm thinking of upgrading to a new 'scope

see here

Here's how I rationalise it:-

1. It fits in a smaller car
   
2. It has a great name behind it
   
3. It's sufficiently bigger than the 'scope I have to see a difference
   
4. It's got a very nice optical set up where the figure of the mirror is known and engineered.
   
5. It's dead sexy
   

Here's where all the logic kicks in:-

1. I've only had my current scope since May
   
2. I haven't even got any decent EP's sop how on earth can I say I've had the best out of my current set up ?
   
3. I wouldn't use it enough to warrant the cost
   
4. It's blatantly expensive
   
5. They recommend a Paracorr
   
6. Posessions aren't everything - that sort of money would feed an army in Africa and it's obscene capitalism
   
7. some people have a lot more fun with a lot less than the scope I have now...I'm being stupid
   

What would you do ?

I can understand the way you fill and if the money is not a major problem I would say go for it in a heart beat, when I started to read you blog I thought you had a small scope ,but you don;t do you a16"Dob is a great scope and is not small I think you should be looking at a few good eyepieces nagler and ethos them see what you really have there, i was looking though a 15" Dob two weeks ago with a meade 18mm Ultra wide and the views are fantasic save the 22" for retierment :-)

But if you do go ahead let us all know were you are setting up and Im shore there will be a lots of us coming to see it and I will bring my Naglers as you will not have any money left :-D

Doug

[arad85]

I haven't even got any decent EP's

Having just upgraded to a 13 Ethos and a 31 Nagler, I have to say that with a 'scope like you have, I'd be looking at better eyepieces first. I haven't even had a proper session with mine yet (rain, wet, moon up, clouds have conspired to give me 2 half hour observing sessions so far), but I have managed a sneaky look at the moon and a few objects to know that good quality eyepieces in a reasonable 'scope is amazing! So far, I've had:

• The moon at 115x in the Ethos and it filled about 90% of the eyepiece - so much so that it is a bit disorienting at first (not to mention ruins any dark adaptation you had). I've seen more magnified views of the moon, but not as impressive. It's almost like looking at some of the really good moon mosaics posted here.
  
• Stumbled across M15 as I was panning around the sky with the Ethos (100 degree and decent mag really does help in a dob!)
  
• Had some lovely views of some double stars - far nicer than I'm used to - not sure why, perhaps it's just the widefield conspires to make it seem that much nicer.
  
• Found that, the Ethos seems to barlow well (I've not been a fan of barlowing before I bought this eyepiece) so now I have a 6.5mm 100 degree eyepiece as well!
  

To be honest, if I had money burning a hole in my pocket and I was in your position, I'd opt for either the 6/10/17 Ethos or 8/13/21 Ethos and perhaps a 31 Nagler. If you were after saving some money, the Skywatcher Nirvanas (7/16/28) and perhaps a Parcorr (which you may get benefit from anyway). Add to that a new focuser (Moonlite perhaps) and I think you'd probably be done for all but the darkest of skies.

[dark knight]

Surely the cure for aperture fever is to buy a bigger telescope.........

[johninderby]

Surely the cure for aperture fever is to buy a bigger telescope.........

First you win the lottery then you buy a BIG scope.

......John

[Macavity]

Hello Macavty. I built a couple of Mak binoscopes but found the rather small FOV and the image shift issue when focusing somewhat defeated the object. I ended up making a 12" f3.5 reflecting Dob binoscope which probably reaches the point of diminishing returns based on cost. Anything much larger might be just as well be a single unit with a binoviewer.

Thanks Peter - Interesting. Not to start a parallel thread, but ideas of binocular viewing have interested me. Of course, it all depends on this idea of "less eyeball noise"(?) versus (inevitable?) Binoviewer light loss? I sense, for mere mortals Bino Dobsonians are fantasy, but some folk do see this as the way to go... for extra "aperture".

Really Cool Dobsonian Telescopes

http://www.telescopebinoculars.info/

etc. etc.

But ALL far beyond my resources - Both financial and physical!

[albedo0.39]

I think the issue of EP's is not a wasted subject. I have had some extensive time looking through the Naglers and Ethos lenses along with Tak's, Pentax's and so on. All were great (incidentally the 100 degree Ethos wasn't entirely to my liking but hey ho). I then tried the Skywatcher Nirvana (AKA WO UWAN's) and was so very very impressed.

Good eyepieces make a massive difference no doubt and that seems to be a strong steer for me. However, I'm beginning to think of David Lukehurst as a viable option or a great 2nd hand scope.

No decision yet (right now, I need a mountain to get over the clouds or perhaps take up radio astronomy - this weather is rubbish)

Thanks for all feedback

[tooth_dr]

I just found these photos on my laptop. Our local astro club went to visit this guy with a huge dob, cannot remember if it is 32, 34 or 36" but it's big nonetheless! Surely this is the ultimate fix for the amateur with apeture fever

[great_bear]

I have recently had a rather dramatic demo of what happens to EPs under the stress of a fast focal scope - F5 is fine

F5 is already past the design focal ratio of most basic eyepiece types, causing poor performance at edge-of-field. I wouldn't buy an F5 scope again having seen the difference at F15.

(unless I was getting a big dob and had no choice)

[great_bear]

Alternatively, instead of spending all that money on a new scope - you could put the money towards having more weekend breaks at dark sky sites...

[John]

Alternatively, instead of spending all that money on a new scope - you could put the money towards having more weekend breaks at dark sky sites...

Thats a great answer

I have a 12" scope which I use from my back garden and I enjoy the view it provides but I am afflicted by a certain amount of light pollution and heat rising from surrounding houses.

When I used a scope with the same specification from a dark sky site (SGL4 as it happens) I was rather knocked out by the views - it was like adding 30% or more to the aperture

John