Hayneedle.com still have Televue EP's at Neaf 20% sale price

Fast forward 20years and Televue will release a 360 degree FOV eyepiece - you'll be able to see the back of your own head....

johnomahony wrote:

Calibos wrote: UhOh! Looks like there is going to be a glut of Hyperions in the For Sale section then. :laugh: !!

Don't worry about the competition. I'll be selling mine in the Ozzy market place where I am gauranteed a better price
Astronomy is about compulsive buying. We spend big sums of money on items, use them twice a year and then blame the weather. I think we're all a bit nuts

Nuts is one word you could call me, Impulsive is another or simply downright bat**** crazy !!

I done a vewy bad ting :blush:

I borrowd a grand from the oul fella which I'll pay back when I sell the platform, Hyperion Set and a few other astro odds and ends and I've eh.....I've eh.....

I've ordered the 3.7sx, 8mm, 10mm, 17mm and 31mm Nagler :bigshock:

I just cannot let €4500 worth of EP's from Teleskop Service for €2300 from Hayneedle pass me by. I'd be kicking myself next year paying Double the price for each EP to complete the set when for the sake of some short term borrowing of a grand from the oul fella would have saved me 50% on the whole lot.

Even if I get hit for Customs and Vat and even when you take into account the interest I'll pay on my Visa card on the amount I have added to my balance till I clear that amount off. I'll still have saved a fortune by jumping now.

The whole thing is not impulsive in terms of me suddenly deciding I wanted the full Ethos set out of the blue. I've always planned to sell my Hyperions and get the set of Ethos its just I intended to do it over time starting next Winter. Its impulsive in terms of seeing the offer and doing some math over the last few days and with a bit of financial jiggery pokery deciding that I'll accept cutting things close to the bone disposable income wise to make it happen all in one go now to take advantage of an amazing confluence of Manufacturer discount, retailer discount and exchange rate. Same thing happened and I did the same thing for the Lightbridge. Got my brand new 16" Lightbridge from TelescopeHouse for €1100 instead of the price every else at the time of €2400.....and that all worked out in the end.

Fingers crossed it all works out or else you'll see me on a street corner selling me body :laugh: :laugh: Or if no one wants my 'Body', maybe I can sell some body 'Parts'. How much for a Kidney these days! :laugh: :laugh:

yip, you're nuts : cheer:
you're in good company though. : cheer: giving me ideas.

A 3.7mm ep, what magnification will that one give you ?
Lets hope you get a chance to use them alot.

Dave_Lillis wrote: yip, you're nuts : cheer:
you're in good company though. : cheer: giving me ideas.

A 3.7mm ep, what magnification will that one give you ?
Lets hope you get a chance to use them alot.

1800 focal length by 1.15x paracorr magnification factor = 2070mm

So with Paracorr in place

31mm = 67x
21mm = 98x
17mm = 121x
13mm = 159x
10mm = 207x
8mm = 258x without paracorr 225x
6mm = 345x without paracorr 300x
3.7mm = 559x without paracorr 486x

I remember being told I would barely use my 5mm in my old 1500FL Orion never mind my 3.5 Hyperions. Got to use my 5mm over 50% of the time and got to use the 3.5mm every 5th or 6th session at 428x. I think there are several reasons for this. Numero Uno on the list would be that the seeing is not as bad here as most people assume as long as the Jetstream is not overhead. I think being beside the sea helps but the main reason is that hardly anyone addresses thermal issues with their scopes/mirrors. Deal with the boundary layer and one will often realise that the bad seeing that others are...ahem...seeing, is in fact thermal issues in their scopes. ANother reason might be that I perhaps prefer to tolerate empty magnification in terms of detail just for the image scale. Seeing might mean I see no more detail than the next guy using a much lower mag but I stay at the high mag to see whatever detail is available at a larger image scale.

Point is, I don't think a 3.7sx will gather that much dust in my EP case.

[EDIT] Thought the game was up just there. 2 emails, one outright cancelling an order and the other wanting phone verification for security purposes. Turns out it was just the billing address causing problems. Sorted it with both them and Visa and while I was at it chanced my arm and asked for my credit limit to be increased. Visa said no problem, so now I don't have to borrow the money from the old man. What looked like the house of cards falling down actually turned out to be the thing that resolved everything.

Only problem now, is I don't have the money to get some bits I need to finish the scope. That will have to wait till I start selling some stuff instead. Maybe I'll have her ready for Autumn observing season :whistle: :laugh:

well, I can tell you Keith, I made a very interesting find about "seeing" when I got the obsessionator,
I have a black shroud for it (been a truss dob) and I can tell you that much more often then not that the views of the planets significantly deteriorate when I use it. I was surprised at how noticable it was and now never use the shroud when planetary viewing/imaging. This was something I had heard of but didnt think it would be so significant.

There was an article a number of years back in sky&telescope about thermal boundry layers hovering above primary mirrors, I must dig it out and have a re-read.

Have to agree that the Ethos are indeed overpriced as amazing as they apparently are. When the plan was to slowly accumulate them I was able to rationalise the expense by telling myself that these would be my lifetime EP set. Now of course just like prison sentences, life probably doesn't really mean life :laugh: cause there is bound to be something better available in the future but that said the Naglers stayed at the top of the wide angle multilensed EP heap for what? 15 years with a few revisions along the way? If I amortise the cost of each EP over a decade or more then that €700 EP doesn't sound so bad at €70 a year.

So I could rationalise the full price expense. However, with the savings I have made, I reckon they are a great investment too TV EP's hold their value well when it comes to sell anyway. The fact that I will have got them for 50% of the price anywhere over this side of the pond means that I reckon I'll be able to sell them for a profit for a fair few years into the future should I ever decide to.

In relation to Boundary layer issues. Seems to me that with a reasonably low mirrorbox and open cell at the back, there is enough of a draught especially if you have a cooling fan to blow off that boundary layer and for it to quickly get out of the lightpath whereas with your shroud on you weren't getting help from the breeze to clear the boundary layer. ONly problem with not using the shroud is body thermals blowing into the lightpath if you are upwind of the scope. Did you ever defocus on a star till you see the secondary silhouette and then hold your hand infront of the scope. The thermals coming off your hand are mental!! Doing the same with a defocussed star one can also see atmospheric seeing and boundary layer effects. Atmospheric seeing looks like a fast flow across the face of the mirror in one direction. Boundary layer air on the mirror looks like swirling and mixing whirls and vortices.

How I'll have resolved all these issues on my LB16 is to use a shroud as lightshielding and to prevent body thermals getting into the lightpath, lined the metal OTA and UTA with a composite sandwich of felt, corrugated cardboard and cork (Poster board to you and me ) topped off with Flocking paper to eliminate tube currects caused by a super cooled OTA. Because my mirror tub is a lot taller than a premium dob I can't rely on help from a breeze to clear the boundary layer so am implementing a fan and ducting system. Baffled 120mm cooling fan at the rear blows air at the back of the mirror to cool it and all this air is directed around the mirror and up into the OTA where it is directed in a laminar flow across the surface of the mirror by vane/duct system made from carved polystyrene. On the opposite side of the mirror I'll have 3x 60mm low prfile fans mounted to the inside of the OTA which suck that air and blow it out through the side of the OTA. In otherwords I'll be taking the jogsaw with metal cutting blade to my metal OTA tube Last but not least, I'll be repurposing the PWM temp sensor controlled heater output on my Dewbuster dew controller to power the fans and indeed repurposing the actual temp sensor itself from secondary mirror duties to cooling duties. Normally the sensor measures ambient and mirror temperature and when the mirror cools below ambient it triggers the secondary dew heater to come on to heat up the mirror. By reversing the wiring and mounting the sensor to my primary instead I can have it power the fans while the primary is above ambient and when it detects the primary is approacging ambient it slows the fans down and if it can catchup with the temperature delta and achieves ambient then it'll shut the fans off completely because as you know once the mirror is at ambient then there is no need for boundary layer fans anymore because at ambient the mirror is no longer generating a boundary layer anyway. Thus the fans can be powered down saving battery juice. My problem in the past was that while observing, the fan noise became like the ticking of a clock. ie. I know longer heard it. I'd forget the fan was on and leave it on all night and end up with a flat battery This automation of the fans will solve that little problem.