Takahashi FS152 VS. Starmaster 14.5″ Hybrid

[gb_astro]

Originally Posted by Satchmo

I don't understand why the owner doesn't just put a shroud around his truss and get on with life

Mark he does have a shroud but claims the thermals pass right through it.

It looks like the standard rip-stop nylon type shroud.

gb.

[wasyoungonce (Brendan)]

This thread rocks..I have the popcorn & beer waiting to read the next instalment.

[TrevorW]

I know of one manufacturer who installs micro fans in there refractors to reduce the effects of thermals

[jjjnettie (Jeanette)]

Originally Posted by wasyoungonce

This thread rocks..I have the popcorn & beer waiting to read the next instalment.

I'm pulling up my chair next to you.

[desler]

Pass the nuts and a bottle opener!

D

[Hagar (Doug)]

Dougs in the back row throwing Jaffas.

[Paul Haese]

Originally Posted by ausastronomer

Paul you aren't remotely qualified to put yourself in Anthony's class. He has been researching active cooling for years and his recent real world achievements speak for themselves. I consider you still have a bit to learn. It is only recently you spent (some would say wasted) a large amount of money on an absolutely superb telescope only to find out after you bought it that it was totally unsuited for the purpose you intended to use it. I could have told you that before you bought it. SDM 14 I believe. An outstanding visual instrument which was never going to be worth a cold frankfurt as an imaging telescope, which was the purpose you bought it for. I believe when you figured out you had made a mistake you subsequently sold it.

http://www.sdmtelescopes.com.au/SDM014.html

Cheers,
John B

Ah you clearly know more about all this than we do.

Anthony and I go back 5 years and that was when he first showed me active cooling. In point of fact he and I were discussing this very matter today when we met at Kapunda for a couple of hours. You have no idea what Anthony and I have discussed privately over the years and what design aspects we have thought about.

I have a peltier cooled C14 and had peltier cooling on the SDM too. I am well aware of the virtues of peltiers systems and have taken more data down that you think or espouse.

My SDM was sold because I was living in a unit that I owned at the time and could not use the SDM in my back yard. There was nothing wrong with the scope and yet you infer that there was. The build quality by Peter was to specs I asked for and it was very rigid and tracked better than expected. The only real down side was keeping the planet in the imaging pane. My sale of the scope was not related to what you have suggested here.

You make incorrect assertions and I wonder why anyone actually listens to your nonsense mate. You once before accused me of cutting holes in my SDM and this was utter crap. You have once again made assertions that are totally untrue. However you clearly are the expert and everyone should hail to your truths.

[RobF (Rob)]

Originally Posted by TrevorW

I know of one manufacturer who installs micro fans in there refractors to reduce the effects of thermals

Are you pulling our leg Trev?

[ausastronomer (John Bambury)]

Originally Posted by Paul Haese

Ah you clearly know more about all this than we do.

Anthony and I go back 5 years and that was when he first showed me active cooling. In point of fact he and I were discussing this very matter today when we met at Kapunda for a couple of hours. You have no idea what Anthony and I have discussed privately over the years and what design aspects we have thought about.

I have a peltier cooled C14 and had peltier cooling on the SDM too. I am well aware of the virtues of peltiers systems and have taken more data down that you think or espouse.

Well if you go back 5 years Paul you come up about 33 years short of me. I have been "visually" observing the planets with refractors and newtonians for 38 years and strangely enough never felt a need for any cooling assistance other than fans, on any of my scopes. Over the 38 years I have been observing the planets I have had some very memorable views, all without peltier cooling.

What part of, we are talking "VISUAL USE" in this thread are you not comprehending? It's pretty simple stuff really, for mine. You keep babbling about peltiers and active cooling but that is essentially an option for imagers only IMO. If you want to put peltiers on your imaging scope that's good. Your imaging scope happens to be a C14 which is a good choice. It's a poor choice for visual use because of a number of optical and physics issues. However, these do not manifest with imaging, so it is a good choice.

Regarding SDM 14. Simple truth is Paul you bought SDM #14 as a planetary imaging scope. Something it's inherent design does not allow it to excel at. It is a fantastic scope, but not for planetary imaging. I know a large number of experienced people who chuckled when they heard what you were buying and it's intended purpose. You can throw up a smokescreen as to the reasons why you bought it and why you sold it, but truth is I was laughing well before you ever took delivery of it.

Cheers,
John B

[Paul Haese]

Been into astronomy since I was 9 and am currently 46; I was referring to active cooling and planetary imaging. Not that it is a competition but you seem to think so John. Once again you assume far too much. Just open your mouth to put the other foot in if you like, no concern for me really.

Where are you getting this information about why I sold the SDM? I must have gone mad and now you know my mind. I told the truth about why I sold it, can't be plainer than that. It actually produced the best view of Jupiter than I or Anthony have ever seen through a scope at the first planetary imaging camp. I am sure he will tell you if you ask.


Think what you like John, but each time you make a statement that is wrong about me I am going to let you know that you have come to the incorrect conclusion.

I hope this has been as entertaining for everyone else as it has for John.

Sorry about the diversion for the original thread poster.

[ausastronomer (John Bambury)]

Originally Posted by Paul Haese

Sorry about the diversion for the original thread poster.

So you should be. You're the one that started dribbling about how fans were inadequate and active cooling was needed, when the thread was only ever focused on visual observing.

Last post on this thread BTW. Better things to do with my time.

[Paul Haese]

Originally Posted by ausastronomer

So you should be. You're the one that started dribbling about how fans were inadequate and active cooling was needed, when the thread was only ever focused on visual observing.

Last post on this thread BTW. Better things to do with my time.

Yes and I clearly needed to be addressed in the manner in which you have done. I must be so deserving of your scorn John.

[TrevorW]

Originally Posted by RobF

Are you pulling our leg Trev?

I suppose thermals was the wrong word more a case of reducing the temperature in an exclosed space as a way of bringing the glass to ambient as quickly as possible

concept

It features a cooling & internal seeing stabilization system:

• 9 little holes CNC machined on the conical section of frontal aluminum section (dew shield support).
• 9 little holes CNC machined on the conical section of rear aluminum section (focuser support).
• 3 internal electrical microfan (speed control provided).

[NorthernLight (Max)]

its like Schopenhauer vs Hegel... and a bit like the two grumpy guys on the balcony in the muppet show.
No offence gentlemen but I truely enjoyed reading.

[torana68 (Roger)]

so , um, if the dust has settled, forget the Tak and buy a really big good quality newtonian? sounds good to me bang for buck I cant see why I'd buy anything but a newtonian or variation of.
NB
a. no degree held (but working on it)
b. been doing it for years, probably more than you
c. "It" wont be expanded on.

[marki]

Originally Posted by torana68

so , um, if the dust has settled, forget the Tak and buy a really big good quality newtonian? sounds good to me bang for buck I cant see why I'd buy anything but a newtonian or variation of.
NB
a. no degree held (but working on it)
b. been doing it for years, probably more than you
c. "It" wont be expanded on.

Nah newts are rubbish, only good for visual but really who does that anymore? Even an average quality astrograph will show you more then the biggest newt on the best night through an eyepiece. A small refractor with a webcam will eat it alive.

a. several degree's held.
b. started in the womb and I am 107
c. I should hope so
d. I couldn't resist, Just jokes

Mark

[Daniel Mounsey]

Originally Posted by gb_astro

Mark he does have a shroud but claims the thermals pass right through it.

It looks like the standard rip-stop nylon type shroud.

gb.

This is my first post on this site. That is correct, the shroud does not protect against body currents, in fact even if you were wearing a thick down coat, it too, would not stop the heat currents. I would also like to thank gb for correcting the number of misunderstandings about my review.

Regards,
Daniel Mounsey

[torana68 (Roger)]

Originally Posted by Daniel Mounsey

This is my first post on this site. That is correct, the shroud does not protect against body currents .....
Regards,
Daniel Mounsey

...cant hide on the net can you Mr Mounsey, can you explain, how much do the body currents effect viewing , for me can that be in relation to a purely visual and home/hobby set up.
Is thre a material for shrouds tested to reduce the effect or should we stick to solid tubes where practical? (edit) or are body currents a better option in comparison to tube currents?
ta
Roger

[TrevorW]

http://www.cruxis.com/scope/mirrorcooling.htm

here guys knock yourself out and go collect some data

[Daniel Mounsey]

Originally Posted by torana68

...cant hide on the net can you Mr Mounsey, can you explain, how much do the body currents effect viewing , for me can that be in relation to a purely visual and home/hobby set up.
Is thre a material for shrouds tested to reduce the effect or should we stick to solid tubes where practical? (edit) or are body currents a better option in comparison to tube currents?
ta
Roger

Body currents could effect any telescope if the observer is not aware of it regarding their position relative to the telescope. Open truss dobs are by far the worst. Any type of current is degrading. To the best of my knowledge, there is no shroud available that stops or even slows down body currents. Perhaps someone may come out with a material but this issue is so unknown that even the ATM's who build their telescopes are not even aware of it. Ironic since it's devastating to images depending on the angle. I would definitely stick to solid tubes when practical. They hold collimation better as well.