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Messages - olexecin

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106
Quote
hardware will get fast enough to speed up the frame rate so as to nearly eliminate observable air turbulence effects (for planetary and lunar viewing, this may well be possible right now).
No matter how high your frame rate is, you can't eliminate turbulence. You can get it high enough, that you can take enough pictures to capture the occasional lucky one where the image is sharp, but you then need to find this needle in the haystack of hundreds or thousands of frames.

To eliminate seeing, you need adaptive optics. Here I see some possibilities for real progress in the coming years, as computers and cameras (you need a camera to monitor the image the scope is seeing and a computer to analyze it) get ever smaller and ever more powerful. Clear skies!
Thomas, Denmark

107
Beginners Forum / Re: Star Test.
« on: December 29, 2017, 04:59:19 PM »
1st you should use at least the same fl eyepiece as the f-ratio of the scope, use a 6mm for an f6 scope...

defocus inward measure travel, the defocus outward the same amount of travel. look for 2ndry shadow break out size on both sides of focus.

here's a really bad mirror.

https://www.youtube....h?v=tAD-2r6gW9A

here's one that's about 1/4~ over.

https://www.youtube....h?v=MFmFpuST67M

here's a very well corrected mirror, just need to keep the cell phone over the exit pupil so skip to the middle of the vid

https://www.youtube....h?v=H8H4622hBlQ

108
Beginners Forum / Re: Orion autotracker telescopes and mount
« on: December 29, 2017, 05:57:18 AM »
That particular 4.5" Newtonian has a focal-length of 500mm, and at f/4.4; the "StarBlast" variant: 450mm(f/4).

It looks like fun, but I'd strive and add another $230 to get this one instead...

http://www.telescope...15/p/113916.uts

109
Eyepieces Questions & Recommendations / Re: ES62 5.5mm vs. DeLite 5mm?
« on: December 29, 2017, 04:32:51 AM »
There is actually a whole thread about the ES 62 degree line, but the general consensus is they are similar to Meade’s 5000 plossl line of eyepieces.

That being said the ES is not quite the full 62 degrees and only has ~ 13mm of ER. The Delite on the other hand has the full 62 degrees and 20mm of ER. There are a number of good reviews of the ES 5.5 so I don’t think you’d be disappointed.

If you’re an eye glass wearer who is dead set on the full 62 degrees you’d want the Delite, if you’re happy without glasses and close but not quite 62 degrees works for you, you should be fine with the ES.

On the last page of the ES 62 thread Myriam has an extensive review of the ES 5.5.

https://www.cloudyni...ee-line/page-16

110
I have the 28mm and 16mm 68°. I love them, tack sharp eyepieces.

Barlowed, the 16mm becomes an 8mm with a little more eye relief. Thus, you obtain a very nice spacing: 16-8-5.5mm.

Can't speak for the 14mm UWA, but barlowed you get a 14-7-5.5mm range, slightly less optimal than the previous one. Ah, the 16mm is smaller and lighter, if this is important for you.

111
ATM, Optics and DIY Forum / Re: Protostar Defunct?
« on: December 29, 2017, 03:38:31 AM »
Got some flocking board last week after about three weeks wait.

112
ATM, Optics and DIY Forum / Dobsonian binocular observing chair
« on: December 29, 2017, 12:35:12 AM »
When I was researching to build a binocular observing chair I found that there were few designs to build upon. So I did what we all do and took a bit of this and a bit of that and came up with this. Hopefully it can be an inspiration for someone else to build upon. I wanted it to be portable, strong, light, dobsonian, made of wood and capable of being used as a regular reclining chair when at star parties and the like. I call it my Quantum Gravity Chair ..... just because. It moves smooth like butter and holds the 15x70's so stable that scanning the skies are solid and effortless. It can be pointed from 5 degrees above the horizon to zenith and locked at any angle in between.

113
Eyepieces Questions & Recommendations / TeleVue eyepieces
« on: December 28, 2017, 11:42:35 AM »
OK guys, I had a look at the TeleVue site and couldn't see a quick run down on this. Excuse me if this has been asked before..

but what is the difference between the different types of eyepieces that TeleVue offers?

Radian?

Delos?

Ethos?

Panoptic?

Nagler?

Why would I choose One design over the other design(s)? Strengths and weaknesses of either design?

I have a 900mm f9 scope (SkyWatcher Equinox 102 APO) and a Bintel (GSO rebrand) 8" f5 Newtonian (hasn't seen first light yet).

I like both planetary and DSO observing.

Your thoughts are appreciated.

Cheers,

Dave

114
Well...I have an intermittent connection on my board at the power jack for my ZEQ.

Is it possible you might have accidentally stressed the junction Bob? (usually it's the cable that fails, but not always, sometimes the receptacle solder joint gets yanked and goes to a full open-circuit condition, or an intermittent like mine.)

I'm sure iOptron will sort it out for you.

115
Beginners Forum / Re: This is why I wanted a telescope…
« on: December 27, 2017, 11:34:52 AM »
That is what it's all about

116
Beginners Forum / Re: Star Hopping Question
« on: December 27, 2017, 12:08:28 AM »
I am unfamiliar with this particular publication however it's pretty simple to make cable rings that represent the finderscope field of view or just cut a circle out of a piece of clear plastic (may hold the circle shape and not be so difficult to find in the dark once you drop it).  I use the Pocket Sky Atlas and there is a template in front for different size circles but I do not know where else you'd find one.  Probably somebody here has a source and will chime in soon.  Otherwise I am not aware of anybody making them commercially.

117
ATM, Optics and DIY Forum / Re: Best source of mirror kit for the price?
« on: December 26, 2017, 06:55:32 PM »
cool.

Perform f6, f7.5 is no pleasure, you'll overcorrect it before you blink your eye.  Even at f6 you will quickly overshoot it.

I'd even suggest f5 if you don't have a scope for this


Newport glass will generate whatever curve you need.  And you'll be able to get a thinner clean than a standard old standard of 1:6 ratio.

Getting them to generate the curve isa large benefit.  So all you've got to do is a moist or two of 120grit to brake in the instrument
I'd make the tool instead of wasting glass and paying for this to be generated to a matching curve.

118
Beginners Forum / Deep sky list planning advice
« on: December 24, 2017, 07:40:04 PM »
Ok so I have been to a dark skies sites with my 8 inch inteliscope dobsonion.  I am fairly new to the hobby (two years).  Next month I will be moving into the darkest skies I have ever been around with my range.  Bortle dark skies 2-3 I think.  It's a fairly long drive from my house several hours.  So I wish to make up a list of objects and have a plan because this opportunity does come together to often.  Any information on where to start or plan wpuld greatly be appreciated.

119
Beginners Forum / Re: Why? What is averted vision?
« on: December 24, 2017, 03:58:09 PM »
Averted vision is if you do not look driectly in an object.  I think there are 2 reasons.
First is that looking directly at an object signifies that the image falls on the middle of the trunk of the eye and that's where the blind spot is.

The other (I think) is that the central portion of the eye has the colour sensitive beams and these require a degree of brightness to see anything.

So a dim thing looked at directly can be difficult to "watch".

The rods are (I think) not fundamental and are more sensitive but they aren't colour.  So to bring these into play you need to look a bit off to one side and then they are used.  So a dimmer thing becomes "clear" but it's gray and should you try to look at it then it disappears.

120
General Astronomy & Observing / WHAT WOULD YOU DO SUGGESTIONS NEEDED
« on: December 23, 2017, 11:51:49 PM »
I've been in astronomy for quite awhile now.  Due to back and hip problems I have had to sell all of my astro gear.  I've Had reflectors, refractors and
SCTs and age is also a factor.  I've a real good place in my backyard to observe.  I've 2??1/2 acres no neighbors in 800 feet and a cement slab
Surrounded by a tarp enclosure of 20 foot square.  I want to find something light weight I know I can handle.  I am looking at a set of Oberwerk
25 X 100mm binoculars and a Meade Infinity 102mm refractor.  I love to look in Galaxies, Nebulas, Open and globular clusters, and DSO observing.
I'm not into planets that much.These to things are within my budget and require no ability to utilize.  I would like to have opinions on these two things as how they compete against each other for your kind on viewing I love to perform.  I know that its a loaded question that your thoughts greatly appreciated.  Thanks

Bill

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