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Topics - trapoutampub

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I have an Orion xx16g dob that has an 1800 mm focal length and an F ratio of 4.4. I have a set of older Meade series 5000 UWA and SWA eyepieces. I'm disappointed by the image brightness, even at 30-34mm eyepiece focal length. I expected that with 16 in of aperture that I would get very bright starfield images with these eyepieces. My optics are clean and free of dew. I'm just trying to understand why I don't have brighter images even at lower magnification. I don't think logically that FOV should impact brightness at a given eyepiece focal length but can anyone tell me for sure? Thanks!

Reflectors Telescopes Forum / SKY COMMANDER PROS & CONS
« on: December 28, 2017, 10:48:06 PM »
Thinking about a Sky Commander to put on a Zhumell 12" dob. Has anyone had a chance to use one? I thought about Argo Navis but to much money. Appreciate feedback on the Sky Commander. ThanksBill

Reflectors Telescopes Forum / I'm really torn about my dream scope.
« on: December 27, 2017, 07:01:41 PM »
I've been thinking and plotting and scheming and over-analyzing my dream telescope purchase - big-ish dob from Teeter.

After a lot of math and pros and cons, I've narrowed it down to two contenders, both with Lightholder optics since the atmospheric seeing conditions where I live do not justify Zambuto mirrors.16" F/4
- 21.86% central obstruction
- 61" zenith eyepiece height (would not need a ladder!!)
- $7,600 base cost

- Least expensive
- No ladder needed
- Nice bright exit pupil (5.25mm) and 1.28 degree FOV with 21 Ethos, which will make it perfect for filtering my favorite object of all time: M42.
- Will not need 31mm Nagler (saves $650)

- Ok, but not great central obstruction
- Will be below my exit pupil sweet spot of 1.7mm @ my location's atmospheric limits (~300x), but still above my minimum of 1mm
- Using filters or binoviewer will result in dimmer images and/or limiting magnification and thus the reach of the scope
- More gain needed for planetary imaging20" F/4.5
- 17.5% central obstruction (!!)
- 87" zenith eyepiece height (definitely need a ladder )
- $9,475 base cost

- Very small central obstruction, maximum contrast for planets and faint objects (contrast is important, since I'm magnification limited where I live)
- Will give the brightest views at a given magnification, which will be great for binoviewing, using filters, and really reaching for small planetaries and galaxies
- Will be just at my exit pupil sweet spot of 1.7mm @ my location's atmospheric limits (~300x)
- Adding the 31mm Nagler will give me a wonderfully bright exit pupil (6.89 mm) for filtering M42 with.
- Less gain needed for planetary imaging, allowing for shorter exposures and sharper captures
- Brighter, fuller globular clusters

- Most expensive
- Needs a ladder
- Sub 1 degree FOV in 21 Ethos, will need 31mm Nagler to see larger objects like double cluster (+$650)I've done the math on everything in between (16" F/4.5, 16" F/5, 18" F/4, 18" F/4.5 etc) and all of those other focal ratios are just "bad" compromises and have no major selling point for me. The 16" F/4 is tempting *mostly* because of its eyepiece height. I don't mind the higher cost of the 20" since it will translate to optical performance. But I can't avoid a ladder with it. Any other scope in between still requires a ladder, OR has a larger central obstruction, and is way more expensive.

I own an 8" SCT now, so the 16" is going to be a major upgrade regardless. But I don't know what I'd regret more: not having the contrast, raw light gathering power, and reach of the 20" or having to move a ladder around just to look through it. Very torn. Anyone have any words of wisdom?

Mounts Questions & Expirience / Vixen SXW with no Starbook.
« on: December 26, 2017, 11:19:38 PM »
Hello All,
I only recently purchased Vixen SXW bracket without a Starbook and was interested if I could control it with no Starbook.  Everything I have read seems to say it is only useable with all the Starbook so it looks like I may've got a raw deal.
I read on the discussion that I can alter the bracket to have a Celestron control... is that a good option or should I attempt to seek out a Starbook for my bracket?

Beginners Forum / help selecting telescope
« on: December 25, 2017, 10:28:37 AM »
I would like to purchase a telescope and would like some feedback/suggestions.  Portability is the biggest issue.  I've considered the celestron evolution 6 or 8 (internal battery, wi fi), 120mm refractor and 8 dob.  My viewing area choices are dark heavens but lots of trees so I will need to carry the range and setup - also being able to view pretty vertically because of trees is vital.  I'm not as agile as I was and 40 pounds is really pushing it.  I'm torn between focusing primarily on planets vs seeing as much as I can.  I realize I've recorded very different choices.  My first consideration was that the dob but am concerned about ability to maneuver and set up.  Then went to refractor but have been attracted back to evolutions but concerned about portability.  I'm willing to spend up to $1500 for the extent.  Suggestions very welcome.  Thanks.  I've learned a lot from cloudy nights.

Eyepieces Questions & Recommendations / Nearly wrote off my 23mm Vite...
« on: December 25, 2017, 09:56:13 AM »
Not believing I cleaned the surface of the eye lens along with my T shirt...

Oh No!  The coatings are ruined!

All that money down the drain. 

So - using a few 1/10 micron diamond paste and a polishing pad I removed the remainder on both sides.

Good as new and appears to function perfectly.

Phew!  This was scary...

Beginners Forum / Stellarium for a newbee
« on: December 24, 2017, 12:02:44 AM »
It's a moist and cloudy night here, so I just downloaded Stellarium.  WOW, what an wonderful piece of free software.I have figured out the basic controls and the way to eliminate the overwhelming amount of information on each object/star, also the best way to store my settings, that sort of thing.So how would you experienced astronomers suggest using it for somebody new to astronomy?I definitely think it will be more powerful and simple than using Sky Safari, no freezing along with a bigger display, and it will help me get to know the basic constellations considerably easier.Any additional thoughts for a newbee?Exactly what's included with hooking it up to my scope?  Or is that something that I shouldn't bother using for now?Appreciate any input you can offer.

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