Author Topic: Which would you choose?  (Read 165 times)

Larry Hopkins

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Which would you choose?
« on: December 27, 2017, 02:25:15 PM »
Hey guys, I now have an Orion Astroview 90mm EQ, and I need some educated opinions. The focal length on this scope is 910mm, and it has a 90mm aperture. If my calculations are correct, I shouldn't try to push beyond 180x for good viewing. I have 3 eyepieces: a 25mm, 15mm, and a 10mm. The 25mm yields 36x, the 15mm 60x, and the 10mm 91x. I can already get to 180x with the 10mm using a 2x Barlow, but the experience is less than pleasant due to the horrible eye relief on the 10mm eyepiece. I feel like I'm trying to stick the eyepiece into my brain when I use it.

So, here is my question: If you were trying to get to 180x, and you could do it by using the 25mm eyepiece with a 5x Barlow, or the 15mm with a 3x Barlow, which would you do? The eye relief on the 15mm eyepiece is good, but the 25mm is better. I guess what I am really asking is is there a factor that gets worse with a Barlow the higher (or longer FL) you go? Thanks for the input.



massgisttesci

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Re: Which would you choose?
« Reply #1 on: December 27, 2017, 11:40:04 PM »
Maybe if you thought about it in a different way. If you wanted 180 power, you could use a 5mm eyepiece.

A 10mm eyepiece with a 2x barlow will give you more eye relief than a 5mm. So, I might use the 10mm with the barlow, if that's all I had.On my scopes, I would use the 5mm and not put another lens in the optical path. I just don't care for the barlow. Other people may like them.

knigabretta

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Re: Which would you choose?
« Reply #2 on: December 30, 2017, 05:45:34 AM »
Quote
Maybe if you thought about it in a different way. If you wanted 180 power, you could use a 5mm eyepiece.

A 10mm eyepiece with a 2x barlow will give you more eye relief than a 5mm. So, I might use the 10mm with the barlow, if that's all I had.On my scopes, I would use the 5mm and not put another lens in the optical path. I just don't care for the barlow. Other people may like them.

I thought about that, but figured that the eye relief on the 5mm would be worse than the 10mm, which is already bad (to me at least). I tend to like longer eye reliefs. Is there a 5mm with a long eye relief?

headsbigwardsubs

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Re: Which would you choose?
« Reply #3 on: January 04, 2018, 03:06:57 AM »
If you have the $$$, this Tele Vue 5mm Nagler Type 6 eyepiece has 12mm of Eye Relief and 82 degrees Apparent Field of View: https://www.optcorp....piece-1-25.html

Tony Patton

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Re: Which would you choose?
« Reply #4 on: January 08, 2018, 07:49:08 PM »
Quote
If you have the $$$, this Tele Vue 5mm Nagler Type 6 eyepiece has 12mm of Eye Relief and 82 degrees Apparent Field of View: https://www.optcorp....piece-1-25.html

Yea......... that eyepiece costs as much as my telescope, so I think I will be going with plan b. Thank you for the option though.

Jessie Forbes

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Re: Which would you choose?
« Reply #5 on: January 13, 2018, 03:40:30 AM »
I think 180x is a bit much for this scope, 150x is about the upper limit in most conditions, with around 110x for average conditions. A 6mm eyepiece would be about max, or a 12mm with 2x Barlow. You will not see any more detail at a higher magnification in most cases. Only on a excellent night will going higher be of use, and only if it has very good optics.

coatiorachin

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Re: Which would you choose?
« Reply #6 on: January 14, 2018, 03:03:10 AM »
Quote
Quote

Maybe if you thought about it in a different way. If you wanted 180 power, you could use a 5mm eyepiece.

A 10mm eyepiece with a 2x barlow will give you more eye relief than a 5mm. So, I might use the 10mm with the barlow, if that's all I had.On my scopes, I would use the 5mm and not put another lens in the optical path. I just don't care for the barlow. Other people may like them.

I thought about that, but figured that the eye relief on the 5mm would be worse than the 10mm, which is already bad (to me at least). I tend to like longer eye reliefs. Is there a 5mm with a long eye relief?
An Explore Scientific 4.7mm 82° would give you ~194X, with 13.6mm eye relief -- which I find to be completely comfortable, when using it on my ES 102mm f/7 APO, which has incredibly sharp optics. The ES 6.7mm 82° would give you ~136X, with 15.7mm eye relief... which as Richard Whalen points out, might serve your hopes far better, regarding clarity and real-world usability.

https://explorescien...series-eyepiece

William Mendoza

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Re: Which would you choose?
« Reply #7 on: January 18, 2018, 07:13:32 AM »
Quote
I think 180x is a bit much for this scope, 150x is about the upper limit in most conditions, with around 110x for average conditions. A 6mm eyepiece would be about max, or a 12mm with 2x Barlow. You will not see any more detail at a higher magnification in most cases. Only on a excellent night will going higher be of use, and only if it has very good optics.

I can get around 108x with the 25mm with a 3x Barlow, but I can already do 120x with my 15mm and 2x Barlow. Do you think that I should just stick with that? Or do you think the extra eye relief and fov is worth buying a 3x Barlow to use with the 25mm? Btw, my 2x Barlow doubles as a 1.5 when the lens is unscrewed from the barrel of the barlow and attached directly to the end of the eyepiece.

My current setup allows different configurations for 36x, 54x, 60x, 72x, 90x, 120x, 136x, and 182x.

russnappditcva

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Re: Which would you choose?
« Reply #8 on: January 21, 2018, 12:25:27 PM »
You will only get less eye relief if you go to a shorter focal length eyepiece AND stay with the same eyepiece design.

TMB planetary eyepieces give plossl like views for about $45.00 a pop, with lots of eye relief.
Others like paradigm eyepieces I think they go for a little more used. You could get a 5mm or 6mm one of these.

A 2x barlow may extend the eye relief of your 10mm a little. But not a quantum leap.

Like the others said, 180 might be pushing your scope. So if you buy a fixed focal length eyepiece at 5mm.
You may never use it.

Besides image quality another issue is vibration and tracking. More power means vibrations will be more apparent,
and tracking will be more difficult unless you have a gem or a tracking mount.

I have not used 3x or 5x barlows so I cannot comment on their quality or caveats.

Timothy Moody

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Re: Which would you choose?
« Reply #9 on: January 30, 2018, 08:38:33 AM »
Quote
You will only get less eye relief if you go to a shorter focal length eyepiece AND stay with the same eyepiece design.

TMB planetary eyepieces give plossl like views for about $45.00 a pop, with lots of eye relief.
Others like paradigm eyepieces I think they go for a little more used. You could get a 5mm or 6mm one of these.

A 2x barlow may extend the eye relief of your 10mm a little. But not a quantum leap.

I have not used 3x or 5x barlows so I cannot comment on their quality or caveats.

Thank you

perpemucho

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Re: Which would you choose?
« Reply #10 on: January 31, 2018, 12:58:11 AM »
I prefer using barlows with a Newtonian, not so much with a refractor. There's just too much sticking up from the diagonal. Single eyepieces seem to work better for me. The BST eyepieces from Agena Astro are $55 each, have a 58 degree AFOV, and 16mm of eye-relief. They have many sizes though some are out of stock. The Meade 5000 HD-60's and Celestron X-Cel LX are great, too, for not much more. They are similar in AFOV and eye relief. There are other brands as well that are similar. These are comfortable eyepieces with large eye lenses. Check them out.

gladinises

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Re: Which would you choose?
« Reply #11 on: January 31, 2018, 08:22:58 AM »
151x for cheap.  These get surprisingly good reviews from experienced observers.
http://m.ebay.com/it...f5761%7Ciid%3A8
The Orion Astroview 90 looks like a really nice scope.  I check it out everytime I am at the Orion site.

penliipamex

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Re: Which would you choose?
« Reply #12 on: February 02, 2018, 06:18:43 PM »
Quote
Hey guys, I now have an Orion Astroview 90mm EQ, and I need some educated opinions. The focal length on this scope is 910mm, and it has a 90mm aperture. If my calculations are correct, I shouldn't try to push beyond 180x for good viewing. I have 3 eyepieces: a 25mm, 15mm, and a 10mm. The 25mm yields 36x, the 15mm 60x, and the 10mm 91x. I can already get to 180x with the 10mm using a 2x Barlow, but the experience is less than pleasant due to the horrible eye relief on the 10mm eyepiece. I feel like I'm trying to stick the eyepiece into my brain when I use it.

So, here is my question: If you were trying to get to 180x, and you could do it by using the 25mm eyepiece with a 5x Barlow, or the 15mm with a 3x Barlow, which would you do? The eye relief on the 15mm eyepiece is good, but the 25mm is better. I guess what I am really asking is is there a factor that gets worse with a Barlow the higher (or longer FL) you go? Thanks for the input.
Using the typical 2X aperture in MM, 180 would be the right target for top mag for your scope.  Likely you can push beyond that on the moon if the atmospheric conditions will allow.  But 180X would be a good top target.

Quote

<p class="citation">Garyth64, on 15 Aug 2017 - 01:24 AM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=8049824" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="Garyth64" data-cid="8049824" data-time="1502753051">
Maybe if you thought about it in a different way. If you wanted 180 power, you could use a 5mm eyepiece.

A 10mm eyepiece with a 2x barlow will give you more eye relief than a 5mm. So, I might use the 10mm with the barlow, if that's all I had.On my scopes, I would use the 5mm and not put another lens in the optical path. I just don't care for the barlow. Other people may like them.
I thought about that, but figured that the eye relief on the 5mm would be worse than the 10mm, which is already bad (to me at least). I tend to like longer eye reliefs. Is there a 5mm with a long eye relief?

[/quote]
If you have enough money to spend you can find almost any combination you like. However I don't see that you have provided a budget per eyepiece or a budget to fill out the range so I will ignore cost.<p class="citation">Msged2007, on 15 Aug 2017 - 02:27 AM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=8049956" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="Msged2007" data-cid="8049956" data-time="1502756854">

<p class="citation">Richard Whalen, on 15 Aug 2017 - 01:58 AM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=8049891" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="Richard Whalen" data-cid="8049891" data-time="1502755128">
I think 180x is a bit much for this scope, 150x is about the upper limit in most conditions, with around 110x for average conditions. A 6mm eyepiece would be about max, or a 12mm with 2x Barlow. You will not see any more detail at a higher magnification in most cases. Only on a excellent night will going higher be of use, and only if it has very good optics.
[/quote]
I can get around 108x with the 25mm with a 3x Barlow, but I can already do 120x with my 15mm and 2x Barlow. Do you think that I should just stick with that? Or do you think the extra eye relief and fov is worth buying a 3x Barlow to use with the 25mm? Btw, my 2x Barlow doubles as a 1.5 when the lens is unscrewed from the barrel of the barlow and attached directly to the end of the eyepiece.

My current setup allows different configurations for 36x, 54x, 60x, 72x, 90x, 120x, 136x, and 182x.

[/quote]

I have used 2X and 3X barlows for visual astronomy.  Have never tried a 5X barlow for visual. I have been told they are primarily for AP. In a 910 mm FL scope I would not plan to go over 2X.Sounds like you have a nice range of magnifications.  Somewhat of a large gap between 136 and 182. I would want to put something in there.I don't have these problems since I moved to Zoom eyepieces.  Now my strategy for each scope is:

Lowest power/widest view eyepiece that will work. In a 1.25" focuser that is usually a 32 mm Plossl
Midrange is handled by my 24 mm to 8 mm zoom. In your scope that would be 38X to 113X and all magnifications in between
High would be handled by zoom plus 2X barlow. In your scope that would be 76 to 223X and everything in between.
So 2 eyepieces and a 2X barlow is all that is needed.  No gaps from 38X to 223X.  you might get to 223 on the moon on a very good night. You might get to 200X on Jupiter or Saturn on a very good night.Lower Budget Zoom – Celestron 8-24 mm – This was my first zoom. $65 – Good quality and very versatile. If your eyepiece kit is made up of RKE, Modified Achromat, Kellner and Plossl type eyepeices and your budget is around $30 to $75 per eyepiece then this would probably be a good one for you to consider as it will replace 3-4 single FL eyepieces. Review link is provided below.http://agenaastro.co...m-eyepiece.html
Higher Budget Premium Zoom – I have since upgraded to the Baader Hyperion 8-24 mm Zoom. If your eyepiece budget is $120 per eyepiece or higher then consider the highly recommend Baader Hyperion Mark IV Click Stop 8-24 Zoom as it will replace 3-4 single FL eyepieces. $280. You can get a package for $380 with matching barlow. Review of the earlier Mark III is provided below.http://agenaastro.co...ce-2454826.htmlI never expected the zoom eyepiece to become my primary eyepiece, but it has.
The Celestron is good and comparable to my Plossl eyepieces but the Baader Hyperion is great and comparable to my Explore Scientific eyepieces
Watching doubles split as I rotate the barrel is wonderful
One filter serves over a wide range of magnifications, no screwing and unscrewing to try other eyepieces
Moving smoothly from and between small changes in magnification helps when seeing is not the best
Sharing the view with others is easier, especially in my manual tracking Dob - I can hand it over at low mag so it stays in the view longer, and then have them zoom back in to whatever magnification works best for them rather than for me.
Kids love the zoom
My eyepiece case has been greatly simplified

If you prefer single focal length, wider AFOV eyepieces then let me suggest the Explore Scientific 68 and 82 degree series.
I have two of the 82s and like them a lot. Reviews show them to be very close to eyepieces costing much more.http://agenaastro.co...scientific.htmlNaturally your smileage will vary.Baader Hyperian Mark III Clickstop zoom reviewhttp://www.weasner.c...iece/index.html
Baader Hyperion Mark IV - The current modelhttps://www.cloudyni...-zoom-eyepiece/
Baader Zoom Vs Fixed Eyepieces - This will open your eyeshttp://www.cloudynig...m-vs-fixed-eps/
zoom eyepiece review – Includes the Celestron zoomhttp://www.chuckhawk...m_eyepieces.htm
Celestron 8-24 Zoomhttp://www.cloudynig...celestron +zoomhttp://www.cloudynig...celestron +zoomhttp://www.cloudynig...del-93230-r2106

gladinises

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Re: Which would you choose?
« Reply #13 on: February 09, 2018, 09:05:18 AM »
Quote
Quote

I think 180x is a bit much for this scope, 150x is about the upper limit in most conditions, with around 110x for average conditions. A 6mm eyepiece would be about max, or a 12mm with 2x Barlow. You will not see any more detail at a higher magnification in most cases. Only on a excellent night will going higher be of use, and only if it has very good optics.

I can get around 108x with the 25mm with a 3x Barlow, but I can already do 120ite and look at their EP selx with my 15mm and 2x Barlow. Do you think that I should just stick with that? Or do you think the extra eye relief and fov is worth buying a 3x Barlow to use with the 25mm? Btw, my 2x Barlow doubles as a 1.5 when the lens is unscrewed from the barrel of the barlow and attached directly to the end of the eyepiece.

My current setup allows different configurations for 36x, 54x, 60x, 72x, 90x, 120x, 136x, and 182x.
I think introducing another piece of glass is always a recipe for disappointment. Stop focusing on the barlows and start thinking about the quality of the glass you're using. It's bears repeating: The ES 4.7 or 6.7MM EP's are the ticket, BUT....if that's too far out of your range, consider going to Orion's website and look at their offerings for EP's. Their price/quality ratio is very good. But you also seem to be barking up the wrong tree here. It's not about power. That's fool's gold. The 10MM by itself should suffice but only on the better nights. The 15MM should be in the neighborhood of the sweet spot for that scope. It's not a twelve inch dob, you know. Follow the strengths of your scope, don't try to make it be something it's not. Just some friendly advice...

STARKID2U