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Skywatcher 200p Dob


awlfc

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First night out with my score last night. Decent breaks in the clouds and with the 10mm eyepiece that come with the scope I could see and find everything I pointed it at. But when i put my BST lenses in all i could see was my eye lashes. What am I doing wrong and why is the twist thing on the BST an extra focuser 

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16 minutes ago, awlfc said:

I bet you have some good skies in Texas. I'm in Liverpool UK. Loads of light pollution here. 

 

Some places in Texas still have dark skies but the big cities in Texas are no different from light polluted big cities everywhere. Since you have a 2x barlow already and the very nice 25mm Plossl, you are getting a 12.5mm equivalent when using the 25mm in the barlow. You might try an eyepiece in the 14-17mm range. Barlowed would give 7-8.5mm equivalent with more eye relief than the current 10mm Plossl. I find the Skywatcher 10mm is a good eyepiece but do not like the short eye relief and prefer larger eye lens with longer eye relief. Barlows increase eye relief unless they are telecentric design power amplifiers (focal extenders). A good 17mm is a nice jump down from 25mm and should have adequate eye relief as well. For a next jump in magnification, an 11mm would be good. In a barlow it would be a 5.5mm equivalent.

 

Three eyepieces and a barlow giving you 25mm, 17mm, 12.5mm, 11mm, 8.5mm, 5.5mm magnifications. Plus your 10mm as well and 5mm with the 10mm in a barlow.

if the barlow has the lens element that unscrews and can be screwed directly on the bottom of an eyepiece barrel, it will give 1.5x amplification.  So you have magnifications for the following focal lengths - 25, 17, 16.6, 12.5, 11.3, 11, 10, 8.5, 7.3, 6.6, 5.5, 5 millimeters

All out of 4 eyepieces (25, 17, 11, 10) and a 2x barlow 

 

Another option would be to get a Televue 2.5x Powermate. Three eyepieces (25mm, 17mm, 11mm), a 2x standard barlow with lens element that can be screwed directly on the eyepiece for 1.5x, and a 2.5x Powermate will give you a very large number of magnifications. Focal lengths of 25, 17, 16.6, 12.5, 11.3, 11, 10, 8.5, 7.3, 6.8, 5.5, 4.4 millimeters.

All those and you never have to use the Skywatcher 10mm Plossl to get any of that. You can tuck it away in a drawer.

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2 hours ago, awlfc said:

First night out with my score last night. Decent breaks in the clouds and with the 10mm eyepiece that come with the scope I could see and find everything I pointed it at. But when i put my BST lenses in all i could see was my eye lashes. What am I doing wrong and why is the twist thing on the BST an extra focuser 

The twist up eyecup is to help get your eye the correct distance from the lens. Set it up if you don't wear glasses, down if you do. 

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5 hours ago, awlfc said:

I bet you have some good skies in Texas. I'm in Liverpool UK. Loads of light pollution here. 

 

If I head a little further east or a couple of hours west, I can get darker skies.  Generally being well south of the jet stream, I have steady skies except when fronts pass through.  Being fairly far south also keeps the planets high enough to view every year.

I'm looking to buy a second/retirement home in the mountains of southeastern New Mexico where the dry air, altitude, and lack of light pollution make for some wonderful observing conditions.

Edited by Louis D
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5 hours ago, awlfc said:

First night out with my score last night. Decent breaks in the clouds and with the 10mm eyepiece that come with the scope I could see and find everything I pointed it at. But when i put my BST lenses in all i could see was my eye lashes. What am I doing wrong and why is the twist thing on the BST an extra focuser 

As Ricochet states above, that's an eye cup or eye guard to help position your eye at the right height and to block out stray light.  By the sounds of it, you're too close to the eye lens.  Try backing off a ways.  Approach the eyepiece from an inch away and look for the exit pupil when pointed at the moon to make it easy to find.  As you get closer, you should see the view expand until you can see the field stop.  Don't push in any closer or the view will start blacking out.  Twist up the eye cup until it lightly touches your face.  Now, all you have to do is lean in until you feel the eye cup the next time you use that eyepiece.

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21 hours ago, Vondragonnoggin said:

Some places in Texas still have dark skies but the big cities in Texas are no different from light polluted big cities everywhere. Since you have a 2x barlow already and the very nice 25mm Plossl, you are getting a 12.5mm equivalent when using the 25mm in the barlow. You might try an eyepiece in the 14-17mm range. Barlowed would give 7-8.5mm equivalent with more eye relief than the current 10mm Plossl. I find the Skywatcher 10mm is a good eyepiece but do not like the short eye relief and prefer larger eye lens with longer eye relief. Barlows increase eye relief unless they are telecentric design power amplifiers (focal extenders). A good 17mm is a nice jump down from 25mm and should have adequate eye relief as well. For a next jump in magnification, an 11mm would be good. In a barlow it would be a 5.5mm equivalent.

 

Three eyepieces and a barlow giving you 25mm, 17mm, 12.5mm, 11mm, 8.5mm, 5.5mm magnifications. Plus your 10mm as well and 5mm with the 10mm in a barlow.

if the barlow has the lens element that unscrews and can be screwed directly on the bottom of an eyepiece barrel, it will give 1.5x amplification.  So you have magnifications for the following focal lengths - 25, 17, 16.6, 12.5, 11.3, 11, 10, 8.5, 7.3, 6.6, 5.5, 5 millimeters

All out of 4 eyepieces (25, 17, 11, 10) and a 2x barlow 

 

Another option would be to get a Televue 2.5x Powermate. Three eyepieces (25mm, 17mm, 11mm), a 2x standard barlow with lens element that can be screwed directly on the eyepiece for 1.5x, and a 2.5x Powermate will give you a very large number of magnifications. Focal lengths of 25, 17, 16.6, 12.5, 11.3, 11, 10, 8.5, 7.3, 6.8, 5.5, 4.4 millimeters.

All those and you never have to use the Skywatcher 10mm Plossl to get any of that. You can tuck it away in a drawer.

Ive copied and paste that into my notes. I'll start buying a few extras each pay day.

 

Last night it all come together and had some amazing views of Jupiter I could see the colour and band across it. My views of the moon blew me away. Just randomly pointing the scope around the sky and seeing thousands of stars. 

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On 14/06/2019 at 21:27, Louis D said:

Actually, I've always thought Texans and Australians shared a lot in common, vis-a-vis rugged individualism.

Very laid back down under, though things gradually changing with increase in immigration 

We are now very much a multi-cultural country

Where I am, I have fairly clear skies, and shielded from light pollution, by hills around us

You ever make it down this way, say hi

The attached pic attempted to take about an month ago

Unfortunately smart phones do not like like poor light setting

Was supposed to be quarter moon, with conjunction with Venus, and Jupiter, fraction above Jupiter

Taken around 4-30am, as leaving home for work

John

  

Conjunction Venus and Moon.jpg

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Here's a couple of handheld sky photos I took with my Canon DSLR from the parking lot of my hotel on the edge of Ruidoso last fall.  These are straight out of the camera with no processing other than resizing for upload.

1885826498_RuidosoNM1.thumb.jpg.fe4e268ca53e2ce9f89f69142f3c1658.jpg

1760417923_RuidosoNM2.thumb.jpg.d1a0eb43cf0c6cd5a885290b9488e630.jpg

It was surprisingly dark for being that close to a metro area of 21,000 people.  I am looking to get a vacation home about 40 miles away from Ruidoso which should have next to no light pollution.

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6 minutes ago, awlfc said:

Is the an eyepiece I can buy to make the image i see the right way up

Not as such - but you can get an "erecting prism", which will do that (and fix left-to-right, too). But I've never used one - mostly seem to be pitched at terrestrial use rather than astronomy.

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31 minutes ago, discardedastro said:

Not as such - but you can get an "erecting prism", which will do that (and fix left-to-right, too). But I've never used one - mostly seem to be pitched at terrestrial use rather than astronomy.

That won't work with a Newtonian as there will not be enough focuser travel to achieve focus. 

I wouldn't worry about getting the image the right way up, you soon get used to moving the scope and when viewing astronomical objects the orientation doesn't matter. 

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If it bothers you that much, you could try looking into the eyepiece from the other side of the tube which should make things right side up at least.  Of course, your head will be partially upside-down.

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11 hours ago, Louis D said:

If it bothers you that much, you could try looking into the eyepiece from the other side of the tube which should make things right side up

Yes, point your butt toward your target. That improves the experience of observing terrestrial views through a Newtonian. Some targets find this offensive.

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