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Do you use an erecting prism diagonal?


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 For lunar observation do you find an erecting diagonal preferable?

I'm fairly new to astronomy and lunar observation appeals a lot. Just wondering how more experienced observers do it.

Thanks, Patrick 

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49 minutes ago, PatrickO said:

 For lunar observation do you find an erecting diagonal preferable?

I'm fairly new to astronomy and lunar observation appeals a lot. Just wondering how more experienced observers do it.

Thanks, Patrick 

I think a few do, who are sensitive to orientation but I think most prefer the higher quality of a mirror or standard prism (ie not correct orientation). The corrected prisms generally do show artefacts on bright stars and some degradation at higher powers, so personally I don’t use them. There are lunar maps which show left/right reversed views to make identification easier, or software apps that do the same so it is a manageable issue from that perspective.

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I don't  tend to use one on the moon. I have kept the one that came with the ST80 for terrestrial viewing. I think being someone who started my observing journey with a Newtonian I am used to an upside down Moon 😁.

Stu is right a good quality diagonal will give a better view and books or software can give you the information you need.

Cheers

Ian

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I'm in the same camp as @Stu on this one. High quality standard prism or mirror diagonal for me and I accept the L&R reversed views. 

Stellarium and Cartes du Ciel have fairly easy to use facilities to flip the image E&W / N&S / both and I'm sure other such tools have a similar function somewhere.

 

Edited by John
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Rather than correct the image for lunar, I purchased the  Duplex Moon Atlas which has both refractor and reflector displays. Makes identifying features a doddle. 

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Baader T2 amici prism diagonal is as good - or better - quality than most diagonals out there and shows a non-reversed image. On a bright star at high magnifications you can just perceive a tiny spike if you look for it, but it’s a non-issue. So for those who prefer a ‘normal’ view of the Moon, yet don’t want to compromise the view, the Baader comes highly recommended. 

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I use the Baader clicklock and Baader Zeiss T2 prism diagonals in my refractors, for the best image I can get, and wrestle with Lunar orientation...:smiley:

Edited by Saganite
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Nice choices Steve.

I tend to use the amici when I’m panning around the surface, and looking at features on a wider scale. I use binoviewer and Nagler 13s for an expansive view, and I do prefer a left-right orientation for this. Think it’s because I studied lunar maps from a young age and still find it more natural. Then for close up lunar details I more often use a right-left prism or mirror. It just involves a little thought before I set up.
To be honest, everything looks so great on the Moon - including pretty much every eyepiece, telescope and diagonal I’ve ever used - that it’s not the best target for distinguishing critical performance differences. So for those who prefer correct orientation on the Moon, a quality amici is well worth considering. 

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I don't worry about orientation as long as I have the sharpest image and finest detail.

I use a 45° erecting prism on my 60mm for birdwatching. Makes sense to have things the right way round.

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+1 for a “right way up right way round” view being quite satisfying at lower magnifications and especially full disk magnifications. For me it preserves a nice relationship to naked eye views, binocular views, globes, and/or everyday images of the moon. 

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I started out using raci diagonals and I really disliked mirror diagonals and their confusing views but as time went by I got a mirror and gotnused to the improved quaoity of the view and gradually I used that more. Nowadays I don't often use a raci diagonal but I still have one just in case.

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 I use the Baader/Zeiss BBHS or Takahashi prism's in my refractors, giving a north top east/west reversed image. As most maps of the Moon are printed with either the standard wrong way up right way round reflector view, or right way up wrong way round refractor with standard diagonal view, it's easy to locate features. 

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20 hours ago, Highburymark said:


Nice choices Steve.

I tend to use the amici when I’m panning around the surface, and looking at features on a wider scale. I use binoviewer and Nagler 13s for an expansive view, and I do prefer a left-right orientation for this. Think it’s because I studied lunar maps from a young age and still find it more natural. Then for close up lunar details I more often use a right-left prism or mirror. It just involves a little thought before I set up.
To be honest, everything looks so great on the Moon - including pretty much every eyepiece, telescope and diagonal I’ve ever used - that it’s not the best target for distinguishing critical performance differences. So for those who prefer correct orientation on the Moon, a quality amici is well worth considering. 

Yep, bino and 13 Naglers for me also Mark , on Lunar and planetry, the perfect combination in my scopes.

Edited by Saganite
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On 03/04/2024 at 10:06, Highburymark said:

Baader T2 amici prism diagonal is as good - or better - quality than most diagonals out there and shows a non-reversed image. On a bright star at high magnifications you can just perceive a tiny spike if you look for it, but it’s a non-issue. So for those who prefer a ‘normal’ view of the Moon, yet don’t want to compromise the view, the Baader comes highly recommended. 

I've recently bought the Baader T2 Amici Astro quality prism.  - They do some cheaper ones, but only two 'astro" quality, the other being a non-T2 version with a 2inch clicklock eyepiece fitting and 2 inch nosepiece.

So far I'm very pleased with it.  The main reason I  bought it is I have never liked the mirror image of standard prisms/diagonals as it is a 'false' view which does not exist in reality.  This applies to every object of course, not just the Moon.  I intend to write a review when I've had more star time with the amici-prism.

 

Edited by paulastro
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6 hours ago, paulastro said:

I've recently bought the Baader T2 Amici Astro quality prism.  - They do some cheaper ones, but only two 'astro" quality, the other being a non-T2 version with a 2inch clicklock eyepiece fitting and 2 inch nosepiece.

So far I'm very pleased with it.  The main reason I  bought it is I have never liked the mirror image of standard prisms/diagonals as it is a 'false' view which does not exist in reality.  This applies to every object of course, not just the Moon.  I intend to write a review when I've had more star time with the amici-prism.

 

Excellent Paul - do report back. 

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6 hours ago, paulastro said:

.... The main reason I  bought it is I have never liked the mirror image of standard prisms/diagonals as it is a 'false' view which does not exist in reality.  This applies to every object of course, not just the Moon.....  

 

I think our brains flip the image that our eye projects onto the retina. Who is to say what is "reality" ?  🙂

Hope you enjoy your new diagonal 🙂

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Just remember, in the southern hemisphere the moon is also upside down.

Whether or not something is the right way round depends on where you happen to be at the time :wink2: It's all relative.

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The funny thing about mirror diagonals is the objective lense in the scope rotates the image 180 degrees so it's upside down and left is right, and then the mirror flips that upside down but does not change left/right. So in final state that is presented, up is up and left/right is reversed. So it is the objective not the diagonal that is doing the left/right reversing.

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2 hours ago, Mr Spock said:

Just remember, in the southern hemisphere the moon is also upside down.

Whether or not something is the right way round depends on where you happen to be at the time :wink2: It's all relative.

I don't mind an upside - down Moon, its a 'real' image that you could see if you travel there just by turning your head.  You won't see a mirror image!  (apart from when shaving 🙂)

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4 hours ago, paulastro said:

I still prefer to see the same image orientation through a telescope as I see with my eye alone - others can make their own choice 😂.

 

How do you achieve that with a newtonian ?

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10 hours ago, John said:

How do you achieve that with a newtonian ?

I don't think I've been very clear., sorry.  If you want to you can just turn you're head, but there's no need to. My point  is that an inverted view is 'real' in the sense  it is a view you can see on the Moon - as others have pointed out, there is no upside down in space.  On the other hand you will never see a mirror image view of the Moon unless you are actually looking in  a mirror - or using an ordinary diagonal prism or mirror diagonal on your telescope.

If someone carved some writing in huge letters on  one of the mare and you looked at it from the earth in a telescope with a mirror image diagonal - what you would see is not a view you can see if you just went there and looked with your unaided eye.  The reversed writing you see in the diagonal is not 'real'.

The funny thing is,  if diagonals had not been invented yet, and people wanted something to make it easier to look through a telescope pointing high in the sky so as not to crick their necks - they would probably reject a device which gave a mirror image as unacceptable.

Anyway, if no-one else is bothered and people want to be looking at  a 'false'  image, that's fine by me - give me a good amici -prism any time 😂.

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It’s funny, every day when I look at my handsome visage in the mirror, I don’t think it looks false 🤪

I’d rather see maximum detail personally but if slightly less but the right way round suits you, that’s fine of course.

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