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Tell us about your astronomy glasses


Paz

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I recently had my eye check up and had to get new glasses as my astigmatism has rolled around a bit.

I got a special pair just for astronomy for the first time. I added 0.25 dioptres for better focus in the dark at infinity. This works but I think if I had gone for adding 0.5 it would have been even better.

I got a pair with bigger lenses so I could fit wide angle afovs into my glasses field of view. They don't suit me style wise (I look like I'm an extra from a dodgy 1970s movie) but they do cover the field of view of my wide angle eyepieces.

I went for thinner glass to save weight but this turns out to be a mistake as they dew up quickly in the field if I take them off. Odd as it may seem I think I should have gone with fatter lenses.

I also picked a pair with the lenses that are more square to the eyepiece. I notice many glasses are tilted down to some degree which I guess isn't ideal at the end of an optical train where everything else is square.

I looked for glasses that sat closer to my eyes to get better eye relief and I have managed to gain a few mm in this respect.

I went for the non reflection coatings but I do this anyway so it was not a "gain".

Overall they are an improvement but next time I'll change a few things having learned from this time.

In the pictures below my old glasses are on the left and my new ones on the right.

I'd be interested to hear about other people's glasses where they have been specified in some way to help with astronomy.

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Hi there,

I also have astigmatism but find that it is easier to view deep sky objects without spectacles - gives a larger field of view with more contrast. Unfortunately this means that I am constantly having to put them back on to consult star charts.  My solution was to remove one of the lenses from an old pair of glasses and cut away the lower part of the corresponding frame  - I can read with the spectacled eye and view through the EP with the unspectacled one.

John

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Your left eyeglasses look about identical to my daily wear pair.  I went with a larger, squarer frame for astronomy rather than rounded.  They still cut off the top and bottom of the field in my ES-92s, but are fine left to right.

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5 hours ago, westmarch said:

Hi there,

I also have astigmatism but find that it is easier to view deep sky objects without spectacles - gives a larger field of view with more contrast.

It certainly works better to take off my glasses with short eye relief eyepieces, but unless I'm down below 1mm exit pupil, stars are spiky and planets lose some detail.  2.0 diopters of astigmatism make stars super spiky at 2mm and higher exit pupils.  Dim stars also just disappear altogether kind of ruining the experience.  What's the point of using expensive eyepieces if the image is terrible looking?  I'd have to wear contacts to use Ethos eyepieces, but I already have enough issues with scratchy, dry eyes.

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Good topic, I don’t have a pair but often thought of contact lenses that can correct for astigmatism, this would be great as you wouldn’t have to specifically look for eyepieces with long eye relief. That is of such a thing is possible.

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11 hours ago, Paz said:

I added 0.25 dioptres for better focus in the dark at infinity. This works but I think if I had gone for adding 0.5 it would have been even better.

I did the same thing, many years ago. On advice from the optician I bought a second pair with ½ dioptre more correction - just plain lenses: no varifocal or photochromic finishes.
Be aware that at night when your pupils are fully dilated, focus becomes more critical. Just like with short focal length telescopes. So it is more important that your prescription is accurate. I presume that is why eye tests are carried out in a low-light room.

Of course, for astrophotography it doesn't matter. ;)

Edited by pete_l
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5 hours ago, Louis D said:

Your left eyeglasses look about identical to my daily wear pair.  I went with a larger, squarer frame for astronomy rather than rounded.  They still cut off the top and bottom of the field in my ES-92s, but are fine left to right.

My old pair were ok left to right but would cut off the top of the view through Naglers and Delos.

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I have Astronomy only glasses for Astigmatism at the Eyepiece and so I can also pick out stars to point my finder / telrad /rigel at as well.
Yes single lens, no readers in, even though I need them, but thye get in the EP view.
No coatings as advised by my optician, they scratch she told me, had to laugh as its anti scratch coating.
The lenses and style like @Paz are not my fashion (ahem) choice, but have a bigger rounder EP lens covering size.

My dioptre is 0.75 and the lens is set a 1.00, i wish I had tried 1.25 as some slight astigmatism shows, oddly in middle range FL eyepieces,
not at the largest exit pupils, but nearer the cusp of it not supposedly showing.

So thanks to this thread, I may get a differing set of lenses made up and fitted.

 

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6 hours ago, Alan White said:

No coatings as advised by my optician, they scratch she told me, had to laugh as its anti scratch coating.

I don't like how coatings peel away at the edges of lenses over the years.  It looks terrible and can't be good optically.

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17 hours ago, Paz said:

I went for thinner glass to save weight but this turns out to be a mistake as they dew up quickly in the field if I take them off. Odd as it may seem I think I should have gone with fatter lenses.

Not only that, but higher index lenses have more dispersion, so stars at the edge of the field spread out into rainbows more obviously.  I get the cheapest base pair of lenses and live with the slight extra thickness.  This isn't an option for everyone.  My middle daughter has 5.0+ diopters of distance correction, so even high index lenses look thick.  She mostly wears contacts as a result.

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Sympathise on the lenses front.  I'm -8 (near sighted) in both eyes.  In real terms it means I can't focus on anything further than 4" from my eyeball.  My lenses are quite chunky.

I used to get the optician to put polycarbonate (safety glass) lenses in the frames.  They're as thin as the thinnest real glass, but can't take a coating.  The main benefit though, they cost the same as bog standard lenses.  Meant I could wear fancy frames.

Now I don't care about the look and just order Joe 90 frames.

 

 

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An interesting thread. Very good thinking by the OP.
Some things to remember if I have to consider specs for scope use.

My solution has for some years been contact lenses.
Immediate focus on infinity with astig corrected.
They don't dew up.
They are in line with the optical train.
They give a free choice on EP eye relief (subject to neanderthal brow ridges of course🤣)
If I need a near vision or small parts view for charts, displays and little fiddly things, then cheap off the peg reading specs do the job.

Don't forget that near/far sight correction (within reason) is not necessary as racking the focus in/out will sort this.
Certainly 3D is easily done, in my experience.

Spare a thought for the poor chap an optician told me he encountered while in training.
This fellow need 33 dioptre correction. Achieved by a combination of (from memory) 20 in the specs and 13 in a contact lens.
All well and good until he went for a check that required him to not wear his contact lenses for some hours before.
He cycled to the hospital with 13D of correction omitted!

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55 minutes ago, Carbon Brush said:

An interesting thread. Very good thinking by the OP.
Some things to remember if I have to consider specs for scope use.

My solution has for some years been contact lenses.
Immediate focus on infinity with astig corrected.
They don't dew up.
They are in line with the optical train.
They give a free choice on EP eye relief (subject to neanderthal brow ridges of course🤣)
If I need a near vision or small parts view for charts, displays and little fiddly things, then cheap off the peg reading specs do the job.

Don't forget that near/far sight correction (within reason) is not necessary as racking the focus in/out will sort this.
Certainly 3D is easily done, in my experience.

Spare a thought for the poor chap an optician told me he encountered while in training.
This fellow need 33 dioptre correction. Achieved by a combination of (from memory) 20 in the specs and 13 in a contact lens.
All well and good until he went for a check that required him to not wear his contact lenses for some hours before.
He cycled to the hospital with 13D of correction omitted!

That's mental.  Would have cost a bloody fortune.

 

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1 hour ago, Carbon Brush said:

This fellow need 33 dioptre correction. Achieved by a combination of (from memory) 20 in the specs and 13 in a contact lens.

If nearsighted, does his eye focus behind his cornea? :icon_scratch:

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My observing glasses:

https://www.glassesusa.com/gold-medium/ray-ban-6392-ja-jo/44-000164.html

The frame is outside visibility no matter how large the eyelens is.  They work on Morpheus, Delos, ES 92, etc and no frame is visible in the FOV.

I corrected for infinity vision.  I have another pair for reading at my charts and for writing notes when I move to my table to do so.

My vision is good enough to read the DSC at night, even if it is not sharply in focus.

I went for lenses to reduce CA and the best anti-reflection coatings.

I only use them observing.  I call them my "John Lennon" glasses.

See: https://www.onthisday.com/people/john-lennon

 

Louis' comment about coatings peeling away after years made me laugh.  I have my eyes checked yearly, and my prescription has only been the same two years in a row once since age 40.

I usually get 3-5 new pairs of glasses a year (computer, driving, daily life, transitions, astronomy).  I can afford it, plus I notice the difference at the telescope.

Edited by Don Pensack
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13 hours ago, Don Pensack said:

The frame is outside visibility not matter how large the eyelens is.

My bushy eyebrows get in the way of anything poking up that high.  I've got Neanderthal brow ridges pushing them out even further.

13 hours ago, Don Pensack said:

Louis' comment about coatings peeling away after years made me laugh.  I have my eyes checked yearly, and my prescription has only been the same two years in a row once since age 40.

Bummer.  My prescription changed yearly for about 4 years in my mid-40s when presbyopia set in.  Then, it settled down and I haven't had a major shift in a decade since.  That's not to say it won't shift again someday.  I'm currently wearing 8 year old bifocal glasses because a nose pad came off my 7 month old pair of daily wearers.  I'm heading out to my eyecare place today to get it replaced.  The prescription is basically the same between the two, and I adjusted in minutes.  There's always fudging of that last quarter of a diopter as far as which one works better, especially when the phoropter goes down to an eight diopter, so you have to go either up or down an eighth for lenses if you land between them for best correction.

13 hours ago, Don Pensack said:

I usually get 3-5 new pairs of glasses a year (computer, driving, daily life, transitions, astronomy).  I can afford it, plus I notice the difference at the telescope.

I generally get one new pair of bifocals a year because they're completely paid for via work insurance.  This last time, I got a pair with magnetic clip-on polarizing sunglasses.  That way, I get polarized bifocals for cheap.  My insurance won't cover polarizing lenses or tints, but they will cover clip-ons.  I buy my reader, computer and astronomy single vision glasses from EyeBuyDirect for a tiny fraction of what my eyecare place wants.  The brick and mortar store has got massive overhead to cover (building, labor, etc.), but I figure I do my part getting a yearly eye exam and pair of glasses to support them.

In fact, I am wearing computer glasses I bought 5 years ago as I type this.  Absolutely no reason to replace them that I can find.

14 hours ago, Don Pensack said:

I call them my "John Lennon" glasses.

If I could get oblong frames to custom fit within my eye sockets like two monocles, that would be ideal for eye relief and full coverage.  Instead, pretty much all frames sit fully in front of your eye socket which is an eye relief and coverage killer for Neanderthals like me.  Yes, I could go with contacts, but I've read that toric lenses tend to spin while hunched over an eyepiece, ruining astigmatism alignment.  That, and I'm outside exposed to year-round eye irritants here in Texas.  There is no off season for pollens here.

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Like others above my prescription changes yearly, especially the astigmatism angle.  In fact the latter changes during the course of the year.

For that and many other reasons I don't wear glasses at the telescope but correct my astigmatism with a Televue Dioptrx.  With this I can correct the angle at the scope.

It's often suggested that astigmatism gets somewhat worse in low light.  I therefore tested this by comparing a 0.75 dioptre Dioptrx as per my prescription against a 1.00 Dioptrx.  The latter was indeed better.

It's not just astigmatism that usually needs a higher correction in low light.  Especially if you're short-sighted you'll probably need greater spherical correction as well.  This is called "night myopia".

My helpful opticians, Neil Gordon and Co in London, lent me flipper lenses to hold in front of my glasses.  I found I needed an extra 0.625 dioptres correction in my left eye and an extra 0.5 dioptres in the right eye at night.  I therefore had them make up a special such pair for naked eye astronomy, including an extra 0.25 dioptres astigmatism correction in both eyes.

 

Edited by Second Time Around
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I have double-vision so I must wear specs. A major problem with specs is fogging when using my binoviewer and binoculars.

The solution to fogging was to take the plastic lenses from a spare pair of specs and reduce them in size, by sawing and filing, to fit into the eye cups of the binoviewers and bins.

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1 hour ago, Second Time Around said:

Like others above my prescription changes yearly, especially the astigmatism angle.  In fact the latter changes during the course of the year.

That's really rough.  I'm hoping my eyes never start doing that.  My astigmatism amount and angle have remained relatively constant after presbyopia set in and stabilized a decade ago.

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On 28/04/2022 at 08:35, Louis D said:

I don't like how coatings peel away at the edges of lenses over the years.  It looks terrible and can't be good optically.

I've found the coatings on my mine yellow over time.  Don't know if that's because I clean them with liquid dish soap or they maybe react to UV or air contaminants.

With my progressive prescription, etc., my glasses are close to $800 US per pair, so I don't buy extra pairs specifically for astro.  I guess I could try a cheap pair of single vision sometime.

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1 hour ago, jjohnson3803 said:

I've found the coatings on my mine yellow over time.  Don't know if that's because I clean them with liquid dish soap or they maybe react to UV or air contaminants.

With my progressive prescription, etc., my glasses are close to $800 US per pair, so I don't buy extra pairs specifically for astro.  I guess I could try a cheap pair of single vision sometime.

Absolutely go with single vision in the base plastic lens.  That way, the entire field is in focus at once, you can look up to the sky as needed, dispersion is at a minimum off axis, and cost is low enough that you don't feel bad about having a dedicated pair for astronomy.  Check online retailers.  I've bought a pair of Brodie frames for $9 and a pair of Bennet frames for $19 from EyeBuyDirect and have been perfectly satisfied with their quality.  To avoid coatings on the lenses, on the lens selection page go into clear->customize->1.5 index lens included and there's no additional charge for the lens.  Imagine paying under $20 for a pair of quality single vision eyeglasses.  I took a leap of faith, and haven't been disappointed.  I've got readers and computer glasses from them as well.  Just ask your optometrist for the appropriate prescription for each usage.

I don't know if they sell worldwide, but I would hope there are similar online retailers in other parts of the world.

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Not wishing to stray too far off this interesting topic, but would folk recommend 'overcooking' the spec for a TV Dioptrx by 0.25 or so, similarly to astro glasses?  (I've been thinking one could be my next purchase! 🙄)

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29 minutes ago, niallk said:

Not wishing to stray too far off this interesting topic, but would folk recommend 'overcooking' the spec for a TV Dioptrx by 0.25 or so, similarly to astro glasses?  (I've been thinking one could be my next purchase! 🙄)

Yes, almost certainly.  My astigmatism prescription in my observing eye is 0.75 dioptres.  I compared both 0.75 and 1.0.  The latter was better.

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