Eyesight and astronomy

[spaceboy]

I have my yearly eye test booked for tomorrow and some recent conversations got me a thinking. As astronomers we seem to be a critical bunch when it comes to night sky views. Coma, spherical & chromatic aberrations being amongst the most obvious reasons why we critique the views and spend a fortune on top end scopes and eyepieces, but just how many of us consider the MK 1 eyeball itself as being the culprit of poor performance ? Thanks to my fathers gene pool I am at high risk of glaucoma so eye tests are a regular occurrence for me which, while I hate the intraocular pressure test, it suits me to know my eyes, other than some annoying floaters, are performing at their best or at least as near to 20-20 as I can hope for given my age and hours spent staring at the SGL website

When you consider the list of eye diseases and disorders http://www.bausch.com/your-eye-concerns/diseases-and-disorders along with the usual near and far sightedness that we often attend the optician for, there are quite a few things that can influence our enjoyment of the night sky that might other wise be overlooked in normal day to day life. Many people also don't realize that smoking can lead to vision loss. Studies show smoking increases the risk of age-related macular degeneration, cataracts, glaucoma and diabetic retinopathy and Dry Eye Syndrome. It is easy enough to blame your kit for not offering up the best views but when you think about it, how easy is it to overlook the MK 1 eyeball as to being at fault ? I understand how it can be overlooked as how often during your daily activities do you challenge your eye to squint through a 2-12mm hole at tiny points of light? and when the time comes that we do, it is in total darkness when our eyes don't perform at their best anyway.

I know astigmatism has been mentioned by some members as effecting their night sky views and I believe Televue actually offer a lens screws to their eyepieces to help sufferers which would suggest it is more common than some may think. How would someone know the astigmatism they see in an eyepiece is eyepiece related or due to their own eyes? Is it something that effects people in day to day life or is it only something experienced at the eyepiece ?? Have any other members ever found they were regularly having poor views despite swapping out eyepieces or scopes only to find their own eyesight was the culprit ? 

It may seem a little extreme to consider it, but I am interested to hear what my optician has to say tomorrow as just lately I have really struggled to have a good nights observing. Washed out views and generally poor seeing has been to blame but this has been going on for time now. I'm pretty sure my scopes are up to scratch and a recent change in eyepieces has seen no noticeable difference. If my eyes are indeed still all good I am going to have to start thinking seriously about going further afield to do my stargazing

[ronin]

Taken into account very little.

You know the talk of the scope and eyepiece creating an magnified image? Well the optics is that the scope and eyepiece do not form an image, it is collimated light in and collimated light out, no image.

I often make the comment that with my eyes then the BST Starguiders are likely going to do everything I want or need, might get something a bit better but I suspect it will be a case of a fair jump in outlay for a small difference. Reason being I know these 2 little eyeballs I have fairly well. Mind you I am not sure that the oticians I visited a few months had any idea.

[laser_jock99]

Get a camera.......

[Charic]

 

41 minutes ago, spaceboy said:

I have really struggled to have a good nights observing. Washed out views and generally poor seeing has been to blame but this has been going on for time now. I'm pretty sure my scopes are up to scratch and a recent change in eyepieces have seen no noticeable difference.

My scope and eyepieces are a perfect match for the task in question......  lol.  So I can only blame the weather and seeing conditions.
Although I no longer have 20/20 vision, my focuser corrects for my myopia, but I do wear and require prescription glasses for driving.
 I too have tried some exotic premium eyepieces, like the Delos (without Dioptrx) and found no magical or any  performance  gain except the field of view, over my present eyepieces, BST Starguiders.

I doubt your scope and setup is much different to my situation, we think what we've  got is perfect? So gotta blame something else?
Come back and surprise us, but there probably won't have been much change in your eyesight since your last examination, lets hope not. 

[Pondus]

50 minutes ago, spaceboy said:

How would someone know the astigmatism they see in an eyepiece is eyepiece related or due to their own eyes?

If the  stars elongated axis changes its angle when moving your head around the eyepiece, I think it might be your eyes..

 

[scarp15]

I don't really think about it too much, what I have become aware of is that progressively gaining and developing in experience with visual astronomy, I feel that I have learnt and continue to learn to see many and varied objects with a degree of clarity and comprehension. This actually applies whether at a dark site or within my local sky and taking account for the conditions. Yet I have just turned 55, I do wear reading glasses which are highly necessary now for studying charts. What I would find interesting is to compare a target with a younger observer. My nephew is always interested whenever I pay a visit to Lancashire, My 16 yr old daughter sadly not really. I can tease colour out of Jupiter and M42 so really am quite happy. I do share with you the glaucoma issue and necessity for a yearly check up, apparent in both sides of family and agree that smoking really has nothing going for it.

[Paz]

I didn't know I had astigmatism until I had my first scope and thought it had a problem, only to eventually work out it was my eyes. I now prefer observing with glasses hence going for long eye relief eyepieces like SLVs and Delos.

I also first discovered what floaters are when looking at the moon with small exit pupils.

As well as your eyes there is your brain... I notice sometimes I can't split a double one day and the next I can but not always  because of seeing. I think sometimes I'm just better able to really concentrate.

 

[niallk]

I diagnosed myself with a little astigmatism with my scope - I was getting my eyes tested for contacts and I asked the optician did my right eye show a little: she was surprised but when I explained that I use a telescope, she was very helpful: showing me what my prescription would be like with / without the astigmatism correction part present. She also priced contacts with astigmatism correction built in for me. I'm 0.5 dioptre in my right eye, and the difference the correction made when viewing an array of black dots on a white background was quite dramatic.  Makes me want to try Televue dioptrix sometime!

[Charic]

2 hours ago, niallk said:

Makes me want to try Televue dioptrix sometime!

Another reason to future proof my observing, but alas did not give myself the time or chance to obtain a Dioptrx eyepiece for the Delos EP's  I previously owned!
Maybe if I had a faster scope, the outcome of my TV foray may have been quite different, but  I soon realised I don't need the Delois for my f/6 Skyliner, and with some other serious expensive  projects on the go at present, no regrets, just yet.

[oobydooby]

Following a stroke 20 odd years ago in which the right side of my brain was damaged I have homonymous hemianopia.  Wkipedia has an excellent description of this but the upshot is I am blind on the left side of each eye.  The picture demonstrates roughly what I can see, so imagine what looking through a trelescope is like.  For me the widest angle rather than the magnification is most important, and as I cannot drive, weight is also a big deal, so I might have the desire for better and bigger etc., but in practical terms binos and smaller, lighter gear have to be my main crieria.

[spaceboy]

3 hours ago, oobydooby said:

Following a stroke 20 odd years ago in which the right side of my brain was damaged I have homonymous hemianopia.  Wkipedia has an excellent description of this but the upshot is I am blind on the left side of each eye.  The picture demonstrates roughly what I can see, so imagine what looking through a trelescope is like.  For me the widest angle rather than the magnification is most important, and as I cannot drive, weight is also a big deal, so I might have the desire for better and bigger etc., but in practical terms binos and smaller, lighter gear have to be my main crieria.

That's a total bummer! Have you ever considered binoviewers as I bet they would help no end.

19 hours ago, Charic said:

I doubt your scope and setup is much different to my situation, we think what we've  got is perfect? So gotta blame something else?
Come back and surprise us, but there probably won't have been much change in your eyesight since your last examination, lets hope not. 

Well the eye test went as expected. There are no clouds or st lights in either of my eye balls  I may well require glasses in a couple years though so a slow transition over to LER eyepieces at some point is on the cards. 

I really do miss the views I was getting only a few years ago. It wasn't by any means perfect every night but I can't remember the last time I found something new in the sky at home as it's been so poor. I doubt the noticeable increase in air traffic over head hasn't helped and I'm sure they are flying lower every time I see them. I now know my eyes along with my scope and eyepieces are all good so with nothing else to blame, either a drive out to darker and hopefully cleaners skies or a camera is the way to go. Either that or I am just going to have to stick to the same old list trusty doubles, lunar, planetary and brighter DSO's.

 

When you consider a great deal of the hobby relies on your eyes to find and then observe night sky views, it has been interesting to read of peoples vision problems not stopping them from enjoying the hobby of astronomy though.

 

20 hours ago, scarp15 said:

What I would find interesting is to compare a target with a younger observer. My nephew is always interested whenever I pay a visit to Lancashire, My 16 yr old daughter sadly not really. I can tease colour out of Jupiter and M42 so really am quite happy. I do share with you the glaucoma issue and necessity for a yearly check up, apparent in both sides of family and agree that smoking really has nothing going for it.

I totally agree. I was a late starter to using a telescope in astronomy so I have never known truly what younger eyes are capable of. That said though my 7 year old son has a pair of photon eating black holes for pupils (they are insanely large and remind me of baby lemur in madagascar movie) yet I can't help but think while he can obviously pick out more in a distant galaxy than I can he cannot truly see the galaxy in the same light I can. The way an older mind can perceive and contemplate what it is seeing through the eye is the compensation for a smaller exit pupil. My 10 year old again can come along to star parties and gain the full advantage of a huge exit pupil but I ask what he sees and all I get is "a blob". I explain to him what it is and it registers but I can tell he doesn't understand the true depth of it.

[Stu]

I think this is a very valid point Nick, but not necessarily in the way that has been covered so far.

In my particular case, my two eyes are very different in their light sensitivity and the resolution of objects seen in low light. I do not know, but I think it is related to the retina or nerve pathways rather than the lens itself.

My left eye is my observing eye, and whilst it has some floaters, it gives very good planetary views which show levels of detail which I find satisfying at comfortable brightness levels.

My right eye seems to offer brighter images but which appear more like a poorly tuned TV, or at least more grainy than the left eye.

My point? Were both my eyes the same as my right eye I think I would long ago have given up planetary, lunar and possibly solar observing as the views would have been unsatisfying for me. Whether I would have blamed the kit or not I have no idea but to me it shows that eyes can be very different in ways that are harder to measure, or perhaps just are not measured in normal eye tests.

[Highburymark]

Excellent post.

I have fairly normal (for a 53 year old) myopia in my left (observing) eye, and astigmatism in my right. So have two pairs of glasses.

The only time I wear no specs is for stargazing. And frankly I can't work out how anyone can observe with glasses on. Clearly thousands of very proficient amateur astronomers do so every night - with the help of long eye relief eyepieces. So I must be doing something wrong. My vision is so clear through my glasses that I'd like to be able to use them for astronomy, but I can't establish anything resembling a satisfactory image. Must be poor technique, but thankfully my left eye is good enough to keep me involved in the hobby without the need for specs.

 

[Stub Mandrel]

I am quite short sighted, and well aware my prescription had changed I went for a test last week. I could have bought a new scope or a decent EP and a Ha filter for the cost of the glasses (OK the readers only cost £20... but I'll only use them for reading in bed, if at all).

What was interesting is that my left eye could be corrected to razor-sharp, but my right eye won't quite get there, good but not great. Both eyes together is will be brilliant when I have the new 'scrip.

Oddly the left has slight astigmatism, but the right hasn't got any.

Best news, over-pressure gone now my blood pressure is back to normal and no signs of glaucoma

But I wonder if the  sub-optimal right eye is one reason why I don't get one with eyepieces? I shall try observing with my left eye instead.

[spaceboy]

1 hour ago, Stu said:

I think this is a very valid point Nick, but not necessarily in the way that has been covered so far.

In my particular case, my two eyes are very different in their light sensitivity and the resolution of objects seen in low light. I do not know, but I think it is related to the retina or nerve pathways rather than the lens itself.

My left eye is my observing eye, and whilst it has some floaters, it gives very good planetary views which show levels of detail which I find satisfying at comfortable brightness levels.

My right eye seems to offer brighter images but which appear more like a poorly tuned TV, or at least more grainy than the left eye.

My point? Were both my eyes the same as my right eye I think I would long ago have given up planetary, lunar and possibly solar observing as the views would have been unsatisfying for me. Whether I would have blamed the kit or not I have no idea but to me it shows that eyes can be very different in ways that are harder to measure, or perhaps just are not measured in normal eye tests.

I was told today that I have very good eyesight for my age but as you say eyes can be very different in ways that are harder to measure, or perhaps just are not measured in normal eye tests. I can directly relate to this comment as I too found I get the best views when using my left eye for astronomy despite using my right for many a years hunting and target shooting with telescopic sights. Day light and comfortable eye relief seems to favour my right eye and at no point was a shot ever compromised because the target wasn't perfectly clear. Yet squint through a small ortho lens at balls of light and it all goes tips up. Thankfully the left eye does a far better job, that is when floaters aren't sitting directly inline with the GRS. I should try my right eye when observing white light to see if observing in the day helps any ????