Contact lenses, glasses or nothing for viewing?

[johngwheeler (John)]

Hi,

I'm quite myopic (-4.25d) and normally wear contact lenses. I believe I have slight astigmatism, but have never really noticed this manifest itself when wearing glasses or contact lenses.

I do find that I have to blink quite a bit to remove "flare" or "coma" effects (not sure if my terminology is correct!) from very bright objects (e.g. Moon, Venus, bright stars). Is this normal, or an effect of my contact lenses?

Would I be better off wearing my glasses? Downside is eye relief, extra layer of glass reducing brightness, and additional imperfections in my glasses.

If I remove my lenses and glasses, would I then have problems with astigmatism, which are at least corrected somewhat by the lenses / glasses?

Just interested to hear what experienced short-sighted astronomers do!

[glend (Glen)]

Well I generally find that I am taking my glasses off and putting them on alot when observing. Contacts are not an option as I have a multifocal script and need my glasses to read as well as distance. The good thing about a telescope is that you can adjust the focus to suit your eyes, not so good if your sharing it with others (who need to re-adjust). I have found that imaging is less of an issue because I am not looking through the EP much at all as everything is done through the camera and laptop. Perhaps this is one factor that encourages people into imaging. Re astigmatism, it is usually unequal, meaning that you will have one eye that is much better in this regard than the other. An eye test will tell you this. Simply use the eye least affected and you should be ok.

[Renato1 (Renato)]

I have bad astigmatism, and it shows up worst at low power at 3 to 6 mm exit pupils. But at 0.5mm to 2mm exit pupils, it's not really noticeable.

One usually has longer eye relief at low power (unless it's an ultra-wide angle eyepiece), and one can wear glasses to get rid of the astigmatism. Or when you get a new set of lenses from a new scrip, get the optometerist to cut/grind your old lenses into circles, cutting a little mark at the top of the lenses to show where up is. Then you can attach the lens to an eyepiece with Blutack.

With really big exit pupils like at 8 or 9mm (i.e. very low power), I don't need glasses - instead I just tilt my eye and get rid of the astigmatism, without part of the image blanking out, as woudl be the case with smaller exit pupils.
Regards,
Renato

[BilliGoatsGruff (Billi)]

I normally take my glasses off when using my telescope. I need them for distance, so sometimes it can be a pain, but I'd much rather take them off when looking through an eyepiece, rather than have the discomfort of my glasses pushing on my nose you may have to adjust the focus a bit to accommodate the change, but I haven't had any issues that would make me think you have to wear your glasses. I'm not sure about contacts though, I'm not brave enough to try them! of course, this is just my opinion. Every person is different

[OzStarGazer]

Originally Posted by BilliGoatsGruff

I normally take my glasses off when using my telescope. I need them for distance, so sometimes it can be a pain, but I'd much rather take them off when looking through an eyepiece, rather than have the discomfort of my glasses pushing on my nose you may have to adjust the focus a bit to accommodate the change, but I haven't had any issues that would make me think you have to wear your glasses. I'm not sure about contacts though, I'm not brave enough to try them! of course, this is just my opinion. Every person is different

Yes, I take them off too and just adjust the focus. I find it terribly uncomfortable to use them while looking through an eyepiece, although apparently it depends on the ER, so with good eyepieces it should be OK to wear glasses, but I still prefer not to wear them (even when using my good eyepieces!).
But as you said we are all different and we must all choose what is best for us.
PS: I can't wear contact lenses because I suffer from insomnia and then I rub my eyes a lot during the day because they are itchy...

[BilliGoatsGruff (Billi)]

Originally Posted by OzStarGazer

Yes, I take them off too and just adjust the focus. I find it terribly uncomfortable to use them while looking through an eyepiece, although apparently it depends on the ER, so with good eyepieces it should be OK to wear glasses, but I still prefer not to wear them (even when using my good eyepieces!).
But as you said we are all different and we must all choose what is best for us.
PS: I can't wear contact lenses because I suffer from insomnia and then I rub my eyes a lot during the day because they are itchy...

*sorry to hijack your post john*

I spent my whole childhood and teen years being told that I need multifocal lenses for reading and long distance. I changed my optometrist 2 years ago (from OPSM to SpecSavers) and found out that I only need single vision lenses! I'm that used to wearing glasses now though that the idea of using contacts gives me the heebie jeebies.

[OzStarGazer]

I am sorry to hijack your thread too, John...

... Well, eye doctors are not always right... The last time I went my doc said that something strange happened with my eyes as my weak eye is now the strong one. No... My right eye has ALWAYS been my weak eye. I think he just messed up left and right when I went a couple of years ago. I like him because he is a nice doc, so I didn't say anything, but I know my eyes.

[RB (Andrew)]

I'm so glad I had laser surgery done on both eyes.
Never looked back, pardon the pun.

[BilliGoatsGruff (Billi)]

Originally Posted by OzStarGazer

I am sorry to hijack your thread too, John...

... Well, eye doctors are not always right... The last time I went my doc said that something strange happened with my eyes as my weak eye is now the strong one. No... My right eye has ALWAYS been my weak eye. I think he just messed up left and right when I went a couple of years ago. I like him because he is a nice doc, so I didn't say anything, but I know my eyes.

Haha yes, that is a doozy. He must have partied too hard the night before

[Chif (Andrew)]

I tend to wear my contact lenses. I'm near sighted so you might think that it'd be an issue, but I certainly prefer it. Makes it easier if others are viewing as well.

[dannat (Daniel)]

i used to wear my contacts but found removing them after a long nigt [sometimes in the dk] to be a pan, i tend to use glasses for naked eye & take them off at the telescope -i try to leave them on when looking thru a finder

[inertia8 (Australia)]

Each to their own, I got a bit annoyed at having to put them back on each time I needed to look up to aim the scope!

I've ended up buying long eye relief eyepieces and find a plus is that wearing glasses prevents eyelashes from being able to contact the lens!

[Rick Parrott]

I have been finding of recent that my glasses are good for most viewing, unless I'm using higher magnification (i.e. 6mm,10mm eyepieces). Looking forward to my first Tele Vue 8mm Plossl arriving later this week which should address some of the poor eye relief I find on high-power usually.
Using my glasses also means that the focus is much closer for others when they have a peek

[scoperboy (Stuart)]

+1 for wearing glasses naked eye and then taking off for scope views.

Having said that I leave glasses on for naked eye and finder scope, but I always take glasses off at the eyepiece. It is a bit of a pain.

[Wavytone]

+1 glasses, I use Vixen LVW's which have lots of eye relief - enough to wear glasses when looking through the eyepiece for a quick look. For a longer look I'll take the specs off.

The other thing is these have a rubber eyecup to stop them being scratched - a lot of other eyepieces have nasty sharp edges that will ruin expensive specs.

[doug mc]

Something else to consider. Bino viewing. Fortunately our brain has a way of merging the views and presenting the best view as a compilation. I an over 60 and have eye floaters and astigmatism. Bad combination. But with a binoviewer I get the best views posible with such eye conditions. I would suggest long eye relief eyepieces anyway. That way you can try it both ways.

[astroron (Ron)]

I will give up astronomy if I cannot wear contact lenses anymore.
Glasses to me are a big pain at the eyepiece.
I have reading glasses to read the ARGO NAVIS and charts etc
I had a period when I couldn't wear my contacts,and the changing of glasses from normal sight to reading and back again drove me up the wall.
The new multi focal glasses I have for when I am not using my contacts made me unsteady at the eyepiece.
No contact lenses equates to no observing,period
Watch this space in the future for an astro goodies sale.
Cheers

[rrussell1962]

+1 for contacts. I am myopic and have fairly severe astigmatism in both eyes which is corrected with toric lenses. Drying out in the night air can be a problem so I keep a bottle of blink and clean in my pocket. The prescription for each eye is so different that the optometrist suggested having one lens corrected for longer vision and one for reading. It took about a week to get used to but now I automatically switch eyes. Vision tested at 20 / 20 at my last eye test a few weeks ago. Having said that I do find reading glasses useful for charts etc while observing, possibly to compensate for the dim light.

[ausastronomer (John Bambury)]

Hi John,

I am short sighted about -2.00 with .75 astigmatism. Over the past 40 years I have tried just about every combination of eyepieces, glasses and contact lenses known to man. I have found that the best option for me is to use high quality multifocals combined with long eye relief eyepieces which enable me to leave my glasses on all the time.

The advantages to me of doing this are many:-

1) I Don't need to change anything when I look up at the sky for naked eye views
2) I Don't need to change anything when I look through a TELRAD or finderscope
3) I Don't need to change anything when I read star charts, or the Argo Navis
4) I Don't need to change anything when I change eyepieces
5) I Don't need to change anything when I use my binoculars, both pairs of which also have long eye relief and can be used with glasses on.
6) I can actually see the people I am observing with and talking to on the observing field.
7) When I do outreach and share the views with others, which is very often, I advise all glasses wearers to leave their glasses on which greatly reduces the amount of refocusing required and makes it much easier for the subsequent observers to find focus.
8) When using large telescopes like 25"/F5 and 30"/F4.6 SDM's and Obsessions, which can have you 10 feet in the air on a ladder, I like to keep one hand on the ladder for stability and the other hand on the telescope / focuser. I don't need to find an extra arm to take my glasses off and still hang on when I get up the ladder.

A couple of important riders. You need to use decent quality eyepieces (within your budget) that have 20mm of eye relief (or very close to it) and most importantly that have a rubber eye guard which prevents you scratching a) The lenses of your glasses and b) the eye lens of the eyepiece. People will tell you they can use their X, Y, or Z focal length ETHOS which barely has 13mm of eye relief with their glasses on, but IMO this is just asking for trouble and something will end up scratched. Been there done that ($1,000 pair of Zeiss glasses lenses in the garbage bin). Some good options include Pentax XW's, Pentax XL's, several of the Vixen series including LVW's and LV's etc, TV DELOS, Nagler T4's, 31mm Nagler T5, 27mm, 35mm and 41mm TV Panoptics, Baader Hyperions and Orion Stratus etc. Their are quite a few others as well, including some cheaper Asian imports which are fine to use with glasses on. Some are fairly expensive some are fairly cheap. You usually get what you pay for.

I use multi focals but I don't use cheap ones. The more you pay for them the higher the refractive index of the plastic in the lenses, which, gives a much thinner lens, with much better optical properties than the cheaper thicker lenses. Most importantly the higher refractive index lenses are much thinner at the edges and give a much larger distortion free field of view. As your prescription strength increases high refractive index lenses becomes more important. They are also a lot lighter. Unfortunately the top quality lenses aren't cheap. A set of 1.67RI or higher multifocal lenses from a reputable maker like Hoya, Zeiss, Rodenstock etc. with all the AR and anti scratch coatings and the like will cost well west of $500, without frames.

http://www.allaboutvision.com/lenses/highindx.htm

The important thing to remember is that this is a very subjective thing and the above is what I have found works best for "ME" based on my observing situation and preferences. Depending on your observing situation and observing preferences there may be other options which suit your situation and preferences better.

Cheers,
John B

[ausastronomer (John Bambury)]

Originally Posted by rrussell1962

+1 for contacts. I am myopic and have fairly severe astigmatism in both eyes which is corrected with toric lenses. Drying out in the night air can be a problem so I keep a bottle of blink and clean in my pocket. The prescription for each eye is so different that the optometrist suggested having one lens corrected for longer vision and one for reading. It took about a week to get used to but now I automatically switch eyes. Vision tested at 20 / 20 at my last eye test a few weeks ago. Having said that I do find reading glasses useful for charts etc while observing, possibly to compensate for the dim light.

Hi Russell,

I have tried contact lenses for observing on and off over many years and never had much joy. Two reasons it didn't really work for me was the drying out of the eyes, as you mention. Most importantly however was the fact that the lenses I used obtained the astigmatism correction and orientation by weighting the lens at the bottom to maintain their orientation due to gravity. Unfortunately, I found that every time I turned, tilted or rotated my head to accommodate the orientation of the eyepiece, finder scope or telrad the contact lens would maintain its orientation due to gravity. This meant its orientation was incorrect for proper astigmatism correction due to the changed orientation of my head. This actually made me feel quite disorientated and nauseous.

They obviously work well for some though, that's why I tried them several times, before dissing them. Unfortunately, I ended up in the same paddock every time.

Cheers,
John B