Keeping Both Eyes Open

[hawklord2011]

Happy if you can point to an existing post but the one thing I've struggled with (on admittedly my first and only observing session) was looking through the eyepiece consistently. I was either too close and moving the scope or too far away and not seeing everything. Also I've read a lot about keeping both eyes open but had to keep closing one as I couldn't get my 'star eye' to dominate and ended up looking at my scope! Are there any good tips on keeping both eyes open and also on the best distance to be from the eyepiece?

[John]

I close my non-observing eye when looking into the eyepiece. It seems to have worked OK for me. I'm a left eye observer, as it happens.

The distance your eye needs to be from the top of the eyepiece often varies with the eyepiece focal length, for example with a 25mm eyepiece the right distance might be around 20mm but with a 10mm eyepiece it could be around 8mm. This distance (called eye relief by the way) can also vary with different eyepiece designs. Experimenting with what works best for you is the way to do it.

Try some experimenting during your next viewing session - there are no hard and fast rules on this or the eye closed / eye open thing, really.

[Ruud]

This will help:

It needs to bulge so that your lashes don't touch the patch because that's really irritating. I made one myself because the ones at the drug-store weren't comfortable enough. I have to make another one because I misplaced it.

It helps if you can keep both eyes open. Closing one eye causes strain and with less strain you see more.

[Pete Presland]

I have also used the eye patch method for extended sessions, the skull and crossbones though is purely optional

[Peter Drew]

If the telescope is a white tubed Newtonion, fit a patch of flocking material opposite the eye that you don't use, you won't "see" the tube then.

[Ruud]

How can you observe if you don't have a skull or bones?

You can do without the bottle of rum. It's empty in no time and afterwards you misplace your eye patch.

[DRT]

I'm a right eye observer and have never managed to master keeping the other eye open whilst observing.

I do like the idea of everyone at SGL-XI having to wear a skull and crossbones eye patch so we could tell the lefties from the righties

[jason.p]

Keeping both eyes open does come with practice so long as there aren't too many light distractions around. My early career involved hours of monocular microscopy and we had to learn to keep the both eyes open to avoid strain. Took a while but comes naturally now. Otherwise as Ruud says, try the eyepatch.

[Astro Imp]

I'm another who wears an eye patch without the skull and cross bones but my wife still asks where's the parrot 

[Peter Drew]

A wife with a sense of humour.  Priceless.

[Stu]

I think keeping both eyes open could work in very dark conditions, but where I observe it is just too distracting to keep both open. Patches are a good idea, but I normally forget or find it a bit of a faff, so I close my non observing eye.

[hawklord2011]

Looks like there's no right answer, I'll keep experimenting and keep that eye patch on standby

[rockystar]

I close one while I'm searching, but when I feel it starting to be a strain I use either cover the non-observing eye with my hand or pull my hood over the eye.

[Gazabone]

I always close one eye, I can hardly see a thing through the scope with both eyes open.

[Mak the Night]

I can often observe with one eye open, it is more restful with protracted sessions. Although mostly I tend to close my (left) eye and observe with the right instinctively more than anything else I think. Although this is one of the reasons I've acquired a bino viewer for lunar/planetary sessions.

[Paul73]

I'm a one eye squinter. I ocaisionally leave the other open as it seems to relax a tired observing eye.

For me, the two biggest things about eye positioning are:

1/ make sure that you are looking straight down the length of the eyepiece. Not craning to see.

2/ sit down when observing. Much easier to keep the head still.

Paul

[Astro Imp]

I'm a one eye squinter. I ocaisionally leave the other open as it seems to relax a tired observing eye.

For me, the two biggest things about eye positioning are:

1/ make sure that you are looking straight down the length of the eyepiece. Not craning to see.

2/ sit down when observing. Much easier to keep the head still.

Paul

This makes a huge difference.

[bingevader]

I wouldn't get too hung up on keeping both eyes open.

Do what is most comfortable for you.

Be that both eyes open, a patch, or a squint.

You're far more likely to have a good session doing what is comfortable rather than struggling with something uncomfortable.

I experimented with contact lenses for observing, to avoid taking my glasses on and off.

I made such a mess of my eye putting it in, I didn't get to see much at all!

[scarp15]

As above really, being comfortable at the eyepiece is relaxing and there is no eye strain. No particular principle, sometimes I do like to keep both eyes open, I often might wear a thin fleece cap, so simply lightly pull this over the non observing eye.  

[MountainSkies]

Helps with viewing, but don't keep both eyes open if uncomfortable.

 

TIP: put a hand over the other eye, as this helps!

[Stout Porter]

I have a hat that steps down to cover the ears, I just rotate it slightly and it covers one eye. Quick and easy to cover/uncover your eye, and keeps your head warm. Win win. ??

[trazor]

Many rifle shooters use a black shield fixed just in front of there open unused eye.

[Adamchiv]

On 17/01/2016 at 16:56, hawklord2011 said:

Happy if you can point to an existing post but the one thing I've struggled with (on admittedly my first and only observing session) was looking through the eyepiece consistently. I was either too close and moving the scope or too far away and not seeing everything. Also I've read a lot about keeping both eyes open but had to keep closing one as I couldn't get my 'star eye' to dominate and ended up looking at my scope! Are there any good tips on keeping both eyes open and also on the best distance to be from the eyepiece?

We close one eye naturally or move away from the eyepiece in mental discomfort because our brain isnt trained to let one eye look at our close proximity and the other into infinity. If you close one eye when looking into the eyepiece, the observing eye will vibrate and not give you as clear an image as with 2 eyes open. We have to train ourselves to use 2 eyes if we want to get the best image possible, the telescope finds looking into infinity a lot easier than our eyes do. Its much easier in total darkness to look with both eyes as the non observing eye doesnt have anything to really concentrate on. I find using 2 eyes very difficult, I find it similar to having a sugar coated donut without licking my lips, the brain will force us to do the most comfortable thing, its a brain led unconcious reaction to move away from the eyepiece that you have to force yourself to control and adapt to.

Adam

*sorry to actually answer your question I believe the answer is time and practice, which is what I am hopefully accumulating each time I observe

[SonnyE]

I just close my unused eye as I approach my eyepiece. Which is only really used during alignment for me. I'm not much of a visual observer.

I have a much harder time keeping track of my reading eyeglasses. Those drive me absolutely bonkers at times.

[Davesellars]

I cover my eye but keep it open.  I don't have a pirate eye patch but this works for some people.  I find keeping the unused eye open is a lot easier if you can block all external light from entering by covering it so your view is pitch black (unless you're blessed with observing in an LP free environment - I generally do this with either a fleece or towel over my head and wrapped over.   Blocking all external light from the possibility of entering your eye other than the light in the eyepiece will also increase the possibility of detecting fainter objects / detail.