Jump to content

SkySurveyBanner.jpg.21855908fce40597655603b6c9af720d.jpg

Eyes get better or worse doring nights?


lulaz

Recommended Posts

Hello to everyone!

I'm new into astronomy and it has been just a few days that I started to look at the night sky...

During the nights, I realized something interesting about my eyes: on the start of observation, I could see only a few amount of stars (I live in São Paulo (Brasil), so that has a LOT of luminar pollution). As the time passed, I could see more stars and I felt that my eyes got better during the night long.

Unfortunately, when I woke up the next day, my vision become normal again.

I know that some of this "better vision" was because of the darkness of the night, but what do you guys think? that a lot of nights the vision become better and better (because you get used to see "more" with less light) or worse becouse you stress :) your eye too much?:)

Link to comment
Share on other sites

The nerves in the eyes translate light to the brain along the optic nerve from "Rods" and "Cones". The cones are in a densley packed area in the back of the eye and are specifically to translate colour. The "Rods" are a lot fewer and spread out more around the cones and are specifically picking up dark shades.

When you are in a dark field for around 20 mins - the cones become inactive (no colour to trigger them). And you are seeing with the rods only. This is called "Dark Adaption" or "Night Vision". Unfortunately if you see a light (eg cigarette lighter or car headlight) the cones get trigerred again and you need to wait another 20 mins before you are once more dark adapted.

There's no stress to the eye and you see a lot more in the dark when dark adapted hence it's much better for astronomy :)

Link to comment
Share on other sites

Also - when you are using "averted vision" you look to the side of an object to see it better. Effectively you are tilting your eye so the rods are picking out the darker shades of your object - most stuff up there is dark with very faint shades of light :)

Link to comment
Share on other sites

Hello to everyone!

...but what do you guys think? that a lot of nights the vision become better and better (because you get used to see "more" with less light) or worse becouse you stress :) your eye too much?:)

Hi Lulaz,

An interesting question...

In my opinion you certainly become a better observer as you get used to looking for small, feint objects. Observing the night sky also teaches you how to look more carefully, and maybe over a long period you also learn to become more objective about exactly what it is you are seeing. It's been said on here before that there's a difference between observing, and 'just looking', and for me that sums it up just nicely.

I don't know if there are any long-term benefits, but I can't think how it could make your eyesight any worse. So long as you're not using unsuitable or defective optical aids, and as long as you're not squinting when you observe, then you shouldn't be stressing your eyes. :p

Link to comment
Share on other sites

Younger people have fitter eye muscles so they are more capable of wider pupils than say a middle aged person - and hence their retinas gather more light. That's why I often wish I'd taken up astronomy at a younger age lol :)

Link to comment
Share on other sites

  • 2 weeks later...

Hi Lulaz

It is an interesting discussion. I know my eyesight is slowly changing and it isn't getting any better, but after observing for over 5 years mostly on double stars I can see closer doubles more easily now as my brain is 'trained' to spot what they look like :)

One way I use to explain it. You look with your eyes but you see with your brain :mad:

Cheers

Ian

Link to comment
Share on other sites

Hi Lulaz

It is an interesting discussion. I know my eyesight is slowly changing and it isn't getting any better, but after observing for over 5 years mostly on double stars I can see closer doubles more easily now as my brain is 'trained' to spot what they look like :mad:

One way I use to explain it. You look with your eyes but you see with your brain :D

Cheers

Ian

yeah! I think "to look" is different from "to see"... I believe that everyone can just look, but to see and feel the good sensation when we look at stars (with or without accessories) is totally different! I think it is a bless that we, amateur astronomers, can see and feel this sensations!

PS: I hope that I could express myself! languages that came from latin are very emotional, and we can express ourselves easly... but I don't know such words for english =S

Thank you Ian, Brantuk and Tantalus!!! :)

Link to comment
Share on other sites

Eyes can get better, occasionally. For many years I have been slightly short sighted - enough for my optician to recommend glasses for reading, TV, computer and driving. When I had them tested last year, she advised that they were much better than before and suggested doing away with glasses. Having worn them for nearly 10 years, I felt a bit 'naked' driving without them at first!

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.