Low-light colour blindness?

[cajen2]

Am I the only one with this problem?

I keep reading (here and in books) about stars which are deep blood red, dazzling blue, etc. I also note some people say they can see reds and greens in M42, for example. I'm not talking about long-exposure images here, but I can't see any of these colours - everything looks white to me. I tried to persuade myself that Aldebaran, for instance, was really orange-red but I'm not convinced. This seems to be true at any magnification too.

In normal light, I'm not colour blind or have any trouble distinguishing colours. Is there a condition like mine at low light?

[Dave scutt]

I have problems seeing any colour's too.

If you can't see the number in the image like me your coloured blind. 

[Sunshine]

It could very well be a characteristic of the particular optics involved as some telescopes display warmer or much colder color tones than others, I’m just guessing here but it may have something to do with it.

[Sunshine]

5 minutes ago, Dave scutt said:

I have problems seeing any colour's too.

If you can't see the number in the image like me your coloured blind. 

I see a whole range of green, orange and brown dots of different shades there but a number doesn’t exactly pop out except a 3 within the orange dots, is that it? 

[Dave scutt]

2 minutes ago, Sunshine said:

I see a whole range of green, orange and brown dots of different shades there but a number doesn’t exactly pop out except a 3 within the orange dots, is that it? 

Don't know can't see it🤣

[Sunshine]

Here’s another test I found online from a credible site. If you can read the text chances are you’re not color blind it states.I guess I’m not color blind as the text hit me right away without question.

Edited January 23, 2022 by Sunshine

[Dave scutt]

4 minutes ago, Sunshine said:

Here’s another test I found online from a credible site. If you can read the text chances are you’re not color blind it states.

No can't make out anything 

[PeterW]

I am not colourblind and there’s no numbers present in that picture. In low light everyone is colour blind, only the brightest objects can stimulate the coloured cone cells. Reiner Vogels physiology of vision makes for a good read. http://www.reinervogel.net/index_e.html I have heard they there are tricks for making star colours more obvious, though I am not sure of the details, maybe a little refocusing.

 

Peter

[Sunshine]

1 minute ago, Dave scutt said:

No can't make out anything 

Wow! I find that fascinating as it is smacking obvious to me, the difference between the dots that make up the text and the surrounding dots is red/orange text and green backdrop. So I guess it means you are red color blind.

[Dave scutt]

3 minutes ago, Sunshine said:

Wow! I find that fascinating as it is smacking obvious to me, the difference between the dots that make up the text and the surrounding dots is red/orange text and green backdrop. So I guess it means you are red color blind.

Does it say I need a new scope

[Sunshine]

1 minute ago, Dave scutt said:

Does it say I need a new scope

No but one never needs an excuse for a new scope!

[Deadlake]

11 minutes ago, PeterW said:

I am not colourblind and there’s no numbers present in that picture. In low light everyone is colour blind, only the brightest objects can stimulate the coloured cone cells. Reiner Vogels physiology of vision makes for a good read. http://www.reinervogel.net/index_e.html I have heard they there are tricks for making star colours more obvious, though I am not sure of the details, maybe a little refocusing.

 

Peter

Ha Ha colour scoptic vision. 😃

[PeterW]

Reiner Vogels comment on the relative sensitivity difference ofnrod and cones being about 5 mags..:

…” This reduction in sensitivity by about 5 mag can be easily verified in practice. Under good rural skies, the dark adapted eye can see stars down to about mag 6. They are detected with the rod cells (and peripheral vision, another topic) and appear gray, no color. In order to see star colors, we need our cones. With the 5 mag difference in sensitivity, we should be able to see star colors for stars of mag 1 and and brighter, which is confirmed in practice.“….

Hence you’re only likely to see colours in the very brightest objects.

Peter

[cajen2]

20 minutes ago, Sunshine said:

Here’s another test I found online from a credible site. If you can read the text chances are you’re not color blind it states.I guess I’m not color blind as the text hit me right away without question.

Had no problem with that one.

As I said, it only seems to happen at low light levels. Very frustrating when books tell you how gorgeously red, blue, etc something is.

[johninderby]

Also depends on how the screen you are looking at displays colours. Little tweaking of the colours makes a big difference.

[Dave scutt]

21 minutes ago, johninderby said:

Also depends on how the screen you are looking at displays colours. Little tweaking of the colours makes a big difference.

No still can't see it.

Does that one say I need a Tak

[johninderby]

3 minutes ago, Dave scutt said:

No still can't see it.

Does that one say I need a Tak

You mean a Tic-Tac? 😁

[Dave scutt]

Got that for Christmas because santa couldn't read

[PeterW]

No numbers in the circular image above reported by a certified deuteranope, not sure which type you’re looking to diagnose.

 

peter

[Stu]

1 hour ago, Dave scutt said:

I have problems seeing any colour's too.

If you can't see the number in the image like me your coloured blind. 

This is the full test, I think the one above is mean to show nothing if you are not colour blind…

https://www.challengetb.org/publications/tools/country/Ishihara_Tests.pdf

[Dave scutt]

I just picked that one because it was the first one I came too,didn't know if it had a number because I couldn't see a number in any of them

[Captain Scarlet]

6 minutes ago, Stu said:

This is the full test, I think the one above is mean to show nothing if you are not colour blind…

https://www.challengetb.org/publications/tools/country/Ishihara_Tests.pdf

Is that the mythical "double blind" test? ... I always have to stop and think really hard when presented with double-negatives

Edited January 23, 2022 by Captain Scarlet

[Captain Scarlet]

... seriously though. My wife has extremely sharp vision, she can see stars naked eye well beyond me. And out birding, she notices "bird action" far more sensitively than I or any other birders we've been out with. But she cannot see any colour whatsoever in Betelguese or Aldebaran, naked eye or through any sort of optics.

[Carbon Brush]

@Captain Scarlet comment. Been there and got the T shirt!
I believe there are lots of variations on our colour perception and vision generally.
We also have differences in low light resolution.

My wife can pick out visual doubles better than I can.
When looking at birds, I know it is a bird because it doesn't fly like a bat - but she recognises the type.
When scuba diving she was always the 'interesting marine life' spotter when I continued unaware.

Having said this. CAA medical examiners always thought my eyesight good enough to pilot a plane - including at night.
Oh yes. I can reverse park into the garage, but she can't!

[JOC]

IIRC from my A level biology class, the rods are responsible for black and white and the cones are for colour vision.  At low light levels we were told that because rods are more sensitive to light levels than cones our vision would become progressively more black and white as light levels deminished.  I can vividly!  remember being set homework to just go outside as the sun went down and then to report what we became aware of.  Without exception none of the class spotted it, but the answer was supposed to have been that what we saw went to gray scale as the darkness came.  Whether that explains some of what is discussed above I don't know, but I obviously learned what we were intended to learn as I can still recall the fact and the homework to this day.