Which pictures are the eyestrainiest?

[DarkWalker]

It occurred to me you guys seem more comfortable with movement you're in control of. As well as the indirect control above, here's a version where the image moves randomly without human input:

• Image and viewscreen move randomly every 2 seconds

Is that easier or harder on the eye than the previous set?

I usually don't have problems with either focus or movement, but this one had me slightly nauseous after a time... not eye strain, though.

No effect from any of the other fixed or moving images.

On the other hand, I worked for a time with producing 3D images and animations (3D as in, jump into your face, use 3D glasses to see), and what seemed to cause people the most eyestrain was when the screen border cut out part of an object that is a bit more distant but still reasonably close (say, an approaching ship). So, you might want to use images with things in the foreground; your current mountain range image is pure background.

 

[Cathy]

Ok, so here are some versions where X and Y movement have been swapped (try moving the mouse straight left and right to see what I mean):

• X/Y switched, only the viewscreen moves
• X/Y switched, only the image moves
• X/Y switched, both move

Do those do anything for you?

These are all a bit woozy-making. Especially the first and third ones.

It occurred to me you guys seem more comfortable with movement you're in control of. As well as the indirect control above, here's a version where the image moves randomly without human input:

• Image and viewscreen move randomly every 2 seconds

Is that easier or harder on the eye than the previous set?

I have no trouble with this one. I just sit back and watch it do its thing, and it doesn't give me any unpleasant sensations. Maybe it's because I'm not trying to make it go anywhere?

 

[Andrew Sayers]

Sorry for leaving this thread so long.

I worked for a time with producing 3D images and animations (3D as in, jump into your face, use 3D glasses to see), and what seemed to cause people the most eyestrain was when the screen border cut out part of an object that is a bit more distant but still reasonably close (say, an approaching ship). So, you might want to use images with things in the foreground; your current mountain range image is pure background.

That's interesting, and sounds similar to the previous experiment up the thread. I think we're actually looking at two unrelated issues, and the mountain issue is triggering one but not the other...

Some people suffer from eyestrain. It seems the best way to express this to a developer is that the act of refocussing between "near" and "far" is an expensive operation for these people, and it can be triggered by fairly complex stimuli such as a dashboard - essentially people don't see these as nearby so much as they remember them that way. In crude gamey terms, if their eyes were weapons they would have a limited energy bar that got depleted every time they switched between elements designed to look close and those designed to look far away. Once their refocus energy is used up, their eyes need an extended cooldown period to replenish that energy.

Other people suffer sea sickness. This seems to be linked to a far more primitive part of the brain that just processes movement. The experiments so far suggest it has something to do with motion that can't be correlated directly to actions, but I'm not yet clear on the details.

Here are a couple more experiments that might help firm up the above...

I'd really like to know if the brain just needs time to adjust to sea sickness. Please let me know if you have any problems with the following:

• Image and viewscreen move randomly, with a 0.05 second pause between movements
• Image and viewscreen move randomly but naturalistically
• Image and viewscreen move randomly but naturalistically, with a 0.05 second pause between movements

Second, a real world experiment:

Get two pieces of paper and write your name on each one. Put one at the other end of the room and hold the other in front of you. Read your name first off the near one, then the far one, then back to the near one and so on. Does that trigger eyestrain, and if so how does it compare to the eyestrain caused by images on a screen?​

 

[Cathy]

Ok, so here are some versions where X and Y movement have been swapped (try moving the mouse straight left and right to see what I mean):

• X/Y switched, only the viewscreen moves
• X/Y switched, only the image moves
• X/Y switched, both move

Do those do anything for you?

One is a bit weird, two is less weird, number three is very weird. They're not eyestrainy but disorienting.

 

[Cathy]

• Image and viewscreen move randomly, with a 0.05 second pause between movements
• Image and viewscreen move randomly but naturalistically
• Image and viewscreen move randomly but naturalistically, with a 0.05 second pause between movements

The tiny pause definitely makes it easier to follow.

Second, a real world experiment:

Get two pieces of paper and write your name on each one. Put one at the other end of the room and hold the other in front of you. Read your name first off the near one, then the far one, then back to the near one and so on. Does that trigger eyestrain, and if so how does it compare to the eyestrain caused by images on a screen?​

Repeated rapidly over time (several minutes) it makes my eyes tired. Images on a screen have a similar affect if they display a scene representing something in the near foreground and something in the distance, but I don't get eyestrain from looking at a computer screen in general (e.g. I can write for hours with no ill effects).

 

[Aewarin Jameson]

PacalB linked this in a different thread.

All is fine with it.

However, speed up the movement (slider about 5/6th the way on the right) and my stomach complains

A lot of what you have been showing, for me, relates to the speed at which I can process what I see .. movement that's irregular but slow is fine, same movement sped it is not. Odd

 

[Andrew Sayers]

PacalB linked this in a different thread.

All is fine with it.

However, speed up the movement (slider about 5/6th the way on the right) and my stomach complains

A lot of what you have been showing, for me, relates to the speed at which I can process what I see .. movement that's irregular but slow is fine, same movement sped it is not. Odd

You know what's really freaky? I watched it at full speed all the way then paused it. Now I stare into the centre of it and my brain is convinced it's slowly zooming out.

It sounds like the way to think about sea sickness is that the brain has sort of an internal buffer for processing movement, and when that buffer overflows it creates a queasy feeling. So the devs need to fill it up less (e.g. let people turn off redundant movement) and give them opportunities to flush that buffer (e.g. insert gaps between movement).

If that makes sense to you guys, I'll paste it into the open design discussion thread in case they're not monitoring this one. Hopefully expressing issues mechanically will give them enough to chew on to make a good decision.

 

[Slawkenbergius]

You know what's really freaky? I watched it at full speed all the way then paused it. Now I stare into the centre of it and my brain is convinced it's slowly zooming out.

I got an effect similar to that. It's almost but not quite the vertigo effect, where the outside of the frame stays quite static, but the middle moves away. Not quite as pronounced though.

Perhaps that piece of art could work well to test people's relative tracking/processing capabilities... There are quite a few bits of written word in the pictures. Turn the speed up to full, and try and catch what's written on the stripy hat. Watch through more than once if you don't get it first time round. Answer below:

Spoiler

Read books

 

[Andrew Sayers]

If that makes sense to you guys, I'll paste it into the open design discussion thread in case they're not monitoring this one. Hopefully expressing issues mechanically will give them enough to chew on to make a good decision.

I decided to post while it was fresh in my mind - here's the summary in the open design discussion thread.

Massive thanks to everyone that contributed - your hard work has let me express the issues in a way I really hope Frontier will be able to make use of.

 

[Cathy]

Great job, Andrew

 

[DarkWalker]

Here are a couple more experiments that might help firm up the above...

I'd really like to know if the brain just needs time to adjust to sea sickness. Please let me know if you have any problems with the following:

They all still have me feeling slightly uncomfortable after a time, though the pause and the easing do help.

My guess is that having no control over the timing of the shifts is what triggers it, for me at least. I don't have any issue with motion sickness when I control the motion, even if the direction of motion is random and the only things taken from my input are the timing and speed. Also, in the real world, I can get motion sickness from riding a car as a passenger while not having any issue with actually driving that same car.

(BTW, if anyone knows the game, I used to play Aliens vs Predator multiplayer, nearly always using the Runner alien, always moving at top speed and abusing the jump to make myself a harder target; this is why I think the lack of control is what triggers it for me, since as far as merely shifting scenes go I doubt you could make something worse than what I already put myself through in my regular gaming. I literally had friends get motion sickness from watching me play )

Second, a real world experiment:

Get two pieces of paper and write your name on each one. Put one at the other end of the room and hold the other in front of you. Read your name first off the near one, then the far one, then back to the near one and so on. Does that trigger eyestrain, and if so how does it compare to the eyestrain caused by images on a screen?​

This one I don't even have to test. My current workplace has my computer at the back end of a 50m long building, facing the front (and the street) with an unobstructed view. I pass the whole day re-focusing my eyes on objects varying in distance from 50cm to more than 50m. This kind of eyestrain is something I really don't have (and that I doubt I will ever develop, after all my eyes get solid "training" every day).

 

[Cathy]

This one I don't even have to test. My current workplace has my computer at the back end of a 50m long building, facing the front (and the street) with an unobstructed view. I pass the whole day re-focusing my eyes on objects varying in distance from 50cm to more than 50m. This kind of eyestrain is something I really don't have (and that I doubt I will ever develop, after all my eyes get solid "training" every day).

That kind of environment can in fact be good because you're relaxing the lens muscles in your eyes every now and then, at your own pace, and in a real setting. For people who suffer eyestrain from prolonged close-up work, that kind of seating position is often recommended.