why is telly more flickery from a distance than up close?

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ok i just qwent up on the roof to take my washing in off the line, and it is night and i have a fine view into the new flats three blocks away and ppl are watchin TV on their big screens

up close TV is normal and we watch it fine - but from far it is jerky and flickery

― mark s (mark s), Sunday, 24 July 2005 21:08 (twenty years ago)

explain me this and win my love

― mark s (mark s), Sunday, 24 July 2005 21:08 (twenty years ago)

its something to do with refresh rates and persistance of vision, i'll bet

― jermaine (jnoble), Sunday, 24 July 2005 21:15 (twenty years ago)

say more

― mark s (mark s), Sunday, 24 July 2005 21:21 (twenty years ago)

186,000 miles per second is slower than you think.

― Truckdrivin' Buddha (Rock Hardy), Sunday, 24 July 2005 21:22 (twenty years ago)

so is it the same reason stars twinkle?

― mark s (mark s), Sunday, 24 July 2005 21:24 (twenty years ago)

stars twinkle cuz of DEEP SCRATCHES ON YOUR CORNEA

― 2, Sunday, 24 July 2005 21:39 (twenty years ago)

it's the redshift doppler phenomenon

― Aaron A., Sunday, 24 July 2005 21:42 (twenty years ago)

CORNEA INDIE FUXXOR

http://org.ntnu.no/samfundet/samfundet-flyttet/db/bilder/film/clockwork_orange_plakat2.jpg

― mark s (mark s), Sunday, 24 July 2005 21:49 (twenty years ago)

The flicker-fusion threshhold.

― Michael Daddino (epicharmus), Sunday, 24 July 2005 22:02 (twenty years ago)

I was going to guess that you notice the flicker more because it is across a smaller proportion of your visual field.

― Tumililingan (ex machina), Sunday, 24 July 2005 22:04 (twenty years ago)

b-but surely the flicker is the same speed however far away the telly is?

(i assume the refresh of the whole screen is slower than eg the refresh of the smaller portion you are lookin at from normal distance at any given time)

― mark s (mark s), Sunday, 24 July 2005 22:05 (twenty years ago)

cf also those spooky blue lights in the cabs of big trucks (uk only?) which look like they move independently of the truck and are gazin from deeper inside the cab than the cab can be deep

― mark s (mark s), Sunday, 24 July 2005 22:08 (twenty years ago)

some questions are better left unasked, mark

― loggged out, Sunday, 24 July 2005 22:08 (twenty years ago)

speed of light vs speed of email response

― 2, Sunday, 24 July 2005 22:29 (twenty years ago)

right MARK?!!!!!

― 2, Sunday, 24 July 2005 22:29 (twenty years ago)

persistence of vision vs persistence of DELETE FEATURE

--- do i owe you a email 2@2? i have been a bit distracted lately :(

(i def owe G&W a post)

― mark s (mark s), Sunday, 24 July 2005 22:40 (twenty years ago)

did this get solved?

― mark s (mark s), Monday, 25 July 2005 07:58 (twenty years ago)

Our aerial is rubbish, but you can't see the telly through the window.

(Recommend me a good indoor aerial, please.)

― PJ Miller (PJ Miller 68), Monday, 25 July 2005 08:04 (twenty years ago)

tvs are also more flickery if you are eating crisps.

something to do with photons, probably. er, wave / particle duality. i wonder if it happens when you eat mash?

― koogs (koogs), Monday, 25 July 2005 08:14 (twenty years ago)

why are tv/puter screens always flickery when shown on tv?

why do car wheels look like they are going 'backwards?

tony conrad to thread!

― N_RQ, Monday, 25 July 2005 08:17 (twenty years ago)

cheese/onion duality

― mark s (mark s), Monday, 25 July 2005 08:18 (twenty years ago)

I read this as "what is more flickery from a distance than up close?" and I thought this topic was going to be a dirty joke.

― Cunga (Cunga), Monday, 25 July 2005 08:18 (twenty years ago)

saw both of N_RQ's questions on the first google result for 'tv flicker':

http://www.newton.dep.anl.gov/askasci/phy00/phy00469.htm

― koogs (koogs), Monday, 25 July 2005 08:50 (twenty years ago)

total coincidence!

you calling me a hack, koogs?

― N_RQ, Monday, 25 July 2005 08:53 (twenty years ago)

just trying to be helpful... 8)

― koogs (koogs), Monday, 25 July 2005 09:16 (twenty years ago)

If you watch digital TV upclose, it's all rectangles.

― jel -- (jel), Monday, 25 July 2005 15:42 (twenty years ago)

DVD's are the same.

― jel -- (jel), Monday, 25 July 2005 15:45 (twenty years ago)

that's bcz you've made yr eyes square jel

― mark s (mark s), Monday, 25 July 2005 15:58 (twenty years ago)

because when you're close, your pupils are dilating and contracting in response to the light - when you're far away, the ambient light is constant so you notice the flickering of the TV image.
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OK, I totally made that up.

― geyser muffler and a quarter (Dave225), Monday, 25 July 2005 16:23 (twenty years ago)

Could there have been a screen in their window that was interfering with the light?

― sleep (sleep), Monday, 25 July 2005 17:17 (twenty years ago)

Also PAL is always flickery! :P

― sleep (sleep), Monday, 25 July 2005 17:25 (twenty years ago)

i don't think there is but it's quite far away

anyway this always happens

― mark s (mark s), Monday, 25 July 2005 17:26 (twenty years ago)

>Also PAL is always flickery! :P

Flickery maybe, but lookit them lovely extra lines! So sharp! So crisp!

― Bill A (Bill A), Tuesday, 26 July 2005 10:56 (twenty years ago)

i would like to see this phenomenon demonstrated

― Britain's Jauntiest Shepherd (Alan), Tuesday, 26 July 2005 10:58 (twenty years ago)

I hate both PAL and Grime.

― Tumililingan (ex machina), Tuesday, 26 July 2005 11:04 (twenty years ago)

SECAM 4ever vous etes all gay.

― Alba (Alba), Tuesday, 26 July 2005 11:06 (twenty years ago)

it's got to be a function of inverse square law of energy dispersal and the persistance of vision - less light is getting to your eyes so there's less tendency for it to persist = flicker.

(the crisp thing, which is real, is, i think, something to do with vibrations in your head whilst munching)

secam is same number of lines and the same number of fields per second so would be just as bad as pal.

― koogs (koogs), Tuesday, 26 July 2005 11:15 (twenty years ago)

Never Twice the Same Colour.

It's rods'n'cones, innit? Smaller incident angle of image on retina from faraway object = fewer sensors processing it, flickering TV creates small-sample toggling type shenanigans. Or something.

kinda xpost

― Michael Jones (MichaelJ), Tuesday, 26 July 2005 11:16 (twenty years ago)

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