Ch4 3D Optical Advice

In article , Roger
writes

"Dave W" wrote in message
...
Nobody has achromatic lenses in their eyes, i.e. red and blue need
different focus settings. The eyes of those under 40 adjust
automatically to suit the prevailing conditions, but pensioners like
me have lost the power of accommodation, and need different glasses
for different distances.

I found the right-eye blue image on Channel 4's 3D programmes badly
out of focus using my TV glasses.

So go to the opticians and have pair of glasses made from a correct
prescription - or a correct eye test. Avoid Specsavers as they use the
"nearest" that will do to save costs.

Rant missing the point snipped

No one else needs to do this - the problem is YOURS and only YOURS.
God knows why you think that your incorrect lenses in your glasses are
going to affect everyone else. If you need a new prescription go and get
it.
If you need to rotate a lens it shows you have astigmatism and the current
lenses are no good. If one eye and lens provides an image out of focus
compared to the other eye it means your sight has deteriorated since your
prescription or that your prescription does not match the lens.

No optician will prescribe lenses which fix the problem that the OP, and
myself, have and it ISN'T astigmatism. Try reading the first sentence
of his post again and it might help you understand the problem. The OP
may well be able to get very good, or at least acceptable, polychromatic
vision correction. However, when filtered to specific colours, the
correction is off. "Correct" glasses aren't going to fix this - as the
OP says, "nobody has achromatic lenses in their eyes" - and no optician
provides achromatic corrective lenses either!
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's ****ed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)

In article
,
Dave W writes
Nobody has achromatic lenses in their eyes, i.e. red and blue need
different focus settings.

Tell me about it. I started needing corrective glasses for reading a
few years ago, although my distance vision is still better than 20/20
which, contrary to popular opinion, is merely an acceptable standard and
not perfect vision.

However, when I rented a VW Passat a while back I noticed that I could
not read any of the red LED indicators on the dashboard at night without
my reading glasses, but while I couldn't read the blue LED indicators
*with* my reading glasses I could read them perfectly well without
glasses. In other words, I could focus closer with blue than with red
when it was relatively dark and my irises were wide open.

That led me to investigate further. The difference isn't so much in
daylight, in fact it is very difficult to detect at all. However once
the light levels drop so that my irises are open wide then it becomes
much more noticeable. Red focuses well at distance but require +2.5
diopter correction at arms length and more closer. Blue is the opposite
and focus well at arms length yet require -1 dioptre correction at
distance. Green seems to be ok at distance but requires about +1
diopter at arms length.


--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's ****ed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)

"Dave W" wrote in message
...
Nobody has achromatic lenses in their eyes, i.e. red and blue need
different focus settings. The eyes of those under 40 adjust
automatically to suit the prevailing conditions, but pensioners like
me have lost the power of accommodation, and need different glasses
for different distances.

I found the right-eye blue image on Channel 4's 3D programmes badly
out of focus using my TV glasses. I was able to solve the problem by
swinging my glasses off my right eye so that it saw the screen
directly through the blue filter. Both eyes saw a focussed image and
the 3D experience became a pleasure not a pain.

Those oldies who need glasses for everything would not be able to do
this - all they could do is use their distance glasses on their right
eye and their TV glasses on their left, probably looking through them
from front to back to keep the ear hooks out of their face.

Varifocal users might be able to rotate their glasses clockwise a bit
so that the right eye sees a weaker part of the lens.

Dave W



I was really looking forward to "Friday the 13th Part III (3D)" having so
much enjoyed Jaws III 3D and the the 3D adventures of the early 1980s when
everything worked perfectly.

Sadly, this week's Channel 4 3D week has been a failure for me and I've had
to abandon Friday the 13th after about 20 minutes.

I see a double image in most, but not all frames, and what I see has very
little 3D effect.

I believe the problem may be poor quality or sub-spec glasses. The blue lens
seems cloudy and obfuse to me compared to the clearer yellow lens.

I've tried adjusting it and cleaning it with no joy.

It's a relief to take the glasses off and get back to high quality (tongue
in cheek) digital terrestrial TV. *



* The over-compressed pixilated picture quality of yesterday's rugby match,
apart from the benefit of widescreen, was worse, nay far worse, than the TV
picture I used to have in the early 1980s using an indoor aerial. Pointless,
digital TV really is pointless.

On 22 Nov, 23:19, "Light of Aria"
wrote:
"Dave W" wrote in message

...



Nobody has achromatic lenses in their eyes, i.e. red and blue need
different focus settings. The eyes of those under 40 adjust
automatically to suit the prevailing conditions, but pensioners like
me have lost the power of accommodation, and need different glasses
for different distances.

I found the right-eye blue image on Channel 4's 3D programmes badly
out of focus using my TV glasses. I was able to solve the problem by
swinging my glasses off my right eye so that it saw the screen
directly through the blue filter. Both eyes saw a focussed image and
the 3D experience became a pleasure not a pain.

Those oldies who need glasses for everything would not be able to do
this - all they could do is use their distance glasses on their right
eye and their TV glasses on their left, probably looking through them
from front to back to keep the ear hooks out of their face.

Varifocal users might be able to rotate their glasses clockwise a bit
so that the right eye sees a weaker part of the lens.

Dave W

I was really looking forward to "Friday the 13th Part III (3D)" having so
much enjoyed Jaws III 3D and the the 3D adventures of the early 1980s when
everything worked perfectly.

Sadly, this week's Channel 4 3D week has been a failure for me and I've had
to abandon Friday the 13th after about 20 minutes.

I see a double image in most, but not all frames, and what I see has very
little 3D effect.

I believe the problem may be poor quality or sub-spec glasses. The blue lens
seems cloudy and obfuse to me compared to the clearer yellow lens.

I've tried adjusting it and cleaning it with no joy.

It's a relief to take the glasses off and get back to high quality (tongue
in cheek) digital terrestrial TV. *

* The over-compressed pixilated picture quality of yesterday's rugby match,
apart from the benefit of widescreen, was worse, nay far worse, than the TV
picture I used to have in the early 1980s using an indoor aerial. Pointless,
digital TV really is pointless.

Is the Digital Switchover ********?

Light of Aria wrote:


"Dave W" wrote in message

...
Nobody has achromatic lenses in their eyes, i.e. red and blue need
different focus settings. The eyes of those under 40 adjust
automatically to suit the prevailing conditions, but pensioners like
me have lost the power of accommodation, and need different glasses
for different distances.

I found the right-eye blue image on Channel 4's 3D programmes badly
out of focus using my TV glasses. I was able to solve the problem by
swinging my glasses off my right eye so that it saw the screen
directly through the blue filter. Both eyes saw a focussed image and
the 3D experience became a pleasure not a pain.

Those oldies who need glasses for everything would not be able to do
this - all they could do is use their distance glasses on their
right eye and their TV glasses on their left, probably looking
through them from front to back to keep the ear hooks out of their
face.

Varifocal users might be able to rotate their glasses clockwise a
bit so that the right eye sees a weaker part of the lens.

Dave W



I was really looking forward to "Friday the 13th Part III (3D)"
having so much enjoyed Jaws III 3D and the the 3D adventures of the
early 1980s when everything worked perfectly.

Sadly, this week's Channel 4 3D week has been a failure for me and
I've had to abandon Friday the 13th after about 20 minutes.

I see a double image in most, but not all frames, and what I see has
very little 3D effect.



Friday 13th Part 3 was a dire conversion. Firstly they had to deal with
a horrendously grainy print. It was awful. Secondly the conversion
from Polarised 3D to the ColorCode3D that channel 4 used was awful.
Conversion from the Red/Blue 3D of old would be more suited but Friday
13th was not filmed that way. The double image syndrome was more
visible during the darker scenes and as there was a lot of dark scenes
it seemed more noticable overall.

I too gave up after 20 minutes because to get any kind of decent 3D
effect you had to be almost on top of the TV but the print was so bad
it was unwatchable so close up (and I was watching on CH4 HD).


I believe the problem may be poor quality or sub-spec glasses. The
blue lens seems cloudy and obfuse to me compared to the clearer
yellow lens.


Me too. However, I think the quality of the conversion matters. It
was worse when programs were converted from other 3D formats but was
acceptable on original ColorCode formated programs like the Derren
Brown thing.


MC

Modern 3D TV when launched is likely to use circularly polarised
specs.

UKM

"UKMonitor" wrote in message
...
Modern 3D TV when launched is likely to use circularly polarised
specs.

I've always wondered about polarised 3D. In a cinema you can have two
projectors aimed at the screen, using polarising filters at 90 degrees to
each other. But how do you make a TV screen produced polarised light that
the polarised specs can separate into different left and right images?

"Martin" wrote in message
o.uk...

........... But how do you make a TV screen produced polarised light that
the polarised specs can separate into different left and right images?

2 TV sets, now there is a thought.
LOL

Regards
David

Martin wrote:

"UKMonitor" wrote in message

...
Modern 3D TV when launched is likely to use circularly polarised
specs.

I've always wondered about polarised 3D. In a cinema you can have two
projectors aimed at the screen, using polarising filters at 90
degrees to each other. But how do you make a TV screen produced
polarised light that the polarised specs can separate into different
left and right images?

Interlaced?

MC

Me too. However, I think the quality of the conversion matters. It
was worse when programs were converted from other 3D formats but was
acceptable on original ColorCode formated programs like the Derren
Brown thing.


MC


Thanks MC. I am glad it wasn't just me experiencing this. It was a joy to
get back to 2D 16:9 after this!