Screen Luminance

[[email protected]]

Anybody could tell me how the "nits" related to the standard measure
of Luminance "cd/m2" (candela per square meter) ?
I have seen in this forum, that for example the brightness of the
Clearnav and Ultimate is about 1000-1500 nits as somebody said, but
how much is in cd/m2 ?
A TFT screen with 300 candela per square meter is readable in direct
sunlight ?
Maybe stupid questions ?

[Darryl Ramm]

On Oct 10, 1:08*pm, wrote:
> Anybody could tell me how the "nits" related to the standard measure
> of Luminance "cd/m2" *(candela per square meter) ?
> I have seen in this forum, that for example the brightness of the
> Clearnav and Ultimate is about 1000-1500 nits as somebody said, but
> how much is in cd/m2 ?
> A TFT screen with 300 candela per square meter is readable in direct
> sunlight ?
> Maybe stupid questions ?

Google "nit candela", click on the top link. Pretty easy.

A nit is a candela per square meter.

What is readable in direct sunlight is not just captured by the nit
rating. A lot depends on contrast, type of display, surface
reflections, color properties of the display, and especially *your*
eyesight. So if screen visibility is a big issue to try to find a way
to look at the displays.

Darryl

[Jay Pokorski]

On Oct 10, 4:20*pm, Darryl Ramm > wrote:
> On Oct 10, 1:08*pm, wrote:
>
> > Anybody could tell me how the "nits" related to the standard measure
> > of Luminance "cd/m2" *(candela per square meter) ?
> > I have seen in this forum, that for example the brightness of the
> > Clearnav and Ultimate is about 1000-1500 nits as somebody said, but
> > how much is in cd/m2 ?
> > A TFT screen with 300 candela per square meter is readable in direct
> > sunlight ?
> > Maybe stupid questions ?
>
> Google "nit candela", click on the top link. Pretty easy.
>
> A nit is a candela per square meter.
>
> What is readable in direct sunlight is not just captured by the nit
> rating. A lot depends on contrast, type of display, surface
> reflections, color properties of the display, and especially *your*
> eyesight. So if screen visibility is a big issue to try to find a way
> to look at the displays.
>
> Darryl

Bottom line, I've had no trouble reading the ClearNav display in the
cockpit through sunglasses with dense mountainous terrain displayed.
Better than anything else I've seen.

Best regards,

Jay
R6

[Richard[_1_]]

On Oct 10, 1:08*pm, wrote:
> Anybody could tell me how the "nits" related to the standard measure
> of Luminance "cd/m2" *(candela per square meter) ?
> I have seen in this forum, that for example the brightness of the
> Clearnav and Ultimate is about 1000-1500 nits as somebody said, but
> how much is in cd/m2 ?
> A TFT screen with 300 candela per square meter is readable in direct
> sunlight ?
> Maybe stupid questions ?

1 Nit = 1 cd/m2 Candela per square meter.

The Craggy Aero Ultimate is adjustable with a max of 1800 nits. The
type of coating on the screen also imporve the sunlight viewability.

There is no difference between sunlight and shade with the Ultimate.

Please see the shade line http://www.craggyaero.com/ultimate.htm
second picture on the right.

Richard
www.craggyaero.com

[[email protected]]

Richard,
What type of screen are you using for Ultimate ?

[Bill Daniels]

"Jay Pokorski" > wrote in message
...
On Oct 10, 4:20 pm, Darryl Ramm > wrote:
> On Oct 10, 1:08 pm, wrote:
>
> > Anybody could tell me how the "nits" related to the standard measure
> > of Luminance "cd/m2" (candela per square meter) ?
> > I have seen in this forum, that for example the brightness of the
> > Clearnav and Ultimate is about 1000-1500 nits as somebody said, but
> > how much is in cd/m2 ?
> > A TFT screen with 300 candela per square meter is readable in direct
> > sunlight ?
> > Maybe stupid questions ?
>
> Google "nit candela", click on the top link. Pretty easy.
>
> A nit is a candela per square meter.
>
> What is readable in direct sunlight is not just captured by the nit
> rating. A lot depends on contrast, type of display, surface
> reflections, color properties of the display, and especially *your*
> eyesight. So if screen visibility is a big issue to try to find a way
> to look at the displays.
>
> Darryl

Bottom line, I've had no trouble reading the ClearNav display in the
cockpit through sunglasses with dense mountainous terrain displayed.
Better than anything else I've seen.

Best regards,

Jay
R6


Getting enough screen brightness to be viewable in direct sunlight is
relatively easy. Doing it at a reasonable current draw is the hard part.
Most of these 1000 nit plus screens draw around an amp at full brightness.

[Richard[_1_]]

On Oct 10, 2:10*pm, wrote:
> Richard,
> What type of screen are you using for Ultimate ?

The screen is proprietary but the specs are on my web site.

Richard
www.craggyaero.com

[sisu1a]

> Doing it at a reasonable current draw is the hard part.
> Most of these 1000 nit plus screens draw around an amp at full brightness.

Yeah, but if you can afford the Craggy or the ClearNav you can also
afford to buy the LiFePO4 batteries to double your amp hours for the
same weight as your lead bricks, not to mention adding 5-20W (or more)
of on-board solar to boot...

-Paul

[[email protected]]

Richard,
What does it mean ?
"The screen is proprietary but the specs are on my web site."
Are you saying that the TFT is not from China or Taiwan ? I think all
the TFTs, from the smallest to the largest are made there. If you
browse the www.globalsources.com, you can find hundreds of suppliers.
Which one are you using for the Ultimate :))) ?
btw. this is not a bad thing at all, setting-up nice things from
standard parts avaliable form the market and adding value to it, I am
just curious.

[Peter Purdie[_3_]]

I have measured the ClearNav on full brightness at 605mA, on power save
where it drops back to 'low', still easily bright sunlight readable,
until you press a button, below 400mA.

The figures from Craggy gave the Ultimate as about One and a half Amps,
but I haven't seen any independant measurement. For a screen that big and
bright with touch screen, that sounds about right.

At 01:21 11 October 2008, sisu1a wrote:
>> Doing it at a reasonable current draw is the hard part.
>> Most of these 1000 nit plus screens draw around an amp at full
>brightness.
>
>
>

[Richard[_1_]]

On Oct 11, 12:07*am, wrote:
> Richard,
> What does it mean ?
> "The screen is proprietary but the specs are on my web site."
> Are you saying that the TFT is not from China or Taiwan ? I think all
> the TFTs, from the smallest to the largest are made there. If you
> browse thewww.globalsources.com, you can find hundreds of suppliers.
> Which one are you using for the Ultimate :))) ?
> btw. this is not a bad thing at all, setting-up nice things from
> standard parts avaliable form the market and adding value to it, I am
> just curious.

The Ultimate Screen is a TFT Screen. Again the coatings and backlight
make all the difference I don't believe the backlight has as much
effect as the coating on the sunlight viewability. It is clearly
better the the ClearNav as it has 4 time the resolution True VGA and
is 6.5" on the diagonal, 1" larger than the ClearNav (this may be good
or bad depending on the size of your panel) and has the ability to
have a higher backlight. I have seen the ClearNav although it was
only in a panel on the table. Several pilots that saw both commented
on the Ultimate's superior display and the fact that it runs state of
the art software.

The Ultimate and the processor draw about 400 mAmp at the lowest
screen backlight (probalby not usable) at about 600 mAmp it is in my
opinion usable, full Backlight about 1800 nits 1600 mAmp (1.6 Amp).
I beleive the backlight a 1000 mAmp is extremely viewable. . This is
measured on a bench test.

I have about 70 hours of testing including about 30 hours in the 2008
US Sports Class Nationals, in my Ventus b, and used on the highest
backlight setting. The battery used was a 12V 8 amp Hour running the
Utlimate and a MicroAir radio. My other battery ran the CAI 302 and
CAI 303. I had no problems with a 6 hour flight.

Richard
www.craggyaero.com

[[email protected]]

Dear Rischard,
Thanks for your comments about the power consuption, this is very
useful information, anyhow I was not able to figure out the answer to
my previous questions related to the display.