Planetary Preview...

I agree with Quarto partially. From the view that Howard Day provided you would likely not see any type of specular reflection. However from a much closer view that Brad showed there would be a noticeable reflection. I think the key here between the two pictures is the distance. From a view in which you could see the entire circle of the planet you shouldn't see any spec reflection. However when your viewpoint is as close to the planet as in Brad's picture (say from low orbit) the spec would be noticeable. I'm not sure if I'm explaining myself very well here but I think you get my point.
 
Yes, I agree. I think distance is the reason why that spec looks out of place in Howard's renders, along with the lack of clouds to partially hide it.

Even in Brad's close-up shots, the intensity seems lower (and I think that in the last shot Brad posted it's just the atmosphere that's turning everything brighter and bluer around the edges of the planet, but maybe that's just me :p).
 
Why wouldn't you see specular farther away? There's no pyhsical property of light that I'm aware of that would do that. In fact, I have some pictures at home with the spec plainly visible from the moon.
http://nssdc.gsfc.nasa.gov/image/planetary/earth/apollo08_earthrise.jpg
http://nssdc.gsfc.nasa.gov/image/planetary/earth/gal_earth_moon.jpg
http://blog.doctissimo.fr/php/blog/pensees_emotionnelles/images/Paysage - NASA earth,vulcano.jpg
Even this one - you can see the spec peeking out from behind the right side of the African continent.
http://www.solarviews.com/raw/earth/earthafr.jpg
So I think the problem here is the understanding of exactly how reflective water is. That's what you're seeing here - the reflection of the sun.
Now I'll agree that it still needs to be perfected and tweaked, but a specular reflection isn't just going to go away as you get farther from the planet. It will however lessen as the angle of the viewer to the surfce of the planet becomes perpendicular. That's still not going to make it dissapear, though.
Anyhow, I'll tweak it when I get home :D
 
There's an abundance of shots out there to reference from, I found these two:

http://www.organiccoffeeroaster.com/earth.jpg

http://osiris.rutgers.edu/~smm/art/earth.jpg

In this one especially you can see the absence (or to the point of being only barely detectable by the human eye) of the spec. At any case, I'm just suggesting that the spec be very faint and not overly pronounced. I'm not sure many people would even notice if it were missing...but they will notice if it is highly accented.
 
Heh, heh. You do realize that the reason no spec is visible in those shots is because Africa is overlapping the ocean, right? The spec spot would go smack damn in the middle of the continent. Land doesn't reflect light like the ocean does. You can see the spec starting to build up off the east coast of Africa - it just doesn't build up all the way because it hits land.
 
Howard Day said:
Why wouldn't you see specular farther away? There's no pyhsical property of light that I'm aware of that would do that. In fact, I have some pictures at home with the spec plainly visible from the moon.
http://nssdc.gsfc.nasa.gov/image/planetary/earth/apollo08_earthrise.jpg
http://nssdc.gsfc.nasa.gov/image/planetary/earth/gal_earth_moon.jpg
Those shots are pretty much how I think the spec should look, and it's what I tried to make it look like in Standoff:
earth_ep5_m5_preview.png

Ignore the stuff that's blowing up and affecting the lighting a bit... Notice that it still looks softer than the highlights you had there.

I'm not sure what law of physics dictates this... but the spec in those shots you posted is not as bright as when you look down to the sea from an airplane. :p So altought I'm no expert on the subject, I suspect that either the distance or a byproduct of it, like how much stuff (ie: atmosphere) there is between the sea and the camera, has an effect on the highlights.
 
Howard Day said:
http://blog.doctissimo.fr/php/blog/pensees_emotionnelles/images/Paysage - NASA earth,vulcano.jpg
Even this one - you can see the spec peeking out from behind the right side of the African continent.
http://www.solarviews.com/raw/earth/earthafr.jpg
So I think the problem here is the understanding of exactly how reflective water is. That's what you're seeing here - the reflection of the sun.
Now I'll agree that it still needs to be perfected and tweaked, but a specular reflection isn't just going to go away as you get farther from the planet. It will however lessen as the angle of the viewer to the surfce of the planet becomes perpendicular. That's still not going to make it dissapear, though.
Anyhow, I'll tweak it when I get home :D

I think most of the photographs there show considerably less reflection than your latest Pioneer planet shots.
 
Perfect! Alright, here's my data. here's the link to the visible light record from the GOES 8 weather satellite. You can plainly see the specular in the images - and you were all right - I was using too much. I've since toned my materials down...
http://www.ssec.wisc.edu/data/geo/east/
(You may have to set it to "visible Light" and "full disk" and tell it to animate...pretty cool stuff there. :D )
 

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Let me echo the thoughts of the others, that last is a great shot. Of course it also includes clouds which I'm sure makes a big difference as well.
 
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