Visibility in FSX, from a meteorologists point of view

[Guest jan_berlin]

Hello to you all,I'm new to this forum, although I'm not new to FS. I'm flying FS since FS3, when I was a little child! I'm a meteorologist, and therefore I've been always interested in the representation of weather in FS very much. Do you remember the simple polygons representing clouds in FS4? Unbelievable how things have changed in FS over time.So let's talk about one thing that I would love to see being improved in FSX: Visibility! Visibility is one of the poorest graphical parts of FS weather so far, although effects look nice in static situations in low altitude. But once you ascend to higher altitudes things get worse and worse. The big problem seems to be that the graphics engine of FS so far is not able to handle zones of different opacity of the atmosphere at the same time, neither vertical nor horizontal.In the real world we have horizontal areas with different visibility, and additional to that vertical visibility changes. Normally there is a more or less shallow layer with poorer visibility (the boundary layer), and above visibility becomes much better, becoming excellent at very high flight levels.FS9 so far is not able to handle this correctly. Once you ascend above the boundary layer, the graphics engine suddenly sets the visibility to a very large global value to represent the clear air aloft. But as a consequence of this you're suddenly able to see the ground far far away, which is very unrealistic. If you descend back into the boundary layer, visibility becomes instantly very poor again. This (sorry!) really sucks. And there's another thing: if you ascend some 1000 feet above the boundary layer, FS9 tries to simulate poor boundary layer visibility by some sort of uniform ground based cloud layer. So far so good, but in hilly terrain this becomes really ugly, if some of the mountain tops are higher than the boundary layer, und you see these sharp edges where terrain exceeds the boundary layer.To improve visibility would be worth a new version for its own in my eyes because correct visualization of visibility could provide a very high amount of realism, think about convective situations for example. I know that this probably is a very difficult task and I also know that we don't have unlimited hardware power. But finding a way to handle different (at least: vertical!) visibility zones at one and the same time correctly would be more than a quantum leap forward.There are many many other topics about FS weather that we could talk about. But I think this is enough for my first post. :-) To be continued...Greetings from Berlin, Germany,Jan

[Guest Fjorko]

Hi mate !Firstly : Amen to everything you just said... I'm a frontrunner in supporting the idea that visibility needs fixing...Secondly: tdragger already said that it is a hardware fogging problem, and that they are working on it....so I am really hopeful that this can be sorted out in time for shipping.Cheers

[Guest jan_berlin]

Hi,>Secondly: tdragger already said that it is a hardware fogging>problem, and that they are working on it....so I am really>hopeful that this can be sorted out in time for shipping.okay, didn't read that. So there's hope that screens like this could belong to the past with FSX. :-)Jan

[Guest Peter Sidoli]

>There are many many other topics about FS weather that we could talk about. But I think this is enough for my first post. To be continued...

[Mace 1,902]

JanThe visibility problem is a problem that has been discussed here in the AVSIM FSX forum in the past few months in a few threads. I know the FS team is aware of it.The ONE suggestion I put in the fsteam's mailbox was to do something with the visibility. That shows how important I think it is to the overall sim.Rhett

[Guest Fjorko]

Yes, I'm sure they are well aware of it, and are giving their UNDEVIDED attention to it - aren't you tdragger !! ;-)

[michal 44]

>becomes much better, becoming excellent at very high flight>levels.Visibility can indeed be very good at high flight levels but it doesn't have to be so every single time. I was on quite a few commercial flights at FL350 and above where visibility would not be greater than say 10-20 miles. So yes, very often flying high gives you almost unrestricted visibility but it is not an absolute rule.This topic of visibility has already been mentioned on this forum quite a few times but it never hurts to hear from a real metereologist. ;)Fixing this problem would indeed be a huge step forward.Michael J.http://www.precisionmanuals.com/images/forum/pmdg_744F.jpghttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg

[Guest jan_berlin]

Hi Michael,>Visibility can indeed be very good at high flight levels but>it doesn't have to be so every single time. I was on>quite a few commercial flights at FL350 and above where>visibility would not be greater than say 10-20 miles. So yes,>very often flying high gives you almost unrestricted>visibility but it is not an absolute rule.You're right. In most cases this is because of thick cirrus cloud layers on top of thunderstorm clusters or frontal zones. As you certainly know visibility within the boundary layer often is restricted because the whole airmass is moist and hazy and not mixed out with the drier air above. I saw the top of the boundary layer as a passenger in a sailplane several times during summer. In these cases there's sometimes a pretty sharp (but of course not instant!! ;-) ) increase in visibility within some 100 feet altitude. In other cases there's a continuous increase in visibility from ground up to some 1000 feet altitude where the clear and dry air of the free atmosphere is reached. But you know better than me how that looks like, probably. :-)Here you can find a nice picture of what I'm talking about. A dusty boundary layer with some cumulus on top of it and the dry clear air above it.www-gte.larc.nasa.gov/dice/dice_photos/scenic/bndrylayercumulus.jpgIt would be a major step forward if only this could be visualized in a better way in FSX. And of course this cannot be done by just continuously adjusting the "global" visibility to greater values while ascending like some addons do it. The graphics engine has to handle smooth visibility layers and not just one like in FS9. Okay, probably a difficult task, luckily I'm not a graphic programmer! ;-) Good luck to the MSFS team to find the magic way to solve this!In any case, I'm looking forward to FSX,Jan

[Guest tdragger]

No, that's a different issue. That's a 2D texture we apply to the top of a visibility layer so you can see it before you entering it from the top.

[Guest jan_berlin]

Hi,>No, that's a different issue. That's a 2D texture we apply to>the top of a visibility layer so you can see it before you>entering it from the top.yes, I already assumed this effect to be 2D because the visual effect on the terrain below is the same regardless how far it is below the top of the layer. So FS9 simulates different visibility layers by setting the one and only visibility to some value and places these 2D textures on top of layers with lower visibility that otherwise would be invisible.I don't know wether this is a different issue, maybe it is. But in the end most of the discussed visibility problems are caused by the same problem: FS9 isn't able to deal with more than one visibility value for the whole atmosphere viewing from a certain point at a certain time. Clouds and the 2D textures mentioned above excluded. Is that right?Jan

[Guest thefringe]

I will suggest a change that has not been requested thus far to my knowledge. I have been able to solve the sudden visibility changes with FSUIPC and ActiveSky, but I would request that haze be made available at visibility settings greater than 60 miles in FSX. I have FS9 visibility maxxed at 59 miles and have never used a higher figure due to horizon haze disappearing at settings 60 miles or higher causing an unrealistic look in my opinion. What are the chances of haze being drawn farther in FSX ?

[michal 44]

>I have been able to solve the sudden>visibility changes with FSUIPC and ActiveSky,If this is the case quite a few people on ActiveSky forum would like to hear from you. I have been following this forum closely and to my knowlwedge no one successfully conquered this problem without seriously compromising other parameters. I know of a "fix" but it requires some comromises with max. visibility at high altitudes. Even Damian Clark, creator of AVS doesn't know the solution - I bet he would love to hear from you too.Michael J.http://www.precisionmanuals.com/images/forum/pmdg_744F.jpghttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg

[Guest Fjorko]

There is NO fix to this...it's a limitation to FS9... something needs to be done to the core weather engine and as tdragger has mentioned it has something to do with hardware fogging ( whatever that means )

[Guest thefringe]

Exaxctly. I have 'solved' the problem by keeping max vis at 59 miles. This is why I am requesting the distance be increased in FSX.

[michal 44]

>Exaxctly. I have 'solved' the problem by keeping max vis at>59 miles.Tell me how you solved the problem with "59" miles. I can only "solve" it with 29.Michael J.http://www.precisionmanuals.com/images/forum/pmdg_744F.jpghttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg