Having problems with Visablity smoothing

[John EGPF]

Hi

I,m running fs2004, and I fly using Downloaded static weather.

I have enabled visabilty smoothing with the default setting, but I'm still gettings sudden changes of visability.

Visability would suddenly go from around 20 miles to unlimited, then a few seconds later the visabily would return to 20 miles.

I,vre also noticed this happening in relation to change in alltitude, say around 18000 feet ,the visablity will suddenly change as in the above example.

Does the smoothing work only with global weather, or should it work with downloaded static weather?.

Many thanks

John

[Pete Dowson]

I have enabled visabilty smoothing with the default setting, but I'm still gettings sudden changes of visability.

Visability would suddenly go from around 20 miles to unlimited, then a few seconds later the visabily would return to 20 miles.

That sounds like cloud layers. I cannot, and would not even try to interfere with those. This sudden appearance of clouds at the aircraft has hapened in previous versions of FS, and it certainly also happens in FS2004.

Does the smoothing work only with global weather, or should it work with downloaded static weather?.

In the recent versions of FSUIPC, it works universally, with all weathers. But it is only the visibility. Clouds suddenly appearing or disappearing are totally different. I am not getting involved in that mess. Sorry.

Regards,

Pete

[John EGPF]

Hi Pete

Thanks for the reply.

My problem is not with the sudden appearence of clouds, I find the way the clouds form in fs2004 a huge improvement from fs2002.

The instant visibilty changes are happening even in clear skies.

Many thanks

John

[Pete Dowson]

The instant visibilty changes are happening even in clear skies.

Yes, I have seen this too, but I am pretty sure that this is some cloud phenomenon, even so. At least every example I've seen has been, so far.

One way to check. Go to FSUIPC's Logging page and enter the offset "0E78" in the first entry, with a type of "U16". At the bottom select "AdvDisplay". This makes FSUIPC continuously show the value in 0E78 in the FS text display bar on screen. It is this value which FSUIPC uses to manipulate the visibility. The units are hundredths of a statute mile.

When it happens, see if the value so displayed is low, matching the apparent visibility. If it is then I'll need to know how to reproduce this so I can deal with it. If it isn't, then what you are seeing is certainly related to cloud formation. As I say, every case I've come across has been down to the latter.

Check whether you have the weather dynamics enabled (the slider for changes in the weather menu). If that isn't set to the very left, then you are quite likely to get cloud formation, and it can happen at the aircraft location. I think this is what is happening.

Let me know, please,

Regards,

Pete

[John EGPF]

Thanks for the suggestion Pete will try it out.

I have tried with dynamic slider enabled and also at none, no difference with regard to the visabilty changes.

Noticed something odd just now in a flight, flying at 33.000 feet I looked straight down and noticed what seemed to be a thin layer of lower visabilty which is flying along with my aircraft!.

This is not related to FSUIPC though I noticed this before i even installed it.

Just wondering is it best to fly with dynamic slider switched off when using static real weather?.

cheers

John

[Guest Anonymous]

Unless you are running at maximum cloud density, your skies are not `clear` even though they appear `clear`. If there is a cloud layer, and the cloud textures themselves are prevented from rendering by the applied limit in the sim menu, then you can see this visibility layer coming and going as the aircraft rises and falls through what should be a cl9oud layer. I think the sim uses a form of Pete's visibility limit settings within the sim and automatically reduces the visibility in cloud. Either that or the METAR data is incomplete.

If you use the visibility parameters in FSUIPC yo can overcome this difficulty as it ensures consistent visiblity and graduated change if and when you emerge from it.

[Pete Dowson]

Noticed something odd just now in a flight, flying at 33.000 feet I looked straight down and noticed what seemed to be a thin layer of lower visabilty which is flying along with my aircraft!.

That's a thin cloud graphic deliberately laid on the top of the visibility layer (at the upper altitude for this as seen in the Weather dialogues). It was added by MS in response to copmaints with FS2002/2000 that after climbing up out of the fog when looking down the view is perfectly clear, when obviously you should see the haze/fog below, masking or at least fogging the ground somewhat.

I assume that since visibility is a video card fogging mechanism, this apparently couldn't simply be applied only to the ground textures, so instead they added this cloud graphic. However, being effectively a cloud, it is only drawn to the distance set by the cloud "view distance" slider (one of the sliders in the Options-Settings-Display-Weather dialogue). For best results, set all the sliders in there to maximum, but beware of lower frame rates then.

Just wondering is it best to fly with dynamic slider switched off when using static real weather?.

That's a personal choice. Depends whether you want more varied weather I suppose.

Regards,

Pete

[John EGPF]

Simon

Thanks for the help but i,m running at max cloud density.

Pete

I Tried your advise on logging visibilty, and the numbers match the visibility changes.

Descending from 15000 feet the number on screen was 4000.

approaching the airport and descending the numbers start rising slowly matching the view out the windshield.

the change is gradual untill it goes from 5800 to 6000 when the visual change is abrupt.

I will try changing the visabilty limits in regard to clear, cloudy, raining.etc

Ms weather seems to be programming mixed with a little black art :)

thanks again

John

[Pete Dowson]

Descending from 15000 feet the number on screen was 4000.

approaching the airport and descending the numbers start rising slowly matching the view out the windshield. the change is gradual untill it goes from 5800 to 6000 when the visual change is abrupt.

Your visibility increases as you descend, not decreases? You've not got graduated visibility enabled, then? It should be the other way around. I cannot imagine why you'd want more visiiblity at lower altitudes than higher?

When you say "it goes from 5800 to 6000 when the visual change is abrupt", abrupt to what? The difference between 58 miles and 60 miles is not going to be a very visible change, that's a pretty small increase (less than 3%). So if you saw "an abrupt" change of some sort (which way?), and there was no abrupt change in that value, it was definitely forming or dissipating cloud, as I said.

Regards,

Pete

[John EGPF]

I dont want it pete but thats what fs2004 gave me :)

Graduated visabilty is set to 35000 @ 60 miles.

Guess Germany had really clear weather at ground level :)

Problem must be some "invisable" cloud layer as you mentioned

all the best

John

[Pete Dowson]

I dont want it pete but thats what fs2004 gave me :)

Graduated visabilty is set to 35000 @ 60 miles.

Guess Germany had really clear weather at ground level :)

Ah, so you didn't set any maximum at ground level for the graduated visibility to start from? It seems daft restricting visibilty to 60 miles at 35,000 yet letting it be completely unlimited at the surface. If you want to get the best from the facility, all the four values in the "maximum" settings should be LESS than your topmost level visibility, else you will get such an odd topsy-turvy effect.

Regards,

Pete

[John EGPF]

"all the four values in the "maximum" settings should be LESS than your topmost level visibility, else you will get such an odd topsy-turvy effect".

Thats the way I did it in fs2002

I didn't set surface levels as I though the weather system in fs2004 would give me appropriate visibility levels at low level, which would be more realistic.

Does leaving the maximums settings unchecked give my unlimited visibilty at lower levels, regardless of what the MS weather thinks it should be?

all the best

John

[Pete Dowson]

[quote name="John EGPF

Does leaving the maximums settings unchecked give my unlimited visibilty at lower levels' date=' regardless of what the MS weather thinks it should be?[/quote]

No. You get whatever the MS weather says. But if the METAR is "CAVOK" then you'll get the maximum FS visibility, which really in not very realistic for the UK, and is going to be greater than your 60 miles upper visibility for graduation. If you don't want the odd upside down effect, then the maximum values need to be less than or equal to the maximum upper level visibility, do you see?

Imposing maxima of 60, 50, 40 or whatever at surface level won't destroy the realism from the METAR reports, as they don't give such high visibility values in any case. I find the default maxima quite suitable for UK flying, or possibly a little lower than those -- maybe 30 miles in clear skies, down to 10 when it's overcast and raining.

Regards,

Pete

[John EGPF]

Hi Pete

Thanks for info regarding Cavok very informative.

I,ve got it at 20 miles clear down to 10 for rain, what difference it makes.

You get the best of both worlds, the scenery looks 100% better with reduced visibility at low levels but clears just enough at high alttitude to give you a good view while still being very atmospheric.

Before using FSUIPC in nearly all flights I would reach 18000,19000 feet and bang, the visibility went to unlimited, that was my reason for getting FSUIPC.

And its fixed that and a whole lot more, great stuff

Cheers

John