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Problem with clouds in marginal ILS conditions


bobwallison
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Hi everyone.  First post on this forum.

I bought SMP last week and have been very impressed by what I have seen so far.  I run it with RWC and Active Sky XP, although I have also run it by itself, with weather conditions input via the weather screen in XP11, in manual mode.

My problem is with cloud thickness and ceiling heights, which often seem to be a poor match for the Metar report and what shows up in the XP11 weather settings screen.  I have been scudding along the top of solid cloud at 6000ft when XP11 was set to 3500ft tops (no RWC or ASXP in that instance).  Then with overcast cloud base set at 1000ft AGL, I have descended through 600ft AGL before seeing the ground.  More usually, with ASXP, RWC and SMP running together, it is the opposite problem and I can see the ground through overcast cloud while I'm more than 2000ft above the supposed cloud base.  (Log file attached for this last case.) 

Is this still a known issue and are there any solutions or work-arounds?  I know this has been discussed before but the software has moved on, and some of the suggestions are no longer valid for my version (SMP 4.9.6 and RWC 1.1).

On a related subject, I sometimes set up custom weather areas in ASXP to give me exactly the weather I want for departure, en-route and arrival.  Will they work as intended with RWC and SMP?

Main message here is that I like the software, but I will like it a little more if I can practice ILS approaches in marginal conditions that match the metar.

Log.txt

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I think what you are seeing is our representation of "scud" - there is an area above and below the stated cloud altitudes for overcast clouds where the effect fades in and out.

You might try changing your overcast representation setting to see if you can get results closer to what you want. "Solid procedural" and "broken procedural" have this scud effect, but the other choices do not.

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Thanks for the quick response @sundog.  So the problem isn't down to scud, because I use turbulent HD for overcast clouds (procedural textures look like a sheet of white card, sadly).

I have tried again with cloudbase at 400ft AGL and >=10km visibility below the cloud.  What I get is the ground under the plane's nose clearly visible at more than 1100ft AGL but visibility ahead limited to 2 miles or so by cloud/fog - the exact opposite of the metar report.  As I descend on the glidepath, the fog ahead clears but in very noticeable steps rather than gradually.  (Log of this different situation attached.)

This isn't a complaint - I'm aware that X-Plane's weather rendering is flawed - I just want to be confident that I have set up SMP to best advantage.

Log.txt

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If you're using "turbulent HD," then SkyMaxx Pro isn't actually controlling the fog at all. You're seeing X-Plane's built in fog effects there.

However, another part of the issue is that there is some debate over whether the "cloud base" should represent the lowest altitude at which any cloud puffs from the layer appear, or the altitude at which the cloud becomes fully opaque as you fly through it. There can be a difference of several hundred meters between the two.

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Fair point about variable cloud bases - I'm now happy on that score.  But I still have a problem with the fog/cloud on the ground and I'm sure it isn't X-Plane's built in fog effect. 

Here's an image using ASXP without SMP and RWC, visibility below the cloud is >9999m, as per Metar:-

80368185_DefaultXP11.thumb.png.95be7f857ccad80492b7d7e66a0cc0c4.png

 

And here's the same approach with SMP and RWC enabled, using ASXP's historical weather function to give exactly the same weather. Visibility is about 2000m - not as per Metar, and the solid wall of cloud/fog looks very unconvincing:-

127433810_WithSMPandRWC.thumb.png.13491175b9675d7f7c50284043dd318b.png

 

It's as though there was a bank of cloud right down to ground level which constantly shifts as the plane moves - here's the view a minute or so later after the plane has come to a halt at the end of the runway.  I'm not in the cloud here - it is still some way ahead.1393489994_HaltedSMPandRWC.thumb.png.35ac181570a2fc619a06da5108c9846c.png

Please can you advise if there is a work-around or fix for the wall of cloud?  Or perhaps recommend some settings to mitigate it? And the other question from my first e-mail - do SMP and RWC play nicely with custom weather areas in ASXP?

Regards.

Log.txt

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I do remember testing out custom weather areas when we were testing ASXP integration; as long as you have a recent version of ASXP it should work.

Honest to god though, if you're not using the solid or broken procedural overcast settings in SkyMaxx Pro, we do not render fog effects at all. I'm really puzzled at what you're seeing there. It's hard to tell from your screenshot if that is really a fog effect or just looking at the particles that make up a cloud from the inside - but it looks like fog to me. If I'm wrong though, it could just be that the cloud really is on the ground and we've pushed it down because we think the METAR is indicating fog. Would you have the actual METAR code used for that scene? It would be helpful to have something concrete to dig into.

 

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That's good news about ASXP's custom weather mode - thanks for that.

As for the other issue, I have re-run the situation at the same time and place so I can attach a completely consistent set of data and pictures.  I also recorded a video using XP11's tool - the pixellation is shocking and it's still about 180MB for a minute or so of video - so I'll only post that if you ask for it.  It does show the cloud bank receding as I fly towards it.

I also restarted XP11 with just SMP running (no ASXP or RWC) and fed the same weather in manually using XP11's weather settings - same results.  Also with visibility 40sm and cloud base 900ft above the runway - similar results.  Perhaps I am seeing cloud puffs below the set base, although I don't know why they seem to move as the plane moves.

I use Ortho Scenery and have enhanced runway environment - but they are just better bitmaps I think, I cannot see them interfering with cloud rendering.

Thank you for your continued interest in this - hopefully you will make more sense of it than I can.

Regards,

Bob

Screenshot (54).png

1968512622_Screenshot(55).png

Screenshot (56).png

Log.txt METAR.rwx

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Thanks, the metar.rwx allowed me to understand what you're seeing.

So this does come down to the cloud base height being lower than the size of a single cloud puff, resulting in the puffs intersecting the terrain.

"Solid procedural" for overcast would allow for more precise positioning. The problem is you're reporting that it looks like a "white card", when for this scene it should look like the attached image.

Perhaps a screenshot of your X-Plane graphics settings would help me understand why it's not looking as it should be. (Or, it may just be that there was a bug I've fixed locally since 4.9.6 was released that I forgot about fixing!)

 

941399234_F-4-2020-11-1316_32_11.png

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