Continuing visibility hassles

[brucewtb 247]

Why is it with the following metar;YSCM 120300Z 33016KT CAVOK 27/07 Q1018 FM0300 MOD TURB BLW 5000FT RMK YSCM 112246Z 0024 36022G38KT CAVOK FM15 29010KT CAVOK FM20 34012KT 9999 -RA BKN120 FM00 MOD TURB BLW 5000FT TILL 15 RMK AUTO GENERATED AS2004.5with visibility set to a minimum of 30 sm and a maximum of 59 sm I am getting a sharp visibilty change at 2000 feet as displayed in the attached jpegs - AS2004.ini also attached.

[Damian Clark 1,127]

Hi Bruce,Using 146 test build (http://www.hifisim.com/AS20045-b146.zip) I am unable to duplicate any such behavior. I can't tell from the screenshots, but you may have entered a thin cloud layer which is possible when CAVOK cloud generation is not disabled. If a stratus cloud layer was placed, it will reduce vis when inside the boundaries. If no cloud, then something strange is amiss... please try B146 and if it continues please give me procedures, wx file, ini and flightplan and I'll try to duplicate.Thanks!

[brucewtb 247]

Thanks for you comments.As I recall CAVOK clouds was disabled, but you can check the ini file. Got the same thing with B145. I then disabled FSHaze - same thing, the disabled vis smoothing - same thing. Will try B146 and report back but as I am away from home at the moment it will be a week or so.It may have nothing to do with it, but I get the impression that you tend to get these visibility anomlies when CAVOK is in the metarBruce

[brucewtb 247]

Hi againWell after a couple of weeks and a new AMD3400 system I am back in the air with AS2004 B147 but I get the same visibility anomalies as described above - a marked drop in visibilty at about 2000 ft AGL. Default settings except min visbilty set to 30 nm and CAVOK clouds disabled. Metar as below:YSCM 290800Z 07013KT CAVOK 14/04 Q1024 RMK AUTOGEN AS2004.5YSCM 290424Z 290606 18015KT 9999 -SHRA SCT030 FM12 14010KT 9999 SCT035 FM01 06013KT 9999 FEW040 RMK AUTO GENERATED AS2004.5Bruce

[JSkorna 137]

Hi,I would like to see all your AS settings. Please post your latest AS2004.ini and I'll take a look!Hope this helps,JimActiveSky Supporthttp://www.hifisim.com/images/as2004proudsupporter.jpg

[brucewtb 247]

Latest AS ini file attached, on closer inspection this vis change occurs closer to 1900 feet and comes and goes as you climb and descend through this level. Most noticeable, and perhaps only happens, when vis in metar is CAVOK or 9999; eg effect NOT reproduceable at KSEA with following MetarKSEA 300056Z 20010KT 10SM BKN049 BKN120 OVC200 11/07 A3009 RMK AO2 KSEA 292327Z 300024 21011KT P6SM SCT035 BKN060 OVC200 TEMPO 0002 -RA FM0200 19013G20KT P6SM BKN045 OVC060 TEMPO 0204 -RA FM0400 19015G25KT but happens back at my hometown of Merimbula on th SE Australian coast with the following metar YSCM 300100Z 08009KT 9999 SCT040 15/05 Q1026 RMK AUTOGEN AS2004.5YSCM 292255Z 300024 17006KT CAVOK FM12 36015KT CAVOK FM21 36020G32KT CAVOK RMK AUTO GENERATED AS2004.5 RMK AUTO GENERATED AS2004.5 RMK AUTOBruce

[JSkorna 137]

Hi Bruce,I would like you to make the following changes and see what happens:MimimumVisibility = ZeroDepictFS9HazeLayer = FalseFogGeneration = FalsePlease let us know!Hope this helps,JimActiveSky Supporthttp://www.hifisim.com/images/as2004proudsupporter.jpg

[Damian Clark 1,127]

Hi,I still cannot reproduce any such effect. I will attempt some further FS9/FSUIPC/AS option tests to see if I can come up with anything... Thanks for your patience and feedback Bruce...

[brucewtb 247]

JimI made those changes and the anomaly still occurs. Screenshots attached.MetarYSCM 310200Z 33014G26KT CAVOK 21/08 Q1020 RMK AUTOGEN AS2004.5YSCM 310028Z 0220 06012KT 9999 FEW040 FM11 VRB05KT 9999 SCT040 PROB30 1820 0800 FG T 23 25 20 16 Q 1021 1019 1020 1021 RMK AUTO GENERATED AS2004.5 RMK AUTO GENERATED AS2004.5 RMK AUTO GENERATED AS2004.5Bruce

[brucewtb 247]

An update.I tried the tablefog suggestion made in the Graduated Visibilty thread but it made no difference. I assume the tablefog entry would, in my case, go in the NVIDIA on WinXP/2K section of display.cfg, anyhow this section had a line referring to my latest driver update so I guess it is the active part.RegardsBruce

[Damian Clark 1,127]

Hmmm..Bruce, please shoot me an email at damianc@hifisim.com... I have a test build to send you which may help us isolate where the problem is... Thanks!

[Guest 320MAD]

Hi Bruce,Listen the fix I used in the display.cfg is only used for the Radeon 9200 mate, it won't work on other cards.Chers320MAD

[brucewtb 247]

Well the problem is seemingly solved and the tablefog entry on display.cfg was the fix after all - so apparently it works for nvidia cards as well. Evidently when I made the change initially I didn't reboot the PC. But after a few days doing other things I came back to this issue and to my surprise the anomaly didn't occur. The only change had been this tablefog thing so I went back into display.cfg and commented out the entry, rebooted and sure enough the anomaly returned. I then re-enabled the tablefog entry, rebooted and the anomaly didn't occur.Thanks to Damian and others for their patience.Bruce

[Guest 320MAD]

Glad to hear your problem was solved. The post I found that fix from stated that it was only a fix for Radeon cards... Thanks for letting me know it works on Nvedia cards as well.320MAD