PMDG 737 NGX - landing and taxi lights don't illuminate ground at dusk

[sidfadc 1,344]

Hi Steve,

 

As requested from your PM, I would love to know the answer.

 

http://www.avsim.com/topic/481471-landingtaxi-lights-dont-illuminate-ground-at-dusk/

 

Cheers

[SteveFx 258]

Hi sorry yes I spotted your post because the fixer seemed to get unfairly blamed!

 

There are lots of ways of coding lights in FSX and the various techniques have their own strengths and weaknesses. 

 

Developers are constrained by what the core FSX engine can offer.

 

The default landing lights on e,g the Cessna use a single "day" texture which is blended with the ground using the alpha texture of the texture.   Therefore the landing light is displayed at full power when FSX starts showing landing lights which is a couple of mins before dusk starts.

 

So if you start with the Cessna 10 mins before dusk you will see the lights that you like have their own flaw - they suddenly appear just before dusk and are unrealistically  bright for the initial period.

 

The PMDG landing lights are I am sure a blended light with a black day texture and a bright night texture. For blended lights FSX starts the blend process about 10 mins into dusk (when you see the terminal lights come on in fact). 

 

I know this last fact only too well because it caught me out in the initial release of the fixer as I tested it day, night, dawn and dusk and never thought to sit for 20 mins watching the transitions.People then started reporting mirror like runways at some legacy airports as I hadn't fully understood the subtleties of how the blend worked.

 

At the start of the blend  process you go from 0% of the light  texture being added through to 100% at the end of the blend.  I assume that the end of the blend is the end of dusk but I haven't actually needed  to ever test that.

 

So the PMDG landing lights blend in smoothly but they only become really noticeable towards the end of the dusk period.  This is the light "shine" on the ground we are discussing not the light lens viewed from in front which always comes on.

 

So there isn't anything wrong its just  the way FSX is - the other lights aren't  really better they just have a slightly  different set of pros and cons.

 

If you look around in the FSX world and watch airport ground lighting you will see the different techniques play out.

 

Hope this helps. 

[sidfadc 1,344]

Thanks for the very detailed reply Steve!

 

So this means the issue affects everyone with the PMDG 737? According to Kyle in the PMDG forum the modelers couldnt reproduce it and I dont see many other people replying to my post saying they have the same issue. Kyle reckons my issue is unique to me.

 

My A2A comanche displays the light on the ground just fine so is it just the way each developer models their own system?

[SteveFx 258]

It will be the same in every FSX system  (except for monitor calibration, eyesight etc) assuming the standard lights are used.

 

But there is nothing wrong or anyone being "affected"  the PMDG lights fade in gradually  starting 8-10 mins into dusk whereas the A2A lights start at full intensity right from the beginning of dusk.  

 

If you look from spot view and toggle the lights off and on its much more obvious that the PMDG lights are shining on the ground when faint than from the VC especially with a brightly lit terminal as contrast.

 

You prefer the A2A light style from the VC that is all - other people may well on balance prefer the PMDG style.

[sidfadc 1,344]

Thanks, I much prefer the A2A method because I can actually see the path to the runway at dusk!  I'm assuming there is no tweaking to be done to change the PMDG lights?

[sidfadc 1,344]

The plot thickens....today I have flown from Cuba (MUHA) to Miami and the landing lights were visible on the ground before and during dusk??  If I switch the airport to EGCC, same setup as my post above I don't see the lights before and during dusk.

 

I use UK2000 EGCC but MUHA is stock FSX.  Does this mean it be related the scenery I'm using at different airports, both payware and stock?

 

EDIT: Ok this is beginning to really irritate me now, I've just switched to Gatwick EGKK which is a stock airport and I don't see the landing lights before or during dusk so there goes my theory above!