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Ray Proudfoot

No amateur astronomers on the ACES team then!

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I was really hopeful that FSX would finally resolve a really old problem. That of stars showing whilst the sun is above the horizon. The only bright objects visible at sunset are the moon and Venus. You won't see any stars until 20-30 mins later and even then only in the tropics where twilight is very short.Sadly it couldn't be done or perhaps wouldn't be done. It's a shame really because in many other respects the skies look so much more realistic than in FS9.I'd really like to hear from someone on the ACES team as to whether this inaccuracy was discussed.I live in hope that before I pop my clogs there will be a version of FS that addresses this anomaly.

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Yes it is rather unrealistic (maybe it can be changed somehow ?). It would be nice to have the brighter stars show first too but I find the apparent brightness difference amongst stars of various magnitudes isn't well depicted (perhaps also a limitation of me having an LCD monitor at 1024x768) so that stars like Vega, Sirius, Arcturus, Antares etc don't have the same impact as in real life.I also find the moon is not very good in FSX... I must find a new moon replacement.

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It might not fix this particular problem, but look for "autostarx.zip" in the AVSIM file library.File Description:AutoStar is a program that allows new features to be added to the night sky. It adds the brighter planets in the correct position for any date. Optionally it can add comets, images or user objects such as a lunar eclipse or Messier objects. The program can import the SAO star catalogue, thus allowing the number of background stars to be significantly increased. Filename: autostarx.zip License: Freeware Added: 18th December 2006 Downloads: 4471 Author: Chris Wright Size: 714kb

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Hi,The definitions of the various stages of darkness are very well described in this Wiki article on Twilight. http://en.wikipedia.org/wiki/TwilightGiven that MS have programmed the sunrise and sunset times for the entire planet it shouldn't be difficult to show stars and planets of various magnitude when certain times have been reached.For example, Venus and Jupiter could become visible at Civil Twilight; stars down to magnitude 2 could become visible when Nautical Twilight is reached and the remaining stars when Astronomical Twilight is reached.All these points can be derived from the time of sunset so it seems a pretty simple change to make. Obviously the reverse would need to happen before sunrise.Although it might seem a bit picky given the realism of the scenery it's small things like this that can make or break the illusion of realism.I know the ACES team read thse pages so how about a comment please chaps?I agree that LCDs aren't as good as CRTs in displaying different brightnesses. But at least they are sharper :-)Cheers,

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Hi Chris,Although you're correct in saying it won't resolve this problem that offering sounds really good. Nice to see it's had over 4000 downloads.Thanks.

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In terms of correctly showing brighter stars, FSX represents a *huge* advance over FS9. In FS9 the total brightness dynamic range was limited to just 3:1. In FSX, stars are shown with full 24 bit colour which means, for a white star, the dynamic range is now 256:1, an enormous improvement. However, the default brightness assignments still have a small dynamic range.My AutoStar program addresses this (thanks for the plug, dswo!) First, when creating a new star set the dynamic range can be specified so you can choose how much brighter bright stars will appear. In addition, brighter stars will be created from a small group of up to 16 stars, thus effectively multiplying the dynamic range by 16. The default star set provided with the program has a larger dynamic range than the default, and also slightly stronger colours. But you can play around with the brightness and dynamic range settings to get the balance you want.By choosing a low brightness and high dynamic range setting, only the brighter stars would appear, which might be appropriate for early dusk. A zero brightness setting should mean that no stars show at all, which would be correct if the sun is still above the horizon. I've noticed that in several games the stars appear together with the sun, which is not very realistic!Finally, you can use the user objects feature to place your own image of the moon in the sky.Of course, another option would be to replace the default bitmaps with improved ones.There is one feature I might get around to adding: to reduce the number of stars close to the horizon.Best regards, Chris

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Now we need to stopped the stars showing in front of the moon !! Only noticed it the other day.

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Hi, all.Im not in familiar waters here.. But my guess is stars in FSX is treated like an effect or a certain *.bgl file triggered by time and/or season. It would help a lot if stars did not show until the "Time of day" or season was "Night". To do this you need to change som variables within the FSX code. :-sun1

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Hi Chris,I've downloaded but not yet installed your program. Thanks for creating it.If different brightness and dynamic range values can make stars appear or disappear then if the program ran as a dll within FSX it might be possible to control how bright they appear depending on the time.I appreciate this is easier said than done but if it could be achieved then the problem of stars beng visible with the sun above the horizon could be eliminated.Cheers,

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Hi Scandi,The stars are contained in a file named stars.dat, not a BGL.As Chris has said by changing their brightness and dynamic range they can be made to appear or disappear.Ultimately it would need a change of the source code but workarounds are always possible. You just need the knowledge and desire.

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Ray, AutoStar works by writing a new version of stars.dat. As FSX loads this file on startup it probably isn't possible to change the stars without exiting FSX.However, I'm not very familiar with the inner workings of FSX, but I wonder if anyone knows whether there might be FSX system calls that tell it to reload specific data? If so, then something might be done, in fact it would open up some interesting possibilities....I just looked over the program. If you want to play with the brightness and dynamic range settings, then it is necessary to import the SAO star catalog. It's pretty easy and there are full instructions in the manual. To summarise: 1. Download the catalog file and for simplicity rename it to SAO.dat (the address is given in the manual). 2. Decide the limiting magnitude (e.g. 7.0) and import the file (input file would be SAO.dat and output file could be SAO70.dat). You probably won't need to run this again. 3. Now you'll run CONVERT STARS. Set Source file to SAO70.dat. 1 and 300 are good values for Colour strength and Brightness settings. Exponent sets the dynamic range and can have values ranging from zero to 2.5. Zero will create stars all with the same brightness - not very useful. 2.5 will give a 'natural' dynamic range i.e. pixel brightness corresponds to the actual magnitude. However, displays will probably not cope with this (faint stars would probably be so faint as to be invisible). The default value is 1.5. By increasing this (e.g. 2.8) you will increase the dynamic range. 4. Finally click on Make stars! to create the stars.dat file and run FSX. If you enable Show circles you should see the celestial circles in FSX. This is a good test as it covers the entire sky.Have fun and let me know if any problems/questions.Best regards, Chris

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just wanted to jump in and thank you Chris for your work, the autostar program is great! Have not had a chance to try the FSX version yet but I still enjoy your FS9 version! Your work is much appreciated

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Alex, thanks for those kind words. You'll find the FSX version is a big improvement with many new features. For example, as FSX displays stars in full 24 bit colour, images such as comets are now fully photorealistic.Best regards, ChrisP.S. it's available in the Avsim library, but it's also available here: http://www.kline.demon.co.uk/AutoStarX.zip I'm pretty sure it's the same version as in the library.

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Hi Chris,Thanks for the background and suggested settings. I'll install the program over the weekend and come back with my comments.Cheers,

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. . just to add a little flavour, Ray - to that of stars showing whilst the sun is above the horizon - back in 1963 on a ferry ride in a Folland Gnat at or somewhere above 44,000 ft. with tops at about 8000 - midday - I was utterly amazed to see a dark blue sky with stars quite visible directly above, the sky fading progressively lighter down toward the horizon. I hadn't ever been that high before. That day I also learned why canopies are covered with soft cotton cloth!Regards,

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Hi Paul,That sounds spectacular! I've not been that high myself but do remember how dark the skies went during the total solar eclipse I witnessed in 1973 in a ship off the coast of Mauretania.Some stars were visible in a sky as dark as one about 15-20 minutes after sunset but my main attention of course was on the totally eclipsed sun.Having seen photographs taken by passengers on Concorde the sky is nearly black at FL530 and higher. FSX is getting better in that respect but still some way short of total realism.Cheers,

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for sure, Ray, but my enjoyment for FSX is certainly increasing daily, though. With the right hardware, and the addons NOW beginning to show - it's becoming a much better sim than FS9. We need some big iron aircraft to replace the default ones, but they will come! This month I have bought the Eaglesoft Citation II, ASX, UTX and Aersoft's Aspen, so she's becoming more real by the day!:-beerchug

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Hi Paul,I'm dipping my toe cautiously into the FSX pond too. My main PC isn't really fast enough to run it realistically but at least it's flyable which it certainly wasn't pre-SP1.As I have Project Magenta software I'm not reliant on panels and have copied the PMDG737 to FSX with pretty good results. I just need PSS to modify Concorde.I too have ASX and the skies do look very good providing I don't fly around sunset. I seem to have turned full circle :-)Cheers,

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Ray, my friend - you need some more ram. It will make the world of difference! A P4@3gig ought to be good, and the 1950 is excellent! but XP and FSX combined will gobble up 1.3 - 1.5 gig on a two-gig system. This means you're swapping - and not with swimsuit models, either! :-lol

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Hi Paul,Confucius say "more RAM does not make for better frame rates" ;-)Yes, it would make things smoother and load times would undoubtedly decrease but I wouldn't get higher frame rates. My P4 is 2.5 years old and I bought the X1950 to get another year out of it but it's not as fast as your XTX.Even in FS9 with addon airports such as FlyTampa and 100% UT Ai aircraft frame rates do struggle to get above low teens. I'll wait until the successor to the E6700 comes out and then reevaluate things.Fat chance of your final suggestion ;-)

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Hi Paul,The second shot looks great for dusk flying but once it went fully dark would the number of stars match or exceed those in the first shot?Ideally I would love to see the Milky Way once it's fully dark. Would that be possible without making adjustments to the star brightness and dynamic range using your program?Cheers,

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Ray, unfortunately not. I don't know if it's possible to change the star data while FSX is running. It's probably impossible. The only way would be to save the flight, exit and run AutoStar, run FSX and reload the flight. You can save the settings in AutoStar, so you could save settings as e.g. 'early dusk', 'late dusk' and 'night'. If you used the FSX demo you'll recall that the Milky Way was pretty bright. I was disappointed to see that in the retail it was so dark as to be virtually invisible (some people had complained that it was too bright in the demo). I've noticed that SP1 has brightened it a bit so it is visible now, although darker than the demo. By the way, changing the stars with AutoStar should make no difference to the Milky Way.Best regards, Chris

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Ray,You may want to check out the thread by Bill Learning that was recently dug out of the archives for some reason. 2 GB might really help you. If you are swapping, it will decrease stuttering and increase frames to a degree (though the 512 MB vid card should be mitigating things).I was much happier when I upgraded my laptop to 2GB. FSX ran on it before, but was a major pain. I felt much "lighter" when I upgraded and much easier to run.Though I must say that my AMD 2500 OC@3200/1 GB/128 MB ATI 9800 pro runs FSX quite well with scenery sliders rather high, though I need to keep air traffic off. I don't use that machine much at the moment. But if I do start to, I'll probably look into getting another GB for it. I think we're only talking $50 for it.BTW, I'm very intrigued by the thought of dynamically controlling star brightness. Wonder if it's possible.I must say, however, I'm not really fond of FS at night, however. The glowing lakes and ground REALLY annoy me.Thomas[a href=http://www.flyingscool.com] http://www.flyingscool.com/images/Signature.jpg [/a]I like using VC's :-)N15802 KASH '73 Piper Cherokee Challenger 180

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