AVSIM Commercial Scenery Review

Real Sky Pro

FSX and FS9

Product Information
Publisher: Sandon Lyon
Description:  A look at both the FSX and improved FS9 versions of Real Sky Pro.

Download Size:
5.23 MB (Both versions in 1 file)

Simulation Type:
Reviewed by: Alan Bradbury AVSIM Staff Reviewer - September 13, 2007

Something close to every pilot’s heart…

They are always the keenest pupils, being the first on the aerodrome in the morning and the last to leave at night, and invariably fret about the mess on non-flying days, watching the sky from the windows at frequent intervals for a sign of the rain clearing up.” Ira Jones, King of Air Fighters.

That’s right, pilots are obsessed with the weather, and because talking about the weather is our national pastime, British pilots are even more obsessed with it! So, being a Brit and a pilot, it was with quite some interest that I set out to review Real Sky Pro – as it called to mind those critical glances up at the sky which every flyer makes before climbing in the cockpit.

About the product

Real Sky Pro is a nifty little utility which professes to add more realism to the sky textures in Microsoft’s Flight Simulator, without reducing frame rates, and in some cases, even threatening to increase them. Bold claims indeed, particularly in view of the fact that what one person considers realistic, might not be thought so by the next.

Hmmm, definitely some things to investigate here then, but before we start, I would urge you to keep in mind the subjective nature of opinions on what might be considered ‘realistic’ as you read this review and draw your own conclusions. Nevertheless, with my carefully pre-flighted weather eye, and British stiff upper lip, I shall try my best to be as bipartisan as possible.


Real Sky Pro, for both FSX and FS9 comes in a downloadable zip file, subsequently unzipping into two self-installing .exe files, one for each version of Flight Simulator. A single registration code unlocks both of them. This makes it two utilities for the price of one, or, if you are a cynic with only one version of FS, one utility which costs twice as much as it needs to. However, since Real Sky Pro is not particularly expensive at 26 Dollars, I think you would have to be very cynical indeed to view it that way!

When installed, Real Sky Pro sits on your hard drive taking up 28.6Mb for the FS9 version and 25Mb when in FSX flavor, so it is apparent that there are some differences between the two, and in what they offer. Installation in both FS9 and FSX was faultless incidentally, although RSP’s FS9 help page cautions users about altered registry files possibly having an adverse effect on the program working as expected. Specifically, it points out that registry changes made by FSX, and occasionally by some other add-ons too, might make the utility malfunction when installing for FS9.

As it turned out, I had both FSX and FS9 on the same C drive of the computer I used to test Real Sky Pro, and encountered no problems. This despite the fact that I have plenty of registry-altering add-ons, such as scenery, co-pilot utilities and complex extra payware aircraft in both installations. So perhaps this registry issue warning is more in the nature of a catch all than a certainty, nevertheless, be aware of it as a possible source, just in case you do have any problems.


Documentation is what might be fairly described as ‘sparse’ for Real Sky Pro. Sparse in this case meaning there isn’t any sort of manual at all! Initially this surprised and concerned me, but I have to admit that since Real Sky Pro ‘does what it says on the tin’, this would only seem to present a problem if you run into difficulties. Unfortunately, running into difficulties is exactly the kind of circumstance in which people need to turn to a manual!

So, RSP does make somewhat drastic alterations to your FS installation itself, and evidently may suffer from difficulties with registry changes made by FSX and add-ons too. With this in mind, I think including some suggestions as to corrective action in the event of difficulties with Real Sky Pro, other than the blanket ‘reinstall FS’ advice which is offered, might not have gone amiss. Re-installing FS is not a five-minute job for most people nor something they look forward to, and many FS users are not experts on manually making registry changes if this remedy does not appeal.

Admittedly, unusual registry changes and the necessity to correct them are not the fault of Real Sky Pro, but any specific data its developer has on this issue might have usefully been mentioned in a ‘Read Me’ file. I personally would like to see something of this nature added to the RSP installation folder, as it could certainly do no harm and might actually avoid the necessity for that dreaded re-install, should some users have problems.

As noted, the program does feature a ‘help’ page, but this is not hugely informative. Although on the plus side, it does include the developer’s contact email address. And happily, I found Real Sky Pro’s developer, Sandon Lyon, extremely helpful and quick to respond to my questions too, which is always an encouraging sign. The value of prompt and informative support direct from the programmer is not to be underestimated, so it’s not all bad news in the unlikely event that you might need assistance.

One other very important point to bear in mind however, is the help page on the FS9 version advises users that Real Sky Pro does not make back-ups of the textures it replaces, which means manually backing up your FS texture folder is a prudent thing to do. The FSX version’s help page fails to mention this. Considering that some FSX users who are new to flight simulators might not actually have FS9, and will therefore not install the FS9 part of this package, they’ll miss out on this warning.

At the very least, this needs addressing in order to warn of the ‘irreversible’ nature of the RSP process. Pointing out to inexperienced Flight Simulator users the location of the textures folder which they should make a back up copy of first before using Real Sky Pro, would therefore be a helpful gesture at an early stage.

User friendly?

The help page in the FS9 version advises us that Real Sky Pro is ‘user friendly’. And it certainly is in terms of how simple it makes the job of replacing default textures with the new ones it offers. But without a way to undo these changes, other than manually copying and pasting your back up texture files into FS - you did make a back up right? – there is no easy way back to the land of default.

This is not the end of the world if you do have a back-up copy somewhere, but it is not my, nor I imagine anybody else’s, idea of user friendliness. Automating the back up of the default FS files and adding an option to revert to them would certainly improve matters. I should point out that many other texture replacement utilities for FS are equally guilty of this, but that is not an excuse to follow suit.

Incidentally, when asking Real Sky Pro’s developer some questions for this review, I pointed out the FS9/FSX help page discrepancy, and given the helpful nature of his approach to my queries, I’d say it is a fair bet that this will be changed now that I’ve mentioned it. But as it stands, be aware of this and don’t say I didn’t warn you!

So, the lack of documentation and the minimalist help page could certainly do with improvement, but if all is going well (as seems likely), they should otherwise prove unnecessary.

This is all the documentation you get: the screenshots show the somewhat ambitiously named ‘help’ screen for FS9 and FSX. Thankfully, the utility seems to run without problems, and using it is not exactly rocket science, but notice there is no warning about the need to back up your originals in the FSX variant.

Every cloud has a silver lining…

Minor misgivings in the ability to revert textures and the somewhat frugal installation help aside, it has to be said Real Sky Pro is very quick and easy to use, and it does seem to work flawlessly once installed. Double click on the desktop icon, and it opens up – very swiftly I might add – to reveal a simple interface which makes it readily apparent of what is going to take place.

So in essence, Real Sky Pro is no more complicated than a set of replacement textures coupled to a graphical user interface to make previewing, selecting and installing them easier. It’s true the interface isn’t going to win any beauty contests, but it is very businesslike, and it does the job asked of it.

Looking at the big sky

Simplicity of operation notwithstanding, if you like lots of options in terms of how your FS skies look, you are most certainly not going to be disappointed with Real Sky Pro. But keep in mind that many of the texture changes are subtle, so if you are expecting to see radically different alterations with every choice you make, you might be surprised.

There are so many choices available in Real Sky Pro, I was half-expecting to see an option for a Martian sky, but while RSP stops short of offering that, it doesn’t skimp on any sky options for our own planet. In fact, the breadth of choice borders on being overwhelming, so it is nice to see selections offered in logical groups and sub-groups, arranged in such ways as: ‘Golden Dawn’ within the ‘Dawn 2’ textures collection. This makes finding what you want and installing it about as easy as it could possibly be. And it certainly helped me in keeping track of all the screenshots I had to take for this review!

All replacement textures are accompanied by a representative thumbnail panorama of a large section of the horizon, giving you a good idea of how they will look in FS. To install the one you fancy, simply click on the button alongside its thumbnail, then confirm that’s what you want and it’s done. Nice touch by the way, as it reduces the possibility of accidentally installing something with a clumsy mouse click whilst browsing. Note that installing most of these replacement textures requires a restart of FS to see them kick in, but the need to restart Flight Simulator is only really tedious if you happen to be doing a review of the thing and need to test them all! This individual approach to installing textures, I think, is infinitely preferable to making sweeping changes to all and sundry. So, a good job all round here.

The Real Sky Pro GUI couldn’t really be any simpler if it tried, which is good because it offers a vast array of textures that might otherwise prove bewildering. The odd typo crops up in the names of the textures on offer, and the GUI is no oil painting, but that doesn’t affect the quality of the textures themselves, so these are a minor quibbles.

One operational difference I did notice between the FS9 and FSX versions of Real Sky Pro, is that FSX refuses to initialize the 3D for a flight if RSP is still running, requiring you to alt+tab out and quit it before it will commence your flight. Not a major problem, but oddly enough FS9 doesn’t seem to mind at all if you leave RSP running.

What makes it any different from ‘the other one’?

Obviously, Real Sky Pro is not the only add-on for FS which can change the way things look in our virtual world, and while we are not exactly drowning in utilities of this nature, there are one or two competing for this market alongside RSP. The most obvious direct competitor, is Flight 1’s Flight Environment, which it has to be said, does offer more usability features than Real Sky Pro.

So how else do these two products differ?

Let battle commence…

Price-wise there’s not much in it. Although, RSP gets off to a good start here by being slightly cheaper than the Flight 1 offering and that may possibly sway some people, but I imagine not many will base their choice solely on a couple of bucks price difference. Especially for something that has the potential to affect every simulator flight they make.

Flight Environment pulls back level in the contest with RSP by having a prettier interface than Real Sky Pro, and more options to randomize things take it into the lead. The ability to save your favourites edges Flight Environment further ahead in the race too, and it looks like a sure-fire win. But just when you thought it was all over, Real Sky Pro catches up and then streaks over the FSX compatibility finish line, which is still not quite in sight for Flight Environment. And the crowd goes wild.

Therefore, if you want something to use in FS9 and FSX, right now (September 2007), Real Sky Pro is the only game in town, unless you are prepared to wait a short while for the Flight Environment update (which is on the way incidentally).

But that’s still not quite the whole story…

One other slightly subjective observation I would offer with regard to the difference between these two, is that I think Real Sky Pro concentrates more on pure realism in terms of what you are likely to see in the sky on a day-to-day basis. Whereas Flight Environment focuses on the ‘stunning eye candy’ approach that you also see in the real world, but probably less often.

The eye of the beholder and the eye of the storm…

This difference mirrors another hotly-debated scenic variance that has cropped up argumentatively in many online forums with regard to the two other add-ons; namely, the rival UK VFR terrain scenery sets from Horizon Simulations and Just Flight, where arguments about colour palettes have raged furiously. Sim users will probably be equally divided on which is the better choice with regard to Real Sky Pro and Flight Environment too, and in the end, I suspect it will be personal preference on this issue which will outweigh all other factors for most buyers.

Opening myself up to accusations of fence sitting, my head would say Real Sky Pro for the realism, but my heart might favour Flight Environment for the drama. So coming down off the fence, I might be just as much of a sucker for eye candy as the next person, but if you twisted my arm up my back and made me pick only one, I really think I’d go for Real Sky Pro. Even with its option limitations and uglier interface, I’d value a realistic look over any other criteria. Ask me tomorrow and I might have changed my mind though!

Mister Blue Sky…

Never one to let a developer avoid a tricky issue, I probed Real Sky Pro’s developer on the matter. Obviously passionately interested in the subject, Sandon had this to say about it:

I have always desired a realistic sky. The sky is what the sim pilot views the most during flight. Having a realistic backdrop makes for a more enjoyable flight. Also, depth and the visual illusion of flight is enhanced by a realistic sky. I am like many flight sim users, always looking, downloading, or purchasing the newest files. Real Sky Pro is my answer to a realistic sky for FS, since nothing else satisfied my needs. As a user of Flight Simulator myself, the wishful thinking of ‘wouldn't it be nice if I had a sky that looked real in the sim’ is now a reality for me.

A good answer, but more importantly, it confirms an opinion I had formed while testing Real Sky Pro. It’s sometimes a very subtle difference, but I believe these two products are aiming for slightly different targets. To sum the difference up, I’d say this: You’re more likely to win a screenshot contest with Flight Environment, but you’re more likely to fool someone into thinking it’s a photograph with Real Sky Pro.

A detailed examination…

Essentially, all the textures in Real Sky Pro are amendments or variations of the default FS textures, which have then been grouped into a logical sequence to make finding the perfect sky of your choice easy to implement. If creating these textures sounds like it might have been simple, my investigations proved otherwise, and it was apparent that a lot of care had gone into the various tweaks that have taken place to create this product.

Being someone who uses PhotoShop professionally a lot of the time, I can confirm that it is a lot easier to get yourself into trouble with RGB gamut range problems if you don’t know what you are doing, than it is to create something which works well. With this in mind, I was curious to know whether the sky effects in Real Sky Pro were simply a batch conversion followed by a port over from the FS9 to the FSX version, or something more, and so I asked developer Sandon Lyon about this too, to which he replied:

The sun, and effects for the sun, in FS9 are also changed. In Real Sky Pro Edition 1.2 for FS9 (the latest version), I went ahead and performed the extra step to focus on that sim. What I mean by this is; the textures for the FS9 version are tailored to bring out the greatest detail for that sim. Each version of RSP was designed for that sim only. The textures are not just converted over to work in both sims.

The X Files…

Of course I didn’t just want to take the developer’s word for it, afterall this is supposed to be a hard-nosed review, and so it was time to crank up PhotoShop and open up some of the textures to see exactly how much work has gone on…

This probing of the Real Sky Pro files revealed some quite complex tweaks and changes had indeed taken place, in an attempt to emulate the distant appearance of the horizon when viewed from above, through atmospheric conditions.

Below you can see an example of this and it is fairly typical of what I found; notice that the fade of the visible horizon has been raised slightly in order to emulate an inversion layer when viewed from on high through slant range. This is clever stuff and goes way beyond simply putting pretty colours in the sky. I must admit I was hugely impressed when I discovered this meticulous attention to detail.

Paint the whole world with a rainbow…

At this point, I think it might be useful to list exactly what is on offer, to give you some idea of the scope Real Sky Pro covers, and that is certainly a lot:

Dawn 1 features Sunny Gray Lite Dawn, Summer Heat Dawn, Pinkish Dawn, Soft Orange Dawn and Lite Purple Dawn.

Dawn 2 offers you Blue Orange Dawn, Dark Orange Dawn, Dark Shadow Dawn, Golden Dawn and Nice Contrast Dawn.

Dawn 3 comprises Kewl Dawn, Warm Dawn, Silver with Red Orange Dawn, Warm Dawn and Blue Dawn.

Postdawn offers Best Postdawn for Winter, Postdawn Bright Contrast, Postdawn Dark Contrast and Postdawn Sharp Contrast.

Day Options offers a big selection, comprising: Baby Blue Day, Blazing Color Day, Blazing Contrast Day, Blue Lightning Day, Bright Blue Heat Day, Clear Summer Day, Cloudy or Overcast Day, Crisp Sunlight Day, Dark Blue Day, Deep Blue Sky Day, Glowing blue Day, Green Tint Haze Day, Tinted Green Rainy Day, Hazy Day Lite Color, High Contrast Day, Soft Blue Tone Day, Light Blue Haze Day, Sharp Blue Tone Day, Silver Blue Tint Day, Blue Green Toned Day, Nice Blue Sky Day, Pure Sunlight Day, Rain in the Area Day, Rain or Humid Day, Sharp Bright Blue Day, Smoggy Day, Soft Green Tint Day, Winter Day and Winter Wonderland Day.

Presunset offers Best Presunset for Winter, Presunset Bright Contrast, Presunset Dark Contrast and Presunset Sharp Contrast.

Dusk Set 1 consists of Sunny Gray Lite Dusk, Summer Heat Dusk, Pinkish Dusk, Soft Orange Dusk and Lite Purple Dusk.

Dusk Set 2 has Blue Orange Dusk, Dark Orange Dusk, Dark Shadow Dusk, Golden Dusk and Nice Contrast Dusk.

Dusk Set 3 presents you with Kewl Dusk, Warm Dusk, Sunset Silver with Red Orange Dusk, Winter Dusk and Blue Dusk.

Extras for FS9 include Sun Halo File and Clouds, Water Reflections and new frame-rate friendly Replacement Water Textures. Extras for FSX include Sun and Clouds.

All day, and all of the night…

Yes, it was a pain to type all that list in (isn’t reviewing fun?), nevertheless, you can see that you get a lot of bang for your buck, and just about the only type of day which Real Sky Pro doesn’t offer, is a dog day afternoon. So, leaving aside the fact that I always want to slap people who use the word ‘Kewl’ to describe things, I can’t fault RSP for choices.

You might have noticed there are fewer ‘extras’ in the FSX version, however, this is because FSX already has many improvements in this area in comparison to its predecessor, so do not feel cheated by what seems to be an apparent shortfall, because it isn’t.

Tomorrow may be even brighter than today…

Even though Rainy Days and Mondays always got The Carpenters down, Gene Kelly felt like singin’ and dancin’ whenever post-weekend precipitation showed up, and this difference in how people feel about the sky’s endless moods is clearly going to be the crux of any appraisal of Real Sky Pro too.

As already noted, apart from the graphic quality of the choices in Real Sky Pro, which is good, any other criticism is going to be more about personal preferences than the inherent quality of the skies on offer here. In deference to that, below is a series of screenshots to give you an idea of the kind of discriminating changes can be made with RSP, and this is only a small selection. These screenshots were all taken with the same parameters, at the exact same time of day and in the same location – an autumnal dawn in the Falkland Islands:

FS9 original: Dawn
FS9 with Real Sky Pro: Dawn FS9 with Real Sky Pro: Golden Dawn

FSX original: Dawn FSX with Real Sky Pro: Blue Orange Dawn FSX with Real Sky Pro: Golden Dawn
FSX with Real Sky Pro: Nice Contrast Dawn FSX with Real Sky Pro: Pinkish Dawn FSX with Real Sky Pro: Winter Dawn

At the end of the custom-textured day…

Do I like Real Sky Pro? Yes, I do. In fact with so many choices, frankly it would be impossible not to find something I didn’t prefer over the original FS textures, and choice is always a good thing. But being completely honest, I fervently disliked the replacement FS9 water effect in this package, which I thought cycled way too quickly through its glittering animation to be convincing, and appeared to have too much graphical ‘noise’.

But if you are looking to increase frame rates in FS9, the claim that this speeds things up is absolutely true, because it really does. Alas, if only it had cycled slower, I suspect the RSP FS9 water effect would have been very convincing indeed.

The water animation effect I disliked. Needless to say, it is hard to tell how this animation looks from a still shot, so I have taken the somewhat unusual step of posting a clip of this effect in action online.

The FS9 water effect is one of a select few Real Sky Pro offerings that will be getting switched back to the original on my install of FS9. Not the end of the world, true, particularly since it isn’t actually a sky texture of the main package but classed as an ‘extra’. Still, it does illustrate why an automated revert option might be nice in a future update to the utility.

I don’t want to dwell too much on this though, as one personal dislike of mine aside, most textures in this package are actually incredibly well thought out and something of a dream-come-true if you are a screenshot artist seeking subtle realism over in-your-face eye candy.

To keep things honest, I took all of the above screenshots for this review without any other weather generators or cloud enhancements and in mainly clear skies too, so you could get a good look at the basic textures. But it’s when in combination with many of these other utilities, plus real weather downloads from the internet, that RSP’s textures really do come into their own. With this in mind, below are two screenshots that do incorporate other popular add-ons and illustrate this pleasing compatibility well.

FS9 with Real Sky Pro’s Sunset Silver with Red Orange Dusk and Weather Maker RX enhancements. Light really does seem to be bouncing around and filling the air here, in a striking depiction of illuminated clouds which tally well with the distant sky’s tone An interesting example of a bonus conferred by the subtlety of Real Sky Pro’s approach. This shot shows the RSP Sharp Bright Blue Day texture in FSX; the reduced contrast has had the effect of blending the clouds into this sky texture’s paler blue, resulting in the distant cumulous appearing less ‘stuck on’ than it normally would when over the default FSX blue texture. Note that clouds are enhanced here with Weather Maker RX and the Real Sky Pro Sun and Clouds ‘extra’


I think Real Sky Pro will certainly appeal to anyone who can appreciate how much of a genuine feeling of extreme distance these textures offer, instead of simply concentrating on ‘wow factor’ colours. There is some real subtle artistry and particularly astute implementation of what the sky does actually look like when viewed from an aircraft to be found within this package. That said, there is nothing wrong with preferring ‘wow factor’ colours either, however, if that is your disposition, I imagine RSP’s competitor might be more to your liking.

Real Sky Pro is well named in my opinion, as it really does create some very realistic looking skies. Although, it might be a bit more ‘Pro’ with the typos corrected in the GUI and some help file tweaks. It represents good value for money too, with all the intelligent work that has gone into it and it is nothing if not wide-ranging and comprehensive. This is one product where you really can say that the sky’s the limit.

Test system for this review

All versions of Real Sky Pro were tested on a Pentium 4 equipped PC with 2Gb of RAM, running Windows XP, with the most recent MS service pack updates. Both FS9 and FSX had the most recent patches available applied. Desktop colour settings for all the screenshots were 32 bit @ 1280x1024.

Overall test time

Real Sky Pro for FSX and FS9 were tested for a total of approximately 30 hours. Most of this consisting of loading, switching, deleting and changing various combinations of textures, plus subsequent loading of other add-ons to see if any anomalies cropped up. Some long distance flights were also made to look out for any issues relating to texture loading problems, both on accelerated and real time.

Halfway through this period of testing, I received a copy of the updated 1.2 FS9 version, which means this review covers both the 1.1 and 1.2 FS9 iterations of RSP, in addition to the FSX version.


What I Like About Real Sky Pro

  • This is some really clever and subtle work which has a lot more to it than is at first apparent
  • A vast array of choices are on offer
  • Despite FSX compatibility, FS9 is not abandoned, with RSP still receiving updates for the older version of FS


What I Don't Like About Real Sky Pro

  • The help screen needs improving and a ‘Read Me’ should point out possible pitfalls
  • The GUI could do with some tidying



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