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LuisFelizTirado

Photo Scenery Scale

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I am making photo scenery of Pueblo based on Aerial photography (1 ft scale)I finally found a GERAT source for the photos I need, but I am being asked what scale I need the photographs. As in what zoom in I need. What is the best scale of zoom to get? I think for 4000 feet flying above the city that 1:2000 scale is good, but I want to be sure I do this right.Thanks for any advice. Again the images are 1 foot per pixel.

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Here's a little advice or input that you may find useful.Let's use my Mount St. Helens Scenery Package for an example. Right now, I am working on a photoreal ground scenery package for Mount St. Helens in Washington State that will replace my previous upload here at AVSIM with an enhanced resolution of 5 meters per pixel. The base image, after acquisition and cropping, was 7500 pixels wide by 5500 pixels high. From there, I made the necessary enhancements to it, such as removing imperfections, checking for necessary edits (for accuracy purposes) and applying a brightness/contrast adjustment filter as well as adjusting the hue.After the inital adjustments were made, I increased the size of the image to 11,500 pixels wide by 8433 pixels high. It resulted in a 153% increase in size, or roughly a 2:1 increase. I then applied a slight "Unsharp Mask" filter followed by a "Sharpen More" filter to enhance the detail lost by increasing the size of the image. The reason for increasing the source image size and then sharpening it in a photo editor is to reduce the "detail washout" created by the resample process. In cases where the image is of a higher resolution, it is generally best to increase the dimensions even further.As a side note, I do not recommend using the Terrain SDK supplied by Microsoft. The best program, I have found, is Photo Scenery Maker. It utilizes the files within the Terrain SDK, but provides a real simple, easy-to-use interface and the easiest calibration methods available.

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Hello Christopher,Sounds like a great project. One foot per pixel is very detailed. You can distinguish houses and even cars, very good for this purpose.The Microsoft Resample program that is always used to make custom ground textures will always resize source images to a resolution of about 4.77 meters per pixel.Your proposed source is about 0.3 meters per pixel, much more detailed than what you will get as ground textures. So, unless you want to have this image for your own use later, and if you have to pay more for such a detailed image, then you can probably better buy a lower-resolution image.To give you an idea, most of us have resized source images to the standard 4.77 (or 4.8) meters per pixel before putting them through Resample.And, Microsoft seems to have used 8 meter per pixel images for the custom ground textures included with the game. Or, so it seems to me. But, maybe this was just due to a lack of good pictures back then.Anyway, in short, it really depends. The textures will be resampled to a lower resolution no matter what. So, unless it is really expensive, get this high-resolution photo if you want.Best regards.Luis

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So, as set before if you place it on the terrain using the mesh techniques a source photo of 4 meter per pixel is detailed enough (for a good looking final image you can better have a little bit too much resolution it seems).But if you also have an airport around, where you can make the ground flat and place ground polygons with other techniques (non-mesh), you can for example place 1 meter per pixel resolution photos there. This works best in a small, flat area.In theory the 0.3 meter per pixel could also be placed this way, but depending on the size of the area your PC might not like it. I once tested with 0.16 meter resolution for the Amsterdam Schiphol airport and my PC totally came to a halt. It was just swapping to load all those textures.

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CoolOkay I got all that, and I appreciate it, guys. My main question, though, was that the providor of the pueblo County photos gives the option to have the photos scaled like topo maps or something, such as 1:10000 or 1:20000 or 1:5000, etc. I was wondering what physical scale to get th photographs so I would be sure I would NOT have to enlarge or reduce the sizes of the photos other than resampling.FYI I have no cash for buying ew programs at this time, so i am using one I already have - FSSC.

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If it's small size you can get away with about 0.5m/pixel.Checkout our HSP LGKO scenery. I used an aerial photo as a source with resolution of 2500pixels/inch, finally sampling it down to 512pixels/inch and got about 0.5m/pixel resolution. Shows great in FS without degraded performance.But as I said, it's a rather small area about 3km x 500m, so I ended up using 16 1024x1024 bitmaps 555-1 compressed 3Mb each without mipmaps.IMHO any texture larger than than that (3Mb) can cause FS to crawl.As an example only, I will mention Malta intl airport. The apron was made up by 2048x2048 16bit bitmaps if I remember right. My PC couldn't handle it, and during approach I had a very nice slideshow.After I converted each of those images to 1024x1024 555-1 without mipmaps, I got a nice smooth performance without loosing too much detail, and the airport still looks spetacular.George DorkofikisAthens, Hellashttp://online.vatsimindicators.net/811520/1704.png

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K thanks. :-) I'll start with the 2500 and go from there.Also I just downloaded that other program mentioned above (Photo Scenery Maker) and will try it after college classes tonight. :-) Many thanks for that suggestion as well.

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Hi Christopher,>My main>question, though, was that the providor of the pueblo County>photos gives the option to have the photos scaled like topo>maps or something, such as 1:10000 or 1:20000 or 1:5000, etc. >I was wondering what physical scale to get th photographs so I>would be sure I would NOT have to enlarge or reduce the sizes>of the photos other than resampling.One thing you should always remember is that in FS the images have a fixed size in degrees. So their borders are all at a certain lat or lon. So if you buy a photo that is in meters, you will always have to do some correction to map it onto the degrees. So if you are buying/getting photos, always make sure they are int eh WGS84 projection for example and that you know the lat and lon of the borders. That makes placement a lot easier with the SDK tools.

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Aye that was one of my main issues. Fortunately I have a little trick I am using for KPUB . . . in this very localized scenery of the city of Pueblo I am using the airport as a reference for prcise positioning of the photographs, and then the airport is going to be greatly enhanced because I am going to use the photo background to lay precise tarmac improvements and buildings for the industrial park.Later on I plan to learn how to use that photo scenery maker, but for now I am doig all of my work in FSSC :-)I also found that my question above was very irrelevant, as scaling of the photo has NO impact at all on a specific method for laying out. For example, I had an email from an individual swearing to use always 1:2500 photo sizes, yet FSSC has a precise scale of 1:4000 **shrugs** So I guess my question got shot out the window when I found that different programs use different scales for editing.Now when i go to add the rest of the Pueblo surrounding areas, I will indeed need to use that method of LAT/LONG as they will be seperate areas and no airport to reference photos off of. So many thanks for that :-) Definately worth having in me notes :-)

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ISTM that "scale" is kind of useless, without a resolution with it. For example if your screen resolution is 90 dpi, then you would need a scale of 1:1080 for each screen pixel to create the source resolution of 12" per pixel. I did a scenery with 24 bit RGB source image @ 0.3m resolution. I saved as tiff and it was 1.5Gb for a relatively small area. So, I resampled it to 1.2m which made a reasonable filesize. Using SBuilder, I built the 1.2m resolution "Hi res" photo polys which use a 1024x1024 texture in -8 format for each LOD13 area. Each texture is about 683k in this format. I have seen some discussion that -DXT may be better, but I haven't tried that. I thought I read something in the sdk saying to use -8 and that is what SBuilder creates.scott s..

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"And, Microsoft seems to have used 8 meter per pixel images for>the custom ground textures included with the game. Or, so it>seems to me. But, maybe this was just due to a lack of good>pictures back then."LuisEverything (generic/aerial imagery)terrain related in the product since FS 2002 has been run at the 5 meter resolution.And yes, there's *way* more source available now :)Cheers,Jason

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This is an informative thread - specially the input from those who've actually tried higher resolutions. It should be read by those who, in other threads, are demanding ever more resolution, It important to remember that, whatever the resolution of the underlying bitmaps, we're ultimately limited by the resolution of the screen - the last step. A typical 19" screen will be 400 mm wide and 300 mm high and will be viewed from about 600 mm. At 1024 by 768 this means that a pixel subtends an angle of 0.00167 rad. This is equivalent to 4.8m at a distance of 2880 m. This implies that, at greater distances, each on-screen pixel would be composed of more than one 4.8m pixel and you wouldn't be seeing the resolution of the bitmap.Adopting 0.3m/pixel instead of 4.8m/pixel increases the file size by a factor of 256. So, for the same area, a bitmap would be 10.9M bytes instead of 47.7k bytes - which is likely to slow down things a bit, as well as filling up your hard disk!

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Thanks for the info, Jason. I was basing my estimation on the Niagara source image, but, as I am no expert, obviously was wrong.Best regards.Luis

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