PhotShop 'scratch disks' question

[Guest Colins2]

Andrew,I have tools at work that will do the conversions.My idea was that if you had the exact coordinates of the corners of your stitched-together image and then put the converted coordinates into the .txt file, I think that the Fly! editor might sort out the projection problems for you.I haven't tried this myself, but it has to be worth a go.I have tried skewing and distorting images to make them fit, but as you and Dave have found, it's not very satisfactory.When we use TerraScene, we produce a rectanglar image with exactly square corners. The projection of the image is a sort of Mercator, i.e. the lattitude is varied to keep the longitude lines straight.The Fly! editor sorts this out without problems, so it should work for what you want.If you want to try this, mail me the UTM/NGR co-ordinates of the corners and I'll convert them for you.Colin

[Guest]

ColinThanks once again for helping sort out this out.This is such an interesting thread now I feel like re-starting it so that others (not interested in PhotoShop problems!) might pick-up on it. However to continue here for the present.We do need to convert the UTM adjusted pics to WGS84 then so I'll try and work out co-ords for a suitable Globe Tile and pass them on.The problem is that you don't know the boundaries of each TS2 made Globe Tile and you have to start by placing pics on a known location (ie Fly! runway) and building up from there.Even when you completely cover the TS2 Globe Tile image with pics you discover that the edge of your TGA image doesn't infact become the edge of the scenery area when podded.Don't know why but for instance the millenium dome exists in my Heathrow Zone (255-170NE) but is excluded when it's put into Fly!Perhaps I could use one of the 'GPS guide books' that give co-ords of major places to discover the exact edges for you. Elrond's SceneryHelper used the pixel positions from your graphics programme to relate them to Fly! positions didn't it.Thinking hard!DaveT

[Guest]

ColinIf I take a finished 'scenery composite photo' and replace the corner photos with the equivalent 'map' ones I would be able to match each corner with a real 'Ordance Survey' map to find the National Grid reference for you.You could then try and convert to WGS84 to produce the text file for the Fly!slicer. My 'composite photo' might well not closely fit any specific Globe Tile boundaries therefore but would be amply big enough for the slicer to use.Paul and myself are keen to be able to join up adjacent scenery areas and I had decided that I needed to work on the Fly! globe tile structure as a way of facilitating this, along of course with the fact that you made available an alignment method when TerraShape came out!We would ideally wish to produce definitive details of the re-scaling of the source photos that we require to do to produce an accurate alignment in the Fly! world.Anyway I'll find some freetime to produce those National Grid co-ords so that you can look into helping.Many thanks as always.By the way have you really managed to get your copy of PhotoShop to open 800Meg TGA's??DaveT

[Guest Colins2]

Hi Dave,Yep, that should do it.The co-ordinates need to be as accurate as possble.Globe tiles are *relatively* unimportant for this, however;1) Scenery matching is easier on a globe tile basis.2) You know exactly where you are if you use globe tiles.3) Fly! works on globe tiles or at least the ground tiles that make up the globe tiles.Just fire up TS2 and create a project for the area that you are interested in (complete globe tile) and then save it. It doesn't matter if you have data or not, the txt file that TS makes will give the exact corner co-ords in lat/long (WGS84).Do as you suggested with your mosaic of photos and find the exact corner co-ords, probably in UTM style, and I'll try and convert them for you. I wouldn't have the conversions for the NG itself, but I saw UTM coordinates on the OSGB maps as well.Elronds utility is quite good, but also has a meridian bug! - watch outI discovered this and made an Excel spreadsheet to do my own. It's not difficult, it is just pixel based.Unfortunately, I don't have a 800mb+ image here at home to show you, but, yes, I can open them, no problem.I am running Photoshop 6 here and at work.It is a slow process, but they do open eventually.I have XP pro and 512 mb ram. Windows manages my swap file and photoshop manages it's own scratch disks. The only thing I can say is that the first scratch disk is set on the installation drive.Basically, I haven't done anything at all; It just works.I haven't tried v7.0 yet, but it is at work so I'll see it soon enough.RegardsColin

[Guest Paul Brooks]

Hi David, I tried a small experiment starting with the shape file for the airports in my egcc tile and placed the mega jpeg (I use jpegs as they are easier to manipulated and move from computer to computer) on the egcc runways and I found that to make them align exactly I had to scale to width 46% height 46.75% and rotate clockwise 0.72.This placed both runways exactly.Then I placed the Woodford jpg to the same scaling, but though the runway length and width was correct no other part of the jpg fitted i.e. the roads and fields etc.I then placed the Liverpool jpg to the same scaling but found that I had to alter the rotation to 0.1, then I placed Hawarded to the same scaling as Liverpool but that didn't fit either, so I decided that the easy way was to play God and move the offending runways in the graphic to fit the shapefile.I do not think that it is possible to arrive at a universal scale for all the tiles but hopefully a standard scale can be arrived at to enable scenery tiles to match each other.The point I'm tying to make is that it appears that each mega targa or jpg would have to be scaled individualy, which would be an enormouse task.I hope this makes sense!Thanks for the offer of upload, I'm amazed that it only takes minutes for a 150meg file, I will contact you via your e-mail address when I am satisfied that I can improve the tile no further.I also managed to open a 800meg targa file via Photoshop 4 on the pc but only to check that Terrascene had made the correct shapefile, but I didn't do any alterations to it as I find that that seems to give the pc problems and is very slow compared to the Mac. I suppose its a question of "horses for courses".Paul

[Guest]

Interesting Paul.I've noticed that I can get 'a better fit' by manually aligning each jpeg (to within the 1 pixel that PhotoShop allows)than I get using MegaPatch but it isn't worth the extra hard work in the end.Hoping we can find a 'best fit' re-scaling though in the end.I'll get back to you (and andrew and Colin) if I get somewhere soon.DaveT

[Guest]

On the original PhotoShop problem by the way-going back to PhotoShop 5.0 allowed me to open the 815 Mb full Globe Tile, so it's a problem with PhotoShop 7.0 that stops such a large TGA image from opening. As I said before once converted to PhotoShop .PSD format I can open much much bigger images in PhotoShop 7.0