Photoshop, _y.raw files, and USA Photomaps

A year ago there was this thread:http://www.train-sim.com/cgi/dcforum/dcboard.cgi?az=show_thread&om=8356&forum=DCForumID6It came up as I was searching around for info on the penci tool, but this popped up because he was using the Photoshop pencil tool to alter terrain heights and I found it very intruiging. I thought of an idea, but I haven't been able to make it work, but I thought some others might have some useful input.To summarize, the _y.raw file can be opened in Photoshop as a 16-bit grayscale image, 256 x 256 pixels. Looking at the image, it kind of looks like the terrain image one sees in Demex when looking at DEMs.It occured to me that there might be an easier way to dig trenches for river water on my route using these files combined with USA Photomaps. In essence, since the _y.raw file corresponds to a 2048 x 2048 meter tile, it scales to 8 meters per pixel, and that is exactly the scale of the larger arial photos that one can download using USA Photomaps.Now I thought that somehow I could overlay the two images using layers and different opacities to line them up, and then draw in the river bed on the _y.raw file, reset the terrain floor in MSTS, and voila, a new river bed! But Photoshop 6 doesn't do layers in 16-bit mode, and I couldn't really get the images to line up properly.Is there some way of getting the lat and lon coordinates at the corner of each MSTS tile? That might help. All other thoughts appreciated too. Discuss.MarkMoffat Road Tabernash to Phippsburg
106 miles (100%) of mainline track
Currently perfecting yard/siding trackwork

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

RE: Photoshop, _y.raw files, and USA Photomaps, jonathanmlewis, Mar-09-04, 03:38 PM, (1) RE: Photoshop, _y.raw files, and USA Photomaps, DRGWK36, Mar-10-04, 07:44 AM, (2) RE: Photoshop, _y.raw files, and USA Photomaps, markhyams, Mar-10-04, 12:52 PM, (3) RE: Photoshop, _y.raw files, and USA Photomaps, homer13j, Mar-10-04, 06:27 PM, (4) RE: Photoshop, _y.raw files, and USA Photomaps, markhyams, Mar-10-04, 06:54 PM, (5) RE: Photoshop, _y.raw files, and USA Photomaps, lfriddle, Mar-11-04, 11:12 PM, (6) RE: Photoshop, _y.raw files, and USA Photomaps, markhyams, Mar-12-04, 04:46 PM, (7) RE: Photoshop, _y.raw files, and USA Photomaps, homer13j, Mar-12-04, 06:06 PM, (8) RE: Photoshop, _y.raw files, and USA Photomaps, lfriddle, Mar-12-04, 09:29 PM, (9)

Conferences | Topics | Previous Topic | Next Topic

You have got an interesting idea there.In DEM-EX you can move the mouse to the corner of a tile and it will give you the Lon/Lat. You may also be able to find out the Lon/Lat in the RE if you select tile mode. Their may be a more accurate way but I am but sure what it is.http://groups.msn.com/MSTSNarrowGauge

Jonathan Lewis
jonathanmlewis@msn.com

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Mark:
Part of the issue will be the coordinate systems that are used in the different programs and datasets. I've seen numerous threads on that topic, but the times I've read through them tend to leave me confused, so I can't give you much useful guidance on that This is something I hadn't seen before - I clearly missed out on the thread last year - and looks to have some interesting uses. I opened up a tile in Photoshop Elements and it came up very nicely - I was able to see the roadbed that I'd cut using the Y key. One question I had was how the gray scale was set - is the highest level set to black and the lowest to white for all tiles?I also followed the earlier thread (which had a few archived threads itself) and eventually ran across this golden oldie from some guy named JohnCS :I *believe* I can make a DEM importer. I've spent the last 24 hours playing around with different DEM format specs & converters, and the tools are available to get a DEM into a format I can understand without a degree in cartography. (July 4, 2001)We've certainly come a ways since those days!Andy

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

From the way I understand it, the grayscale is set by the tile's floor and ceiling values: Black (0) is the lowest and white (255) is the highest. Although since it is a 16-bit file, there are 65536 levels between black and white, not 256.MarkMoffat Road Tabernash to Phippsburg
106 miles (100%) of mainline track
Currently perfecting yard/siding trackwork

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

I remember that thread, and I posted a follow-up to it (I think it was called "more terrain with photoshop").You can convert those images to 8-bit and work with them in Photoshop normally. When you are done convert them back. Worked great for me. It's how I recreated the twisting Cuyahoga:
Todd

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

LAST EDITED ON Mar-10-04 AT 06:59 PM (EST)

Here is the thread you are referring to:http://www.train-sim.com/cgi/dcforum/dcboard.cgi?az=show_thread&om=8421&forum=DCForumID6Excellent work. You've inspired me to give this a try for the Colorado River snaking through my route.MarkMoffat Road Tabernash to Phippsburg
106 miles (100%) of mainline track
Currently perfecting yard/siding trackwork

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

I am in year 3 of working on my route. In the beginning, I was being very percise in placing river beds, and so on. Now I don't think it is that important any more. I think if you just set the terrain from DEM data, most of the time you can tell where the river bed should be. If you piece several tiles together in photoshop and then edit, you usually can make out where the river bed should be. As for being percise, who is going to be measureing while driving a train down your route? If you can't make out the exact location, fudge it. Just try to get close and make it look realistic.An idea I haven't tried, if you really want to line up a tile with the photomap, mark some reference points with photomap. Convert them to markers. Load the editor and use the terrain editor to raise or lower (whichever will stand out the best) the single point under the marker flag. Now load the tiles into photoshop and your points should be easy to spot and line up with the photomap overlay. Larry

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Well, I've gotten this thing to work after all. It really speeds up the process of doing the river bed, and it only takes about 15 minutes per tile (once I got it down).I decided that I should overlay the _y.raw image with the topo image in Photomaps (rather than the arial photo), because then using the magic wand tool, I can select the blue river bed, and then it's easy to paint in the river bed on the .raw file using the airbrush tool. Save and voila!I've also found it useful to adjust large swaths of flat terrain that was a meter or two above the tracks, when it should have been a meter or two below. Here are some shots of the Colorado River near Kremmling, CO:Also of note, I was able to grab the lat and lon coordinates of the tile corners from Mosaic (you can zoom way in and get a very accurate reading), and then I plugged them into Photomaps. Unfortunately the tiles don't line up as perfect squares, they are actually a bit skewed, a bit like a trapezoid. You can see the effect quite clearly in DEMEX, as the tiles are all skewed there. I assume this has something to do with the world being round and not flat. Go figure.Thanks again for everyone with their input on this. It has definitely made my life easier!MarkMoffat Road Tabernash to Phippsburg
106 miles (100%) of mainline track
Currently perfecting yard/siding trackwork

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Glad to help. Looks great.Todd

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

I agree. Looks very real. Good Job. I'm looking forward to seeing your work.Larry

Alert | IP

[ Home | MSTS Forum | MSTS FAQ | File Library ] Copyright © 2004 by Nels Anderson. All Rights Reserved.