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The VLG
2008-03-12, 03:09 PM
Hey,

I'm hoping for a bit of feedback here, I've been asked to look into creating 'photomontages' of green field sites showing the before & after effects of major highways.
I know that a firm could do it for us & that they use 3d max, is this a good piecs of software for this?
I thik that the idea wold be to have a 3d model with aerial photograpy draped over a 3d terrain model & the to show the same with the new road/junction..also to show some views from fixed locations, using photos taken on the ground...
Any feed back welcome...there was also mention of 'KeyTerra-firma' and photoshop in the work

stusic
2008-03-12, 07:07 PM
I think the best use of max in a situation like this is to use it to visualize the future effects of a project. If the project has already been completed, I think photographs would be best suited. If the site is unaccessible or photographs otherwise couldn't be taken, then max may have a use.

loydg
2008-03-13, 04:23 PM
If the project has already been completed, I think photographs would be best suited.

Good advice, Phillip. There's no point in building the existing unless you are planning to do a transition between it and the proposed in a full animation sequence.

If you do end up using photographs as the back plate (which I would also suggest), Max has some great camera matching abilities. There is a Camera Match utility in Max, but I find it "so, so" when it comes to certain rural scenes as matching data may not be accurate or easy to locate. If you need more info on camera matching, let me know.

The VLG
2008-03-13, 04:30 PM
Thanks for the replys, yeah they would be mock-ups of future projects, the I get impression is that we'd be looking to produce both birds eye views & on the ground views (which is where the camera matching would come in)
I assume that there is a facility to map a georeferenced (orthorectified?) aerial shop on to a 3d terrain model.

stusic
2008-03-13, 07:17 PM
I assume that there is a facility to map a georeferenced (orthorectified?) aerial shop on to a 3d terrain model.

I have no idea what you just said. :shock:

Steve_Bennett
2008-03-14, 05:45 AM
I have no idea what you just said. :shock:

He said:



I assume that there is a facility to map a georeferenced (orthorectified?) aerial shop on to a 3d terrain model.

Did that come through this time? :beer:

The VLG
2008-03-14, 08:23 AM
I assume that there is a facility to map a georeferenced (orthorectified?) aerial shot on to a 3d terrain model.

A photo from somewhere really really high looking straight down that has been tweaked to fit proper co-ordinates... (http://en.wikipedia.org/wiki/Orthophoto)

loydg
2008-03-14, 01:27 PM
I think I got the gist of it. You have a couple options, but both would require getting access to the data. Luckily, the USGS has that data and for free:

http://seamless.usgs.gov/

Depending on the location of the project, coverage, resolution, and dates may vary. I will typically grab 1/3 arc second DTM data and the most current and highest resolution satellite aerial I can find. Some rural areas don't have great coverage so don't be surprised if your query comes back a bust. There's a little tutorial at the site that gives instructions how to use the search tool and such.

We use Global Mapper to put the DTM and aerial together and get the datum correctly aligned (that last is mostly GIS talk that I'm still picking up and trying to understand). We will export raterized DXFs for the terrain and Tiffs for the maps. GM will setup UVW coordinates on the objects so they map easily. Trees and context buildings aren't necessary, but are nice frosting.

If you decide not to go the terrain route, at least you can do a plan shot with the proposed model over the aerial. Either way, theres no need to camera match to the photo if you have the imagery in the model. Only your ground shots will need view matching.