Air Photos

[tokoloshe]

I think I heard somewhere that there was a web site that had air photos that might be better than Google Earth - any knowledge or experience ?

[Adventure Racer]

http://maps.live.com/

[Paul Frost]

I have found that sometimes http://www.multimap.com has higher resolution images than either Google or Microsoft.

[Stodgetta]

http://atlas.freshlogicstudios.com/ was the one I mentioned to you

[Adventure Racer]

The logo in the bottom left corner would suggest it's using the same maps/photo database as my suggestion, which does seem to have a lot better detail for much of the country than Google Maps/Earth.

[johnloguk]

That is absolutely awesome, how much time have I wasted over the last year or so with hopeless aerial photographs as templates? I know what I'm doing this weekend

I think this is where we re-start the old debate about whether or not to map every single thicket, because now there is no excuse not to

[SIman]

Another very useful site for looking at different collections of aerial photographs is FlashEarth.

[graeme]

I think this is where we re-start the old debate about whether or not to map every single thicket, because now there is no excuse not to

Only if you're committed to keeping the map updated
regularly. Maps showing where the thickets were four years ago are not helpful.

Ideally, you should. The difference between areas where you can run through the thicket without bother, those where you need to mapread to pick a route, and those where you have to bash through is significant, and stripey green doesn't help.

But if you do, it also opens the question of what is
a legitimate control site...

[swat]

Looking at my house on the FlashEarth site the Google image is much better than the Microsoft one, and also raises the question of how old the photos are - the car parked on the drive looks to be the previous resident's, and we've been living there for nearly 4 and a half years. So it would be easy to draw a map showing where the thickets were then

[graeme]

Yes, I extended the Calder Wood map onto some nice fields/woods from the aerial photos. When I got there with my "base map" it was a fully functioning industrial estate. Which was just fine for parking

[johnloguk]

The other thing to be careful of when using these photos as templates is that they are not all very vertical, some of the angles are quite marked. The age of the photos is very interesting too, because there seem to be different layers of photos across the same area. At diffferent resolutions (heights?) you seem to be able to get different photos of the same place. lincolnsteve saw an umbrella in his garden which had to be only a few months old, then scrolled back and it was gone, spooky! Some areas of Lincoln are several years old, with others brand new, definitely a health warning and caution must be applied. Nice pix though

I also agree with Graeme's comments about the thickets, and I'm not in any particular rush to map hundreds of hawthorns

[Red Adder]

I'm quite impressed with th APs from FreshLogic though in many areas they are taken from the getmapping flyover from 1999-2001 so are starting to date. In EA I find that they give me a good base map and some very useful hints as to where to search. The odd large deciduous tree in runnable conifer plantations (they stand out very well) also make a good point feature. No more need for dodgy tripods.

[IanD]

Flash Earth is marvellous, you can flip between different images to find the best view. Take the point about the images potentially being out of date and not necessarily vertical, so not ideal for mapping thickets. All I'm trying to do however is get the roads about right on a low quality street map for a fun event - I don't need the precision that would be required for a serious street race.

So my question is, can I get OCAD to display one of these images as the background map?

[tokoloshe]

The two sets of earth photos - Google earth and MS VE are both useful. The Google photos are significantly more recent of Cannock Chase, and appear to be no more than about 24 - 27 months old but they are taken with a very low sun angle, good for showing spurs and reentrants but it means that forest edges can have big shadows where it is difficult to see anything. In the open areas you could map where the deer were then.

The MS VE has a different colour balance that certainly makes the path network stand out.

[Paul Frost]

Ian
It is easy to use an aerial photo in OCAD.
Create a JPG from the screen (CTL/PrtSc and paste into Photoshop or any image software and save it).
Have an OS or such map with the roads on as your first background image.
Add the aerial as another background image, make it transparent, and adjust it so the roads line up with the OS map. This will scale and rotate it to the correct position.
Now hide the OS map and dim the aerial photo so you can start to draw your map.