Clear Images

[Anonymous]

I am working on a project that is requiring all sheets to have an aerial image in the background of every sheet.  I am currently using the GeoMap and clipping the images out by using the GEOMAPIMAGE command.  The majority of these images are very clear but we have been running into areas where the images are very blurry.  Does anyone have any suggestions of other ways or avenues that I could use in order to obtain crisp clear images?  Thanks in advance.

[Alfred.NESWADBA]

Hi,

>> but we have been running into areas where the images are very blurry.

When you look to BingMaps (using Internet Browser) to these areas, are they blurred already in that locations?

You might also try to use command _MAPIOPTIONS and raise the memory, not sure if that might help for that type of imaginary too.

- alfred -

[ChicagoLooper]

Yes, GEOMAP is a convenient method to insert aerial photos behind your line work. Unfortunately two issues come with this method. A) whatever image and whoever your image source, you are relegated to their highest resolution, B) their camera angle when photo is taken is not always ideal.

Geomap uses Bing, which doesn't have the best resolution--good for reference but lousy for your deliverables. Camera angle, regardless of image source, is ideal only when photo is taken from directly above. If camera isn't above your target property, then you'll see building walls. You only want to see a building roof, not a wall. This parallax is proportional to building height, the taller it is, the more wall area you see and ground level entities e.g. sidewalks, might be hidden 'behind' a building because it appears to 'lean over.' Despite its ease of use and convenience, Bing maps shouldn't be your go to image source.

Try that other 'popular' and ubiquitous FREE map service. Geomap doesn't even come close to their aerials, especially their pro version. If you don't have 3rd party software to work in combo with their maps then you'll have to GeoRef the images you save (yes, you can save images) manually during insertion.

Put two pushpins down before you save the image. During insertion of a pin, the lat and lon of insertion will be shown. Write down the lat and lon (decimals are fine, better than DMS). Hint: instead of giving the pins a generic name such as pin 1 and pin 2, use the actual lat/lon as the name itself, this way when you insert the image, you'll see the 2 pins with their 'name' (lat/lon) adjacent to the pin. In cad, insert the image. Then when you are manually positioning the image, you can use the push pins as 'known' reference points.

Notes:

1. Save a bigger image than necessary, bigger than what's needed to fill you viewport.   
2. Put the pushpins in opposite diagonal corners far enough apart so they won't show in your VP.
3. After you click 'save image' in the mapping program, there's an option to select 'maximum' resolution.
4. Don't use the default yellow pushpins, they lean to the side and are asymmetrical. Pick something that is symmetrical like a square w/plus sign or a circle. It'll be much more easier to GeoRef using something other than a leaning type of marker.

Image below is NOT georef'd. It has two red pushpins. Pin's title was typed in and is adjacent. It is the actual lat and lon of the pin. You can use these pins to GeoRef it in modelspace. Pushpins were 'styled' prior to saving the image. Once inserted you can use Raster Design or 3rd party software to make it a GeoRef image. All labels in the map were turned off for clarity. (Note: This is a copy of the actual 'saved' image. The original was too big to attach to this post and the substitute below was used instead.)