Characteristic features of the cartographic documents:

- the cartographic documents can be stored in 2D or 3D form

- the 2D cartographic documents can be single sheets or series of sheets; they can, however, be bound in volume(s), too. They are regularly coloured, use tiny signs (small letters of 1 mm in size or graphic sings in this size).

- their dimensions are changing, often larger than A0 (70x100 cm). Paper, paper mounted on linen, parchment, silk etc. can be as their supporting materials.

- they have determined mathematical structure; indexes or other data collections can be attached to them

Digitising is connected with their features and their size:

a. directly:

- with scanner

- with camera scanner

b. indirectly:

- using traditional photograph (slide) in size of 6x7, 9x12, 13x18 cm etc. The slide is used at scanning in this case.

The quality of automatic retrieval of the indexes, data collections is not the required one, especially at the case of old maps. These data need to be stored manually in databases.

For further processing of the digital data set, the vector format would be the best solution, but data sets only in raster format are being built recently. The memory demand of a digitised, coloured map in size A0 reaches 700 MB.

Conservation of the cartographic documents can be successfully solved using digitising technology these days.

Such a high data set can hardly be processed by a PC, the access to it on the internet is unsolved.

Recently using packing procedures causing no losses can solve this only. The best of these is the Mr.SID program, although lots of image processing programs do not support it.

The Internet service of large data sets needs server with high capacity; without owning such a server this service of the National Széchényi Library can be accessible via an external server.

An other problem for the users is the significant difference between the monitor's size of the PCs and the sizes of the maps what difference causes that the user can see only a part of the map on the screen. At web service a small guiding outline of the maps can considerably enlarge the size of the data set.

A special problem can be if the cartographic documents are accessible in an image database. For this reason the AMICUS database of the Széchényi Library was previously connected via URL, now via URN. Using this technology the user of the library's data set can also access the digital image of the cartographic document immediately.

This solution is quite new, also internationally.