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Jack Erbes
 
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Flemming Torp wrote:
snip
Thank you Jack for a very thorough, relevant, and solid input!


You're welcome, I'm seeing this on rec.boats.electronics and it is a
group that knows a lot and will share it helpfully. I've learned a lot
here too.

Another newsgroup that may be a little more focused on gps, navigation,
and some of the details of your questions here is sci.geo.satellite-nav.
I think there is more discussion there of the specific devices and
processes you want to do.

snip
This is exactly, what I want! But - unfortunately - this is a 'world'
I've never been into ... I have been told, that the maps in DLSK are
stored in a xxx.it - format, that is not compatible with anything else
in the world ... and I'm not in a position to challenge this statement
... I will have to study this whole subject in more details. I will go
to the library. Maybe you have some relevant references?


I don't really have any library references, what I know has been learned
through experience, newsgroups, web pages, and just playing around with it.

I do not really
know what calibration - in this context means - so I feel I'm pretty far
from the target ....


It is not that complicated, after all I think I get it. :)

If you download SeaClear II and look around on that web site, there are
several documentation files that will give you the basics of calibration
and how to do it. The Ozi-PC trial version also has a good explanation
of it. I am getting more comfortable with map calibration but am far
from an expert and have not used it much. Basically it is mapping the
x,y pixels in a map image file to a geographical reference system. You
tell the program the lat/long postion of a number of specific pixels
that are at known geographic points and the program then maps all the
other pixels to that geographical reference system. That is a
simplistic explanation and maybe not even quite correct.

Compared to my 'long term solution' or alternatives, I do not find the
prices of the two ozi-programmes prohibitive.


That was my feeling when I bought it, I consider it a real bargain at
the price.

snip

I may understand this, when I start working with it ...


I think you will, I felt the same way when I started but wanting to do
it and being stubborn will overcome a lot of ignorance.

snip
That's a nice solution. My PPC supports MMC and SD memory cards. I have
started with 256MB, but can see, that prices on memory cards are going
in the right direction ...

My primary challenge - I understand - is to learn how to 'calibrate and
convert' my DLSK-maps into a format, that ozi-CE can read ... As the
boat is still packed in ice, I may have some time during the coming
weeks to study map-calibration, different map formats, conversion
programmes etc. It's a completely new world for me - but fascinating -
and a little frightening ...


By it being mentioned on these groups, I would be surprised if someone
who has already done it does not speak up. There is a image file format
called tiff/it that may have something in common with your DLSK files.
It may be that you already have a bit mapped image file but that it does
not have a common name. It may just need to be "figured out".

If you familiarize yourself with map calibration with Ozi and SeaClear
and have more questions, I recommend you try asking them on the
sci.geo.satellite-nav newsgroup. I think you'll hit a little better
audience for the question there.

Good luck, feel free to email me off the group also if you think I can
be helpful.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)