On Mon, 18 Sep 2006 07:45:00 -0400, "Gerald"
wrote:

I am convinced that raster charts are the way to go and that, perhaps, I
am not in the mainstream and have made it to the position of 'old-fart'.

I hear you, vector charts definitely takes some getting used to, and
for some things raster is clearly superior.

For the last two years I've had both side by side, raster on
PC/Maptech, and CMAP/vector on a Furuno chart plotter. I agree with
much of what you say, but have come to appreciate some of the benefits
of vector as well.

One thing that vector does much better is "zoom in" and "zoom out".
When you zoom a raster chart the text fonts and pixel details get
larger and smaller also, which renders them illegible very quickly.
Vector on the other hand automatically compensates for zoom level so
that font sizes are constant, and detail pixels are adjusted to an
appropriate size. The net result is that fewer vector charts are
required for any given area since detail improves as you zoom in,
unlike raster which requires an entirely new chart to show greater
detail.

The other area where vector is clearly superior, is "course up" mode.
Course-up is a much more intuitve way to view chart data, particularly
in close quarters. However, if you display raster charts "course up"
on anything other than a north bound heading, chart text and symbols
appear rotated out of the normal vertical orientation, and are
actually upside down in south bound directions. With raster charts,
the text and symbols are automatically rotated to stay in normal
orientation, making course-up much more useful.

On our boat I generally do all of my route planning on the PC using
raster charts since Maptech is very good at that, and I can do
everything off-line in the comfort of the main cabin the night before.
While running I keep the PC zoomed out to show the big picture and the
route information such as range/bearing to next waypoint, total miles,
time-to-go, etc. On longer legs I will transfer the next waypoint
details to the Furuno chart plotter as well. The chart plotter is
usually left in course-up mode and zoomed in to a fairly high level of
detail where chart symbols are resonably uncluttered and easily
readable.

Another superior feature of the chart plotter, unrelated to
vector/raster, is screen brightness and clarity. The brightness level
is fully adjustable for comfortable viewing all the way from direct
sunlight to complete darkness. No PC or flat panel display that I
have used has a comparable level of brightness or adjustability.

With the right selection of features and options, the chart plotter
has some other worthwhile attributes. For example our Furuno system
has the ability to super impose radar data on top of the chart display
which is very useful for identifying unkown radar blips and determinig
whether or not it is a navaid or probable boat. Since this feature
requires rotating and zooming the chart data to match the radar
display, vector charts are clearly the right choice.

Since this feature
requires rotating and zooming the chart data to match the radar
display, vector charts are clearly the right choice.

Hmmm, no it doesn't. At least not on a Raymarine E-80. I can overlay radar
on top of charts in any orientation. I tend to prefer North up orientation,
but the admiral likes it to rotate with the heading. It's a snap to change
between them.

When dealing with charts at the helm I find vector more useful. When
plotting courses on a laptop, however, raster seems better. For me the
difference is what I need to know RIGHT NOW versus planning what I where I
feel like going at some later time. The vector charts with the ability to
zoom in/out quickly and without losing detail (getting grainy like raster)
are of tremendous help when actually moving. Granted, I'm usually at 30kts
in a powerboat; those in sailboats might have a different sense of urgency.
But when I'm planning trips ahead of time I find the extra detail they've
got on raster charts to be rather handy. I generally use Coastal Explorer
(aka Maptech Chart Navigator Pro) with Maptech digital charts. On the
chartplotter I use a Navionics platinum chip.

If faced with having to choose one over the other I'd probably go with
vector because of it's benefits (for me anyway) while underway and just use
other sources for trip planning extras.

On Mon, 18 Sep 2006 11:56:53 -0400, "Bill Kearney"
wrote:

Since this feature
requires rotating and zooming the chart data to match the radar
display, vector charts are clearly the right choice.

Hmmm, no it doesn't. At least not on a Raymarine E-80. I can overlay radar
on top of charts in any orientation. I tend to prefer North up orientation,
but the admiral likes it to rotate with the heading. It's a snap to change
between them.

I agree that it is theoretically possible to rotate the radar image
instead of the chart image. In practice however, virtually everyone
is used to looking at radar images in "heading up" format.

"Wayne.B" wrote in message
...
On Mon, 18 Sep 2006 07:45:00 -0400, "Gerald"
wrote:

I am convinced that raster charts are the way to go and that, perhaps, I
am not in the mainstream and have made it to the position of 'old-fart'.

I hear you, vector charts definitely takes some getting used to, and
for some things raster is clearly superior.

For the last two years I've had both side by side, raster on
PC/Maptech, and CMAP/vector on a Furuno chart plotter. I agree with
much of what you say, but have come to appreciate some of the benefits
of vector as well.

I have never actually used vector charts underway. Marine vector only in
showrooms and boatshows. Like it or not, I suspect I am going to have to
make the leap -- grumbeling all the way, but doing it. I am in the process
of downsizing and won't have the room or 'trons to do what I am used to.

One thing that vector does much better is "zoom in" and "zoom out".
When you zoom a raster chart the text fonts and pixel details get
larger and smaller also, which renders them illegible very quickly.

Again, something I will have to 'learn to love'.

Vector on the other hand automatically compensates for zoom level so
that font sizes are constant, and detail pixels are adjusted to an
appropriate size. The net result is that fewer vector charts are
required for any given area since detail improves as you zoom in,
unlike raster which requires an entirely new chart to show greater
detail.

Logically that should be the case. The examples that I have seem in demo
machines don't have much of the detail I am used to seeing to begin with, so
the zooming effect doesn't matter --- the details ain't there. It may well
turn out that that is more a function of the demo, demo operator or
excessive nit picking on my part. In the long run, if it isn't totally true
now, it will be someday.


The other area where vector is clearly superior, is "course up" mode.
Course-up is a much more intuitve way to view chart data, particularly
in close quarters. However, if you display raster charts "course up"
on anything other than a north bound heading, chart text and symbols
appear rotated out of the normal vertical orientation, and are
actually upside down in south bound directions. With raster charts,
the text and symbols are automatically rotated to stay in normal
orientation, making course-up much more useful.

This is one of those interesting areas that make vector a selling point for
some, but not me. Having done paper charts (read north up) for so long, it
is natural for me. I have tied using my Maptech in course up and found it
disorienting. My minds eye sees the world in a north-up orientation,
looking at something in a heading up orientation feels, well, just wrong.
No, I didn't give it a real chance. I tried it for half an hour ro so here
and there, pronounce the foolishness of it all, and go back to north up.
There are some paper charts strips in the Chartbooks that are turned to
other than north up to optimize printing, I turn the North up too (chart
book cockeyed). Ok, I have found the problem: I AM and old fart!!!!!!


On our boat I generally do all of my route planning on the PC using
raster charts since Maptech is very good at that, and I can do
everything off-line in the comfort of the main cabin the night before.
While running I keep the PC zoomed out to show the big picture and the
route information such as range/bearing to next waypoint, total miles,
time-to-go, etc. On longer legs I will transfer the next waypoint
details to the Furuno chart plotter as well. The chart plotter is
usually left in course-up mode and zoomed in to a fairly high level of
detail where chart symbols are resonably uncluttered and easily
readable.

I had a similar drill. After I loaded (or selected) my route in Maptech, I
would export the Waypoints into my GPS system. If the computer crapped out,
everything was ready to go on the GPS. This was especially useful when
offshore. I had the autopilot set up to take steering commands from either
the computer or the GPS. Again, if the computer died, I would not actually
have to steer the boat - heaven forbid!


Another superior feature of the chart plotter, unrelated to
vector/raster, is screen brightness and clarity. The brightness level
is fully adjustable for comfortable viewing all the way from direct
sunlight to complete darkness. No PC or flat panel display that I
have used has a comparable level of brightness or adjustability.

I had high brightness OceanPc displays in a pilot house environment, so this
was not a problem. It will be an issue in the new boat: no pilot house.


With the right selection of features and options, the chart plotter
has some other worthwhile attributes. For example our Furuno system
has the ability to super impose radar data on top of the chart display
which is very useful for identifying unkown radar blips and determinig
whether or not it is a navaid or probable boat. Since this feature
requires rotating and zooming the chart data to match the radar
display, vector charts are clearly the right choice.

While all of this has been available in the PC / Raster chart arena,
certainly not a cost that compares well with the integrated solutions
available with vector charts. This is a great feature and I look forward to
playing with it. I suspect this really requires the use of a gyro compass
to get a sufficiently stabilized overlay. I had a gyro on my last boat and
it made a big difference in ARPA accuracy.

I hope I have that whine out of my system so I can just get on with it...

I agree that it is theoretically possible to rotate the radar image
instead of the chart image. In practice however, virtually everyone
is used to looking at radar images in "heading up" format.

There's no theory involved, the E-80 does it. At least from the perspective
that someone that wants to see the radar overlaid on charts can do so while
the charts are being displayed in a 'heading up' orientation. Or if
they're looking at the chart in 'north up' orientation it'll likewise
overlay the radar. We use these two modes all the time.

Uh well, yeah, when looking at *only* the radar scope rings it's rather
standard to see them in heading up format. I think you can show it in north
up mode as well. Although I personally don't see myself ever using it that
way.

Logically that should be the case. The examples that I have seem in demo
machines don't have much of the detail I am used to seeing to begin with,
so the zooming effect doesn't matter --- the details ain't there.

Get a demo with one of the better charting chips actually loaded. The
default chart data is pretty weak in most chartplotters. Mainly because
there's limited memory in them and with worldwide marketability it'd be
rather impractical to install any (as in, nothing's 'local' when you're
talking worldwide).

For me the speed with which I can zoom in/out while ALSO getting better
clarity makes vector charts superior. But this only when underway. I like
using raster charts for planning but they're too slow to pan around and
don't have close enough detail for the places I usually frequent.

This is one of those interesting areas that make vector a selling point
for some, but not me. Having done paper charts (read north up) for so
long, it is natural for me. I have tied using my Maptech in course up and
found it disorienting

Fortunately North-up orientation is selectable regardless of chart style.

I had high brightness OceanPc displays in a pilot house environment, so
this was not a problem. It will be an issue in the new boat: no pilot
house.

Then going with an actual marine chartplotter will probably be better. If
not just for the display brightness but also for the purpose-intended
waterproof keys. No fiddling around with remembering what Function keys are
supposed to be doing...

While all of this has been available in the PC / Raster chart arena,
certainly not a cost that compares well with the integrated solutions
available with vector charts. This is a great feature and I look forward
to playing with it. I suspect this really requires the use of a gyro
compass to get a sufficiently stabilized overlay. I had a gyro on my last
boat and it made a big difference in ARPA accuracy.

Hmmm, dunno. I don't have my autopilot running most of the time (powered
off) and the MARPA features work great. And, iirc, there's not a gyro in
this one anyway. But then again I'm in a powerboat so gyro sensing is
probably less important.

I hope I have that whine out of my system so I can just get on with it...

Heh.

On Mon, 18 Sep 2006 13:49:01 -0400, "Gerald"
wrote:

I suspect this really requires the use of a gyro compass
to get a sufficiently stabilized overlay. I had a gyro on my last boat and
it made a big difference in ARPA accuracy.

Not really. I have an electronic compass sensor and it works just
fine for both ARPA and chart/radar overlay.

"Wayne.B" wrote in message
...
On Mon, 18 Sep 2006 13:49:01 -0400, "Gerald"
wrote:

I suspect this really requires the use of a gyro compass
to get a sufficiently stabilized overlay. I had a gyro on my last boat
and
it made a big difference in ARPA accuracy.

Not really. I have an electronic compass sensor and it works just
fine for both ARPA and chart/radar overlay.

Interesting. Actually, the Gyro was part of the KVH TracVision system.
Extra output port allowed it to interface with the radar. The Fluxgate I
had did not respond fast enough to keep up with rock'n and roll'n in any
kind of seas, the Gyro did much better. New boat will not have KVH so maybe
the electronic comass will do the job. Thanks for the input

Wayne.B wrote:
On Mon, 18 Sep 2006 11:56:53 -0400, "Bill Kearney"
wrote:


Since this feature
requires rotating and zooming the chart data to match the radar
display, vector charts are clearly the right choice.

Hmmm, no it doesn't. At least not on a Raymarine E-80. I can overlay radar
on top of charts in any orientation. I tend to prefer North up orientation,
but the admiral likes it to rotate with the heading. It's a snap to change
between them.


I agree that it is theoretically possible to rotate the radar image
instead of the chart image. In practice however, virtually everyone
is used to looking at radar images in "heading up" format.

I was taught, and always use north up. All of my peers also use north
up. That way the picture doesn't change every time you alter course or
make a small correction. It comes from the days of using parallel index
lines when navigating blind.

Gary

On Tue, 19 Sep 2006 04:15:38 GMT, Gary wrote:

I was taught, and always use north up. All of my peers also use north
up. That way the picture doesn't change every time you alter course or
make a small correction.

Are you talking about radar or charting ?