OpenCPN Version 5.1.518 Beta Test

[SCarns]

Thanks for this! First impressions on Mac OSX Catalina:

1) I don’t have to re-identify chart folders on start-up anymore. It wasn’t a real problem; more of an annoyance. Now that it works as it should: whoo hoo!!!

2) plug in manager is awesome.

3) chart downloaded is noticeably slower than in previous versions. Again, not a problem, as it works just fine. Just an observation.

4) very solid so far. I’ve loaded all my usual plugins and have no issues to date. Will run it side-by-side with O5 on this weekends trip to see how it holds up..

[transmitterdan]

Originally Posted by P_Dub

Gentleman, I am coming back again with that:- the possibility to adjust the scale to what ever you want. For instance say 1:15000 or else as desire. Presently you are zooming in or out to whatever happend. So, is it possible.
I would appreciate.

P_Dub,

I agree with you. It may not be in next release but it is something I have wanted for long time now. Just needed someone else to ask.

Note that in this beta you can adjust how much the zoom buttons adjust the zoom. It requires a manual edit of the opencpn.ini file. But it’s a new feature several have asked about. You may already know about it.

You can set the zoom jump factor to anything now. Normally it is 2 meaning zoom level moves in 2:1 jumps. If you set it to 1.5 or 1.25 then the zoom jumps are much smaller and it takes more zooms to make big zoom changes.

[bdbcat]

TDan....


I really want to make sure what you are asking for.
A 1:25000 chart scale, traditionally, means that you can use a scale (calibrated ruler) to make measurements on a printed chart.
On an ECS using quilted charts, like OCPN, what is the equivalent? I think we can agree that there is no scenario in which a normal use a user would lay a ruler against the computer screen, read a number, and calculate a true distance.


So, on OCPN, when you ask for a 1:25000 scale, what do you really mean?


I suspect you mean: "If there is a chart in the quilt whose native (paper) scale is 1:25,000, then make that chart the "reference chart", and show it at a "useful" scale.


But what is the "useful" scale? The entire paper-chart equivalent geographical area shown on-screen? If so, then I suggest you would find that the chart features too small to be useful. So then, half the geo area? or what?


And, of course, all of the above applies to familiar raster chart use. What about ENCs, that do not have an equivalent "paper scale"?



I know, I know, "Just do the right thing..." And we try.

Dave

[transmitterdan]

Dave,

What i mean is the small box lower right that displays scale I want to click it and a dialog box lets me type in the scale. Then the existing zoom function takes that new ratio and runs.

Let’s say it displays 51000 and I click and type 25000 then it should adjust the zoom by 0.4902. Nothing more exotic than that.

Why is this useful? Well, one thing is in dual display i could get both displays to the same scale. Today there is no way to do that.

[P_Dub]

Gentleman, you can adjust in the ini file with:- PlusMinusZoomfactor by changing the value from 2 to 1.5 or 1.25 but not to 1. What is necessary is to insert a small box in bottom right hand corner + - (number) to be able to adjust the scale of the charts (CM93 or S57 (S63 if so)) to what ever someone like. I suggest that to be exact number 1:10000; 1:15000; 1:20000; 1:30000; 1:50000, etc...
Am I clear enough. That is what is missing in Opencpn. You could make a list for choice and I am quite sure that many would like it.
Thank you for this great chart program and I am quite sure that this would be appreciated.
Best Regards.
P_Dub

[hoolie]

I'm puzzled because on my W10 laptop the zoom does not behave at all as described above. The .ini file has PlusMinusZoomFactor=2 as the default, but the +/- controls not only appear to have a factor of about 5 but the scales are not repeatable zooming up or down. Example:

1:63300 +
1:11700 -
1:61400 +
1:11300 -
1:58000

Of course in practice this is not very useful.

The +/- keys on the keyboard have zoom factor of about 1.2

ps It's just the same on my other Dell laptop running 5.0.0 so maybe it's a quirk of the venerable Intel graphics on the two devices?
My boat PC is much more recent but I don't have access to it yet ... ...

[P_Dub]

Hoolie, that is exactly the reason why it would be appreciated. It is not repeatable for the scale. Now, most of the charts are produce at an exact figure and not about like in the beginning of the 1900.

[hoolie]

bdbcat wrote:

What about ENCs, that do not have an equivalent "paper scale"?

As noted above the scales for ENC charts vary all over the place. I can't fathom where the displayed scales come from but surely it should be possible to "round them off" and make them zoom consistent? Personally I'm not bothered about being able to set a specific scale but I would like them to have some consistency when zooming in and out

[Moo]

I'm with the others on the chart scale quandary. In a single window it didn't matter too much with vector charts, but now that a split window has been introduced being able to select identical scales is at least convenient, if not important, with all charts.

[transmitterdan]

Originally Posted by P_Dub

Gentleman, you can adjust in the ini file with:- PlusMinusZoomfactor by changing the value from 2 to 1.5 or 1.25 but not to 1. What is necessary is to insert a small box in bottom right hand corner + - (number) to be able to adjust the scale of the charts (CM93 or S57 (S63 if so)) to what ever someone like. I suggest that to be exact number 1:10000; 1:15000; 1:20000; 1:30000; 1:50000, etc...
Am I clear enough. That is what is missing in Opencpn. You could make a list for choice and I am quite sure that many would like it.
Thank you for this great chart program and I am quite sure that this would be appreciated.
Best Regards.
P_Dub

P_Dub,

What you suggest is not simple I think. At any given moment multiple charts can be displayed and they all may have different scale factors. Doing what you suggest seems to make sense for a single chart display but when charts are quilted it gets too complicated I think.

Anyway, one should not rely too heavily on the scale factor shown because you can’t depend on the actual screen size. For paper charts scale is important. For electronic charts not so much.

[bdbcat]

Moo...


Finally, a reason that I understand.


" but now that a split window has been introduced being able to select identical scales is at least convenient, if not important, with all charts."


Thanks for the clarity.
Dave

[bdbcat]

re:
"Anyway, one should not rely too heavily on the scale factor shown because you can’t depend on the actual screen size."


FWIW, if the OS reports the screen physical size correctly, or has been set correctly in settings, then the scale factor shown is actually correct for the on-screen image. Hold a ruler/scale up to the screen and do the math, as an exercise.


Dave

[P_Dub]

All ecdisk and chart server that I have use in the pass, had chart scale like I said. So, it might be time to come up to that.
So long.

[bdbcat]

P_Dub...
"All ecdisk and chart server that I have use in the pass, had chart scale like I said."


I believe you.
And I claim that the value shown (e.g. 1:25000) on other software is very likely wrong, wrong, depending on the display connected.

We prefer not to show information that we know is incorrect. What we show in OCPN is provably correct, if sometimes inconvenient.


Dave
btw, You may notice that I am immune to pitchforks and firebrands...

[transmitterdan]

Originally Posted by bdbcat

re:
"Anyway, one should not rely too heavily on the scale factor shown because you can’t depend on the actual screen size."


FWIW, if the OS reports the screen physical size correctly, or has been set correctly in settings, then the scale factor shown is actually correct for the on-screen image. Hold a ruler/scale up to the screen and do the math, as an exercise.


Dave

Dave,

I agree with you. There are a minority of displays that get the pixels per mm wrong. This is especially true with HDMI displays out of China that don’t report to the video hardware correctly. It’s getting better but HDMI is kind of the Wild Wild West of video.

I think the point about being able to sync the two displays is my reason for wanting the ability to manually set the “scale”. Especially when using a plugin like oDraw or Radar. It might be nice to have a global flag that keeps the two displays in scale sync. If you zoom one the other automatically follows.