The Plot Parameters dialog allows you to adjust various plotting options. You can use the Options -> Plot Parameters... menu item or speed button to open this dialog any time you have an active plot on the screen. The box at the top of the dialog gives the minimum and maximum value of the plotted data. The options you can change to tweak your plot are summarized below. (The program works to make the various values concur with each other; for instance increases in depth ranges will occur in increments of the chosen contour interval.) Note: The Hydro-Plot Legend (to the right of the dialog) will immediately show changes you make to the Plot Parameters.
Contour Interval: This is the value which determines the range of sounding (or other) values for the color bands. The program will attempt to assign a reasonable value (Default), but you may want to adjust this value to fit the data values in your plot (see Set Contours Button below).
Range of Legend Colors: When a new data file is opened, Hydro-Plot will determine the minimum and maximum values of the data. These values are used to determine the Start and End values of the Legend colorbar. You can change these Start and End values to change how colors are rendered from the data values. Use Set Contours Button (see below) to have the program determine reasonable values. (Changing these values may especially be needed when you Zoom-In).)
Plot Hydro Features (or Show NaN or Land Cells): For NOS Hydrographic Surveys data, you can choose to plot the Hydrographic Features. For gridded data you can plot the NaN (empty grid cell value) grid cells, which represent areas of no data in that cell. The plotted Feature/NaN point will be in the form of a black cross. (For NGDC's density grids NaN represents land grid cells.)
Plotted Data Value Size: Use this to determine the plotted size, in pixels, of the sounding or other value on your plot. Especially when zooming in, increasing the size of each plotted value can make it easier to see the individual values. When zooming in and increasing this value, be sure to reset it to a small size before you zoom back out, or the resulting plot will take a lot of time to render, as it will have to plot the increased number of pixels for each and every value.
Legend Colors:
Color Scheme:
11 Basic Colors If your video supports 256 or fewer colors you must choose the 11 Basic Colors option. You can remedy this by increasing your color depth of your monitor. In Windows 95 simply right-click on your screen background, then click Properties -> Settings -> Color palette -> High Color (16 bit) -> OK. If the High Color option is not available you should consider increasing your Video RAM.
Shades of Blue Choose this option when all values are depths (no land values). Use the Start Hue and End Hue scroll bars to set the starting and ending shades of blue, from light to dark.
Land/Sea Split When Land/Sea Split is chosen, there will appear a control for determining the land/sea contour, i.e. the contour value at the color break between land (all colors) and water (blues). The Start Hue and End Hue scroll bars determine the starting and ending hue of the land (color wheel) contours and have no effect on the sea (blue) contours.
All Colors. All the colors in the spectrum can be rendered by choosing this option. Use the Start Hue and End Hue scroll bars to determine the starting and ending hue of the contours.
You can manipulate how the color options are rendered by manipulating the Hue, Saturation and Luminance controls below.
Start and End Hue:
You may change the starting and ending hue of either the Shades of Blue or All Colors options by using the 2 scrollbars or entering the values directly. The hue value is based on a 360 degree color wheel which covers the color spectrum of all the colors, or just the range of blues.
Saturation:
Only used for All Colors option. Saturation is the intensity of the colors displayed. Select a value from 0 to 100 Percent.
Luminance:
Only used for All Colors option. Luminance is the brightness of the colors displayed. Select a value from 0 to 100 Percent.
Defaults Button Use this button to re-set all the plot parameters according to the defaults of the current plotted data. Items re-set include the Contour Interval and Range of Legend Colors (see above), Plot Hydro Features (or Show NaN or Land Cells), Plotted Data Value Size and Legend Colors.
Set Contours Button: Use this button in order to set only the contours for the current plotted data. Items reset are the Contour Interval and Range of Legend Colors. Note that when you change the data being plotted (by zooming, etc.), the minimum and maximum values of the current plot change. Clicking this button sets the contour parameters to optimum values based on these minimum and maximum values.