Raster vs. Vector charts, our take on the debate

This question might possibly be more interesting for those who are just diving into the world of navigation. However, as things stand, this article could also be helpful to anyone passionate about the sea. To begin with, there is a real debate going on between these two schools, yet it’s tough to say which nautical chart format is better than the other, as the choice depends most of the time on user habits or personal preference.

Aim solving this question might be a lost battle as it might not apply equally to everyone. However, here we want to give you a quick overview of the key characteristics that define each type of chart and an additional expert opinion on the topic by Leon Schulz, Yachtmaster Ocean Instructor, and long-time TIMEZERO user.

Let’s begin with the Raster Charts

Raster Charts are an exact reproduction of the traditional nautical paper charts, as they are digital scans of printed lithographic charts. What is the great thing about Raster Charts? Users that have always used nautical paper charts are more than happy and reassured to find the same information on the screen.

Vector Charts

On the other hand, Vector Charts are a rendering of a lithographic chart in a point-by-point format. “Vector” is a synonym for line, and vector charts are composed of mathematically defined geometric shapes: lines, objects, and fills. Think of connecting the dots; that is the same principle. These dots are stored in a database and drawn on the computer or plotter screen by the software. Therefore, the display of a Vector Chart doesn’t look much like a nautical paper chart.

What is the great thing about Vector Charts? You have more displaying options, and they require less space on your hard disk.

This comparison graph, created by our expert Leon Schulz could give you a better view of the pros and minuses of each type of chart. Also, it might allow you to see which one might be more suitable for you, or as Leon does, combine both type of charts and get the benefits each has to offer.

Vector Charts

ProsMinus
Easy to update due to smaller file sizeWhen a layer is off, you might miss important information
Modern and clean presentationFont size is always the same, might be problematic for small screens
Possible to switch on and off various layers to get only relevant informationCan easily loose overview of scale, since all zoom levels look alike
Continuous step-less zoomingLand information is often scarce
Can switch on alarm functions (e.g., an alarm when a route leads over shallow parts)From certain zoom levels some information such as text disappears
What it’s shown in certain zoom level depends on the provider and screen size
 If you need information about a buoy or lighthouse, you need to click and scroll down on a specific window

Raster Charts

ProsMinus
Looks like paper chart, which is familiarZooming in steps: one chart is enlarged until suddenly it jumps into the next scale
Font size gets bigger when zoomingSpecific information cannot be switch on and off
More information about the shore: churches, beaches, streets, etc.A computer cannot interpret the picture, therefore no alarm functions available
Easier to judge distance by eye, since scale is clearly defined 
Thanks to manual production, smart choice, and placement of information 
Information about buoys and lighthouses placed directly next to the object 

Moreover, see this short video to get our expert’s opinion on the topic. 

Also, keep in mind that in general, Raster Charts are made by national hydrographic services and Vector Charts by private companies. Neither type of format exists for all the world regions, so the accuracy and richness of data will depend on your area. 

And lastly, in the TIMEZERO team, we understand that accurate charts mean safety at sea. For this reason, all our charts are updated at least once a year. Check in this link all the charts available.