Manihi Atoll FP - First Landfall in the Tuamotus

Manihi Atoll Locator Map

Manihi Atoll - Landsat ETM+ Image S-06-10_2000 (1:110,000)

Manihi Atoll - EVS Precision Map (1-110,000)

Manihi Atoll is one of French Polynesia's premier destinations for the tourist wishing to view pearl farming first hand. According to the Tahiti Tourism North America, Manihi Atoll has over 60 working pearl farms. While one is looking for those perfect pearls, the Manihi Pearl Beach Lodge beckons. This atoll is one of the first landfalls for the visiting yatchsmen traveling from the Marquesas to Tahiti.

Manihi Atoll - Pacific-Image Map

In doing research for Manihi Atoll I came across the Pacific-Image map. As to names of the various motus, it is complete. As to cartographic quality, it looks like a map, it seems like a map, and it is a map, one designed for the tourist. If you are into high quality tourist maps of Pacific Islands, specifically the islands of French Polynesia, for only $237.60 you can purchase a CD loaded with 72 of these very attractive maps.

Manihi Atoll - Detail from Image Pacific Map

Manihi Atoll - EVS Precision Map - Detail Tairapa Pass and Paeua (1:30,000)

Although the Tahiti Pacific-Image maps are excellent for their purpose, I like mine better. Compared to the Tahiti Pacific-Image map, my EVS precision map of Manihi Atoll takes into account a wider variety of layers of information. In addition, my maps are vectors, whereas Tahiti Pacific-Image's maps are raster images.

As to the production of this map, it was not particularly difficult to digitize and ultimately create the island map. However, my very busy life caught up with me and what should have been a 10-hour project, took two weeks to complete. I have other island projects in the works, but they will be completed and posted at this much slower pace. Until then...

Enjoy!

Nisos Aegina GR - An Athen's Island Getaway.

Nisos Aegina - Locator Map

Nisos Aegina - Landsat N-35-34_2000 (1:85,000)

Nisos Aegina - EVS Precision Map (1-85,000)

Nisos Aegina is located only 17.5 kilometers from Athens. The island serves as both a "bedroom" community for Athenians and as a summer getaway for city dwellers. Many of the homes located on this island are second homes of Athenians. Wikipedia has an in-depth article about the island.

Let's talk about the map. I have spent in excess of 6-hours on this map. The challenge was in determining the layers and finding a good color scheme that is pleasant to look at, yet imparts accurate and meaningful information. I used my entire suite of mapping software to complete this project - 1) Global Mapper to create vector layers and identify lat/lon grids. 2) MS Paint to draw the lat/lon grid lines and finally 3) ImageForge to complete the labels and their placement on the map. I realize most decent mapping packages come with these features all included. I am a creature of habit and like my end products. So if it isn't broken, why fix it!

Enjoy!

Thoughts - Lukuga River - A Water Road into Africa's Heart of Darkness

Lukuga River - EVS Precision Map (1:1,122,800)

Lukuga River Composite - Each Image at scale 1:50,000

I remember spending long hours digitizing the many features on this river map. It is 290 kilometers in length and contains 989 river islands. When finished, I eagerly posted a few images of this grand river. I titled the post something about "the heart of darkness". The original Lukuga River post gets lots of views. I think it has to do with "the heart of darkness" label and less about the Lukuga River. Well, it hit me this evening. The reason the Lukuga River map doesn't get the respect it deserves is you the viewers have not seen the entire course of the river. So enjoy the slideshow entitled "Lukuga River - A Water Road into Africa's Heart of Darkness".

Thoughts - Bigger is Good, Smaller is Better

View Larger Map

Nisos Aegina - Landsat Island Image Mosaic N-34-35_2000 (1-125,000)

I am currently reworking my map of Nisos Aegina. It is a bedroom island outside of Athens, Greece. A nice little getaway when life becomes too hectic in the big city. But this isn't the reason for this post.

You know that I construct island maps using Landsat ETM+ mosaics as my base imagery. I have a Landsat ETM+ digital library of all of the world's shorelines. I use Global Mapper software to digitize, creating vectors from which i construct my island maps. This software handles the Landsat ETM+ mosaics with ease. I have invested over $500 in Global Mapper and do not regret a cent of it. The software does exactly what I want it to do and Mike, the boss and software guru, keeps making improvements. But this isn't the reason for this post either.

This post poses the age-old question "Is Bigger Better?" as it applies to the world of imagery.

In the world of Landsat derived island specific orthorectified imagery, bigger is not necessarily better. This is the world of imagery anywhere from multi-GB files to a few hundred MB files. These very large image files test the limits of most software packages. Often their formats, (i.e., MrSID) require special handling to open and work with. Since I primarily work with island imagery, I figured that if I were to cut out the ocean and save the island and it's surrounding reefs at a scale allowing me to work at increasing zoom ranges, I could create the same high quality maps from much smaller sized imagery.

First I fashioned a series of Greek island mosaics (see above image). These were followed by a series of Tuamotu Atoll images. I call my creations Landsat Island Image Mosaics (LIIM). Here are a couple of examples showing the zoom capabilities using the Nisos Aegina LIIM as base imagery.

NIsos Aegina - Detail Western Shore LIIM N-34-35_2000 (1-25,000)

Nisos Aegina - Detail Aegina Harbor LIIM N-34-35_2000 (1-12,500)

I typically digitize shorelines and certain land use features at scales between 1:25,000 to 1:12,500. I know that this pushes far beyond the intended limits of Landsat-7, 14.5 meter resolution imagery. I have digitized at these limits for over four years. The resulting maps have a level of quality and precision that exceeds most widely available island mapping. My island maps have been used by a number of universities to further research and as a platform for spatial analysis by insurance companies.

The size advantage with these considerably smaller island images is significant. My LIIMs range in size from 2 MBs up to 45 MBs for very large islands. All of my LIIMs are saved as georectified JPGs. Nisos Aegina LIIM is 3.47 MBs and is a 15.8 MB Tif file. The Landsat image containing this LIIM, on the other hand, is 106 MBs. The image degradation is slight and barely noticeable. So, I will keep using my LIIM of a specific island from which to create my island maps. If you would like to use one of my LIIMs, drop me a line. I'll fix you up.

Enjoy!