31 August 2014

How to create a raster chart for the Magellan Explorist GPS

Raster charts are the best of both worlds. You can get the most accurate graphic description of the Earth's surface existing today - in the form of topographic charts - adapted to be read by the modern portable GPS on the market.
Certainly today we have also the Vector charts. And these are, probably the future in digital cartography. These are digital files made from scratch and presented in the GPS display just like that. I mean: you don't have a paper look-a-like image. Instead, what you have is a digital rendition of the terrain. This is, certainly, the future. You can control the information you want to see, therefore avoid crowding the GPS displays with too much or excessive information. For example, and since these modern charts work by "layers", you can clear, momentarily, the exhibition of roads, or cities, or man-made constructions such as power lines, etc., thus giving a clearer presentation of the natural features of the ground. As good as they are, these charts (normally bought in digital folios - packages of charts of a specific Earth region) are not cheap. Quite often just a single folio (for example: Northwestern Africa or US West National Parks) can cost as much as the GPS receiver itself. And you still have to face the cost of the cartography updates, if you wish to be... updated.
So, if you have a folio of old topographic paper charts at home, its easily understandable that you might wanna use them on your portable GPS receiver. After all, even if they are outdated, they still remain accurate. Changes in topography are mostly of human nature. Th natural world, except some abnormal catastrophe, remains the same. Therefore, there is absolutely no reason not to use your accurate topographic charts on your GPS unit. Even if they are twenty years old. Hell, here in Madeira I'm working with Portuguese Army topographic charts, in a scale of 1/25.000, which survey was made in the late fifties and sixties. If they are good for the Army, they certainly are good for me.
How do we do this? The magical conversion from an accurate paper topographic chart to a similarly accurate digital topographic file?
Well, it ended up to be easier than expected. I'm no expert, but here is how I did it:

1. Scan your paper chart (or part of it) in a flatbed scanner and save the resulting file (picture) in .jpeg or .png format. Strangely I've found the jpegs files not color accurate on the GPS. The files in this format always shown a strong magenta cast and the colors of the original chart are lost on the GPS, giving us a monochromatic image in magenta. The .png files seem to work OK.
2. Download this file onto the free program RMP Maker and calibrate it, using for that a minimum of three geographic positions, widely separated on the picture. Don't forget that the chart datum of the chart must be the same you are using for the calibration process. Otherwise, you'll always have a positioning error, up to several hundreds of meters. Nowadays almost all the topographic charts are referred to the WGS 84. But many of the old charts are not. Create one .rmp file, already calibrated on the above-mentioned program. Now, if you have a Magellan Triton GPS receiver, at this stage you just have to export this file to the GPS and it should work faultlessly. But if you have one of the latest Explorist family, and since these equipments use different file formats, you have one additional step to make. Convert the .rmp file in a file readable by the Explorist:
3. Convert the .rmp calibrated file into a bak.rmp file (readable by the Explorist) in the free program RMP Tools.
4. Download the resulting file directly to the Explorist Maps Folder, by USB cable connection, either going directly by Windows Explorer to its directory or using the free Magellan software VantagePoint. It should work perfectly, as you can see on my previous post, about the Magellan Explorist 610.

Once again, I tell you that I'm no expert in the field, but I've found the process quite manageable, even for an ignorant like me. All the software mentioned is intuitive, and you can easily get the grip of it in just a couple of hours.The most important part of the process being the digital chart (file) calibration. If this is done right, you'll have an accurate raster chart on your Magellan Explorist. Good luck. 

29 August 2014

My first AI lens

As many photography lovers, I would never give up film photography if it wasn't for the slow decline of the support system behind us.
Nearly ten years ago, when I shifted from a seafaring career to a more terrestrial one, I still could find a laboratory in Funchal able to process positive films. A couple of years later, with just a handful of last clients, they were forced to close the service and, consequently I, too, reluctantly, migrated to digital, with my first acquisition in the field: a Nikon D40X and its standard Nikkor 18-55mm AF-S zoom.
And I emphasize "reluctantly" because, back then, I knew I was opening a Pandora's Box full of superfluous things, many of them not truly indispensable for our photographic endeavours. Menus, auto-ISO's, VR's, autofocus I, II and III and so on, were designed to make our life easier in the field. To make picture taking simpler and intuitive.
On the contrary, and most of the times, these modernisms, as Ken Rockwell wisely pointed out, gives us more chances to loose a photo opportunity than to achieve one.
On those frustrating moments, I wish for simpler techniques and equipment. Anything that returns to us the simplicity of the photographic act.
Nikkor AI lenses mean just that: simplicity and effectiveness. Just an optical tube with both manual focus and diaphragm rings. It just doesn't get any simpler.
Understandably, and since all these lenses were designed in the film age, you have to be smart while buying a modern digital body fully compatible with their manual iris selector.
But even if you own the simplest of the Nikon digital bodies, these lenses remain perfectly usable. You just have to guess the exposure or do it by trial and error.
After all, it's the digital age. What do you have to loose? Card space?
And have I told you that they are really cheap, bought second-hand, on E-Bay, these days?
The notable Japan-made Nikon Nikkor 50mm f/1.4 AI, bought second-hand on E-Bay, from the competent Japanese seller AIHALAND-JP. 110 Euros of solid metal and glass, as Ken Rockwell wisely points out, "...built like a tank for a lifetime of great pictures.".
The quality on the details is simply amazing. Reminiscent of an era when handcrafting perfectionism was a standard industrial procedure. Note the detailed depth-of-field scale, painted with the same colours of the numbers on the diaphragm scale. Small red dot for Infra-Red focus correction also present.
The aft part of the lens, showing its bayonet mount and the diaphragm activating lever. 257 grams (naked) of solid construction with, in my modest opinion, just one drawback: a minimum focus distance of 0.45 mts. But, anyway, this was normal for a 50mm lens of that era. If you want to focus closer, you might prefer one of the fabulous - according to many reviews - Micro-Nikkors 55mm f/2.8. You'll loose speed, however.
Nikkor 50mm f/1.4 AI focused at minimum distance at f/2.0. No so bad bokeh, don't you agree? Shot with a Nikon D610.
In hyperfocal focus, from foreground to background, in the distant horizon. Shot at f/8 with a Nikon D610. Sharpness all over, so it seems. Notice the tree branches?

20 August 2014

GPS Magellan Explorist 610 - A quick review

While navigating (regardless of being in the wilderness or on your own neighbourhood), you permanently need to answer to three questions; where you are, where you want to be and how to get there. The first and second questions are normally answered by a geographical position (either a Lat/Long pair of coordinates or a location, for example: Lisbon), whereas the latter can only be answered by a combined use of resources and science known by us as navigation.
Contrary to the common knowledge, the GPS is a not a navigation system. It's a positioning system. The name (GPS - Global Positioning System) clearly implies it. It was built and devised with the ambition of being the (near) perfect system to plot the position of its user anywhere on the globe, with the greatest accuracy that the modern human knowledge allows. It is, therefore, the successor of the sextant and the nautical tables and of the Decca and the Loran electronic positioning systems. It was never designed as an orienting system. For that job, to tell you how to go from the departure position to the arrival position - in a word: to give you the travel direction, you still need an orienting equipment. And this can be as simple as the common magnetic needle or as sophisticated as the modern gyrocompass. Let's face it: if all you ever needed for navigation was a 400 Euros GPS, why are all the ships worldwide equipped with gyros and gyro-pilots that can cost more than one hundred times that amount?
Regardless of that, GPS technology evolved a lot on the past twenty years. From the ancient bulky, professional, fixed and power-hungry receptors costing a small fortune we reached now the frontiers of portability, with these equipment's reaching the size of a wristwatch.
With the miniaturization came also the expansion of capabilities. Thirty years ago, the ancient GPS's only gave you a geographical coordinate. Nothing more. You'd have to plot the information on the nautical chart to perform your navigation calculations. Nowadays, a GPS receptor is a more complex machine, allowing you to elaborate tracks and courses and it is becoming more and more (with limitations) a navigation-do-it-all computer.
Since the system is fully functional either over land, sea or air, it was a matter of time for it to be used on outdoor activities.
Somehow curious how this type of equipment would help my mountain activities, I took the plunge and decided to buy one of them.
From the various makers on the market - Garmin, Lowrance, Trimble, Magellan, to name just a few - I choose the Magellan. Primarily for the noble name of it. In second for its technical characteristics, and in third for its already included worldwide coverage map and topographic charts (Summit series) for Europe.
As in everything in life, nothing is totally perfect. And this GPS equipment, although competent, is far from it.
Here's my two cents worth on the matter.
The GPS Magellan Explorist 610, with its navigation screen on Course-Up mode. A competent equipment, loaded with features. This equipment is, somehow, positioned, in characteristics, between the Garmin Oregon 450 and the Oregon 550, its direct competitors. Relevant features include:

Display: 3" Resistive Touch Screen colour display with 240x400 resolution
Altimeter: Barometric and/or GPS altimeter
Camera: 3.2 mega-pixel camera with auto-focus (capable of geotagging photos)
Video: 320x240 resolution size
Audio: Built-in microphone and speaker (capable of recording voice notes)
Compass: 3- axis electronic compass
Waterproof: Rated to IPX7 standards (immersed in up to 1 meter of water for 30 minutes)
Accuracy: 10-16 feet
Interface: mini D to USB

A detailed and competent review is also available on the site BackCountrySkiingCanada.
The back of the equipment, showing its camera lens, the speaker and the belt hook and the back panel lock - both made of solid stainless steel. The USB connector (protected by a waterproof cover)  is located near the palm of my hand, near the plastic loop. Regardless of the so-called waterproofness, I have to be honest with you: I'd be very careful with any attempt to sink the equipment in water to its IPX7 standards - waterproofness up to 30 minutes in 1 meter depth. The O-rings on the equipment don't give me that confidence, particularly the USB connector. Having tested the equipment in heavy rain though, I can vow for its resistance to rain showers and wet conditions. Which is, basically, what we need it for.
A side view of the equipment, showing its three control buttons. All of them allow for some function customization which is, in my opinion, a plus. GPS receivers are supposed to be operated with an alphanumeric keyboard, particularly on its major functions, like saving a waypoint. Going through menus to do this simply isn't practical. This is one step ahead from the nearest competitors.
The front of the equipment, showing its microphone (useful for voice notes on the trail). You might ask yourself why the need for this. Well, honestly, since you have it... it's never too much. After all, all the professional Nikon camera bodies of the last decade (D3, D3S, D4, D4S) have also this kind of gizmo. It's useful for photographers in the field. To record some voice memos about pictures and places, they say. Well, you have the same ability on your Magellan Explorist 610. The chart shown on the screen is a Raster chart of the Pico Ruívo area. It's basically a digitalization of a Portuguese Army topographic chart, on a scale of 1/25.000, geo-referenced, and transformed in a digital file, readable by the Magellan GPS. With this ability, we get the best of both worlds: the precision and graphical perfectionism of a paper chart and the ability to use it on a digital equipment.

What I like about it:
- Robust plastic, metal and rubber carcass.
- Customizable buttons.
- Good computer software: VantagePoint (there's still place for improvement, though).
- Plenty of accessories on the market, even from third-parties: 12 volts car connectors, bicycle, car and motorbike supports, etc.
- Bright display with recessed screen, giving additional protection to impacts.
- Excellent "Suspend" mode, allowing for extra duration of batteries, while keeping GPS fix and tracking.
- Waterproofness.
- Acceptability of Raster and Vector charts, either topographic and maritime (the latter due to a Magellan partnership with Navionics, a worldwide respected leader on electronic charts and navigation).
- Good accuracy, up to 5 or 6 meters on the ground. In my modest opinion, it's more than enough. Anything more, and you are entering on Differential GPS universe. Do you really need this improvement of precision in detriment of more useful functions?
- Integrated loop, allowing to suspend the equipment by a carabiner or a piece of rope to the backpack. You either like it or hate it. In my opinion, it's useful.
- The included cartography.
- Availability of free cartography on the web, particularly on the site Maps4me.net.
- Integrated photographic camera, with workable definition, allowing also video shots. It's not 4K, but suffices for a geo-tagged photo or video clip.

What should be improved:
- Lame software. The equipment is not intuitive to operate and I find myself quite often reaching for the manual, to remember a procedure, even after months of frequent use. The menus, although extensive, are not coherent. There's lots of information, but lacking organization.
- Very weak manual. Some functions of the equipment are not clearly described and some icons appearing on the display are not even mentioned, leaving us to guess their meaning. Not good. Not a professional behaviour from a company that gave so much to the GPS technology. It leaves us with the impression that the equipment was designed in the States, built somewhere else and the manual, additionally, on another place. And all that with lacks in communication.
- No turn-by-turn tracking and routeing in nature (my friend's Garmin Oregon does this by default). Since on Terra firma (contrary to sea navigation) we rarely navigate in a straight line - the only exception, in some tracks and routes, being the deserts - the lacking of this function is not understandable.
- The autonomy of 16 hours in optimal conditions is... optimistic, to say the least. Half of that, with a fresh pair of alkalines is closer to the truth. With normal trail use, with frequent operation of the equipment, you can expect a maximum of three to four hours of use. If the ambient temperatures are low... well... good luck. Do yourself a favour and carry a couple of pairs of freshly recharged Ni-MH cells, even if you are just contemplating a single day hike. Truth being said, the competition doesn't seem to be better.
- Time to first fix. Poor. I've read some reviews saying this equipment is fast. It's not my experience. The processor seems to be slow and even with the latest firmware available (ver. 7.14), the equipment takes a minimum of 30 seconds to boot and an additional 30 seconds for the first fix. My friend's Garmin is almost instantaneous.

Bearing the name of the greatest navigator of them all is not an automatic receipt for success. There's a lot more work to be done by Magellan, if they wish to achieve a leading position in the consumer GPS market.

04 August 2014

Summer spirit

As the Summer advances, the religious festivities multiply all over Madeira. These fairs and festivals, peaking during the month of August, are normally organized by the municipalities' parishes as an homage to their patron saint.
In the end, more than a religious experience, these events end up being great social meetings, gathering not only the locals but also the tourists and the emigrants of the Madeira diaspora, who return to their homeland to review family and friends.
Among the biggest, the Arraial dos Lameiros, in São Vicente, during the first weekend of August, is, probably, the most loved one.
Thousands of people in the streets, religious ceremonies in a beautifully decorated chapel, music, party, food and the typical "poncha" within one of the most enchanted natural and human landscapes of Madeira.
Picture taken last Saturday night in Lameiros, North coast, with Nikon Coolpix P7100 and Sirui T005 tripod and ball head. Post-processing in Nikon Capture NX-D and Adobe Photoshop Lightroom.