requires node.js scraper, very experimental, gives you http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/ as JSON

EXIF makernotes to JSON

// http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/Canon.html#CameraInfo5DmkII

var vendorToJSON = 'Nikon';

var scraper = require('scraper');
var util = require('util');
scraper('http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/'+vendorToJSON+'Custom.html', function(err, jQuery) {
    if (err) {throw err}
	var h2 = [];
	var ta = [];
    jQuery('h2').each(function() {
        h2.push(jQuery(this).text().trim());
    });
	jQuery('blockquote table.inner').each(function() {
        ta.push({table:this, name:'', fields:{}});
    });
	//var map = {};
	ta.forEach(function(t,i){
		ta[i].name = h2[i];
		
		var trs = jQuery('tr', t.table);
		trs.each(function(j,tr) {
			if(j>0){ 
				var tds = jQuery('td', tr);
				
				if(tds.length==4){
					var val = '';
					var str = (tds[3].textContent.trim().substr(0,1)=='[' && tds[3].textContent.trim().indexOf(']')>-1) ? tds[3].textContent.split(']')[1].trim() : tds[3].textContent.trim();
					var vStr = tds[1].textContent.trim();
					
					if(str.indexOf(' = ')>-1){
						// '0 = Off,  1 = On (1),  2 = On (2)'
						var vals = str.replace(/\n/g, '",').replace(/ = /g,':"');
						val = { name:vStr, val:'{'+vals+'"}' }
						vals = null;
					} else if(str.indexOf('-->')>-1){
						val = { ref:str.replace(/-->/g, "") };
					} else {
						val = vStr.replace(/\n/g, ",");
					}
					
					ta[i].fields[tds[0].textContent] = val;
					
					val,str,vStr = null;
				}
				tds = null;
			}
			
		});
		trs,ta[i].table = null;
		delete ta[i].table;
	});
	var tmpTa = ta;
	var ta = {};
	tmpTa.forEach(function(t,i){
		var n = t.name;
		delete t.name;
		ta[n] = t; 	
	})
	console.log(util.inspect(ta, false, null));
	// ta is our OBJECT! Do something with ta. E.g. write to file ...
});