+Ernmark Posted July 17, 2007 Share Posted July 17, 2007 I hate to see the NGS thread go dormant for too long, so here's one - I was nosing around on monkyekat's BM viewer & ran across HU1512 HU1512 *********************************************************************** HU1512 DESIGNATION - OCEAN CITY HOUSE 1 CHIMNEY HU1512 PID - HU1512 HU1512 STATE/COUNTY- MD/WORCESTER HU1512 USGS QUAD - OCEAN CITY (1972) HU1512 HU1512 *CURRENT SURVEY CONTROL HU1512 ___________________________________________________________________ HU1512* NAD 83(1991)- 38 21 54.49197(N) 075 04 18.59934(W) ADJUSTED HU1512* NAVD 88 - HU1512 ___________________________________________________________________ HU1512 LAPLACE CORR- -0.30 (seconds) DEFLEC99 HU1512 GEOID HEIGHT- -35.98 (meters) GEOID03 HU1512 HU1512 HORZ ORDER - THIRD HU1512 HU1512.The horizontal coordinates were established by classical geodetic methods HU1512.and adjusted by the National Geodetic Survey in January 1992. HU1512 HU1512 HU1512.The Laplace correction was computed from DEFLEC99 derived deflections. HU1512 HU1512.The geoid height was determined by GEOID03. HU1512 HU1512; North East Units Scale Factor Converg. HU1512;SPC MD - 79,312.714 568,498.155 MT 0.99998931 +1 12 36.7 HU1512;SPC MD - 260,211.80 1,865,147.70 sFT 0.99998931 +1 12 36.7 HU1512;SPC DE - 40,586.231 230,136.678 MT 1.00000618 +0 12 50.5 HU1512;SPC DE - 133,156.66 755,040.08 sFT 1.00000618 +0 12 50.5 HU1512;UTM 18 - 4,246,331.395 493,724.640 MT 0.99960048 -0 02 40.5 HU1512 HU1512 SUPERSEDED SURVEY CONTROL HU1512 HU1512 NAD 83(1986)- 38 21 54.47357(N) 075 04 18.62692(W) AD( ) 4 HU1512 NAD 27 - 38 21 54.05663(N) 075 04 19.97442(W) AD( ) 3 HU1512 HU1512.Superseded values are not recommended for survey control. HU1512.NGS no longer adjusts projects to the NAD 27 or NGVD 29 datums. HU1512.See file dsdata.txt to determine how the superseded data were derived. HU1512 HU1512_U.S. NATIONAL GRID SPATIAL ADDRESS: 18SVH9372546331(NAD 83) HU1512_MARKER: 85 = CHIMNEY HU1512 HU1512 HISTORY - Date Condition Report By HU1512 HISTORY - 20031228 FIRST OBSERVED USPSQD HU1512 HU1512 STATION DESCRIPTION HU1512 HU1512'DESCRIBED BY US POWER SQUADRON 2003 (JW) HU1512'MARK NOT FOUND. 1) It, if first observed in 2003, is, of course, too new to be in the CG database (GC won't even display the usual "no-PID" page [server Error in '/' Application. ParseSheetException: locHistory too small! ]), but the PID is in an older range - nearby PIDS date to the 30's. 2) It is an intersection station. 3) I was never described. 4) ...and then there's the USPSQD component ! What do you make of this? It looks to me like it may have been in the DB for years & unobserved until JW ran across HU1512 in the database in 2003.... Quote Link to comment
+Harry Dolphin Posted July 17, 2007 Share Posted July 17, 2007 (edited) Not too surprising. A lot of chimneys were monumented, but never logged into NGS. Example: KV4204 *********************************************************************** KV4204 DESIGNATION - LIGHT CHIMNEY KV4204 PID - KV4204 KV4204 STATE/COUNTY- NJ/ESSEX KV4204 USGS QUAD - ORANGE (1981) KV4204 KV4204 *CURRENT SURVEY CONTROL KV4204 ___________________________________________________________________ KV4204* NAD 83(1996)- 40 46 41.30034(N) 074 09 05.62579(W) ADJUSTED KV4204* NAVD 88 - KV4204 ___________________________________________________________________ KV4204 LAPLACE CORR- 6.02 (seconds) DEFLEC99 KV4204 GEOID HEIGHT- -32.22 (meters) GEOID03 KV4204 KV4204 HORZ ORDER - THIRD KV4204 KV4204.The horizontal coordinates were established by classical geodetic methods KV4204.and adjusted by the National Geodetic Survey in September 1999. KV4204 KV4204 KV4204.The Laplace correction was computed from DEFLEC99 derived deflections. KV4204 KV4204.The geoid height was determined by GEOID03. KV4204 KV4204; North East Units Scale Factor Converg. KV4204;SPC NJ - 215,970.381 179,411.001 MT 0.99991064 +0 13 39.3 KV4204;SPC NJ - 708,562.82 588,617.59 sFT 0.99991064 +0 13 39.3 KV4204;SPC NY L - 67,912.673 287,205.641 MT 0.99999569 -0 05 56.9 KV4204;SPC NY L - 222,810.16 942,273.84 sFT 0.99999569 -0 05 56.9 KV4204;UTM 18 - 4,514,475.087 571,593.992 MT 0.99966309 +0 33 15.0 KV4204 KV4204 SUPERSEDED SURVEY CONTROL KV4204 KV4204 NAD 83(1996)- 40 46 41.30010(N) 074 09 05.62606(W) AD( ) 4 KV4204 NAD 83(1986)- 40 46 41.29594(N) 074 09 05.63198(W) AD( ) 4 KV4204 NAD 27 - 40 46 40.93000(N) 074 09 07.12000(W) AD( ) 3 KV4204 KV4204.Superseded values are not recommended for survey control. KV4204.NGS no longer adjusts projects to the NAD 27 or NGVD 29 datums. KV4204.See file dsdata.txt to determine how the superseded data were derived. KV4204 KV4204_U.S. NATIONAL GRID SPATIAL ADDRESS: 18TWL7159414475(NAD 83) KV4204_MARKER: 85 = CHIMNEY KV4204 KV4204 HISTORY - Date Condition Report By KV4204 HISTORY - 1913 FIRST OBSERVED CGS KV4204 HISTORY - 20051113 GOOD GEOCAC KV4204 KV4204 STATION DESCRIPTION KV4204 KV4204'DESCRIBED BY GEOCACHING 2005 (PR) KV4204'FOUND BY COORDINATES. THE SURROUNDING BUILDINGS ARE DECREPIT, BUT THE KV4204'CHIMNEY IS STILL THERE. ON THE EAST SIDE OF MCCARTER HIGHWAY, IN KV4204'NEWARK, NEW JERSEY, JUST NORTH OF THE RAILROAD BRIDGE. I found it 92 years after it was first (and for the only time) reported. Nope, not much of a description. But, at least CGS did report it. (Think I needed a chimney for one of John and Shirley's contests. ) As to USPSQD... They have been known to do drive-by DNFs. (Then again, so has NJGS.) I don't take a DNF from either source as proof of anything. (The same goes for geocachers who do not include photos...) Google Earth is not too clear, but there does look like there might be a chimney at the location in Ocean City. Edited July 17, 2007 by Harry Dolphin Quote Link to comment
+Ernmark Posted July 18, 2007 Author Share Posted July 18, 2007 ..I checked out Google Earth also - this area is full of relatively new buildings. I'll add a field observation of this location on my next visit. I'm most perplexed by this line: HU1512 HISTORY - 20031228 FIRST OBSERVED USPSQD PS - I like your description for KV4204 - <THE SURROUNDING BUILDINGS ARE DECREPIT> Quote Link to comment
+PFF Posted July 18, 2007 Share Posted July 18, 2007 (edited) The 2005 logs for KV4204 are excellent. Glad to know it's still there! Here is an aerial photo which I downloaded from TopoZone. This photo has been cropped and resized for the Forum. However, the original scale is 1:3000, and the detail is extremely good. Note the shadow pointing toward the northwest. Even without the time stamp, you can determine that this picture was taken around 10AM on a winter day. -Paul- Edited July 18, 2007 by PFF Quote Link to comment
edmcnierney Posted July 18, 2007 Share Posted July 18, 2007 However, the original scale is 1:3000, and the detail is extremely good. Note the shadow pointing toward the northwest. Even without the time stamp, you can determine that this picture was taken around 10AM on a winter day. According to the USGS, the original scale is 1:2,400 (your posted copy is a little lower resolution than the original, where it's easy to see that the chimney is round). They don't label each individual photo, but all the photos in this set are reported to be taken between 2/18/2002 and 4/11/2002. Quote Link to comment
+PFF Posted July 19, 2007 Share Posted July 19, 2007 (edited) However, the original scale is 1:3000, and the detail is extremely good. Note the shadow pointing toward the northwest. Even without the time stamp, you can determine that this picture was taken around 10AM on a winter day. According to the USGS, the original scale is 1:2,400 (your posted copy is a little lower resolution than the original, where it's easy to see that the chimney is round). They don't label each individual photo, but all the photos in this set are reported to be taken between 2/18/2002 and 4/11/2002. Hi, edmcnierney, The vendor listed the resolution as 1:2952, or 1ft/pixel. However, I'll be the first to admit that I don't understand all the technical details regarding the scale of aerial photography. I simply pay my $50/year and download whatever photos I need. [Grin.] The following spec's accompanied the photo I posted: USGS High-Resolution Urban Area Photography Info These USGS High-Resolution Urban Area photos are available to TopoZone Pro subscribers for viewing, and can be used to create PhotoFactory custom downloadable aerial photo images. Use this information to check for dates and availability of high-resolution photography if you are considering one of those subscriptions. UA Filename: new_jersey/j6b16.tif UA Dataset: new_jersey Band Type: CIR Resolution: 0.3048 meters Photo Date: December, 2002 Edited July 19, 2007 by PFF Quote Link to comment
edmcnierney Posted July 19, 2007 Share Posted July 19, 2007 The vendor listed the resolution as 1:2952, or 1ft/pixel. However, I'll be the first to admit that I don't understand all the technical details regarding the scale of aerial photography. I simply pay my $50/year and download whatever photos I need. [Grin.] Ah, scale ratios - the bane of the digital world! The original film (where the scale ratio DOES make sense) was reported by the USGS subcontractor to be 1:2,400, meaning that one inch of film contained a picture covering 200 feet on the ground. After that, things get muddy <g>. The film was scanned at a resolution of 200 pixels per inch, so each pixel represented one foot (0.3048 meters) on the ground. The best way to describe that image resolution is really to say "one foot per pixel". But we've learned that users REALLY like scale ratios, especially those trained to look for 1:24,000 scale maps. If I say that that photo is at 1:2,952 I'm saying that one inch on your screen represents 2,952 inches on the ground. But I can't possibly know how many pixels go into one inch on your screen, and if I claim I do know you'll reach over and tweak the horiztonal size knob and make me wrong again! We started with the conventional fiction, back in 1999, of pretending that the user's screen or printer had a resolution of 250 DPI. That might be true of your printer, but it's almost certainly not true of your screen (anywhere from 96 DPI to 125 DPI is more likely). We did that because the original USGS DRGs were scanned at 250 DPI. If you selected a View Scale setting of "1:24,000" and you were viewing a 1:24,000 scale DRG, you would be seeing a pixel-for-pixel identical copy of the original image, and that was considered a Good Thing. Since then we've continued that fiction (as do many other map viewers, both online and in desktop software). A scale ratio makes no sense unless you know or state the resolution of the output device in pixels per inch. IF your output device is 250 DPI, and you are viewing at a scale of 1:2,952, then one inch on the screen equals 2952/250 = 12 inches or one foot on the ground. The astute reader will note that that math is not quite correct, and a scale of 1:3,000 should be 1 inch = 1 foot at 250 DPI since 12 * 250 is 3,000 rather than 2,952. The original high-resolution urban area photography distributed by the USGS came with metadata that incorrectly reported it as being 0.3098 meters per pixel (rather than 0.3048) - a typo, probably - and we did the math with the wrong number and never got around to changing it. The short answer is better - the label "1 ft/pixel" next to that scale is correct on any display or printer, and is a much better way of describing the resolution of the image. Quote Link to comment
+PFF Posted July 19, 2007 Share Posted July 19, 2007 (edited) Wow! Interesting....and the first explanation I've heard which actually makes sense. Thanks! Folks sometimes ask me why I pay $50/year for photos which are available for free elsewhere on the Internet. The great thing about TopoZone is the ability to mark a spot and then page between the Topo map, a 1993 black&white photo, a 1998 infrared photo, and (when available) a "urban high-resolution" photo. All the while, a red "index dot" remains fixed at the coordinates. The registration between the map/photos is not perfect, but it is close enough for benchmark hunting. You can tell in advance that a disk with adjusted coordinates is in the woods, or in the center of a plowed field, or under a ribbon of pavement. I use the TopoZone service quite a bit in my real estate practice. Hence, the $50/year is tax-deductible. The same would be true for a few other professions, as well. Being a serious benchmark hunter, I'd subscribe, even without the tax benefit. It is a valuable tool. While benchmarking, it's also a great public relations move to give the land owner an aerial photo of his/her property. It really "greases the skids" for getting access to marks on private property! -Paul- Edited July 19, 2007 by PFF Quote Link to comment
edmcnierney Posted July 19, 2007 Share Posted July 19, 2007 Folks sometimes ask me why I pay $50/year for photos which are available for free elsewhere on the Internet. Paul, you can also point out that while some of these photos are indeed free in some locations (if you can find them), some of the popular sites (e.g. Google) have MUCH poorer-quality photos outside of urban areas. And you get all the other goodies, including the fine, personalized technical support from a couple of map nerds - try getting THAT from MapQuest! Quote Link to comment
+PFF Posted July 20, 2007 Share Posted July 20, 2007 TopoZone Ed wrote: And you get all the other goodies, including the fine, personalized technical support from a couple of map nerds - try getting THAT from MapQuest! I agree. You and the gang are great, and you consistently respond very quickly. New topic: When are the "map nerds" going to mount a company expedition to log some benchmarks? Let's get the TZ guys and gals out of their cubicles, and away from the computer screens, and into somebody's yard! -Paul- Quote Link to comment
+GEO*Trailblazer 1 Posted July 21, 2007 Share Posted July 21, 2007 Interesting. The kind of data us Calibrater's love to play with. I have some things I am playing with and now I see the why. I also love OLD Maps from the USGS. Hard to find but well worth the efforts. I happen to know a guy who's Dad was a Surveyor and sold Topographic Maps. He said to come by which I did and he gave me a whole bunch of Old Topo's. I still have great fun with them. Quote Link to comment
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