Bob, Also have you tried out one of those electronic clinometers like Haglof makes? Come to think of it, I think Larry Tucei has one of those. I just wonder how they compare with the Suunto.
JP On Jan 5, 11:38 am, James Parton <[email protected]> wrote: > Bob, > > Thanks for the explanation. One thing is for sure, I enjoy measuring > trees by this method when I am out. I think I have it pretty much down > but still I need more practice at being proficient at it. I was going > over what I learned at Congaree last year, doing tree spread. They are > a couple of ways. Take two measurements, four spokes and average them. > Say 15y by 20y. You would add them together and divide them by two to > get the average. right? And then take the answer and times that by > three to get it in feet. 15+20=35 divided by 2=17.5 x3 = 52.5 That is > 52.5 ft average spread. I also seen in Congaree where multiple > measurements are made by circling the tree making multiple > measurements for improved accuracy. I looked up and read on how to > measure max and average spread on the website but wanted to know > whether I had the averaging number formula right. I never was a math > wiz. ~laughing~! > > I find it awesome that ENTS and a few independents have influenced > tree measuring so much that Nikon and others now produce rangefinders > to cater to that need. As you stated, before us rangefinders were made > primarily for sporting activities. Hunters still use them a lot, for > example. > > I have to thank all ENTS but especially You, Larry Tucei, Will Blozan > and Ed Frank for helping me learn this amazing method. I would > encourage all non measuring ents to learn it. It really is fun! > > James Parton > > On Jan 5, 9:39 am, [email protected] wrote: > > > > > James, > > > BVP was independently using the sine top sine bottom method first. There > > may have been others as well, but I'm unaware of who they would have been. > > Will Blozan and I developed sine top and sine bottom for ENTS. We later > > discovered that BVP and been using it for a long time. Colby Rucker later > > joined Will and me and became known for his use of long poles to get a > > better fix on the lower measurement. Colby was just great. I miss him a > > lot. We all do. > > > BVP was the one who introduced Will and me to the Litespeed 400, a Bushnell > > laser. I got one and so did Will. Everything was uphill thereafter. The > > rest is history. > > > In terms of the tree math, my strong suit has always been mathematics. I > > developed mathematical models in my work while in the Pentagon and have > > taught math and statistics at the college level. So, tackling the problem > > in a mathematical way conforms to my nature. I say this because it has > > always come as a surprise to people outside the world of forestry that such > > basic calculations as we use haven't been in practice for decades. I always > > explain that those calculations were not possible prior to the introduction > > of the laser rangefinder. As to the expertise of mensurationists, they know > > the math. It's elementary, but they don't spend the time decoding hard to > > measure trees in forest situations. It's rather like knowing some > > principles of animal tracking versus being out there doing it. It took me > > three separate trips to tie down that tuliptree in Montpelier. I'm within > > +/- 0.5 feet of the twig I was measuring, but the effort required speaks to > > the difference of pointing, shooting, and writing down some numbers versus > > getting it right. ENTS knows better how to do that than any other group in > > the East. Of that, I have no doubt. > > > The Forestry 550 does measure tree height by our sine top, sine bottom > > method. The TruPulse does it also, but not by the built in height routine. > > It requires mores steps. BVP's Impulse Laser also does it right, but not by > > the built in routine. He also must use more steps. The OPTILOGIC appears to > > do it by the old tangent method. Pity. > > > Before ENTS people were using laser rangefinders in sports and other > > endeavors, but judging by the feedback we have gotten, ENTS has been really > > the only show in town in terms of employing laser rangefinders in tree > > height measuring. There's no way of knowing who might have been out there > > in tree-land doing it on their own. They didn't come forward. > > > The tangent-clinometer method was used before ENTS. It has been in use for > > decades. I suspect that early measurements of standing trees employed this > > method with some instrument being used to measure the vertical angle. The > > method of similar triangles would also have been used. Descriptions of > > equipment used and measuring methodology have been lost, if they were ever > > known. Thus, we get reports of astounding tree heights, but no way of > > verifying them. We'll never know what grew in centuries past. > > > A laser by its self can be used as you describe. However, looking upward > > and trying to shoot exactly straight up (90 degrees) is harder than one > > might imagine. When you think you are looking straight up, it is often at > > an angle of 70 to 75 degrees. A short make shift plumb bob can be used to > > create a true vertical line. > > > I think this covers everything. > > > Bob > > > ----- Original Message ----- > > From: "James Parton" <[email protected]> > > To: "ENTSTrees" <[email protected]> > > Sent: Monday, January 4, 2010 10:47:21 PM GMT -05:00 US/Canada Eastern > > Subject: [ENTS] Re: Suunto vs. iPhone > > > Bob, > > > ENTS came up with the Sine-Top Sine-Bottom method of measuring, right? > > I also know that some others have used lasers to measure trees more > > recently? Has ENTS inspired the use of laser rangefinders as tree > > measuring tools so much to grab Nikon's attention to build a laser > > specifically for measuring trees? And then there is those Tru-Pulse > > lasers and the one that BVP uses. Was lasers being used of any > > frequency before ENTS? I have always thought the tangent clinometer- > > only method was in use before You and Will developed our highly > > accurate method. I also know that a laser can be used by itself from > > under the tree if the top can be found as in a decideous tree in > > winter without the need of the clinometer. > > > Fill me in on laser usage history. > > > James Parton > > > On Jan 3, 3:19 pm, [email protected] wrote: > > > Carolyn, > > > > The Nikon Forestry 550 does it all. It is also fairly pricey. You select > > > the height mode, shoot the crown, shoot the base, and read the calculated > > > height from the LED. No math. No fuss. No bother. > > > > Bob > > > > ----- Original Message ----- > > > From: "Carolyn Summers" <[email protected]> > > > To: [email protected] > > > Sent: Sunday, January 3, 2010 2:35:23 PM GMT -05:00 US/Canada Eastern > > > Subject: Re: [ENTS] Suunto vs. iPhone > > > > Are there any tree-height measuring devices that do the math for you? I > > > never took trig. > > > -- > > > Carolyn Summers > > > 63 Ferndale Drive > > > Hastings-on-Hudson, NY 10706 > > > 914-478-5712 > > > > > From: Beth <[email protected]> > > > > Reply-To: <[email protected]> > > > > Date: Tue, 22 Dec 2009 15:57:09 -0800 (PST) > > > > To: ENTSTrees <[email protected]> > > > > Subject: [ENTS] Suunto vs. iPhone > > > > > A Small Comparison between Suunto and iPhone Clinometers > > > > > Since some of us now have iPhones and have downloaded the > > > > Clinometer application I thought that someone needs to compare the > > > > iPhone to the Suunto clinometer. Today I took 14 measurements each > > > > while sitting on my couch to a ceiling heating/AC vent. I then > > > > measured my eye height, the ceiling height, and the distance from my > > > > eyes to the tape measure hanging from the vent as a plumb bob. These > > > > measurements were: ceiling height = 96², height of the eyes = 38², and > > > > distance to the vent plum bob = 219². I used the measurements to > > > > calculate the angle I was trying to measure with the Suunto and > > > > iPhone. Before taking my measurements I calibrated my iPhone > > > > clinometer according to the instructions. I also had the following > > > > settings: Fast approximation-on, Beep on lock-on, wait for lock > > > > accuracy of + 0.1o- all the way to the left (+ 0.1o), disable auto- > > > > lock-off, and 3D glass effect-on. > > > > > The first thing that I do in order to calculate the angle A was to > > > > calculate the distance from my eye to the ceiling; 96²-38²= 58². > > > > > Since Tan A = a/b, we can rearrange the equation to find A by dividing > > > > both sides by Tan. Since 1/Tan =Arc Tan the equation is A = (a/b) Arc > > > > Tan. Filling in this equation with the data we get A = (58/219) Arc > > > > Tan or A = 14.8336707057. Taking signifiginte numbers in mind I am > > > > going to say the angle is 14.8o. (Note: I calculated this after > > > > gathering the data as not to influence the clinometer data) > > > > > Now for the clinometer data: > > > > Suunto iPhone Suunto iPhone > > > > 15.5 15.2 14.5 15.4 > > > > 15.0 14.9 15.0 15.2 > > > > 15.0 15.1 14.5 15.2 > > > > 15.0 14.1 14.5 15.1 > > > > 15.0 15.0 14.5 15.7 > > > > 15.0 15.2 15.0 15.5 > > > > 14.5 15.1 14.5 15.2 > > > > The means were 14.8 and 15.1 for the Suunto and iPhone respectively > > > > with standard deviation of 0.31 and 0.35. > > > > > The one thing I noticed in my raw data is with the Suunto my highest > > > > and lowest angles were 15.5 and 14.5 whereas with the iPhone they were > > > > 15.7 and 14.1. I can think of at least two reasons why. 1) I have > > > > more experience with the Suunto than I have with the iPhone and 2) the > > > > Suunto has a line to help repeatly ³hit² the same spot whereas the > > > > iPhone you are just looking down one side of the phone. > > > > > I also noticed after calculating the angle (14.8) the Suunto average > > > > was closer than the iPhone¹s (14.8 vs. 15.1). Now is 0.3o difference > > > > significant? Bob has more experience with the Suunto than I do and he > > > > has stated in the past that can read it to the nearest 1Ž4 o. I myself > > > > can only read it to the nearest 1Ž2o. Given this I believe that a > > > > difference of 0.3o is. > > > > > How can the iPhone be improved? If one would add a sighting device on > > > > to the iPhone this could help ³hit² the same spot repeatly. Obviously > > > > this can not be same one that is used in the Suunto¹s, looking through > > > > it with an optical illusion. Maybe a tiny gun sighting built into the > > > > volume and/or ringer buttons on > > ... > > read more »- Hide quoted text - > > - Show quoted text -
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