James,

   Mine does't. I don't know if it is just my particular instrument.

Bob


Sent from my iPhone

On Jan 3, 2010, at 11:43 PM, James Parton <[email protected]>  
wrote:

> Bob,
>
> The Nikon Forestry 550 sounds cool. Does it penetrate through
> foreground clutter anywhere near as good as the Nikon 440 does?
>
> JP
>
> 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 = 38 
>>> ², 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 differ 
>>> ence
>>> 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. Obvi 
>>> ously
>>> this can not be same one that is used in the Suunto¹s, looking t 
>>> hrough
>>> it with an optical illusion. Maybe a tiny gun sighting built into  
>>> the
>>> volume and/or ringer buttons on the left side. I think someone
>>> thought of this earlier. With the sight and practice I believe one
>>> could the angle down to the nearest tenth of a degree. With the
>>> Suunto one can only really estimate anything less than 1 degree.
>>> Beth
>>
>>> --
>>> Eastern Native Tree Societyhttp://www.nativetreesociety.org
>>> Send email to [email protected]
>>> Visit this group athttp://groups.google.com/group/entstrees?hl=en
>>> To unsubscribe send email to [email protected]
>>
>> --
>> Eastern Native Tree Societyhttp://www.nativetreesociety.org
>> Send email to [email protected]
>> Visit this group athttp://groups.google.com/group/entstrees?hl=en
>> To unsubscribe send email to entstrees 
>> [email protected] Hide quoted text -
>>
>> - Show quoted text -
>
> -- 
> Eastern Native Tree Society http://www.nativetreesociety.org
> Send email to [email protected]
> Visit this group at http://groups.google.com/group/entstrees?hl=en
> To unsubscribe send email to [email protected]

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