Hi everybody, I agree that the classical rugged compass is the choice in 
remote areas and I would always bring one as a backup, but this summer, 
collecting hundreds of measurements every day on a very detailed 
transect across a fault zone, I started to see the advantages of a 
digital compass (that we didn't have), and particularly of automatic 
data logging. Now I have some issues on which I'd like to have more 
information, before going to the next shopping mall to buy a new phone...

Accuracy / precision: has someone tried to define this quantitatively 
for iPhone and/or Android phones? I'm more concerned with precision or 
reproducibility. Systematic errors, magnetic declination, etc. can be 
corrected easily...

Lineations: how do you measure them with phones? Precision?

Data logging: is there some data logging software with a customizable 
database structure, including the possibility to define different data 
classes for different projects?  Would it be possible to link a 
lineation measurement to a specific plane? This would be very useful in 
fault slip data measurements. Measurement station coding: sometimes the 
phone GPS is not working, or it is not enough in terms of accuracy. 
Would it be possible to record an ID for each data collecting station? 
Other data: sometimes you may need to record other data for each 
orientation measurement (e.g. thickness or  mineral filling of a vein, 
minerals marking a foliation, net slip along a fault, etc.). Can this be 
included in a customizable database?

Plotting: if it's possible to develop a more refined the database, 
plotting all these data in the field would be very useful...

BTW, is some other digital compass/clinometer/data logger available, not 
necessarily including a phone, but cheaper than GSI Geoclino?

Thanks very much!

Andrea



Andrea Bistacchi
Dipartimento di Scienze Geologiche e Geotecnologie
Universita' degli Studi di Milano Bicocca
Piazza della Scienza, 4
20126 Milano
[log in to unmask]

On 4/11/2011 2:20 PM, Jurgen Kraus wrote:
> I was wondering what the advantage of a cell phone compass is other than
> speed? It does not have the shape of a Klar compass and it relies on
> cell phone towers nearby, so not usable in areas such as the Canadian
> shield or the Gobi desert, not even in large parts of the Canadian
> Rockies. It appears to work with strike and dips (if I understand this
> correctly, which would be confusing for the 3-D worker) as opposed to
> dip direction. And if it is dropped, the stored data is gone.
> Considering how used my rugged Freiberger looks (with pencil notes on
> the lid), I wonder how long that plastic cell phone case will last in
> the field. Cell phones can also not be exposed to rain and to high heat
> (battery). And, it is difficult to attach it around one's neck, so the
> chance to leave it in the outcrop is rather big. Last but not least,
> when you camp out in the wilderness without electricity, it may be a
> challenge to charge the battery.
>
> In summary, I don't think the main concern is the software but the hardware.
>
>
> Jürgen Kraus
>
> Franconia Geoscience Ltd.
> http://franconia-geo.com/
> 2011 - 20th Ave SW
> Calgary, AB
> CANADA T2T 0M1
> [log in to unmask] <mailto:[log in to unmask]>
> +1 (403) 245-2206
>
>
>
> <http://franconia-geo.com/>
> <http://franconia-geo.com/>
>
> On 2011-11-04, at 7:00 AM, Pavlis, Terry L wrote:
>
>> thanks--I was interested in the accuracy question! And I've been using
>> your program and like it a lot--so this was a question in general on
>> this issue.
>> Terry
>> *From:*Tectonics & structural geology discussion list
>> [mailto:[log in to unmask]]*On Behalf Of*Marco Foi
>> *Sent:*Friday, November 04, 2011 3:24 AM
>> *To:*[log in to unmask] <mailto:[log in to unmask]>
>> *Subject:*Re: geoclino software
>> Il 03/11/2011 22:02, Pavlis, Terry L ha scritto:
>> Has anyone tried the new software from GSI in Japan?
>> http://www.gsinet.co.jp/english/software/android.html
>> If this works, it is a lot cheaper than buying their expensive digital
>> compass; aka the Geoclino.
>> Terry Pavlis
>> Univ. Texas at El Paso
>> Hi Terry.
>> Please let me begin with stating that what I am writing is a
>> non-neutral opinion.
>> This is so as in 2009 I devised and created eGEO Compass: the very
>> first geological compass for Android ever made.
>> (You can read about it, wiew some screenshots and download the 'app'
>> here:http://www.mcfoi.it/egeo_compass/)
>>
>> I cannot release some quantitative information on this ML but the key
>> point of your question is quality of data.
>> Since it can be assumed that all applications 'work' (otherwise they
>> would not be sold!), it is a matter of taste wether you prefer GSI one
>> or mine.
>> What I can say is that both are affected by the hardware they run on.
>> In the case of GSI Geoclino, the whole product (hardware and software)
>> was designed by GSI.
>> In the case of Android (or iPhone) apps the same software can behave
>> slightly different depending on the adopted phone, depending on the
>> quality of its sensors and its electronics design.
>>
>> As a general answer "yes: Android geological compasses DO WORK"...
>> ..and they do their work in a small fraction of the time. Two seconds
>> for capturing dip data with pitch against 3 minutes for the same
>> action using analogic compasses.
>>
>> You should consider them as a tradeoff between a slow-but-accurate
>> (500USD) analogic Geo Brunton and a fast-but-expensive (1400USD!!)
>> digital GSI Geoclino.
>>
>> Marco Foi
>>
>> --
>> Università degli Studi di Milano
>> c/o Dipartimento di Scienze della Terra
>> Via Mangiagalli 34
>> 20133 MILANO
>> ITALY
>> tel. 39-0250315503
>> fax    39-0250315494
>> E-mail:[log in to unmask]  <mailto:[log in to unmask]>
>