Attitude in EXIF?
Oskar Sander
Most cameras have at least one tilt sensor (r), but it would be nice to have tilt around all axis and heading. This could be used as initial values for optimizations for hand held panoramas (mosaics in my case)
Cheers
/O
Karmadillo
binary output. This would not provide the information you want.
Karmadillo
about tilt angles in all dimensions.
If you could securely attach your iPhone to your camera or tripod
head, and then calibrate it, you would get the type of information you
seek.
However Clinometer doesn't output any data so you would need to
manually record it for each photo.
Oskar Sander
Does the EXIF standard permitt custom data fields (like in this case adding heading, rotation, pitch and yaw). In that case it would be possible to use this infor to generate starting ypr values in hugin.
I was thinking about getting one of these x-IMU that include logging to SD-card. However these have a lot of nice other functionalities so they are a bit of overkill (http://www.x-io.co.uk/node/9)
Cheers
/O
>There is an iPhone App "Clinometer" that provides very detailed data
>about tilt angles in all dimensions.
>If you could securely attach your iPhone to your camera or tripod
>head, and then calibrate it, you would get the type of information you
>seek.
>However Clinometer doesn't output any data so you would need to
>manually record it for each photo.
Well, there is a sample/demo application (APIdemo?) in the Android SDK,
which displays three animated line graphs, one for each axis resp.
acceleration sensor, same for compass. The SDK is free, so it's just a
matter of adding a few lines to that sample, in order to automatically
record the datat locally or to send it via net internet to some
listening service. If storing the data locally is sufficient, using an
old, abandoned phone for that purpose might come to mind.
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Jeffrey Martin
that would be really really awesome :)
Jeffrey Martin
I think it might be.
anyway, people HAVE built a homebrew GPS device to connect to nikon SLR
http://grink.com/2010/12/05/nikon-d90-homemade-gps/
could the same be done with this position-ometer?
http://www.x-io.co.uk/node/9
it would be so cool!
Jeff
kfj
On 5 Dez., 17:17, Jeffrey Martin <360cit...@gmail.com> wrote:
> I like this idea so much, that I continued doing a bit of research on
> whether it's possible.
>
> I think it might be.
> could the same be done with this position-ometer?http://www.x-io.co.uk/node/9
> it would be so cool!
A few years ago we had phones. Now we have smartphones. Let's hope we
also get 'smartcameras'. When I look at the computing capacity of my
camera (as revealed by the quite sophisticated image processing) and
contrast that to the meagre essentials my firmware allows me to
manipulate, I feel cheated somehow... I hope open firmware takes off.
GPS has already made it's way into compact cameras, quite probably
because geotagging can instantly be recognized by a significant part
of the general public as a useful feature. Inclinometer data might be
sold to the public as an aid to automatically level the horizon, and
since that is one of the commonest photographic mistakes it might be
the route for these devices into cameras.
Mind you, probably into compact cameras - and if you have a DSLR
you'll be asked to fork out 500$ for some bulky stick-on device which
only works with the top of the range and drains your battery in no
time. The device you dream of sticking to your camera seems like
overkill to me. Nice-to-have, but really one of the small sensors like
those inside a smartphone would do the trick well enough - and they
are much cheaper, as well :)
Kay
Frederic Da Vitoria
>
>
> On 5 Dez., 17:17, Jeffrey Martin <360cit...@gmail.com> wrote:
>
>> I like this idea so much, that I continued doing a bit of research on
>> whether it's possible.
>>
>> I think it might be.
>
>> could the same be done with this
>> position-ometer?http://www.x-io.co.uk/node/9
>> it would be so cool!
>
> A few years ago we had phones. Now we have smartphones. Let's hope we
> also get 'smartcameras'. When I look at the computing capacity of my
> camera (as revealed by the quite sophisticated image processing) and
> contrast that to the meagre essentials my firmware allows me to
> manipulate, I feel cheated somehow... I hope open firmware takes off.
For those who have a Canon compact or bridge, this
http://chdk.wikia.com/wiki/CHDK is a proof that the hardware is able
to do much more than we usually think. I use it in my S5 and it works.
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Jeffrey Martin
On Tuesday, December 6, 2011 8:52:59 AM UTC+1, kfj wrote:
A few years ago we had phones. Now we have smartphones. Let's hope we
also get 'smartcameras'.
I have very little hope at this point. Or, you could consider that "they" (canon, nikon, etc.) might do it, 5 or 10 years after you think they should ;)
When I look at the computing capacity of my
camera (as revealed by the quite sophisticated image processing) and
contrast that to the meagre essentials my firmware allows me to
manipulate, I feel cheated somehow...
Totally. It is outrageous in fact. There is so much possible, and so little being done, in the cameras. It is a shame. And they can't even open up the camera to allow user scripting. WTF? :(
I hope open firmware takes off.
GPS has already made it's way into compact cameras, quite probably
because geotagging can instantly be recognized by a significant part
of the general public as a useful feature.
Well, there is still the problem of battery life. I think this is one of the biggest factors about why there isn't GPS in more cameras. But still that's a pretty lame excuse.
Inclinometer data might be
sold to the public as an aid to automatically level the horizon, and
since that is one of the commonest photographic mistakes it might be
the route for these devices into cameras.Mind you, probably into compact cameras - and if you have a DSLR
you'll be asked to fork out 500$ for some bulky stick-on device which
only works with the top of the range and drains your battery in no
time. The device you dream of sticking to your camera seems like
overkill to me. Nice-to-have, but really one of the small sensors like
those inside a smartphone would do the trick well enough - and they
are much cheaper, as well :)
That's a good point. It's true that the phones have the same sensors (magnetometer, accelerometer, gyroscope). You could make an iphone/android app to do the same thing.Trouble is of course, how to stick the phone on your camera's flash hot-shoe? :-)))
Oskar Sander
With GPS there are add ons to e.g. Lightroom that correlates at GPS track with photo timestamp and add position in metadata. This electronic tripod/attitude could work the same.
Cheers
/O
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Geoff G8DHE
Jeffrey Martin
and the answer is definitely NO - GPS is very course, and in practical purposes, you can have the sync off by a few seconds and the photos will still have correct location data. not the case with the position of the camera in space. and there is no way you can synchronize a non-tethered device within 1/100 of a second or whatever it takes to correctly synchronize such data.
so a device like this will have to be tethered.
in terms of the compass.... i've noticed using my analog compass that i can't hold it too close to my camera or it is wrong. so i wonder how an electronic compass will be able to deal with that.
finally, in terms of custom exif data.... if we are to build this for nikon, we'll need to hack the position data inside the exif data. i don't think there will be any other way. we'll see ;)
now, what nikon slr should i buy? i've been a canon guy up till now :(
Frederic Da Vitoria
user-defined data.
2011/12/6, Jeffrey Martin <360c...@gmail.com>:
--
Carl von Einem
> I was thinking more about this, and whether an external logger with sync
> (like you do with gps) would be possible
One other option that doesn't directly write data in the images EXIF
metadata would be a timestamp for the external logger via the camera's
flash sync contact. A rough time synchronisation of the externally
logged data with the camera could be done with a simple display on your
device showing the current 'hhmmss' value that just needs be
photographed once in a while. Correct the EXIF timestamp with a simple
exiftool argument later.
> and the answer is definitely NO - GPS is very course, and in practical
> purposes, you can have the sync off by a few seconds and the photos will
> still have correct location data. not the case with the position of the
> camera in space. and there is no way you can synchronize a non-tethered
> device within 1/100 of a second or whatever it takes to correctly
> synchronize such data.
>
> so a device like this will have to be tethered.
>
> in terms of the compass.... i've noticed using my analog compass that i
> can't hold it too close to my camera or it is wrong. so i wonder how an
> electronic compass will be able to deal with that.
I think I sometimes see compass errors when I get too close to the
camera / pano head with my Garmin Oregon. But with a sensor you could
use some kind of "antenna" that provides the necessary distance.
> finally, in terms of custom exif data.... if we are to build this for
> nikon, we'll need to hack the position data inside the exif data. i
> don't think there will be any other way. we'll see ;)
The exiftool website has some more information, e.g. here
<http://owl.phy.queensu.ca/~phil/exiftool/TagNames/GPS.html>
> now, what nikon slr should i buy? i've been a canon guy up till now :(
I think a lot of people are waiting for the D-700 successor, usually
referred to as D-800. Still the D-700 seems to be a trustworthy full
frame dslr while the D-300s is the current DX (= 1.5 crop factor)
equivalent. I use a D-300.
You'll love the bracketing feature :-)
Cheers,
Carl
Jeffrey Martin
Jeffrey Martin
Ok, so it looks like the heading can be written into the GPS exif data without any hack?
That leaves only the pitch/roll data - We could probably stick this in the "altitude" field, since the altitude data is always totally wrong and useless anyway :)
Carl von Einem
>
> That leaves only the pitch/roll data - We could probably stick this in
> the "altitude" field, since the altitude data is always totally wrong
> and useless anyway :)
There is usually a huge difference between the height values coming from
the GPS data and the barometric output (my Garmin has both). So maybe a
barometric sensor is also available...
Carl
Geoff G8DHE
in terms of the compass.... i've noticed using my analog compass that i can't hold it too close to my camera or it is wrong. so i wonder how an electronic compass will be able to deal with that.
You need to calibrate any form of compass ! The Solmeta device requires that you put it in calibrate mode, and then twist the unit along all 3-axis twice so that it can record the maximum external field strengths, by recording the changes rather than measuring the static fields created by the camera/head/device. The accuracy and precision even after calibration is not that high 5° is good. Unless you go for some very expensive sensors.
Geoff G8DHE
Joost is also building in the ability to use the GPSImageDirection field into PTGui and I have suggested that he allow for Tilt and Roll as well, likewise Thomas is building in support for use within Pano2vr.
Frederic Da Vitoria
> We could also use EXIF Tools facility to define and code our own Custom
> fields ? See http://www.sno.phy.queensu.ca/~phil/exiftool/config.html
I always thought that Exif tags/fields started with pre-defined
identifiers. You could use one of the unused values, but you'd risk
that other applications do the same. Or am I missing something?
Geoff G8DHE
Reusing other Tags such as Altitude will mean that the data will be overwritten if you use other geotagging programs that use the field, say you used Geosetter to locate the image it would overwrite the Altitude info. and you would loose that data you carefully pushed into it!
Much better to define a new field, for the info now, then as and when a new Exif spec appears with what we want in it we can use ExifTool to move the data from our own defined field to the "real" one.
The major problem will be getting cameras to write non-standard info that there not expecting :-( Much better to go via the Logging route and then attach the new data into our custom field offline where it won't be over written.
JohnPW
Calibration makes up for any *stationary* interfering objects which is
why you can have a very accurate fixed compass on a ship or vehicle.
So the limitation Geoff points out is mostly a result of the sensor.
However, all the tripod and parts of the head are not "stationary"
relative to the panning camera. These parts also tend not to be
symmetrical and the actual sensor is unlikely to be at the npp (which
would be the center of symmetry.) Perhaps the effect is minimal
(depending on the rig?) or it could be that 5º is about as good as it
might get, without special attention to the design of the whole rig,
whatever the quality of the sensors.
Jeffrey Martin
that's why i suggested an ugly hack, writing the position info into the gps / altitude fields.
does anyone know if a better solution - writing into some other exif field - will be possible in nikon cameras?
as for using some other camera - i don't think it's possible. AFAIK only nikon allows tethered GPS loggers to write to the memory card while shooting. canon doesn't allow it....
kfj
On 6 Dez., 16:37, Geoff G8DHE <geoff.mat...@gmail.com> wrote:
> You need to calibrate any form of compass ! The Solmeta device requires
> that you put it in calibrate mode, and then twist the unit along all 3-axis
> twice so that it can record the maximum external field strengths, by
> recording the changes rather than measuring the static fields created by
> the camera/head/device. The accuracy and precision even after calibration
> is not that high 5° is good. Unless you go for some very expensive sensors.
My (Garmin etrex hcx) GPS has a compass, but it's not too precise,
needs calibration, and only produces correct data if the device is
held level (!) and there are no magnetic fields around. One would wish
for something better, but I'm not sure they exist. On the other hand,
the compass is the thing needed least for a panorama - the
inclinometer would be much more useful and it should work no matter
what.
Kay
kfj
On 6 Dez., 10:38, Jeffrey Martin <360cit...@gmail.com> wrote:
> On Tuesday, December 6, 2011 8:52:59 AM UTC+1, kfj wrote:
> > GPS has already made it's way into compact cameras, quite probably
> > because geotagging can instantly be recognized by a significant part
> > of the general public as a useful feature.
>
> Well, there is still the problem of battery life. I think this is one of
> the biggest factors about why there isn't GPS in more cameras. But still
> that's a pretty lame excuse.
Handheld GPS devices show that receiving GPS data doesn't need to
consume much power. My garmin can operate 20 hours on two AA NiMH
cells, and that's with it recording my track and displaying
everything.
BTW - GPS comes with extremely precise knowledge of the time - after
all the GPS satellites carry atomic clocks and the GPS devices sync
with them - time is at the basis of finding your position with a GPS.
If the GPS is inside the camera (and the camera uses the GPS's time -
I wouldn't put it beyond the camera makers to fail to do so) all
imprecise timing is a thing of the past. On top of that, radio time
signals are sent out to synchronize radio controlled watches, and
hardware to receive the signals is cheap. Yet again it's not that the
technology isn't there, it's just that it isn't used.
Kay
Geoff G8DHE
Specifys that the GPS Altitude record is a Rational number which is two 32bit unsigned integers (numerator & denominator).
However your going to need to strip those two values out of the Altitude field before any other program touches the data and overwrites the Altitude information.
I'm still inclined to go with using the Logger info from the Solmeta Pro where the $PTNTHPR sentences provide the heading, pitch, and roll information in one nice easy format!
$GPRMC,133656.000,A,5049.6748,N,00022.9357,W,1.73,145.09,030811,,,E*76
$PTNTHPR,218.9,N,-7.9,N,-3.2,N,A*19
$GPGGA,133700.000,5049.6744,N,00022.9365,W,1,03,10.6,24.9,M,47.1,M,,0000*41
$GPRMC,133659.000,A,5049.6734,N,00022.9377,W,1.77,198.54,030811,,,A*78
$PTNTHPR,246.4,N,-26.0,N,4.6,N,A*0B
$GPGGA,133747.109,5049.7042,N,00022.9503,W,1,03,10.0,30.4,M,47.1,M,,0000*42
Gnome Nomad
battery life: compact cams use a lot less juice. They're only moving a
tiny little lens around, powering a tiny little chip and not having to
flip a frame-sized mirror out of the way to take a picture.
So while a compact might have the battery life to support built-in GPS,
I'd really rather have my DSLR use its battery taking quality pictures.
Oskar Sander wrote:
> Right, I was going to say the same. Most iphone and andorid phone has
> this capability, soon every little gadget will too. The camera producers
> need to se the benefit though. Which I think instant panorama,
I've seen that on compact cameras, and iPhone. The pictures look great
on the little displays. They don't look very good at full size.
> 3D
> application etc would be.
>
> With GPS there are add ons to e.g. Lightroom that correlates at GPS
> track with photo timestamp and add position in metadata. This
> electronic tripod/attitude could work the same.
>
> Cheers
> /O
>
> 2011/12/6 Jeffrey Martin <360c...@gmail.com <mailto:360c...@gmail.com>>
--
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wandering the landscape of god
http://www.cafepress.com/otherend/
kfj
> One difference between compact P&S cams and DSLR when it comes to
> battery life: compact cams use a lot less juice. They're only moving a
> tiny little lens around, powering a tiny little chip and not having to
> flip a frame-sized mirror out of the way to take a picture.
This isn't necessarily true:
- you can easily work a DSLR without the monitor on most of the time.
Try that with a P&S
- DSLRs do not have to focus via the main sensor, so they don't need
processing power for that (and more power for the 'pumping' until the
correct focus is found')
- you zoom DSLRs manually, while P&Ss use a motor for the purpose
- P&Ss usually keep the lens inside the body and have to move it out
and back in on every power on/off
I used a P&S and routinely took spare batteries because they ran out
quite quickly. When I got a DSLR, I bought some spare batteries right
away, just to find out that I seldom need them (admittedly they're a
bit fatter).
> So while a compact might have the battery life to support built-in GPS,
> I'd really rather have my DSLR use its battery taking quality pictures.
you make it sound as if just having a GPS unit uses power. The good
thing about GPS units in this respect is that you can actually turn
them off ;-)
Kay
David Haberthür
On 07.12.2011, at 08:04, Gnome Nomad wrote:
> One difference between compact P&S cams and DSLR when it comes to battery life: compact cams use a lot less juice. They're only moving a tiny little lens around, powering a tiny little chip and not having to flip a frame-sized mirror out of the way to take a picture.
I disagree greatly. I've used my DSLR (an old Nikon D80) for shooting a wedding of friends. I've managed to get 1700 (!) pictures in one day (yes, also a lot of panoramas) with still some juice left in my battery. I think I'd never ever manage to do this with my compact cam. It's probably because the battery of my DSLR has approximately four times the physical size of the compact cams battery, and more than double the mAh in it :)
Otherwise the discussion in this thread is really interesting. I've been geotagging my photos since years, be it with a GPS logger or after importing them to my photo library with an external tool. It's not really the ultimate accuracy I want to achieve, it's more like 'where in the world have I been'.
Habi
Jeffrey Martin
Ok,
I think I'm going to go ahead and build this thing:
hotshoe-mounted attitude logger for Nikon SLR
using gyroscope, accelerometer, magnetometer, it will write the Heading, Pitch, and Roll of each photo into the exif data as the photo is shot.
Now, can anyone recommend which sensor device should be used?
This one seems suitable: store.ckdevices.com/products/Mongoose-9DoF-IMU-with-Barometric-Pressure-Sensor-.html
Any other suggestions?
Jeffrey
Oskar Sander
That board looks interesting.
Look at:
http://www.sparkfun.com/products/10736
http://www.x-io.co.uk/node/9 (which i considered as i want logging to memory card)
Cheers
O
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Geoff G8DHE
mgg
from the cell tower and uses that with GPS data. A camera would need
to work without it - though it isn't all that hard considering that
you can get tiny "puck" GPS to USB devices today. I expect it is more
about battery and keeping the cost down. I'd love to see bluetooth in
the cameras and a few APPs to go on smart phones. You could send GPS
to the camera or send EXIF data to the phone that you match up with
the phone's GPS data and any txt or audio notes you'd like to take.
Inclinometer data would be easy if phone is mounted to camera or near
camera. Compass data though would be highly suspect. Some ability
to send a thumbnail to the phone would be nice as well both to match
up with the exif but could also then be sent via email or SMS.
Of course bluetooth takes power too - but if you only used it to send
data to the phone - it would be pretty silent most of the time.
me
Geoff G8DHE
I created GPSRoll and GPSTilt within the GPS section of Exif and given them TagID's high up in the range so that they unlikely to conflict with any other added fields in the future.
One thing that needs to be noted we need a "standard" for the way that the values are shown i.e. What is +ve value in terms of rotation so I've used the Aircraft notation for Roll and Pitch/Tilt see http://www.grc.nasa.gov/WWW/K-12/airplane/rotations.html
The camera lens pointing downwards would be -ve and pointing Upwards would be +ve, the Roll is +ve when looking from behind the camera and the camera is tilted in a Clockwise direction.
The necessary additions to any ".ExifTool_config" file are;
%Image::ExifTool::UserDefined = (See here for where to place the file http://www.sno.phy.queensu.ca/~phil/exiftool/config.html
'Image::ExifTool::GPS::Main' => {
0xd000 => {
Name => 'GPSTilt',
Writable => 'rational64s',
WriteGroup => 'GPS',
},
# add more user-defined EXIF tags here...
0xd001 => {
Name => 'GPSRoll',
Writable => 'rational64s',
WriteGroup => 'GPS',
},
},
);
1; # end
The results are like this;
GPS Version ID : 2.2.0.0
GPS Altitude Ref : Above Sea Level
GPS Time Stamp : 17:15:18
GPS Img Direction Ref : Magnetic North
GPS Img Direction : 265.23
GPS Map Datum : WGS-84
GPS Dest Latitude Ref : North
GPS Dest Latitude : 50 deg 49' 40.77"
GPS Dest Longitude Ref : West
GPS Dest Longitude : 0 deg 22' 58.37"
GPS Date Stamp : 2011:12:05
GPS Tilt : -45.3
GPS Roll : 3.23
To display the results you need to add the -u flag to ExifTools to display the unknown fields like "Exiftools -k -u -g dsc0029.jpg"
Example file used above is attached.
The ExifTool GUI program doesn't use the -u flag either when obtaining data from files, so I have asked in the ExifTools forum if that might be a possibility in the future.
No doubt that there might be need for changes so any thoughts let me know and we can see what might need changing ....
Geoff G8DHE
Just make sure that if you have Geosetter installed that you don't have two versions of ExifTools installed .... you might be using the wrong copy ... :-( Oops
Gnome Nomad
> Hey all
>
> On 07.12.2011, at 08:04, Gnome Nomad wrote:
>
>> One difference between compact P&S cams and DSLR when it comes to
>> battery life: compact cams use a lot less juice. They're only
>> moving a tiny little lens around, powering a tiny little chip and
>> not having to flip a frame-sized mirror out of the way to take a
>> picture.
>
> I disagree greatly. I've used my DSLR (an old Nikon D80) for shooting
> a wedding of friends. I've managed to get 1700 (!) pictures in one
> day (yes, also a lot of panoramas) with still some juice left in my
> battery. I think I'd never ever manage to do this with my compact
> cam. It's probably because the battery of my DSLR has approximately
> four times the physical size of the compact cams battery, and more
> than double the mAh in it :)
I get about 800 frames from a pair of batteries in my Maxxum 7D. They're
larger than many compact cams are now. With our old P&S shoot compact
camera, I've shot many more frames than that over the space of a week
before having to recharge batteries.
> Otherwise the discussion in this thread is really interesting. I've
> been geotagging my photos since years, be it with a GPS logger or
> after importing them to my photo library with an external tool. It's
> not really the ultimate accuracy I want to achieve, it's more like
> 'where in the world have I been'.
That's something that would make GPS useful: Where was this picture
taken? (Well, also, to answer the question - now how do I get back to
where I was before I wandered off shooting pictures.)
Frederic Da Vitoria
> David Haberthür wrote:
>> Hey all
>>
>> On 07.12.2011, at 08:04, Gnome Nomad wrote:
>>
>>> One difference between compact P&S cams and DSLR when it comes to
>>> battery life: compact cams use a lot less juice. They're only
>>> moving a tiny little lens around, powering a tiny little chip and
>>> not having to flip a frame-sized mirror out of the way to take a
>>> picture.
>>
>> I disagree greatly. I've used my DSLR (an old Nikon D80) for shooting
>> a wedding of friends. I've managed to get 1700 (!) pictures in one
>> day (yes, also a lot of panoramas) with still some juice left in my
>> battery. I think I'd never ever manage to do this with my compact
>> cam. It's probably because the battery of my DSLR has approximately
>> four times the physical size of the compact cams battery, and more
>> than double the mAh in it :)
>
> I get about 800 frames from a pair of batteries in my Maxxum 7D. They're
> larger than many compact cams are now. With our old P&S shoot compact
> camera, I've shot many more frames than that over the space of a week
> before having to recharge batteries.
I have 2 compacts and 1 bridge, none of which ever managed to give me
more than 750 pictures per charge (and I never use the flash, seldom
review my photos in the camera and always transfer my photos by
inserting my card in my PC). I guess the only conclusion is that there
is no way to know in advance the number of pictures per charge based
on the camera type. Which makes sense, photos per charge would depend
of course on battery capacity (BTW when you wrote "large", you meant
in size or in capacity?) but also on the intelligence of the engineers
in avoiding unnecessary power drain, and on the way you use your
camera (do you take a long time to frame your pictures, do you spend a
long time reviewing the pictures after, do you use the flash) which in
turn is influenced by the camera type. Add to this the fact that old
P&S had an optical viewer (which diminished power consumption) while
in almost all modern P&S you have no choice but to use the LCD.