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I used to use a Lumia 710 and I have a 920 now. I do not use them for Photosynths, but I do take pics with them. Occasionally back then with the 710 and frequent with the 920. The standard photo app of the 710 did not even record geo co-ordinates, the Nokia Camera in the 920 does, but it does not record direction, although the 920 has a gyroscope. So, ...
1. Please make sure that geo co-ordinates and direction are recorded properly.
2. As pics may be taken on the move, have it possible to refresh location lock by location sensors.
3. I feel it might be useful to have a preview for them too.
Note that digital compass and gyroscope are two different sensors (and although you didn't mention it accelerometer is yet a third sensor and different again).
Accelerometers measure the relative force and direction of movement, gyroscopes measure the rate of relative rotation, and digital compass measures the bearing of the phone in relation to magnetic north. GPS is separate from these others.
Don't get me wrong, I'm all for recording all of the real world bearing and rotation data as possible, but Photosynth does calculate the relative poses of the cameras to each other (fairly accurately for the most part) so even if you only had a reasonably accurate GPS coordinate for each photo, as long as Photosynth can solve how they fit each other, then Photosynth will easily solve for bearing (compass)and rotation (gyroscope) and by comparing timestamp and GPS coordinate can infer the speed at which the path was traveled.
Having a sensor that measured altitude would be something quite useful, although I'm not aware of a phone that has one built in.
I'm not sure what you mean by 'refresh location lock'.
Do you just mean that each individual photo ought to have its own accurate GPS coordinates? I was under the impression this is default behavior in any app (such as Camera or Maps) which uses Windows Phone's geolocation APIs.
The 720 certainly had a GPS sensor in it for use with Maps etc. so the stock Windows Phone Camera app should have been recording GPS coordinates for photos. If you ever use one again, there is a setting to toggle this which can be found by navigating to Settings > Applications > Pictures & Camera.
Regarding a preview of photos taken for a synth thus far on the upcoming photosynth capturing apps (compared to today's panorama capturing apps), check out the Photosynth team's reply here: http://bit.ly/psfps2iview
Manufacturers and their retailers are bad in correctly specifying such sensors in their specs. But, I would prefer Photosynth apps to capture all available sensor date. Not to forget gps date and time, which I just found out is not captured by the current app. I feel having correct gps for panos and spins is quite useful.
I do not think there is a new gps lock after each movement. Maybe the location service calculates new positions for a while using the other sensors, before it gets a new gps lock. At least I want to know if I have a good gps lock if I start with the first shot.
I am not truely knowledgeable about it, but what I have read about it, altitude is a tricky thing. It could be added by post processing if gps co-ordinates are correct.
My Lumia 710 had a gps sensor, but the camera app did not include it in the file.
Thanks for this great input. We do plan to capture GPS and orientation data with each frame. Both of these are pretty noisy and poor resolution, but it will give us at least a starting point for accurate geo-positioning and orienting the synth in the world. Most importantly, because the indoor resolution of GPS is very poor, we do not expect to be able to determine the scale of the synth from differences in the GPS location of the frames alone. Dead-reckoning based on the inertial sensors is pretty poor too, so we're imagining that people will need to adjust the scale (at least) in a manual step after the synth is created.
Will individual frames also be available to the user?
Like Joscelin, I would like to see the ability to export the images taken with the new mobile apps to OneDrive or my own PC or the phone or tablet's camera roll for use in other applications as well.
I have engaged in shooting some spherical panos at road intersections in a neighbourhood. First time more serious use of Ps1 app on WP8 Lumia 920. After having shot 5 panos, I feel the device is rather hot. Also, battery level decreases fast. So, this is not something for a day out shooting. Hence, I suggest all image matching to be done at server side. But, keeping current functionality too, I would like to have ICE functionality at server side being able to save the ICE pano file to OneDrive.
So, apps only need to assist in shooting in the best possible way for the chosen synth type. The app should save the photo set of an elementary synth shoot to an automatically created folder within the camera roll folder.