Hi all - I've got a corporate shoot coming up in 10 days for which they want me to shoot 30 or so 'sites' over three days, with each site becoming a photosynth. I haven't done a synth before, so I was wondering if someone might give me some good advice on shot selection/camera position/what works and what doesn't. Also, can you upload files of different resolution for the same synth (ie. use lo-res shots of areas that have no interest)? People and movement? Small scenes? I know nothing.
Any and all help/advice/gentle words of nurture would be greatly appreciated. Thanks.
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EMPLOYEE1Richard -- my advice is start small (20-50 photos), and start practicing NOW. You should of course read our guide to photographers.
Resolution doesn't matter (the more the better), but exactly how you cover the area with photos does. Read the doc, practice, and ask questions about your results on our forums on the Photosynth site.
Richard, in addition to the Photosynth Photography Guide, here's the tutorial video.
How to Synth with Laura Foy
To get you jump started into synthing theory, I'm going to link you to some conversations where people are reporting how things have gone wrong for them and where myself or others have tried to explain what to do differently. As you suggest, sometimes knowing what not to do is as helpful as knowing the right thing to do and the best teacher is experience, so take as much as you can from our experiences. Don't be put off by people's failures. Everyone is somewhere on the learning curve and no one has mastered everything, but it's more than possible to get satisfying results.
A few quick pointers before you hit the reading assignments:
1: I'll tell you right away that my personally biased favourite technique from the guide and the video tutorial (for purposes of 3D modeling) is orbits - that is to say circling an object. In the following links this will become increasingly clear. There's nothing in Photosynth that necessarily requests circular camera motions, but rather it is trying to identify the same points in multiple images and it only does this well if the photos are taken with a difference of less than 25 degrees moving around a subject. You make the matching that much simpler if you maintain a particular distance and when you are maintaining a particular distance and varying your perspective on a subject, you end up with an orbit or a series of orbits. Taken to the extreme, this would result in full spherical coverage of an object which would be amazing, but is not necessary.
Examples: If you want to see see a tree's trunk in the 3D point cloud, then circle the trunk with photos. If you want to see the fire hydrant in the point cloud, then circle it with photos. If you want to see the vintage door handle in the point cloud, then circle it with photos. If you want to see the inscription carved below a sculpture, don't be afraid to circle the letters with photos. You get my point. ツ It's possible to overdo this, but almost all people new to Photosynth err in the opposite direction of just glancing at things as they shoot a series of panoramas. (I personally made this mistake when I first began, so I'm not criticizing anyone too unfairly.)
2: Try to take no fewer than 24 photos when circling something.
3: Stop thinking of things as whole objects and think more about individual surfaces. i.e. "Have I captured the wall or door or welcome mat of this house from a reasonable number of angles?", rather than thinking of the entire house as one object.
4: If you want more points, zoom in or get closer (just as when you want more pixels of a subject, you zoom in or get closer).
5: As the above points probably make clear, shooting photosynths is extremely different than shooting panoramas. Although Photosynth now hosts panoramas stitched by Microsoft ICE, the techniques used to shoot a clean panorama (no parallax) and the techniques to shoot a synth for purposes of 3D reconstruction (maximize parallax) are inverse to each other.
6: Scale matters. If you have an extremely wide shot and a close up, you'll need to have some intermediate shots walking between those vantage points. A little secret about Photosynth is that, although it uploads the full resolution photos, it only scans for image features to then match at 1.5 to 2 megapixels, so as to be able to put more photos together. Think of the wide angle shot of that object in the distance. It doesn't matter if you're shooting at 24 megapixels; in terms of whether Photosynth is going to match it to the close up, you've got to think of the number of pixels that little subject is going to be represented by when Photosynth looks at a 1.5 megapixel version of the whole frame. The difference between that and when that object fills up the frame (even only a 1.5 megapixel frame) is substantial. The good news is simply that if you don't let the percentage of the frame that something occupies more than double between the two closest shots of it, the matching should do just fine.
The discussions I alluded to above.
Synth not 360 (not including all photos)?
How to select where photos overlap?
Linking issues on a massive Synth
Biggest Synth Possible
This is MADDENING
Why the photo resolution doesn't matter:
Best size for each image?
A couple of other videos to help you get a sense of what's going on:
Photosynth on GeekBrief with Cali Lewis and David Gedye
ShutterSpeed Episode 04 - The Photosynth Team with Nic Fillingham, Blaise Agüera y Arcas, Drew Steedly, and Scott Fynn
My street cred to help you decide whether you want to listen to me or not.
(Use the [ P ] key to toggle from Photos Only to Photos + Points to Points Only...)
Orbital Propulsion: Gravity Assist
by Nathanael containing 731 Photos which were 100% Synthy
The Beaver Grove Sign
by Nathanael containing 717 Photos which were 100% Synthy
Oregon Veterans Medal of Honor Memorial
by Nathanael containing 760 Photos which were 100% Synthy
Charles and Waltraut's Hospitality
by Nathanael containing 284 Photos which were 100% Synthy
Memorials at Oregon's Capitol
by natelawrence containing 1376 Photos which were 100% Synthy
Deep Wood House: South Lawn (Last 1200)
by Nathanael.Lawrence containing 1200 Photos which were 100% Synthy
Deep Wood House: Greenhouse
by Nathanael containing 1692 Photos which were 93% Synthy
Salem Capitol Lobby (Very Rough Draft)
by Nathanael containing 1751 Photos which were 89% Synthy
Pro tips for analysing synths:
1: Use the full stop [ . ] and comma [ , ] keys to travel through the photos in a synth in the order of their filenames, rather than the default Photosynth spatial order. This allows you to follow the steps of the photographer (provided that the synth is not a mix of multiple different shoots with duplicated filenames between the sets). (This is most effective in synths with high synthy percentages because you won't be teleported between different groups of photos because there will only be one group of photos.) A full listing of the keyboard commands can be found at the end of the Photography Guide.
2: If you own an iPod Touch or iPhone, quickly download the free iSynth app. It includes an invaluable feature which no other Photosynth viewer currently offers which is to be able to see all of the camera positions in the context of the point cloud. Load up the most interesting synths in the app and you can plainly see what camera movement the best photosynth authors have used to achieve their results.
3: Use 2D View to understand which photos are matching together and how many clusters of photos are in a synth. You can use the icon in the Photosynth viewer or just press the [ ~ ] key to toggle between 2D and 3D.
4: If you're running Windows and have the Photosynth app installed, scroll to the bottom of any synth's viewing page and look on the lower left for a link to the older Direct3D Photosynth viewer, as it's faster and smoother and better for viewing point clouds..
I am very point cloud centric, but an excellent Photosynth doesn't have to be:
Campanario de Dumaguete
by almostchristian containing 18 Photos which were 100% Synthy
Still Life with 40 Apples
by David containing 35 Photos which were 100% Synthy
Climbing Sentinel (with highlights)
by K containing 408 Photos which were 96% Synthy
Provided that you get enough overlap, shooting multiple panoramas can work.
Catalina Island California
by robert_sprout containing 349 Photos which were 100% Synthy
Further Recommended viewing:
Mika And Herself // 3D Magic Trick // Go Game
Hiroshima A-Bomb Dome! (guided tour, and scavenger hunt!)
Jennie // Professional Go Game
Huge House (with highlights)
Cenote Samula, Valladolid, Yucatán
Martello Tower: Inside & Out
Kiholo Bay Inlet - Kite Aerial (KAP)
What is in the old Coffee Mill ? / SYNTHOMAGIC
What is in the apple ? / SYNTHOMAGIC
Santa Barbara Courthouse // Inside and Out
Lily - Red Rum
Nine Dragon Screen Wall, Forbidden City, Beijing
Cologne Cathedral - Kölner Dom, Germany
Regis University Main Hall and Chapel Combined
Hang Gliding over Yosemite Valley
National Geographic - Sphinx
National Geographic: Stonehenge Revealed
National Geographic: Hagia Sophia - Grand Hall
National Geographic - Roman Colosseum
Photosynth Pumpkin 2.2
Kew House Photosynth
Face Study #01 - Point Cloud Density
Nellie Inglerock - Masonic Cemetery
iNveridux - Intestinal Man's Petroglyphs
Medieval Castle, Guimarães, Portugal
Martin Luther King Jr. Memorial Park
US Constitution - National Archives
US National Archives - Constitution (With Highlights)
Gary Faigin Studio
Grassi Lakes by Pat Morrow
notre dame de paris
Boulder Dushanbe teahouse
Engaged at Pulhapanzak (with highlights)
Tom the Sleeping Kitten
Passage / Przejscie, Wroclaw, Poland
App Wall @ WWDC
1970 Volkswagon Beach Buggy
Trinity Rep Skylight
Torrey Pines State Reserve beach trail
Liana W Gray
Cathedral of the Most Holy Trinity (Bermuda)
My first photosynth
Christ the Redeemer
Sub Antarctic House
Another Tres Yonis Synth
Brayfield House, Cold Brayfield
Noah Snavely, Cornell University
Original Seadragon Office
How to Synth video: Interiors
How To Synth Video: Gasworks Park
GeekBrief synth with Cali Lewis
"Unfinished" Church St. George's Bermuda