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andyc1202 (Over 1 year ago)
Hi, I have uploaded two sets of pics, both in excess of 50 pics for a spin synth.
Although everything in order, pics numbered, a complete circle , one synth only goes half way round, and funnily i started and ended at the front of the car so it is giving me the first pics and the last pics...

second one has gone awry completely despite all pics being in order, take a look

this also doesnt go all round....

have a look at original pic uploads to see what i mean, the whole set is there.

Some advice would be good, or if it is a bug please advise.

andyc1202 (Over 1 year ago)
when it gets stuck, it jumps back 19 pics then restarts. it has missed the whole end of one end of the table!!!!!!
andyc1202 (Over 1 year ago)
moved to bugs forum!!!!
NateLawrence (Over 1 year ago)
This Technical Preview forum is fair game for anything related to the preview, whether that's questions, suggestions, advice, critiques, bug reports, announcements from the Photosynth team, etc. so don't feel like you need to move topics relating specifically to the preview to the other forums.
andyc1202 (Over 1 year ago)
Thanks for the hint Nate.

As a suggestion yet, and it may have been asked elsewhere here's an idea for uploading pics

Any chance of being able to add direct from SkyDrive?

If there is a way I not got it working yet.

I have the skydrive software on my pc (win 7) but I cannot sign in, it just hangs, I suppose this, when works (if ever works) will allow me to add and upload direct from the skydrive folder. Am I right in that thinking??

I ask about if it can be done DIRECTLY from skydrive as all my mobile photos are synced there as I take them and I would like to be able to make a synth straight away.

On my windows phone I can make 260 panorama's but nothing else from the app.

Thanks all.

NateLawrence (Over 1 year ago)
So, I've taken a look at your synths now (I'm just your fellow user - not anyone from Photosynth).

Bear in mind that everyone except the Photosynth team and you will not see the number of photos uploaded when making the synth. 
Instead, we are displayed the number of photos which succeeded in matching into the largest group of photos. At least that has been the case in the preview so far.

In your first synth (the car spin), I'm guessing that what may have happened is that you aimed the camera a little low, leaving only the car in view, which may not have provided Photosynth enough features to track between shots. If you reshoot that subject in that location, you might try keeping enough of the background in your shots to keep the reconstruction going all the way around to close the loop.
NateLawrence (Over 1 year ago)
The second synth (in McDonalds) is interesting in that clicking the Info icon lists 64 photos, but I count only 38 camera positions in the overhead map or moving through photos with the cursor keys, so I'm not too sure where the others are hiding.

I think that the problem there may be the plain textureless walls and shiny glass wall of the store as well as the slightly overexposed photos. 
This all adds up to photos with not many things for Photosynth to latch onto.

Photosynth will always do better tracking things which have a higher frequency visual texture - things like rock, cement, tree bark, fabric with a visible pattern, rugs, etc. that have lots of speckles and spots work great.

If you open the debug panel by typing 42 into the viewer, then check the pointCloud option and refresh the viewer, then enter global view with the C key and look at the point cloud, you'll be seeing which parts of the scene Photosynth was able to track among the photos.
NateLawrence (Over 1 year ago)
Yes, people have suggested uploading from online photo sources like SkyDrive (soon to be renamed OneDrive) but nothing has been officially announced so far.
Here are a few of those earlier discussions: | |

Regarding you not being able to sign into the SkyDrive app on Windows, that's certainly not normal. 
I've read recently that some people have had trouble signing into some Microsoft services/applications when they had 2 factor authentication turned on on their Microsoft account.
Example 1:
Example 2:

Perhaps you can create an app-specific password for SkyDrive as the Photosynth team suggests?


Regarding Photosynth's mobile app they are planning new apps when they move the preview site to be the main site later this year.
andyc1202 (Over 1 year ago)
Thanks nate

The problem with the bk one is that it cant determine the focal length and i am to leave the exif data alone........never touch it i swear....

some 28 were omitted

the car one, well again focal length and not enough overlap now i found out i can click on the omitted link to see the pics!!!!!!

As you said, a lot of car in it..Thanks for the debug info. very useful. I like the cloud option (c) takes a bit of getting used to flying around it though but if i got a good synth (like my teco walk the point cloud is exceptional hehe)

I will have a look at it more tomorrow as my gf is on skype and takes priority sadly (only joking love if u ever read this)

Could you have a look at AND 
andyc1202 (Over 1 year ago)
and this one of a kitchen

(200 photos, 145 and 146 repectively.)

for both of these i followed the instructions on the vid. bedroom stood in corners and took pics all around, kitchen i stood middle and either end and swiveled both at height and down low so it could plot a lot.
then the other bedroom i started in a cornerr as a panorama then i just moved around to another position to take another panorama - taking lots pics between positions to follow my route, lots of overlaps.

In all cases, fail!!! 20 odd synthy.. The overhead doesnt have the full room, just the group of pics it starts on.

So how can i get one of these to work???
I will try outside tomorrow so there is more detail and see what happens.

I want to master this art ;)

Thanks nate for your help - as a fellow user, i appreciate it.
Any other input welcome, but 5 stars to nate so far.

Happy shooting all!!
Slyneko (Over 1 year ago)
I'm certainly not as versed as Nate but i have been shooting and looking at lots of spins.  I second the wider angle comment on your car synth.  some things i've observed:

- keep as much of the subject in the frame as possible.  It obviously helps for overlap but as Nate mentioned, background helps.  In spins with loads of background objects/features you'll notice that those features result in less artifacts than the central object

- maintain the central point.  This is mentioned in the shooting guide but i think it helps more than people realize.  I do a lot of turntable spins which is a whole other challenge but in your second synth it looks like not quite having the same real/imaginary point in the center of each shot may be a factor

- reflections can wreak havoc.  there are advanced algorithms that can separate out reflections but this preview doesn't go that far.  in both of your cases i think this is biting you.

looking forward to your next attempts!
Slyneko (Over 1 year ago)
with regards to the dropping of photos, i've noticed some weirdness as well.  i usually have success getting the full 360 but in the examples below i fall short.  in some cases i have re-shot with the same results.  In some cases photosynth tells me that some pics were omitted and in others it doesn't even tell me that yet does not include them in the final build (even from original to re-shoot).  So some subtle thing may be weird there.

I'm shooting basically in macro on a turntable with a paper background (with some texture) so i'm certainly making things difficult on the software.  Combine that with the fact that i am synthing origami models with some thin edges and overall i'm very impressed by the capabilities of the preview!
andyc1202 (Over 1 year ago)
Hi slyneko

nice models ��

with regard to my second example the cup on the table was the center of every pic i took. The compiling has made it off centre not me.

just took load more pics but on mobile so cant upload at moment. Have to wait till on desktop pc before can complete it. This is where an app to upload them to photosynth server for compiling would be good �� 
i will post update later. I have made public some of my other synths for critique 

happy shooting
NateLawrence (Over 1 year ago)
@Slyneko, hi! Thanks for sharing. =) 
I think your third spin synth above wants an additional "3" on the end of the URL.


Hi again, Andy.

Of your two bedroom synths the first one was pretty rough going with the photos. 

I think there wasn't enough light in the room for your phone's camera and there ended up being lots of sensor noise and motion blurring - neither of which will help with synthing. 

Unfortunately, they seem to be out of focus in a lot of cases too, but maybe that's just the sensor noise getting in the way from the low light. In any case, more light is probably best for taking photos with your 625. 

Also, 640 x 480 is a bit low on resolution, really. That makes for 307,200 pixels per photo which is roughly one fifth of what Photosynth uses for matching photos together.

I'm not saying that low resolution photos can't ever make a good synth, but especially when beginning, I'd give Photosynth every advantage you can.
NateLawrence (Over 1 year ago)
Check out EdLee's excellent Santa Barbara Courthouse synth for an example of low resolution photos working great in the hands of someone who has learned the ropes with Photosynth.

I'm going to link you to the Direct3D viewer, as that is the original Photosynth viewer and is much better for point clouds than the Silverlight viewer, however since IE 11 came out you'll have to do one thing to use it, which is: 
1: Press F12 to open IE's dev tools.
2: Unpin the dev tools from the tab they open in. (You should only have to do this step once.)
3: Go to the Emulation tab (lowest on the left of the dev tools) and change User Agent String to Internet Explorer 10.

Then you can minimize the dev tools or just click back on IE and in that tab, you should be able to follow this link if you have the Photosynth desktop app installed:

Keyboard shortcuts for the viewer: Page 10
NateLawrence (Over 1 year ago)
My apologies. It should have been this link for Ed's synth:
I also have to point out that he did take higher resolution shots and then downsample them. I'd still love to see him synth the originals.

In any case, the higher resolution shots in the second bedroom synth were a real step up, although there's still some motion blurring happening. That's going to be a challenge for you if you're shooting handheld and can't get more light in front of the camera. I would have suggested using your flash, but I see that in some shots you already are.


As far as a different method of actually shooting an original photosynth, my approach may be a bit mechanical for some, but it should work for you.

It basically boils down to using the synth types found in Photosynth 2's preview, but shooting them intentionally to link to each other.

My favorite is what we now call a Spin.
NateLawrence (Over 1 year ago)
For the bedroom, I'd want to orbit important things in the room like the bed, the dresser with the mirror, the dresser with the projector, the bookshelf, the clothes hamper, the wardrobe, etc.

After you've shot a good spin of those types of things, what you've done is teach Photosynth how to recognize any of those things from all sides you can walk to, so the only photo which sees those things that won't link to at least one of the photos in the spin of that thing is one which is far enough away that the size difference is too big of a leap for Photosynth to make.

If you have room, you could shoot one or more additional orbits of any of those things, moving further away with each orbit.

Alternately, you can just shoot what we call Walks in Photosynth 2 between your spins that teach Photosynth how to get from the Spin of the bed to the Spin of the dresser with the mirror.

With large flat surfaces like the dresser top, I'd shoot what we now call a Wall synth.
NateLawrence (Over 1 year ago)
You may be realizing that shooting a synth as I would is starting to look more like using your camera as a 3D scanner and scanning the room. That's pretty much correct.

You may object that on its own, that is a bit mechanical and I'd have to agree with that as well.

What I'm trying to teach you is how to get a point cloud of the entire environment to hang together in the primary photo cluster. (This means, you should see everything grouped together in 2D view or the point cloud of the entire scene in Overhead view.)

After you've done a this base scan of the environment, you'll want to actually shoot a little tour of photos which you actually hope that will interest people (instead of walking in circles around everything in the room, which likely won't get too much applause).

Whether your tour consists only of individual shots of different things in the room and added as Highlights, or whether it looks more like a walk through the room is up to you.
NateLawrence (Over 1 year ago)
Check out Swami World Traveler's rad scavenger hunt synth here for an example of how to really make a good reconstruction interesting.

Silverlight: (Highlights + Overhead view)
Direct3D: (Fast, smooth, great point cloud experience)
NateLawrence (Over 1 year ago)
With the kitchen, I'd have similar suggestions. It's a challenge as it's so narrow and the walls are big and blank.
I would want to orbit things like the stove top, the utensils, the sinks, the dish drainer, the microwave, the light switches, the fire extinguisher, etc.

Again, higher resolution photos and less motion blur will help you here.

Things like the countertop and the wooden cupboard doors below the sink make me want to shoot big wall synths (remember, lots of overlap) and I think that in this constrained space that a Walk in both directions with a Panorama at each end to link the walks to each other would probably help.

Things like the sinks and the microwave are not synthy, so you'll be relying on the pattern on the countertop around them to hold those photos together.

I really liked your lower photos in the kitchen. I'd love to see a Walk shot in both directions from both child height and adult height. I think it would really add a cool perspective.
NateLawrence (Over 1 year ago)
What this all comes down to is just thinking about what the Photosynth Shooting Guide is telling you for Photosynth 1 and the Expert Shooting Guide is telling you for Photosynth 2.

If you haven't watched them both, also watch the video tutorials: 
Photosynth 1: } Photosynth 2:


When most people hear to overlap their photos for Photosynth, they think about overlapping the sides of the photos and another way of saying what I said above is that I think more people should be thinking about overlapping the center of their photos first.

It's true that for shooting parallax Panorama style synths or Wall synths that you'll be overlapping the sides of the photos, rather than the center, but I think that people should begin with shooting spins and walks, as that teaches you the sort of overlap that's important.
NateLawrence (Over 1 year ago)
Remember that Photosynth can only:
1) make a point cloud of the things that it sees in multiple photos
2) calculate depth properly when it sees the same thing from 3 unique camera positions
3) link the photos to each other if you don't move too far around an object between photos
4) link the photos to each other if you don't move toward or away from an object too far between photos.
NateLawrence (Over 1 year ago)
Other tips: 

No matter what sort of synth you're shooting, intentionally thinking about tracking and overlapping both foreground and background with your shots will help it lock the scene together. 

If either the foreground or background is not synthy (like a glossy plain white porcelain pitcher or a shiny car with a single flat color paint job for foreground or a blank wall or cloudless sky for background) you will have to rely on what's visible in frame (which may not be the point of the photos, such as the pavement or grass around a car at a car show) to hold the synth together.

Repeating patterns will be a problem for Photosynth unless the surface that the pattern is on is non-uniform (your blanket is a good example: the pattern repeats, but the wrinkles make each iteration unique). Dirt on the kitchen floor tiles also helps distinguish them from each other.

Overall, think about shooting mini synths in a scene, then shoot mini synths to link them together.
andyc1202 (Over 1 year ago)
Nate, You are a star, Thank you for your time.

I haver just found a photo app that allows me to take 2048*1536 so gona try that shortly.

So what you are saying is that is doesn't matter where I start in a room I need lots of overlap. which is what I've been trying to do......

I did one today  ... interesting!
I  started with a spin in the middle. It was a car park. one end cars were parked with a wall and a street behind, either side two walls and the other end was the entrance with a cherry picker parked.
in some ways it works well, but looking at the point cloud it has really mucked some of it up. (I tried your link for the keyboard shortcuts but it wont load! - can I bring up the camera view in the viewer?) - im in ie10 and have chrome available too...

Ed's couthouse is excellent. kudos to him. That's what im after.

The mechanical way you mention is what Ive been trying.
andyc1202 (Over 1 year ago)
Ill have a go in a minute again. 
I start from a point and do a panorama then take a walk to something and do a wall or a spin around something then walk to my next point. I am trying lots of overlap and am confused as to why it isn't working. I will try the new photo size and more light in my next attempt of my room (just cos its easy as im here)

Yep the Hiroshima is excellent, having been there years ago it brings back memories as well! :)

SO if I treat doing a synth like I do the new synths, walk, wall, spins - and link between them with lots of overlap it should be ok?

That's what im off to try now :)

Let you know shortly. thanks again Nate
NateLawrence (Over 1 year ago)
Glad to help, mate.

Sorry to hear you're having troubles getting the Photosynth Guide (with the shortcut keys for the Photosynth 1 viewer on Page 10) to load.

Try going to this page: and getting the PDF or XPS.


Since you're using IE 10 instead of IE 11, then you can skip the F12 bit above.


Regarding photos' order, as far as Photosynth 1 (the desktop app) no, it doesn't care about the order they were shot in. It's going to compare every photo to every other photo before it's done, so it's really all about showing Photosynth how to get from one viewpoint to the others with your camera.

I would caution that if you're shooting for Photosynth 2, though, (the Technical Preview) that the order shot does play a part in how a synth will play back, so keep that in mind as you shoot for each.
NateLawrence (Over 1 year ago)
I know it can be rough when you've taken a couple hundred photos and had things fall apart, but I think that you'll be happy if you hang in there.

Looking through your photos in named order, I can see you going for the overlap + you've got the right idea, but in some cases need to slow down a little moving around things + others just need more light.

If you still can't get the Photosynth 1 guide to load, here's an image of the shortcut keys page:

Here are the important ones:

In the synth, be sure to use the [P] key to toggle between:
Photos Only
Photos + Point Cloud
Point Cloud Only

The full stop [.] and comma [,] keys will take you forward or backward through the photos in alphabetical order.

In Point Cloud Only mode, use the [W][A][S][D][E][C] keys to move around and [{][L][:]["] keys to look around.

The [Enter] key will fit the photo to your screen.

Use your scrollwheel to zoom.
NateLawrence (Over 1 year ago)
Looking forward to seeing what you shoot this time around. ツ
andyc1202 (Over 1 year ago)
Hi nat. Thanks for that. Ill hang in This has gone quite well, but a compiling error has done weird things. cars at one end, cherry picker at other, wall with windows one side and wall with door the other, so a squarish car park. Behind the cars there is a street over the wall. not sure what happened. thought it was all pretty good.
just synthing bedroom, report back shortly.
andyc1202 (Over 1 year ago)
as for the one above - - - 95% synthy..... surprised as it misplaced a wall and one end of the car park!!!!!!!
 heres part of that in a walk which is good heres some more 

heres a wall set I did as well, you can see how it doesnt like the car bonnet (blue car)

As for my room, 65% synthy now working on it. The point cloud is excellent and overview is spot on. It doesn't like the wardrobe I think.

Uploading one more to try it then I will try some outside buildings tomorrow.
andyc1202 (Over 1 year ago)
here it used 24 out of the 39 photos for this walk from what im using in my synth <- finally !!!!! :)
not bad 90% synthy!!!
NateLawrence (Over 1 year ago)
Very cool, man! ^_^ Glad to see you finding success.

Keep it coming, but don't feel bad if some synths in the future still fall apart. 
Even those of us who have been shooting them for a while still have things fall apart on us now and then. 
You just have to sit down at that point and think about why something didn't link (or just ask - we'll all be here, ready to talk).


As far as the synthy score on the car park, Photosynth can't tell when it's arrived at a correct or mistaken answer, so the percentage just refers to the percentage of photos which linked to each other (regardless of whether those links are correct or not).

For a more technical description, I'll point you to Nathan Wilfert:
NateLawrence (Over 1 year ago)
Since you seem to be pretty interested, I'll point you to your Photosynth log files, which help when figuring out which files matched into the main group and which didn't.

In any 'Computer'/'Windows Explorer'/'File Explorer' address bar (not Internet Explorer, mind you), type the following line: 

In any log, search for "Synth 0" to find the list of photos in the primary cluster.


Once you start generating point clouds you may want to download them and view them locally.

You can use either SynthExport by Christoph Hausner or PhotosynthToolkit by Christoph Hausner 

They'll only download Photosynth 1 point clouds at the moment, but Christoph is working on adding Photosynth 2 support. 
Henri is actually making the Photosynth 2 viewer, so he won't be updating his toolkit.

For viewing the point clouds, MeshLab is one free 3D model viewer.
NateLawrence (Over 1 year ago)
Oh, one little tip that I meant to mention earlier: If you want your name to appear next to the copyright symbol on Photosynth 1 synths and panos, you'll need to add your name to the 'Author' field in your photos' metadata.

Don't worry; this won't alter anything that Photosynth uses to put things together.
andyc1202 (Over 1 year ago)
Thanks Nate.
i shall get to work on some more. I am very interested in modelling buildings like the couthouse, in and out. I also saw a country house near London in a synth that worked exceptionally well. That's my bit to master. I got the hang of the walk, wall and spins and understand what its grabbing now to link photos so i can rectify problems there easily enough.
thanks for info on log files and all that. I will have a look tonight when at pc.
cheers mate.
andyc1202 (Over 1 year ago)
Taken a nice walk today through a canopy walk in a supermarket car park, that then kinda turned into a full synth ��cant wait upload it. Bring on the mobile apps ��������
andyc1202 (Over 1 year ago)
hi, question, i cant get a point cloud for this
NateLawrence (Over 1 year ago)
Hi, Andy,

Sometimes if the point cloud is a little larger it may take a while to load in the Photosynth 2 viewer.

Usually if you give it 30 seconds to a minute to load and then exit global camera view and enter it again, you'll see the point cloud drawn.

That was my experience just now.


From what you say, I'm sure you've already tried the following, but for others, remember that the default option for the point cloud in Photosynth 2 is for it to be turned off, so if you ever use a different browser or different computer (or even the private mode on the same browser on the same computer) you'll need to turn it on manually in the debug panel again.
andyc1202 (Over 1 year ago) NOT BAD.... have a look at coments save write them here again if you wouldnt mind Nate.

Yes it was just loading time with point cloud. Im running via my mobile phone 3g signal for data :(
Slyneko (Over 1 year ago)
Glad to see you are getting better results Andy!  I'm finding it fun to watch how you are utilizing the results of your photo sessions in both photosynth 1 and 2 and the way you break things up into different styles of version 2 synths.  really showing the pros and cons of the different approaches taken by the team on version 1 and 2.
NateLawrence (Over 1 year ago)
Agreed with Slyneko! Your room synths in Photosynth 2 are definitely unique. =)
Some of your car park synths worked really well in PS2.

Regarding your Sainsbury's 1 synth
There are definitely portions of it which hold together well, but as a whole, much less so.
I'm sure that's not much fun to hear, but you've already acknowledged that the inside didn't quite align as you'd hoped, so I'm sure it's not news to you.

You've already pointed out the sun flare getting you a bit in the comments as well.
Although it's there and not ideal, it doesn't actually seem to have been an issue except where the upper left corner actually has the sun in frame + has that quadrant washed out which fractured you several times. 
If you're ever in a situation like that again + don't have a sun guard of any kind, I'd go for risking getting your hand in frame to shade the lens, rather than getting the glare.
NateLawrence (Over 1 year ago)
Going through doorways is always something to be handled with care in a synth, simply because so much of what is in frame changes as you do. The same applies to when you near and pass the shopping cart return bays.

Whether this just amounts to slowing down at doorways to get more images of the transition or you actually do a bit of spot welding/soldering using shots of the ground which you then tie back to surroundings on both sides of the doorway is up to you (at least in Photosynth 1).

That big reflective glass entryway is definitely a challenge, however I would point out that it offers an opportunity to tie images from the entryway back to the outdoor views that you took just outside that front window looking back toward the car park, crosswalk, and canopied walkway which was not quite seized upon.

I would definitely have wanted to get as close to the inside of the front window as possible to tie back to the crosswalk (store personnel permitting).
NateLawrence (Over 1 year ago)
You appear to be correct about the red sign outside the exterior left and right doors matching each other.
Repeating/symmetrical architectural features are definitely something to watch for.

The way to overcome them is by finding unique surroundings and highlighting that and/or building a strong bridge between the duplicate features that pushes them apart in the reconstruction.

The large wooden facade behind the two signs ought to do quite nicely, actually (you can see the wood already coming through in the point cloud).
NateLawrence (Over 1 year ago)
For me, I feel that the entryway is where everything falls apart. 

I see the walk that you took in there and the panorama(s) from inside it but then the walk into the store via the interior left doorway is a bit too sparse and there's one quite blurry frame in a critical juncture there.

Your spins of the front displays and the pano between them were good instincts as well, but they aren't strongly tied back to the entry which, in turn, is not strongly tied to the exterior shots, so everything floats apart at that point.

I know what it's like to just shoot when you're actually at a location (I had a very similar experience shooting a concert venue a couple of years back) but if you reshoot, I'd try for a time when the sun won't be working against you so aggressively.

If it was safe, I'd want to shoot a wall across the front of the store from across the driveway to separate those two signs and also shoot a walk approaching + entering the exterior right door.
NateLawrence (Over 1 year ago)
One little technique that I use to lock two walks together if I'm shooting the walk in both directions is to do a spin of a spot on the ground at each end. 
This generally works because a walk will have had that point on the ground in several shots as you neared that end of the walk, but you can purposely shoot some shots looking down from the end of the walk to the ground, just to be sure.

I can't say I'd recommend it for Photosynth 2, necessarily, but it works great for building structure + making sure things connect. In this case, if you were to shoot walking back down the length of the canopy from the store back to your starting point the crosswalk would make an excellent place on the store end.

I'll use the same technique for getting two sides of a doorway to lock together if I'm concerned that the shots walking through may not be enough.
It's easy enough to look from the surroundings on either side, shoot a walk to the floor of the doorway, + pivot through.
talentgate-copt (Over 1 year ago)
How I do spin photosynt please??
NateLawrence (Over 1 year ago)
Hello, TalentGate-Copt, 

I looked at your profile and see that you are using Photosynth 1.

Your 'Vlasek 2' synth is shot as a spin, however because some of the photos were blurry and because the background does not overlap as much as it should because of the 'portrait' orientation of the camera and the proximity to the subject not all of the photos could match.

You can still rotate through the photos which did match by clicking and dragging left and right on the arrows that appear.

If you would like to try these photos as a Photosynth 2 spin synth, please use the Photosynth 2 upload page at


Also, your 'Vlasek3' synth is shot as a 'Walk' synth. 
In Photosynth 1 (as it is currently uploaded) I suggest using the period key [.] to advance through the photos.

If you wish to upload it as a Photosynth 2 'Walk' synth, use the Photosynth 2 upload page.
bknapp (Over 1 year ago)
Could you take a look at this 360 deg spin synth?

I'm not sure what I am doing wrong. Technical preview says it omits 28 of the 57 files because:

  ◦We couldn't determine their focal length. Preserve EXIF information in your photos before uploading them.
  ◦They were shot before or after the looped path that was detected.

The shots were all taken in order, approximately equally spaced and I haven't touched the EXIF data. Any suggestions would be great. I've tried it a bunch of times without success.

Here is a zip file with the original images.!758&authkey=!AApuM2fdBLRkh88&ithint=file,zip

Very kind regards,
Nathanael (Over 1 year ago)
Hey there, Byron,

The bottom line is that Photosynth 2 is having trouble finding things in your images to lock onto or track between images.

Since your photos are all essentially the same focus and distance I can't account for why it succeeds with 29 of 57 but fails with the remaining 28.

Since the 3R itself does not contain very many trackable features, you're probably going to have to depend on the backdrop for this synth to succeed.

Using a less bright exposure may help Photosynth to track your schematic more successfully if you're determined to use that as your backdrop for visual reasons.

I tried your photos in Photosynth 1 out of curiosity and it matched 56 of 57 photos:

I haven't yet checked to see whether the computed camera positions look correct.
With a set of photos like this there is a danger of symmetry providing false positive matches.
Nathanael (Over 1 year ago)
My primary suggestion is to use a different backdrop such as a wooden table or workbench or anything with more dense details and less nearness to symmetry.

You can use the [P] key on the Photosynth 1 version to view the point cloud and understand exactly what parts of the photos Photosynth is succeeding in tracking.

The error message about preserving EXIF information is almost always a false one for me, so don't pay that any attention.

As to the photos being shot before or after the looped path, this just refers to a common problem in shooting an orbit of photos around a subject where many people 'overcomplete' their loop and their last photo(s) overlap their beginning photos.

I don't believe this was actually the case in your set, but if Photosynth is struggling with symmetry on the print then as it attempted to process your photos in sequence it would have interpreted the second half of the spin as a second pass around the first 180° and excluded them.
Nathanael (Over 1 year ago)
Byron, after taking a proper look at your Tech Preview Spin synth (sorry, I went straight for OneDrive earlier) I would have to say that there is definitely some false positive matches happening from the schematic. The part of the diagram that shows the array of holes on the interior of the blockhead on both sides of the paper is highly attractive to Photosynth's image feature tracking and matching.

What I didn't expect was that Photosynth 2 would believe that it has succeeded in solving a full 360 degree spin while leaving out half the input images.
Type [M] on the Tech Preview synth to pull up the overhead map of camera positions.

I thought it would be a case of correctly reconstructing a semi-circular spin and breaking at some point in the path, but that was a false assumption.

Both versions of Photosynth, though, are solving for the camera path at an odd angle to the paper's surface.
I have to just chalk this up to needing a backdrop with more visual texture.
Nathanael (Over 1 year ago)
I also tried your photo set in AutoDesk's 123D Catch ( ) to see if it would fare any better.
You can view the resulting mesh here:

As you can see, the blockhead itself eludes the current algorithms' ability to track it.

I'm not suggesting that you do anything that might endanger your expensive machinery, but I can tell you that if I had an inexpensive object with that appearance, if I coated it in a powder of some sort the computer should immediately be able to track its shape.

Finding a better backdrop is by far the more preferable method, however, even if it doesn't yield geometry for the blockhead itself.
bknapp (Over 1 year ago)
Thanks so much for your time and expert advice. I'll try it again with more a "sythy" background.
Very kind regards,