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jocco
03-17-2011, 02:51 AM
Hi Guys

I'm lookin for a quick and effective way to match the camera to a photo. Lets say I got a picture from a heli were I need to compose a buildingconstruction in.

I know there is the taft camera match plug-in. I watched the video on their site, but I assume that this plug-in is only good when you have some references of objects on the photograph.

I know that there is a cameramatch solution in 3Dmax, is there something included in LW10 (I don't think so, could'nt find it in the manual anyways ...). Does anyone now something is like that is coming in update of LW10.

If anyone can share some tips, plugins, workflow, I would be very thankfull

drako
03-17-2011, 04:18 AM
jocco if your photo has metadata informations you can use the real lens camera and you can choose the model of your camerra or your lens but the better way is to choose the
camera from image and then you have everything applied in your LW camera..
cheers

jocco
03-17-2011, 04:48 AM
thanks for the quick response. but I don't understand the difference between 'metadat from the photo' and 'camera from the image'.

and what about the perspective ? Do I have to do this manually ?

zardoz
03-17-2011, 06:00 AM
usually I use this plugin
pretty good
Note: with plugin window open use shift+alt+lmb to pan and shift+alt+rmb to zoom
http://www.lwplugindb.com/Plugin.aspx?id=c71a8c69

Andy Webb
03-17-2011, 06:21 AM
usually I use this plugin
pretty good
Note: with plugin window open use shift+alt+lmb to pan and shift+alt+rmb to zoom
http://www.lwplugindb.com/Plugin.aspx?id=c71a8c69

Shame there's not a 64bit version of this plugin.

Just tried the camera from image and it only picked up the pixel size, no camera info like lens ect.

I checked the image and the information is there, is there something I missed?

Cheers

drako
03-17-2011, 10:05 AM
first you have to fix the lens of your LW camera for matching everything.
Metadata comes with the image of your camera.For example a usual Fuji Finepix or Canon gives metadata...
information here
http://en.wikipedia.org/wiki/Metadata
For example
In the camera properties you choose Real Lens Camera and then under the lens focal
length you click the dropdown tab and you choose from image.With the metadata info
LW is matching everything.
This works fine when you have metadata info from your image or your shot.
So if you know the lens thats even better for matching exactly.
When you finished with all that and you start matching your building in the image.
Remember that first you match the lens of your LW camera with your real Camera and
then you start matching your objects inside your scene.
J espere que c etait facile pour toi....:)

dwburman
03-17-2011, 10:18 AM
The Taft plug-in uses a fairly manual setup process. It's been a long time since I tried using it, but I wasn't able to quickly get results I was happy with. Since I was just trying it out and not using it for a job, I didn't make the effort to learn it.

Andy Webb
03-17-2011, 10:33 AM
The problem I'm having is the Meta Data seems to be there in Photoshop but not in LW.

The only data available in "Use Image" is "Use Width & Height".

Looking at Meta Data in the LW image editor shows nothing, other than
Aspect 1
Black Point 0
White Point 1
Gamma 1
Exif Color Space Uncalbrated

Andy Webb
03-17-2011, 10:38 AM
This what I'm getting in Photoshop.

jocco
03-17-2011, 11:59 AM
Thanks for the replys guys.

@Drako: Allright I can see what you mean by image !
I've got a Nikkon D90, lens Nikkor 18-105 mm
This is not available in the presets, so I have to go with the 'from image option'

I''ll give this a try and see what I get with your advice

thanks

jocco
03-18-2011, 08:46 AM
Hi Guys,

I'm playing around with some photo's and planes.

I'm using the 'from image' option.

The result is far from perfect. I'm wondering about the placement of the grid in relationship to the horizon in the photograph. Maybe someone can take a look ro see if I'm doing this correctly ?

cheers, Jocco

another questions that pops up: do you have to take the disctance of the object to the camera in real into account when matching in LW or 'only' get the right perspective and make the match so that the sizes fit ?

drako
03-18-2011, 01:32 PM
its true that you have to manually eyeball match your objects in your scene with your image.But fixing and matching the grid in the same perspective as your image that is necessary..
Yes its true that is better to know all the informations needed about your scene for example distance of the camera and the scale of real objects.Camera match is a very
difficult and expensive work for achieving the photogrammetery.
If you cant arrive in the result that you want then you have to cheat.
If you cheat then you are going to see some tools i refer here..

http://www.worley.com/E/Products/taft/camera_match.html
http://www.lwplugindb.com/Plugin.aspx?id=c71a8c69

last i refer this plugin that allows you to move points in the layout for correcting your
geometry according your image

http://www.lwplugindb.com/Plugin.aspx?id=55278d60

JonW
03-18-2011, 03:22 PM
What I do for my photo montages is put the BG photo in Modeler as a background image in the display. Trace the key things like existing buildings, power poles, edges of footpaths & the edge of the BG photo. These outlines I save as an object.

In Layout I attach this object "Outlines" very close to the camera & scale it down in size so you can see more or less all the outlines. Then I move the camera position so that the outlines match up with these same objects which I build as simple surrounding objects, these objects are usually on the survey.

Once the camera is in the correct position, make it the correct focal length so you see the edge of photo outlines & if you are rendering the BG image as well, position this so it fills the camera view.

If you use a zoom lens its a good idea to correct the image to remove lens distortion.

Also where you can, when on site when you take your photo for your montage make a note of the camera location or better still measure where the camera is located & keep the camera perfectly level, get a level for your camera. Its not necessary to measure the location but I find it easier & less time on the computer. Obviously an image from the air in general you will have to guess the camera position.

I always give the architect a copy of the montage with outlines so they can see things have been lined up correctly. A lot of jobs end up in our Land & Environment Court because the new developments in general get complaints from others.

JonW
03-18-2011, 08:06 PM
In the camera properties you choose Real Lens Camera and then under the lens focal
length you click the dropdown tab and you choose from image.With the metadata info
LW is matching everything.
This works fine when you have metadata info from your image or your shot.
So if you know the lens thats even better for matching exactly.


I don't know what I'm doing wrong but in my above example I'm using a Canon 14mm (FOV 104 x 81) on 5D2, but I need to put "8.8mm" in LW for the camera to have the correct perspective, whether the perspective camera or real lens camera is used ???

I have just used my procedure over the years & in the end stuck with perspective camera, but the focal length never matches LW's focal length, something is wrong somewhere, either LW or me ??? It would be nice to solve this one, although it works fine with the different focal length (14mm = 8.8mm ?)

My procedure above is simple & with a tape measure on site I have never had a problem.

One example of bubble level, there are many others, plus a new 3 axis level.
http://www.the-digital-picture.com/reviews/Bogen-Manfrotto-337-Hot-Shoe-Double-Bubble-Level.aspx

jocco
03-19-2011, 06:52 AM
I have just used my procedure over the years & in the end stuck with perspective camera, but the focal length never matches LW's focal length, something is wrong somewhere, either LW or me ??? It would be nice to solve this one, although it works fine with the different focal length (14mm = 8.8mm ?)


I've got the same experience. I always tried to use the metadata and the perspective camera, but the results never matched at all and got me all confused.

Thanks for the tips guys, I'll go on experimenting tryeing to get a efficient workflow.

XswampyX
03-19-2011, 10:27 AM
I don't know about any of the technical settings for your camera, but I can tell you that the slabs on the left are 600mm x 600mm in size.

Just model the slabs and then change you camera settings to match?

Axis3d
03-19-2011, 09:34 PM
There is a 3rd party software called SynthEyes. It is mainly used to create a 3d matchmove from moving footage and will output a Lightwave scene file to match moving camera footage. I've used it on many projects and films.

It also has an option to create a camera placement for a still photo. You provide it with some information by drawing lines on your image (representing x, y, and z parameters) and it will attempt to create a camera in 3d space. You can then output this as a Lightwave scene file.

Netvudu
03-20-2011, 05:40 PM
be sure when camera matching that you dont work with a cropped image, otherwise it gets almost impossible to match the shot accurately

scenicdave
03-20-2011, 10:56 PM
Hey Guys,
Firstly, SynthEyes is completely awesome, cheap, and will solve all these problems easily. Further, it's made by Russ Andersson who has taken the trouble to fully and carefully document the process and the pitfalls of matchmoving, on his website and YouTube channel. It's done so well that you should spend an evening there whether you buy the software or not. Really worthwhile. (Do it **before** you shoot anything)
http://www.ssontech.com/

Secondly, Worleys Taft collection Camera Match plug-in works really well, but is significantly older, harder to use and more complicated. It's for stills only though I did once solve multiple frames for an animation. It requires access to accurate measurements of the site, and requires you to build stand-in objects. It also requires laborious manual inputs in Layout. Having said that, it works very well and has saved me in the past.

Thirdly, is my own simple technique well suited for architectural stills.
Shoot the site, but take specific note or where you stand when you shoot. I usually snap a few shots of the surrounding footpath or garden wall etc. Then you're back at the ranch, fire up Google Earth and take screen grabs of the place. You may need to comp a few together in PhotoShop. Map it to a plane, taking care to get the aspect and scale right.
(Use Google Earth to get a few measurements of roads widths etc)
Now, put this plane in Layout and position the camera exactly where you stood to take your photo's; calculate the rough height too, (were you standing, tripod, or in a tree, balcony etc). Put your 3d building/geometry exactly the right size, in the right place on the Google Earth map. Orient the camera correctly as per your photo. This alone will get you 90% the way there. Spend an hour dicking around to get it nearly perfect.

This sounds very simple but it works remarkably well. I'm assuming you're moderately advanced in LightWave and can get things like scale, lens distortion and camera rotation right.
One thing I've learnt about matchmoving is this; there is no perfect solve. If a solve looks right, but is giving the wrong numbers, don't sweat it. Trying to get a good solve and comfortingly accurate numbers is a goose chase.
Finally, be prepared to distort and morph a little in PhotoShop to fix those last few details!!
regards
Dave Tracey
Sydney

jocco
03-21-2011, 03:29 AM
Thanks again for this valuable information and tips. I'll check this all out and keep searching!

thanks, Jocco

alexos
03-21-2011, 08:41 AM
I've got the same experience. I always tried to use the metadata and the perspective camera, but the results never matched at all and got me all confused.


You have to take sensor size into account and, for some reason, LW doesn't always get that right. I usually grab the lens focal lenght from metadata and input the sensor size manually - if your camera is full-frame, just type 24 mm in the "frame" field of LW's camera panel. If it's an APS/C check the camera's specs (they're never exactly the same size) or, well, just keep the full-frame sensor size and multiply focal lenght accordingly.

ADP.

Lor
03-25-2011, 11:49 AM
Jocco, getting a perfect (or close-enough) match is one of the more complex tasks we have to do in VFX. Critical to a good match are:

-a moving shot with parallax (sideways or up-down movement). If it's just a still, you should be able to "fake" something that looks good enough.
-as many measurements as you can get including
-distance from camera to objects
-size of as many objects as possible
-focal length at the time of shooting
-filmback (size of recording medium)

Note that a lens focal length on it's own is useless. You MUST know the filmback as well, as filmback changes the Field of View, sometimes significantly.

Ultimately you will use a tracking software like Syntheyes or a photogrammetry software like Photomodeler to establish the bounds of your scene geometry. If you know the rough dimensions of some buildings nearby, make boxes to that size (remember always to work in real world scale) and place them according to your measurements. You should then be able to position the camera so the grid closely matches perspective in your scene.

Again, this process is not for the faint of heart or the inexperienced working alone. It requires expertise and patience. Especially patience if you are attempting this for the first time.

Good Luck!

lor

jocco
03-25-2011, 01:33 PM
Again, this process is not for the faint of heart or the inexperienced working alone. It requires expertise and patience. Especially patience if you are attempting this for the first time.

Good Luck!

lor

thanks for the advice and the encouragements. I'll just dig in and do the best I can !

cheers, Jocco