scene matchup with photograph

[percydaman]

Any of you pros do alot of camera matching with photographs without knowing dimensions? If you do, I could really use some pointers. Definitely could use some more experience, but I can never get my scene to match the photo exactly. Since I dont know exact measurements, I cant really use camera match utility. Or can I?

[thablanch]

The following work is a good explanation, not by me

http://www.seraph3d.com/tutorials/compositingtut02.htm

Not really a pro, did a little only.. but I'm never using camera match, and usually, grid lines plus lines drawn on the picture to match does the job..

[cocolas]

most of my comps are w/out me knowing exact dimentions of stuff in there...but often if you study the pic you'll find something that you can al least relate to in size...a door/window/street sign,car...anything like that....

and as Tim's tute points out, a big helper is drawing the horizon and a few main perspective lines on a copy of the photo...then take that in the max viewport background and go from there...

post the pic you need to match, so we can have a look....


paul.

PS: also for matching mats and lighting it REALLY helps to render in layers out of vray...so you can control every single aspect in post and tweak it in real time till it's just right.
at least this method works really well for me....

[gitano_anton]

I´ve done some photo-montages. It´s imposible to match totally the model into the photo with only 3dsmax. The most part of work is in Photoshop.

[percydaman]

Ive seen that tut on seraphs website, and its great, but I was kind of referring to indoor shots where you cant really see the horizon and such.

[cocolas]

you can always figure out where the horizon line is, by drawing your major perspective lines (say from where the ceiling/floor meets the wall, or other furniture alligned with that....etc)
where those lines meet, you'll have your vanishing point/points, and therefore your horizon.....even if in the pic is not necessarily apparent.

if you post a pic we can take a look and give it a shot/some suggestions...



paul.

[trixian]

You might want to "unpinch" the image before trying to match perspectives. Wide angled lenses show alot of curving, and very cheap lenses sometimes have non-uniform deformations. If thats the case...you wont get a good match.

Try using the filters under distorsion in photoshop for this. If its a sequence, there should be some useful plugins for AE and Combustion.

[namlennon]

thank thablanch for the link.It's the answer for my question at the moment!Thank you thannnnnnnnkkk yoou!!

[sunnyc1]

If you still need some pointers, post your scene or least the photograph and I'll take a look. Very rarely are photomontages easy. It usually requires a very good eye for perspective.

SunnyC

[dellis]

Percy,

I use Syntheyes for my camera match/tracking. If you load in a sequence of pictures (not video) you can manually move points from pic to pic and it will solve for each image. WOrks really, really well....and blazing fast too.

Email me if you need some help....well if you have more then one image.....if you have just one then i can't really do much.

[Aguel]

Guys need some help here.

I will be doing a photomontage for a residential project. I will be using a digital camera for the shot. What are the things that I should take note prior to taking the shot? Do I have to measure some references i.e. post location or any other objects? Do I need to measure the distance where the camera is set up from the proposed building? How would I be able to match the FOV of the scene from the picture?

Thanks in advance

[archprog]

if you are gonna make the camera matching manually then taking at least one measurement is enough i think, for instance the height of a door. if you are gonna use the camera match utility then you need to measure some more references, for instance you set a 0,0,0 point which could be the corner of a building for instance and then start measuring from there to other places in the 3 directions.

But i think that if you are gonna take the pictures yourself then you don't need to use the camera matching utility because you will have all the info you need, fov , camera height, reference measure, picture size.

As for the fov , you need to find what is the equivalent fov to a 35mm camera for your camera model, so the fov value of the photo will be different than the one you have to put in the max camera.

here is a link about this
http://www.outsight.com/hyperfocal.html#digital

[sunnyc1]

Will you image be used for marketing purposes or for submission to the local authorities? If it's for the former then you need the following:

1) Time of day (you need to reproduce the same lighting)
2) Camera location relative to the building.
3) Relative target position (Is the focus of you image on a window 2m up in the air)
4) Take note of your lens. Are you using zoom?

If your image is for the authorities I recommend you obtain some survey data. I've had numerous occasions where my client has been taken to court over the developments and the images we produce must be accurate and certifiable.

1) Survey drawings showing roads, existing structures on site
2) The survey should also provide heights of neighboring bulidings.


I've found that Max's camera match is only suitable for the simplest of sites. And when they're that simple, you don't need camera matching software at all.

You need to build massing models of either an existing structure on your site, or the neighbouring buildings. You them to triangulate the and match the photo. The data you record when taking the photo is only something to start with.

SunnyC
www.ivolvestudios.com

[Aguel]

Thanks archprog & sunnyc1

The project will be for marketing purposes. Yes the focus will be at a height of approximately 2.5m from the ground level. The camera position can only be taken at a distance of around 25m from the building position this is due to some obstructions. What will you guys recommend to use or not to use camera matching for this situation. This will be a trial and error for me as this is my first time doing photomontage.

[sunnyc1]

Can you post an image of the photo you are trying to match.
It'll be much easier to much recommendations.

SunnyC