Urgent, Need Some Professional Advice on 3d Projection

[Rockhoppermedia]

I am sorry to say if you are using CS2 it has a bug in photomerge. I borrowed my mates CS3 enabled laptop to try to photomerge and it works on that.

CS2 always gave me issues CS3 extended seems a lot more stable,

Sorry to put a damper on things

Rich

[chronic]

the process you described will not work for this shot. any kind of photo merge, as well as spherical and cylindrical mapping of environments relies on the camera rotating around a fixed point, otherwise the perspective in each shot will not line up. in your shot the camera has a dramatic movement. the only way to acheive this shot without complete modeling and rendering is to projects multiple mattes from multiple angles on the actual city geometry, i know there is a mental ray shader designed to do this in maya (cant remember the name) but you could also do it by hand.

[RiKToR]

Rockhopper its CS3 that Im using and it works well with any photos I use but not this.

chronic, but there is no real parallax movement in the background, I understand about the foregroud building but that will be modeled... I dont understand why a photomerge without compensating for perspective and such will not work? I can create multiple mattes from the key shots but at that point I run into a considerable amount of problems making sure colors are accurate from one matte to the next. Is there any other way besides fully modeling the environment?

edit... scratch that I see some parallax now at the end of the move... but still not photo merge without perspective compensation?

[chronic]

its just the nature of the beast, unless your camera rotates around a fixed point, you cannot get this to work as a single stiched image.
you might try hiding the building, placing the camera aproximately around where the character might be and making your images for stiching from that location, hopefully the slight difference in camera placement wont be too noticable from the final camera angle because the scene is so large and distant.
as for projecting onto geometry, the idea is that you would paint, for example, a building from a particular perspective and project that texture onto the geometry from the same perspecive in 3d, then when you move the camera it should be pretty good, it would take alot of work and alot of projections from different angles. you would never end up with a single seamless painting

scoll down this page, there are a few examples of how spherical projection works and projecting onto geometry
http://www.digitalartform.com/archives/3d_computer_graphics/index.html

[RiKToR]

Ok... so if I took the animated camera and picked key spots for projection and duplicated that camera at those points making the copies static for projection, your saying that from there I would make however many mattes it would take to create the final backgroud plate using the patching methodology, correct? What kind of problems could I get from this?

[chronic]

im not an expert on this stuff, i only know the theory, you are going to have to do more research and experiment alot.

i havent seen this dvd but it might be a good investment.
http://www.thegnomonworkshop.com/dvds/dhi01.html

[RiKToR]

Ive seen it, but havent really worked through it for production yet. Darin does explain how to patch stretching in his for some extremeties on his camera move but but for the most part the camera projection is pretty solid for the move at the most 10 degrees of off axis parallax. I will have to borrow it from my buddy again and try some things.

[Rockhoppermedia]

Sorry I couldnt help cliff, have you thought of doing it as a composite, merging background,mid ground foreground passes. Instead of doing it all at once break it down into its most simple components. you could fake the background parallax by "filming that with a different lens" to to the foreground. I have seen it done somewhere else but am scratching my head who had done it.

would like to help more

Rich

[RiKToR]

I think Ive got it figure out. For the begining of the shot I can deal with a large image and by the end I will probably have to start looking at a number mattes to make the move. THe only other way would be to either project a matte for each building which can work but Im not sure If I want to individualize each object like that with a camera for each. So I will create a matte but make sure that eace building has enough data to overlap, essentially creating an individual projection for each building but keeping to the key moments in the animation.... in this case it allows me to maintain consistancy in grading... and I guess I don't mind the difficulties as long as my shot works in the end.

[RiKToR]

My wife made an excellent point, since she knew that this was going to be an important part to my demo reel. She says, and understand that this brilliance when it comes to CG is rare since she's into the magic of it all and not the tech, "Well if your going to do it different then they (studio) would have you do then it doesn't really make sense. I mean if they would do it with 3d instead and you are just projecting then your not really showing the skills they want since they would want you to do it their way."

So for that, I will put the shot on hold an create it later because I would never be able to finish it by siggraph as far as rendering goes, so as a matte painter I will come up with more mattes to go in my demo reel instead. It makes sense because the studios that have demos of there mattes tend to stick with the whole painted on glass methodology and if thats what there showing then as a matte painter thats what Im showing.

[Rockhoppermedia]

Wow I knew there was a reason why I should get married, seems like your wife is pretty switched on. You do realise in the next couple of days you will be encouraged to buy her some new shoes or that dress she has always wanted. Yep thinking it through if you are going to do mattes do mattes. If they ask do you have any secondary skills, bring up your 3d work. It seems to be that studios have there own 3d workflow anyhow.

I hope your demo reel works, you have been supportive of us noobies and the good karma comes your way

Good luck

Rich:thumbsup:

[RiKToR]

Yeah my wife has had a few nights sleep and I'll watch our 2 month old baby which to her is better then a new dress, besides I usually pick out her clothes for her and I don't have time to go shopping (the few perks of growing up with all girls and very few men) I have a degree in 3d so for me bringing it up is no big deal its in my resume... and I hope what you say about karma is accurate I need to pay these college loans.

[Rockhoppermedia]

A wife and a baby you are indeed a richer man than I and I dont mean material wealth either. I am single at present my job precludes me from ever getting the time to meet any one. Just promise one thing the please dont call the baby matt if it is a boy:rolleyes:


good luck mate

Rich

[RiKToR]

Hehe no, the baby is a girl and her name is Tanya, my son is named Craig... he's five. Though in retrospect Matt was a potential name.

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