Jump to content

David Gregg

Basic Member
  • Posts

  • Joined

  • Last visited

Posts posted by David Gregg

  1. I'm looking at it from the perspective of a designer of such systems as opposed to a user - it's not the best tactic to say 'been there, done that' in my case ;)



    Roger that. I find the software to be amazing. Having painfully done more wild tracks without the benefit of such a dead-on lock down, my hats off to the developers! I just wish the sales staffs wouldn't push the "auto tracker" until it learns the difference between good corners, intersecting planes and reflections. All it takes is one bad track point to mess up a perfectly good week.

    my trip to mars

  2. Best case (or worst depending on your perspective, (excuse the pun)) for tracking/parallax is a wide angle lens that is mounted say on an ENG style camera where the centre of gravity is aft of the lens nodal point/points - in fact even a shoulder mount is offset on the LR axis itself ... ;)


    With the offset you can even make a cheat/quasi-3D by using temporal offset as opposed to the traditional spatial offset - also easily achieved with dolly moves where the camera direction is perpendicular to the motion (which many bullet time effects virtually equate to also).


    This stuff fascinates me :)


    If I was putting money or a production schedule on the line, I'd design any post motion tracking show with lots of parallax. Otherwise, things could get complicated and maybe even painful. Been there. Done that.


    Some fun with Match Mover

  3. While I agree pans are an exceptional case in match moving I'd hesitate to say the there is no parallax in a typical pan - more often than not the cameras nodal point (I forget the correct term) is not coincidental with the axis of rotation of the pan head - not unlike our eyes being offset forward from our neck resulting in a small hut appreciable parallax.




    In practical terms, there isn't enough parallax in simple pivotal pan to my experience.


    Most of the 3d tracking software does have the ability to add secondary views from other angles as "helper" files to give it depth data. I only known Maya's (RealViz) Matchmover, but it is happy with most any "helper" file even if it comes from an entirely different camera and lens. Pretty amazing stuff. In any event, I wouldn't recommend counting on a pan for 3d motion tracking. Dolly shots are great though!


    I wouldn't count on the auto-trackers either.



    My link

  4. With the advent of 3d motion tracking a dozen or so years ago, it really became practical to do a lot of shots with realistic animation inserted and interacting with the scene. I have to presume that 3d motion tracking is the primary method (that and a lot of great animation).


    I've worked with Real Viz's Match Move (now Maya's Match Mover). Match Mover and related software products are amazingly accurate for calculating and deriving the camera, its lens and its motion path. If done right, think 1/4 pixel accuracy. The key is that there has to be enough depth information in tracking points for the software to figure out where the camera is. That information usually comes from orbital, trucking or dolly shots since a single stream track has to have enough parallax to figure out the 3d camera and its path. The tracking software is amazing and works even on something like an unregistered film camera. (I was once playing with some old stock film footage on video that had the fields reversed and some screwed up 3-2 pull-down, but the darn thing still tracked it and derived the camera!)


    The high-end systems allow for stills or other secondary shots taken from different angles to be used to provide depth information. Amazingly, most of the software systems can use most any camera's alternate angle to add depth data for tracking. A digital still camera can be mixed with an HD video or film camera for example and it still works.


    About the only thing that won't work is a simple pan from a tripod head or a lens zoom. There is no parallax in a pan or simple zoom so there is no depth data (unless you have "helper" shots of the same scene from other angles).


    My link

  5. It is possible to do it with speed ups in After Effects and generated/animated light streaks. Real Smart motion blur will provide some of the basics for cars getting blurred, but I think not so much the greatly extended light streaks. Particular from Trapcode could post create the streaks. It is used to do a lot of the streaky light effects seen in high-end graphics, commercials and such. Particular demo reel




    Since most of the time-lapse shots are static, it should be possible to essentially "paint" the effect or even lift some of it from stock footage. If it moves on an orbital boom/dolly, it would have to go to 3D motion tracking as a post effect or a serious mechanical setup.


    With trepidation at showing my age, years ago I set up a Bolex 16mm with an Atari 800 computer and a solenoid frame release trigger. That was a fun toy to shoot with at night (extension cords required!).


    It can be done in graphic effects with maybe even a fresh look, but depending on the real requirements, budget, etc., it might be easier to do time-lapse.



  6. Hi

    As a 3D novice, I'd really appreciate some solid advice on creating 'realistic' 3d objects that can be composited with live action.


    My inspiration is 'The 3rd and the Seventh', really a work of art.



    What software should I consider as a starting point?


    Tough question these days since so many software packages are highly developed almost to the point that they are ready for a structural rewrite. Any of the majors are good. I'd just recommend staying with the most common of the majors specializing in whatever area you want to work.


    Photorealism in CGI is still mostly a matter of the animators eye and artistic talent.


    My trip to Mars

  7. You might try Cinefex back editions. Great in depth looks at special effects and how they were done.


    Playing with a few lights, an aquarium and an HD camera can be a fun place to start your own cloud chamber short of heavy particle CGI.



  8. ok, may as well talk about what I've had exposure to...


    How to Train Your Dragon - the Arena Spectacular


    A live show with fire breathing and flying animatronic Dragons that couldn't have happened without the success of a %100 CG film or the hugely successful Walking with Dinosaurs live show which itself wouldn't have happened without the largely CG Walking with Dinosaurs TV series.


    The wire flown dragons are ~1:2 - the walking ones are 1:1 and HUGE


    There are hundreds of films ready to re-staged this way.


    King Kong on stage is in the works


    Imagine: Ghostbusters, Labyrinth - maybe a real 1:1 timing live Muppet Show with a real in theatre residence - give it a decade or two and we might see Transformers and so on.


    And of course it's paving the way for it's own inception of story designed specifically for the format - (and maybe a CG movie spin off rolleyes.gif)


    I guess it's where your interest lie with regards to this - are they working on the films, watching the films, or working with animatronics, scale models and seeing them come to life in any context (it really is interesting how much I personally give away to suspension of disbelief at the distinctly non-animal mechanisms).


    I can understand a love of celluloid - but I'm as happy as a pig in poop working in this field.



    Not big on theme parks as my tastes are jaded about such things and some of the stuff is really old-hat. Besides I'm getting too old to ride roller-coasters all day. I did really enjoy the Spiderman ride at Universal in Orlando. Nice combination of CG stereoscopic scenes tied to riding a motion controlled rig and set work that supported it.


    35 years of stuff

  9. Which makes me wonder if it isn't smarter to reintroduce some of the classic corporate Hollywood model where everything is done in house. That way you always have a trained SFX team, trained stunt team, trained actors, directors, and just crew in general to crank out quality productions.


    In contracting it's all about networking and connections. All but one of the production companies I worked for years back is in business. That's not unusual. Film companies start up and close up shop once the project is done. But keeping the skills and talent alive and within reach when needed, to me at least, seems like a more logical move.



    Oops. The point here being that you wouldn't have these massive budgets making or breaking production companies. At least that's my take. As an example, something we'll never see again are the masses hired for a film like "Spartacus" to represent the hordes of fleeing slaves, or the Roman armies clashing with Spartacus'es army. You simply can't fake the medium long shots where you see actors' and stuntmen's faces, clothes, and just general person.


    I love computers. My middle school in San Mateo County was the first in the world to teach kids how to program. I was part of that. I build computers. I love gaming. But computers are still computers, and there's still an element of controlled unnatural motion that comes with them.


    Again, just my take.



    The key to any efficient production is to pick the right tool for the right job. Some of the worst stuff done is where producers get enamored with a new toy, CGI or otherwise, and its effects and go "ga-ga" over it. Titanic worked in part because the massive amounts of CGI was more like slightly romanticized, photorealist paintings that captured the flavor of the era than literal realism. Practicals, physical models, or CGI, it is still the art that drives the success of the result.


    The CGI in Avatar worked because it was a beautifully painted, realistic-looking fantasy world. I can't imagine that being done any other way, though it was certainly a practical mixed mode production.


    Of course, I'm biased and have been for a generation ;O)



  10. While I've been doing this for a long time, it has been getting increasingly difficult to tell CGI from real no matter how practiced the eye. Of course, there is plenty of low-budget, low-end or unskilled CGI out there too, but there is also a lot of stuff that just gets accepted as real (especially when it is not some kind of wow-me move that gives it away).



  11. Your smoke is too gray (background bleed through) and the velocity feels wrong. If you are doing the smoke in After Effects (or similar) take the smoke you have on black and move the black and white to the alpha channel. You can then put a full field of turbulent whitish gray in the color channels and get rid of the dark ring on the edges completely.


    First thing I would do is find all of the real and movie muzzle flashes I could and compile them into a reference reel to study. Then start building an image based on the real thing, and work toward the imaginary and dramatized version. Finding some real muzzle flashes at night from a similar kind of firearm would be a good thing to find as an element.




  12. It can be done these days and there is even match moving software that will track and create a matching cgi camera. You can even track people and parts of people. However, it isn't easy, simple or cheap no matter what the tool.


    If it is a short film and you don't have a lot of money to spend, I'd suggest thinking primarily practical props with maybe some cuts to close-ups for some CGI production value treats.


    David Gregg

  13. Hi


    We are going to be filming this shot and I wanted to get some ideas from the community for advice on achieving this shot.


    It's going to be a man passing some wheat ears to another person or dropping on table and we want them to turn into a brochure or business cards.


    Any advice on filming and vfx to achieve this? We would like to make it look reasonably good but nothing super fancy.


    Ps: we don't have skills to make 3d renderings so we would like to avoid that. (we do use After Effects)





    I've done a lot of morphs and still take Avid's name in vein after they bought Elastic Reality and essentially dropped the ball. My original Elastic Reality software still runs though even on Windows 7! After Effects is a good adjunct to morphing details, but not a great morphing package.


    Regarding the shot you have in mind, the best morphs are usually done between two similar objects. That's why a face to face morph looks like magic and word morphs often don't. It's really just matching edge distortion and a dissolve, but if you can see the distortion as distortion the magic breaks down and it just looks like a bad morph.


    Going from wheat to a flat square shape (card or brochure) isn't going to work very well unless you can design in some intermediary shape that looks meaningful or perhaps just morph from the wheat to an element of the brochure or card and then sneak or bring the other elements in more conventionally.


    Shot wise after the morph element concept is solved, you have to decide how simply you want to do it. The simplest is a lock-down for the morph part itself. There you only have to make your move (if you have a move) and park on the end to substitute your card or brochure in a close matching position to set up the morph. This part can be done as placing scanned or another realistic image in compositing.


    If you get more complicated as in a commercial of some substance, there are some great 3D match moving software packages out there now (Real Viz -now Maya Match Mover is what I use and used to teach on occasion) if you shoot so they can get enough data to recreate the camera lens and motion path. This of course adds a couple of layers of complication to doing the morph and the shooting some extra production value. In this case with a traveling shot you need to build parallax into the camera motion and or have some other still shots just as 3d space reference taken from other angles (can even be a different camera as the software is very smart). In this case, either the wheat or the end object would be most practically done as CGI. If done right, the match moving stuff in CGI is more accurate than the human eye.



    Again, the locked down shot is about 20 times easier.


    David Gregg

  14. Some things to think about here. Are the older cams really obsolete? I mean they still make the same pictures they did back at the time? Surely if the pictures were good enough then, they are still good enough now?


    Good observation. Technology is one thing and the standards are relatively fixed, but the look and feel of digital images these days is becoming more and more like a good or bad wine vintage. Find a good looking vintage of codec and processing algorithm and it should be great until the wheels fall off (mileage and adjustments may vary)...



  • Create New...