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class="style1">Shooting 3D in SD and HD - NOT IMAX

>Published : 13th March 2007

>Dear Members,

>I have been enjoying this list for a long time, especially its wide range of discussion and help.

>Now there is a topic which I was missing and didn’t find clearly mentioned or truly separated discussed in the archives: Shooting in 3d.

>I hope you don’t mind my silly questions and could help me in getting more information on this subject (books, links, thoughts, etc.).

>I might get the chance to shoot a 3D short some time next year and wanted to inform myself at first on this list, as many of you have extensive experience and are very keen on any known linkage to the process of filming and post production.

>The project I mentioned will be shown in a 3D-Cinema, running fully digital from two computers that feed each one HD-Projector (DLP/JVC); projection resolution will be 1280x788 (as I recall), screen size is app. 4m x 2,8 m. Camera system is not specified yet (but it will be two cameras grouped together for the 3D-effect), and there is no gear yet available for zooming in or follow focus action (unfortunately) at my place. It is going to be a big challenge for me, as this type of screening is special

>(3D+sensory seats+smell/perfume) and pretty new to my country.

>1/.   What are the known problems/errors in the process of shooting 3D in SD and HD, regarding zooms and follow focus/movement of the camera (and actors) towards or away from the camera?

>2/.  Is there a safe way or procedure to align the two cameras, so that the two frames will match for the chosen focal length?

>3/.  Do I need to have one of the two lenses at a wider focal length? I heard that this would aid in the 3D effect.

>4/. Does resolution of the final projected image (remember: 2 projectors) suffer in terms of quality, as you will have a full resolution picture for every eye (polarized eyeglasses)?

>5/. Do you know someone that is currently developing camera gear for shooting in 3D or already has perfect solution?

>6/.  How will be post production affected (complexity)?

>7/. Does filtering in front of the lens - aside from using one polarizer on one camera (which will be needed, as I heard) - interfere with the quality of the 3D-effect?

>8/. Are there any lighting problems, that might occur on set when using this two- camera-system?

>I know that there are many more questions, that I didn’t ask or probably even thought of (complexity?), but I am sure that in the process of discussion there will come up much more interesting points that hopefully lighten my up.

>I hope I didn’t bother you too much with my concern and look forward on any information or advice.

>With best regards from Austria,

>Wolfgang Bnkowski


>Hi,

class="style2">>> 7/. Does filtering in front of the lens - aside from using one polarizer >>on one camera (which will be needed, as I heard) - interfere with the >>quality of the 3D-effect?

>Are you sure they didn't mean one polariser on each projector? That's usually how dual-projector 3D works.

>Phil Rhodes
Video camera/edit
London


>Hello Wolfgang.

>I don't have a very vast experience in this area, but I can help you with some stuff.

>First, you do no need a polarizer in the camera. In fact, it can give you trouble in there. The polarizer is used in the theatre to filter the light coming off the projector, so each projector will have it's light polarized in one direction. This, in conjunction with the filters in the glasses make each eye of the person to see only one image. If you filter the light with a pola on camera, you don't get this effect, since the projector will be a whole new light source. In fact, if you want to use the pola in camera, for sky or reflections, you have to be careful to align both, so the effect will be exactly the same on both cameras.

>Speaking of zooming, you have to be careful, because for each focal length you have a minimum distance that you must keep of the subject. Monitor both cameras, and if possible with an multiplexer, to see a preview of the 3d effect on set. Objects or shadows that only appear on one camera will be disturbing. If you edit the video on a simple system, edit one side, then rename the files to apply the same edit on the other side (keep your files with the same duration, and sync them properly). Or edit both together, cutting both, you can have more errors and problems in the editing process, but you can also view other cameras at the same timeline... so, your choice. You can also correct a little of the parallax on post production, but be aware of the resolution losses, as you make the images closer (put the left image a little more to the left, for example, so the objects are closer on the screen, give you a much taller image, so you may crop to keep the aspect ratio).

>Oh, yes, parallax. Keep your cameras the closest possible and always aligned, pointing to the horizon. Unless you want to try same thing that can cause headaches.

>You can also use a split adapter on the camera. this is a optical adapter that will give you two images on the same camera (obvious, with half the camera resolution).

>Recommend HD cameras if you choose this, and be careful with the weight of the adapter.

>Sorry for the terrible English...

>Daniel "chewie" Sanchis
Brazil


>For 3D HD Vince Pace is the man to talk to his rigs are amazing.

>Remote controlled adjustable inter-ocular and convergence with compensation for the differences between 2 different zoom lenses programmed in.

>Of course they've also got all the usual remote zoom, focus & iris as well.

>Based on 2 * Sony F950's in their T mode.

>Just quality engineering and design at it's best.

>Cheers

>Geoff Boyle FBKS
Director of Photography
EU Based
www.cinematography.net


>Thanks to all of you for the information I got so far - also off-list.

>To Geoff :

>Do you have any links regarding Vince Pace or his rigs?
Id like to ask him a question or two.

>Greetings,

>Wolfgang Bankowski


>Wolfgang,

Apologies for not commenting sooner. I tend to hover on the 2K list and catch up quarterly on all my other cml forums.

1/.  What are the known problems/errors in the process of shooting 3D in SD and HD, regarding zooms and follow focus/movement of the camera (and actors) towards or away from the camera?

I would more refer to it as challenges then problems. The challenge is to calibrate, synchronize, and register two individual camera systems so they work together as one. Fortunately for us, eyesight does that whole process with very little effort.

Aligning cameras and lenses must be done with both mechanical adjustments and software adjustments.

2/.  Is there a safe way or procedure to align the two cameras, so that the two frames will match for the chosen focal length?

With primes it is easier. There is a simple match of the two frames for a given focal length. Zooms can be much more challenging and must start out with minimal offset during its track from the wide to tele. Make sure you have an overlay of the image to compare the offset.

>3/. Do I need to have one of the two lenses at a wider focal length? I heard that this would aid in the 3D effect.

I have experimented with this offset but it leans more to the gimmick of 3D rather then the emulation of eyesight, so I don't spend much time dwelling on the effect.

>Our approach is to shoot as corrected as we can and then use post to create any enhanced gimmick a particular client might be going for.

>4/. Does resolution of the final projected image (remember: 2 projectors) suffer in terms of quality, as you will have a full resolution picture for every eye (polarized eyeglasses)?

I think it gains rather then suffers. Many times one eye could have flaws that make it unacceptable for viewing in 2D, but when projected in 3D, the flaws have less of an impact on the overall image, making it acceptable. However, I would not want to bank a whole show on flawed footage. I am just indicating on some shots, you will find having two steams of footage softens the flaw.

>5/. Do you know someone that is currently developing camera gear for shooting in 3D or already has perfect solution?

I wouldn't call our solution perfect, but it is a very strong system for on set production. We have varying levels of development in house from Corvettes to Ferrari's. You mentioned your project will be in 1280 x 768 resolution. We have a system using the Panasonic Varicam box cameras available.

>6/. How will be post production affected (complexity)?

If you create a strong 3D product during acquisition, it will allow you to concentrate on the 2D stream in post with better results. 3d that is not strong during acquisition makes the post equation much more complex and time consuming.

>7/. Does filtering in front of the lens - aside from using one polarizer on one camera (which will be needed, as I heard) - interfere with the quality of the 3D-effect?

I might not understand this question completely. The projection system requires the output to be channelled using polarisers for each projector. The camera system can take advantage of polarisers if they cover each lens in a similar rotation or one larger polarisers covers both lenses.

>8/. Are there any lighting problems, that might occur on set when using this two-camera-system?

Consideration should always be given to highlights that might ghost a diverged image in your field of view. The key here for all of your questions is the HD format allows us a real time viewing platform to make educated decisions regarding 3D.

>The mathematics is not the driving force and makes way for the creative interpretation to take over. When I work on set in 3D, the gaffer, grip, and Director are all making their decisions based on a real time viewing image. Once they understand the result of their actions it is simple for them to make the slight offsets to create a more entertaining 3D effect.

Wolfgang, there are other companies in this group like Cobalt and ParadiseFX to service your needs. I suggest you tap in to the talents of my company or Cobalts / ParadiseFX for a successful 3D shoot. Good 3D, both on set and delivered to the viewing public is a plus for any of us involved in the development and content markets. So it benefits all of us to work together.

class="style2">>>I think it gains rather then suffers. Many times one eye could have >>flaws that make it unacceptable for viewing in 2D, but when projected >>in 3D, the flaws have less of an impact on the overall image, making it >>acceptable.

>Clarification of the above : This statement was made in reference to resolution and twin projections. Flaws were meant to describe noise or softness in the image that may be helped by the fact there are two independent footage streams in the final product. It was not meant to refer to lack of calibration or synchronicity with the two streams to each other.

Good Luck,

Vince Pace
DP LA