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-   Sony TRV950 / PDX10 Companion (https://www.dvinfo.net/forum/sony-trv950-pdx10-companion/)
-   -   burn-out background, please (https://www.dvinfo.net/forum/sony-trv950-pdx10-companion/23509-burn-out-background-please.html)

Jim Schweer March 25th, 2004 10:34 AM

burn-out background, please
 
I'm shooting a scene against a white wall with my TRV950. The main source of light is a large window in an adjacent wall with northern exposure (i.e., no direct sunlight). I would like the background wall to burn out in the finished image (think of the scenes with the real Harvey Pekar in American Splendor). If this is possible, would it best be done by adjusting the exposure during the actual shooting, or by some manipulation in post (FCP4)?

Thanks.

Shawn Mielke March 25th, 2004 06:40 PM

In my small amount of experience with FCE, I recommend doing it in-cam. Yes, yes, I know, by doing it in post, you get to have the choice right until the last moment of post production...except that it just doesn't look as good. I have done some in-cam burning of back walls, and of close ups of people, with marvelous results. Software effects just aren't the same. Be sure it's the right thing to do, take a risk, and commit to it.

Sean McHenry March 25th, 2004 09:15 PM

Burn in
 
As an editor and other things, do it both ways. Frankly, I don't know how smooth you can do it with the small exposere buttons and wheels very smoothly. Avid has a function called dip to color and Premiere has a similar thing. This combined with a nice soft gausian blur in both directions should give a really slick and smooth (ie., key-framable) effect.

Who remembers the old Robert Palmer videos? Like doing the "high key" thing over time and taken all the way as a transition. I think "6 Feet Under" uses this once in a while too. Seems to be (thankfully) taking the place of the old fashioned ripple effect for flashback sequences.

Sean

Wayne Orr March 26th, 2004 11:03 AM

In order to "blow out" the white wall, you want to overexpose it by about two stops. Your problem, Jim, will be to overexpose the wall without overexposing your scene. If you will be shooting only a talking head, you may be able to flag the light off your subject enough to give you proper exposure on the subject while leaving the wall overexposed. Any scene bigger than a talking head will be very difficult to flag, while leaving enough sunlight on the background wall.

Wayne Orr, SOC

Jim Schweer March 29th, 2004 09:35 AM

Thank you for the responses I received. And yes, Wayne, the picture is "blown-out," while I am "burned-out." All the answers were useful to me.

Jim S.

Mike Sanchez March 31st, 2004 03:41 AM

Hi,

I agree with Shawn M. regarding doing it in cam (largely because my editing platform is so slow I do everything possible in cam and then just DVD editing and chapter setup in post to minimize render time).

On the TRV950 we are blessed with SPOT exposure while the LCD is open. Combine this with the ability to slightly offset exposure + or - a bit in the CUSTOM PRESETS and exposure in your situationis is both easy and accurate in cam.

Open the LCD. Select FN and go to the page where SPOT Exposure is available. When the little white box opens up....locate the face or object you would like properly exposed (and at this point I would NOT be using any of the built in exposure modes....just the auto mode). Touch the location on the screen and that object will be properly exposed.

If the object is a Caucasian face carefully examine with zebras to make sure your zebra at 100 is not lit anywhere on the face. If it is......go to Custom Presets and reduce the auto exposure a little bit until the zebra on the face vanishes. This will give a perfectly exposed face in any background.

I do this all the time in my house because almost every scene is backlit by a window with (in winter) snow outside. Very difficult lighting made easy by the SPOT metering.

Ignacio Rodriguez March 31st, 2004 11:45 AM

> On the TRV950 we are blessed with
> SPOT exposure while the LCD is open.

Mike, would you not get some smearing when overexposibg the backgound with the 950? I also think it's faster to do it in the cam but in the case of the 950 (and the PDX10) I would try to be very carefull, these cam's CCD sensors are not suited for very high contast.

Shawn Mielke March 31st, 2004 12:03 PM

It would take an enormous amount of light to get a wall to smear, I'd think.

Walls are so often more reflective than human subjects anyway, it will proabably be no trick to up the exposure and get your effect without losing ths subject in the process.

Mike Sanchez April 3rd, 2004 03:53 AM

Ignacio,

For smear I have two answers:

1. The first TRV-950 I bought back in December generated smear and glow around just about every white object. That coupled with feedback squeal in the audio for higher notes led me to send it back to Sony.

2. The second TRV-950 I have now has very, very little smear. In fact, the same window that would smear the entire image previously, now does not smear at all. I can get a little smear if the window has vertical panes, the sun is out, the internal room is dark and I move the camera around until I just see a bit. Also, at very high shutter speeds vertical white objects will slightly smear.

But......my second go a the TRV-950 is a much better CCD assembly apparently.

Not that the second one is perfect. It has hum in the audio when the LCD display is set to NORMAL brightness. But....when set to bright it is super quiet audio so I've decided to keep the thing and burn the LCD out on bright. IF and when I do this again I will take my headphones to a reputable Sony authorized dealer along with some test lights and take the product out of the box and test them until I find one that came off the line in good shape.

Ignacio Rodriguez April 3rd, 2004 10:42 AM

Ok Mike, it sound's like your first '950 might have had an optical problem. Smear is an electronic problem originated by the CCD's physical nature and is only vertical, so you cannot smear an 'entire' image unless the high luma zone of the image spans the whole width of the frame.

Jim Schweer April 20th, 2004 01:33 PM

For anyone who's interested, here's how got the result I desired: a performer standing in front of a blown-out background. I did do it in-camera, but I gave up on using the sun for illumination due to its inconsistency and the difficulty I had matching the exposure shot-by-shot through the morning. Instead I shot in the middle of the night. But I didn't need much in the way of lights. The total wattage of my "light kit" was 260 watts.

The performer, who didn't need to move much, stood five feet in front of a white wall and was framed from the knees up. I positioned a 100 watt clamp light just outside either side of the frame and shining on the wall, then adjusted the exposure on the 950 all the way up and watched the zebra stripes cover the LCD display behind the performer. I lit the performer with a 60 watt clamp light shining through a hanky and used foamcore for the fill. And it worked.

Jim S.


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