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-   Sony HVR-V1 / HDR-FX7 (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/)
-   -   Overexposure (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/236007-overexposure.html)

Sheryl Smith May 24th, 2009 07:41 PM

Overexposure
 
I am consistently overexposing my footage. The latest tragedy is when I shot an instructional DVD under stage lights. I had the subject hold a white board. I used the white balance on the camera to balance to it. And I still have overexposed footage.

In my defense, some of my problem may be that the subject was working with silk which is highly luminescent, especially under light, and had several costume changes. The stressful nature of my work is because there is no margin for error due to the fact that venues and light technicians are hired on a one-time only basis. I'm now wondering if I didn't white balance every single time.

The overexposure is particularly noticeable in the flesh tones and the reds - so much so that the detail is lost on the face or the lines are so severe that the person drastically ages 20 years.

Being a novice at this, there seem to be several features on the camera that somehow have to be balanced to a "sweet spot." I had the shutter speed permanently set at 60 which I'm told is a 'fairly' safe zone.

Any and all help and guidance will be very much appreciated, especially if anyone knows of a tutorial I can watch. I'm looking for a tutorial/ advice that while being stepped out for the novice, is also adequate to deal with this severe overexposure.

I have purchased VEESCOPE which is a software developed by an experienced FCP editor. In fact, it's so now it only works on the Intel chip Apples and that only partially solved the problem. Does anyone out there know about this?

Thank you very much for your help.

Sheryl

Shawn McCalip May 24th, 2009 08:45 PM

All white-balancing does is calibrate how the camera interprets the kind of lighting the subject is being exposed to. If you don't white balance properly, video may appear overly blue or yellow. That's an extremely simplified explanation, and if you don't understand how white-balancing works, it would definitely be in your best interests to learn if you depend on video production for a living.

Shutter speed has an effect on your level of exposure, but its not the main factor. The shutter in a video camera works a little differently than a shutter in a conventional film camera. Basically, the shutter speed for a video camera dictates how much time your imaging sensor has to gather light before the next frame is stored. A shutter speed of 30 or 60 will let in more light, but because the sensor is capturing for a longer period of time during that frame, moving objects will show motion blur. A higher shutter speed of say, 500 or 1000 will appear darker because the imaging sensor isn't exposed to light for as long of a period of time. However, moving objects will remain sharp and crisp- similar to scenes from Saving Private Ryan.

To help with your over-exposure problems, you'll need to adjust your aperture, which is controlled by opening or closing the camera's Iris. You can do this with the small roller control on the V1 located just behind the zoom ring. Depending on how you've set up your camera, you may need to go into the menu and set up the roller to control the Iris.

Once you have control over the Iris, you should enable a feature called a zebra. There is a switch on the LCD side of the camera that gives you that option. The zebra is a great tool that lets you know what areas of the frame are over-exposed. Another good tool to use is the histogram. It can also show you if your frame is under-exposed or over-exposed. There are better explanations of these tools and features in your camera's instructional manual, and this forum is an excellent place to find several more detailed explanations of what those tools do.

I'm not familiar with VEESCOPE, but unfortunately, once you've recorded an image to tape or to a hard drive, its about 80% finished. You can apply tweaks and color correction in post, but what you see is fairly close to what you're going to get. Some software may claim to be able to fix horrible looking footage, but unfortunately, there is no magic bullet that can correct improperly recorded video.

As I said before, if video production is how you make a living, these are very basic and essential things to know about before moving too far down the line. Keep reading through the forums, and especially ready your instruction manual! Hope this helps.

Adam Gold May 24th, 2009 09:36 PM

As Shawn has pointed out, WB really has very little to do with exposure, and you don't really describe your cam, your settings or the shooting conditions enough for us to really help you. But if by "under stage lights" you mean in a theatrical setting in which the faces are lit but the BG is dark or black, just leave your cam in AUTO mode and engage the SPOTLIGHT function, which will prevent the cam from trying to expose for the black areas and consequently blowing out the faces.

You could also set AE SHIFT to -4 or -5, still leaving the cam in AUTO, and that should help as well if you are consistently over-exposing.

You don't say which cam you have, but these functions work the same on both the V1 and FX7.

If you don't know the cam or the basics that well, you're generally best staying in AUTO with these cams and not trying to outsmart them. I've learned this the hard way. And you don't need special software to adjust the image in post, but of course if there's no detail in the blown out highlights to begin with, nothing can bring them back.

Seth Bloombaum May 25th, 2009 12:49 PM

Generally agreeing with the posts above. I do think that 1/60th shutter speed is generally a setting with the most "natural" motion for 60i recordings, unless shooting sports or slowmo.

Your monitor lies. Have a look at http://www.dvinfo.net/conf/824041-post3.html, which will help you set up your monitor correctly.

From there, understanding what zebras are telling you provides the best exposure info.

Sheryl Smith May 26th, 2009 01:23 PM

Thanks for the responses. I'll be trying some trial footage tonight.

Sheryl

Ken Campbell May 30th, 2009 11:24 PM

Hi Sheryl, I suggest you go into the menu system under Display and turn on the Histogram. This is the easiest way to get accurate exposures every time.


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