Using AE shift with the FX1000

[Jeff Harper]

Ok, I've just seen three references in one day using a negative AE shift setting to improve picture quality. Most recenly was Ron E. If finally dawned on me I should learn about this.

What is the idea behind using AE shift settings, and why use the minus setting in particular? I've just changed the setting on my camera to -3.

Are there times I would turn off the AE shift, or are there times when it is best to use it?

I'm excited about this feature and absolutely cannot believe it has been on my camera and I haven't played with it to see how it can help my PQ.

There were two very important urban shots of my bride in a downtown alley yesterday that were overexposed because she was against a black garage door (that was a new situation for me) and I suspect that if the AE shift has been set to -3 or -6 it would have been much better, as it happened so quickly I didn't have time to go manual and adjust before the shot would have been missed.

[Adam Gold]

Unlike many people, I like Auto Exposure and use it all the time, especially in conjunction with SPOTLIGHT when shooting stage shows. But sometimes, even outdoors, my zebras are reading that I have way too much stuff in the hot, blown-out zone. So especially in days of bright sunlight (we don't get too many of those around here), I'll set AE shift to -5. It helps keep the brights under control.

But frankly, a better tool for this is KNEE POINT on the FX1000. On my FX1s and FX7s, though, I use AE SHIFT as there is no KNEE POINT control.

I have SPOTLIGHT on a hot button on all my cams and use it to toggle quickly whenever I have someone against a dark BG. It's virtually instantaneous and foolproof, and even if it doesn't get you 100% of the way to where you want to be, it reduces blown-out highlights enough so you can easily tweak the rest of the way in post.

[Ben Hall]

Can you go into more detail on the AE shift, spotlight and knee point settings - what they do, why and when to use them?

Would be helpful for a newb like myself who is still learning what this beasty can do...

Cheers

[Adam Gold]

They're all explained pretty well in the manual. AE SHIFT tells the cam to go lighter or darker by an amount you tell it to than it normally would in Auto Exposure mode. SPOTLIGHT is for contrasty lighting conditions, where normally the cam would try to expose for large dark areas (as in a theatre) and consequently blow out the highlights on the faces, so it makes the camera go darker by a couple of stops to avoid this. KNEE POINT is similar -- it tells the cam to bring down really bright areas at a certain point (you decide where) to a more manageable level.

So when we do stage shows, where there always many large areas of darkness that are supposed to remain dark, and small bright areas like people's faces, we use SPOTLIGHT, AE SHIFT at -5 and, sometimes, KNEE POINT set to AUTO. Basically we're doing everything we can to retain details in the brightest spots while allowing the darkest areas to go full black. But you could also use these settings in bright sun to control your highlights.

Note that the KNEE POINT setting is buried in the PICTURE PROFILE menus, so you can set it to have different values in up to six different customized groups of settings. I have one PP for Sports and another for Theatre.

[Ben Hall]

Excellent, thanks for that - I can see how those features can be really useful. I had read about the AE feature in the manual, but hadn't twigged on it's usefulness. In fact, this is the main reason I often go into manual iris - when the camera is underexposing backlight subjects. AE will be excellent for this. Thanks for the tip.

The thing about things like knee point is that this is my first decent spec camera, and because there are twenty or fifty parameters to adjust picture settings, colour, brightness and other more techy stuff - it's difficult to play with this for fear of doing something bad and letting the footage suffer as a result - so it's handy to know what settings other people have arrived at and why as a starting point for experimentation in arriving at the settings that will work best for me.

Appreciated - thanks.

[Ron Evans]

I use my XR500 as an unattended full stage camera for stage shows, set with spot focus. I also use a SR11 also with spot focus. With the SR11 I prefer to set the exposure manually as increasing the gain when stage goes to black introduces very obvious grain at wide open and 18db of gain which is where they will go in full automatic regardless of AEshift. The XR500 has such low noise that I can leave it in auto AE shift -4( unfortunately the most it will shift) and even at 18db gain it has less grain than the FX1 at 12db. It still overexposed a few times on white shirts that where in a hot spot on stage but most of the time it was excellent. I have used it now in the last three shows with excellent results and find it gives a better result than "spotlight" for me as this camera sees the whole stage. A single person highlighted would be better with "spotlight". Having now seen the difference between the FX1 and the SR11 and XR500 the FX1 is going up for sale and a FX1000 will replace it soon. For stage show I will like the black stretch( to bring out shadow detail) and knee ( to cut off highlights) that the Z1 had but Sony left off the FX1. Luckily they are on the FX1000.

Ron Evans

[Adam Gold]

Ron brings up another great point -- gain and noise. To avoid the cams gaining up ridiculously when the stage goes black, I set a max of 12dB on the FX1s and 7s, and 9 dB on the 1000 (the older cams only give you a choice of 6 or 12, no 9. If they were as good in low light as the 1000, I'd set the max at six.) This is either in the CAMERA SET or PICTURE PROFILE menus, depending on the cam. I'm considering playing around with just setting them all at six anyway.

But I tend to crush or compress the blacks rather than stretch them -- I want everything below a certain point to go full black, and I find that when stretching, the blacks go dark grainy noisy gray -- they "sparkle." But that's just a personal choice.

[Robert Petersen]

I have produced many indoor "live production" video's and I always set the exposure to the minus side. I have not used my Z5U yet, but have done it with a PDX10 and an HV30. This is a must with stage and spot lighting to prevent bright areas from being blown out in the video. I then correct for any underexposure in my editing software, which allows me to bring the video to a normal level while totally controlling any potential overexposure. The results have been very good. The zebra function is very useful in setting the amount of negative exposure.

[Ron Evans]

Originally Posted by Adam Gold

But I tend to crush or compress the blacks rather than stretch them -- I want everything below a certain point to go full black, and I find that when stretching, the blacks go dark grainy noisy gray -- they "sparkle." But that's just a personal choice.

I have enough of a problem discerning detail on stage with a dance performance of dancers in black costumes on a black stage without making it worse with black compress. There is a danger of the outcome being faces and hands moving about a black stage!!! It is however one of taste. I like detail and detail in the blacks gives depth to the image, but also the lighting effects so only the XR500 is in auto the SR11 and FX1 are in full manual so have the full effects of lighting hopefully as seen by the audience rather than being normalized by an auto exposure. Having the XR500 in auto has allowed me to use this shot to cover the time it takes at the performance to manually get exposure in range on the FX1 for really big lighting swings I can always make the XR500 a little darker in post to match what really happened. The XR500 really fits the requirement I had for a camera that I can leave in auto mode and cover for the times I will be changing something on the main camera.

Ron Evans