7D Built-In Exposure and Focus Aids for Video? at DVinfo.net

Keith Moreau · November 3rd, 2009, 09:34 PM

Just starting out with the 7D. It's nice to have a superlative SLR, I like the ergonomics and the potential.

I'm having a hard time knowing how my video is being exposed. With my camcorders there are all kinds of ways, zebras, histograms, warnings, peaking. I haven't fully explored the camera, but it seems there aren't a lot of these in video mode.

I thought I'd shortcut my own investigation a bit and ask: Does anybody have hints on how to make sure I'm not blowing out highlights or crushing blacks and if I'm in focus? Don't worry about suggesting the obvious. Maybe we can call this thread "7D Video Exposure and Focus for Dummies"

Thanks all.

Khoi Pham · November 3rd, 2009, 10:46 PM

One thing for sure is don't go by the metering bar, it will help keep you close but it is not 100%, and could be way off if you are shooting a white dress or a scene that has dominant dark or white, I stop using that after too many bad exposure shots, what I found best is that I use the Zacuto viewfinder to focus but also for exposured, make sure that your edit monitor is properly calibrated and hook up your camera hdmi out to it and point your camera to a scene that has highlight and shadow and adjust the lcd brightness with the Zfinder until it is as close as your edit monitor and your eyes as possible, after I've done that, I rely strictly on the Zfinder/lcd, if the scene is not right in the Zfinder then it is not right, comparing the brightness in the zfinder with my eyes and adjust until it is as close as possible, and I say about 90% of my shots are properly exposed, the other 10% I kind a knew that it might not be right but could not adjust during the shoot and just left it there, easily fix in post since it is pretty close already.

Keith Moreau · November 4th, 2009, 03:05 AM

Khoi, thanks for the hints.

What I'm struck with initially is, wow, that's a pretty 'manual' way to achieve correct exposure, relying on the built-in LCD. Also, I'm not actually sure what you mean by the 'metering bar.'

Keep the hints coming!

Jim Jolliffe · November 4th, 2009, 03:59 AM

Call me old fashioned, but try using a incident lightmeter and spot meter?

Khoi Pham · November 4th, 2009, 06:24 AM

Quote:

Originally Posted by Keith Moreau

Khoi, thanks for the hints.

What I'm struck with initially is, wow, that's a pretty 'manual' way to achieve correct exposure, relying on the built-in LCD. Also, I'm not actually sure what you mean by the 'metering bar.'

Keep the hints coming!

It is the bar to the right of the F stop reading on the bottom, + or - 3, or when you pressed your shutter release halfway down it activated it, when the bar is at the center it is properly exposed according the what type of metering you are using, for video there is only 1 and that is evaluative and it is not accurate on certain scene.
Jim, I'm a wedding videographer, don't have time to get a reading from a meter, sometimes you want to catch a hug or a kiss or lightning could change at the ceremony after or before the bride walking down the aisle, we can't run out there and stick a meter on their face, but if you are not shooting event, there is a histogram for playback and so you could shoot a scene and then play back and reshoot if it is not right, but we wedding videographer have to get it right the first time, you can't tell them to repeat the vows for you cuz your exposure is not right. (-:

Jerry Porter · November 4th, 2009, 06:35 AM

As far as exposure goes the metering bar in the live view will get you close then you can adjust with your eyes and a meter if you know how to use one. For focus the best thing to do is take the kit lens off and sell it. Then go buy some lenses that are parfocal (like the new Tamron 17-50 f2.8 and pretty much all Canon L glass) and set the focus just like you would a video camera. Zoom into your subject set your focus zoom out to the frame you want. The lack of ability to back focus was killing me.

Charles Papert · November 4th, 2009, 12:26 PM

There are a few ways to judge focus and exposure accurately before you roll; you can take a still and evaluate the histogram, and you can magnify the focus to make sure your subject is sharp. Obviously if your conditions change once you start rolling, exposure may be compromised and as if often the case with video, the subject may start moving!

A good solution to both is to use a good outboard monitor that has a false color exposure mode, and you will be able to judge focus that much easier. Obviously this represents an additional cash outlay but for me it is the only way to work with these DSLR's.

Using a traditional light meter with a DSLR is in my opinion pretty dicey, particularly when you are working in low light levels. The sensitivity of these cameras is such that a face metered virtually off the bottom of the meter at .7 can look pretty nice even when exposed at 2.8. The only times I use my meters on digital shoots any more is to pre-light a set.

Keith Moreau · November 4th, 2009, 02:50 PM

Quote:

Originally Posted by Jerry Porter

For focus the best thing to do is take the kit lens off and sell it. Then go buy some lenses that are parfocal (like the new Tamron 17-50 f2.8 and pretty much all Canon L glass) and set the focus just like you would a video camera. Zoom into your subject set your focus zoom out to the frame you want. The lack of ability to back focus was killing me.

Jerry, is the Canon 28-135 IS not Parfocal? I kind of like the lens but maybe not suited for manual focus -zoom in focus zoom out to frame video as you say. Have you personally noticed the Tamron is better for this?

Keith Moreau · November 4th, 2009, 02:59 PM

Quote:

Originally Posted by Charles Papert

There are a few ways to judge focus and exposure accurately before you roll; you can take a still and evaluate the histogram, and you can magnify the focus to make sure your subject is sharp.

Charles, one thing I have thought about but not yet experimented with is to establish some type of good exposure using the 7D's live still-mode (non-video) aids, such as histogram, highlight alert (akin to zebras I guess), then flipping the still/video switch over to video. I'm just wondering what results I might achieve, for example, will the equivalent ISO, aperture, and shutter that I've set in still mode apply exactly to video mode?

For example, in still mode, I establish settings to be good (no blown highlights or crushed blacks showing in histogram or zebras) to f2.8 and 1/60th and ISO 100.

I then flip the switch over to video mode, with these settings, will I get predictable results?

Thanks everybody for the great info.

Jerry Porter · November 4th, 2009, 03:19 PM

Quote:

Originally Posted by Keith Moreau

Jerry, is the Canon 28-135 IS not Parfocal? I kind of like the lens but maybe not suited for manual focus -zoom in focus zoom out to frame video as you say. Have you personally noticed the Tamron is better for this?

No it is not. The only Canon lenses that I know of that are Parfocal, are the L series lenses. The Tamron works very well for this at about half the cost of the Canons.

Khoi Pham · November 4th, 2009, 03:22 PM

My 17-55 IS 2.8 is parfocal.
Keith, you can do that but for me just way too long.

Jerry Porter · November 4th, 2009, 03:41 PM

Keith,
I don't know if you know this, forgive me if this seems very basic to you. But, on the kit lens after you focus, if you change your zoom at all the lens is out of focus again. On the lower end lenses I guess Canon figured (and everyone else) that everyone would use auto focus. Eliminating the need for the Parfocal lenses.

Keith Moreau · November 4th, 2009, 04:02 PM

Jerry, no answer is too basic in this thread, as I said, 'for dummies.' I haven't had time to put the Canon kit lens through it's paces regarding 'parfocalness' but I believe you. I just got my new Tamron 2.8 17-50 VR IS lens, are you using that one and how do you like it?

Kin Lau · November 4th, 2009, 04:08 PM

Quote:

Originally Posted by Keith Moreau

For example, in still mode, I establish settings to be good (no blown highlights or crushed blacks showing in histogram or zebras) to f2.8 and 1/60th and ISO 100.

I then flip the switch over to video mode, with these settings, will I get predictable results?

Thanks everybody for the great info.

Just remember that the settings will only hold in M mode and not in any of the other modes.

Brian Ford · November 4th, 2009, 06:39 PM

Quote:

Originally Posted by Jerry Porter

that are parfocal (like the new Tamron 17-50 f2.8 and pretty much all Canon L glass)

Is the non VC version of that Tamron lens parfocal?

November 3rd, 2009, 09:34 PM	#1
Keith Moreau Major Player Join Date: Nov 2006 Location: Brisbane, California Posts: 530	7D Built-In Exposure and Focus Aids for Video? Just starting out with the 7D. It's nice to have a superlative SLR, I like the ergonomics and the potential. I'm having a hard time knowing how my video is being exposed. With my camcorders there are all kinds of ways, zebras, histograms, warnings, peaking. I haven't fully explored the camera, but it seems there aren't a lot of these in video mode. I thought I'd shortcut my own investigation a bit and ask: Does anybody have hints on how to make sure I'm not blowing out highlights or crushing blacks and if I'm in focus? Don't worry about suggesting the obvious. Maybe we can call this thread "7D Video Exposure and Focus for Dummies" Thanks all.

November 3rd, 2009, 10:46 PM	#2
Khoi Pham Major Player Join Date: Nov 2004 Location: Dallas Posts: 747	One thing for sure is don't go by the metering bar, it will help keep you close but it is not 100%, and could be way off if you are shooting a white dress or a scene that has dominant dark or white, I stop using that after too many bad exposure shots, what I found best is that I use the Zacuto viewfinder to focus but also for exposured, make sure that your edit monitor is properly calibrated and hook up your camera hdmi out to it and point your camera to a scene that has highlight and shadow and adjust the lcd brightness with the Zfinder until it is as close as your edit monitor and your eyes as possible, after I've done that, I rely strictly on the Zfinder/lcd, if the scene is not right in the Zfinder then it is not right, comparing the brightness in the zfinder with my eyes and adjust until it is as close as possible, and I say about 90% of my shots are properly exposed, the other 10% I kind a knew that it might not be right but could not adjust during the shoot and just left it there, easily fix in post since it is pretty close already. __________________ Khoi Pham www.proeditproductions.com

November 4th, 2009, 03:59 AM	#4
Jim Jolliffe Regular Crew Join Date: Oct 2009 Location: London, UK Posts: 39	Call me old fashioned, but try using a incident lightmeter and spot meter? __________________ www.jimjolliffe.com

November 4th, 2009, 12:26 PM	#7
Charles Papert Wrangler Join Date: Jan 2002 Location: Los Angeles, CA Posts: 6,810	There are a few ways to judge focus and exposure accurately before you roll; you can take a still and evaluate the histogram, and you can magnify the focus to make sure your subject is sharp. Obviously if your conditions change once you start rolling, exposure may be compromised and as if often the case with video, the subject may start moving! A good solution to both is to use a good outboard monitor that has a false color exposure mode, and you will be able to judge focus that much easier. Obviously this represents an additional cash outlay but for me it is the only way to work with these DSLR's. Using a traditional light meter with a DSLR is in my opinion pretty dicey, particularly when you are working in low light levels. The sensitivity of these cameras is such that a face metered virtually off the bottom of the meter at .7 can look pretty nice even when exposed at 2.8. The only times I use my meters on digital shoots any more is to pre-light a set. __________________ Charles Papert www.charlespapert.com

November 4th, 2009, 03:22 PM	#11
Khoi Pham Major Player Join Date: Nov 2004 Location: Dallas Posts: 747	My 17-55 IS 2.8 is parfocal. Keith, you can do that but for me just way too long. __________________ Khoi Pham www.proeditproductions.com

November 4th, 2009, 03:05 AM	#3
Keith Moreau Major Player Join Date: Nov 2006 Location: Brisbane, California Posts: 530	Khoi, thanks for the hints. What I'm struck with initially is, wow, that's a pretty 'manual' way to achieve correct exposure, relying on the built-in LCD. Also, I'm not actually sure what you mean by the 'metering bar.' Keep the hints coming!

November 4th, 2009, 06:35 AM	#6
Jerry Porter Major Player Join Date: Aug 2005 Location: Satellite Beach, Fl Posts: 784	As far as exposure goes the metering bar in the live view will get you close then you can adjust with your eyes and a meter if you know how to use one. For focus the best thing to do is take the kit lens off and sell it. Then go buy some lenses that are parfocal (like the new Tamron 17-50 f2.8 and pretty much all Canon L glass) and set the focus just like you would a video camera. Zoom into your subject set your focus zoom out to the frame you want. The lack of ability to back focus was killing me.

November 4th, 2009, 03:41 PM	#12
Jerry Porter Major Player Join Date: Aug 2005 Location: Satellite Beach, Fl Posts: 784	Keith, I don't know if you know this, forgive me if this seems very basic to you. But, on the kit lens after you focus, if you change your zoom at all the lens is out of focus again. On the lower end lenses I guess Canon figured (and everyone else) that everyone would use auto focus. Eliminating the need for the Parfocal lenses.

November 4th, 2009, 04:02 PM	#13
Keith Moreau Major Player Join Date: Nov 2006 Location: Brisbane, California Posts: 530	Jerry, no answer is too basic in this thread, as I said, 'for dummies.' I haven't had time to put the Canon kit lens through it's paces regarding 'parfocalness' but I believe you. I just got my new Tamron 2.8 17-50 VR IS lens, are you using that one and how do you like it?