Getting correct exposure

[Andy Lunn]

I own a xlh1, but I am confused on how to achieve or measure correct exposure, are there any techniques or things I should be looking at?

Would a light meter make the process a lot easier. I often find looking at the view finder its difficult to judge. Any advise appreciated.

[Steven Dempsey]

Yes, you need to engage the zebra stripes (read about those in the manual or on the Web). Depending on your setting, the diagonal stripes will show you what's overexposing. You can close the iris or engage one of the ND filters to reduce the level of overexposure.

Exposing correctly is a real art, it's not just a question of engaging a couple of buttons on the camera. I appreciate the fact that you have a lot of questions but my best advice to you would be to buy a few books on photography techniques and get some basic concepts down.

If you shoot outdoors, you will always be fighting battles like should I expose for the sky or the ground, foreground or background, etc. Indoors is a little easier but can have its own set of challenges.

Knowing the limitations of your camera will help you to make better choices when composing and give you a sense of what is going to look pretty and what's going to look ugly.

[A. J. deLange]

People approach this in different ways and so you must find what works for you. An excellent place to start reading (IMO and perhaps I am showing my age) is Ansell Adams Zone system, as relevent today (again IMO) as when he wrote it up. With digital photography or video the driving principal is that anything that is blown (overexposed) is irrevocably lost but that which is immersed in shadow is sometimes recoverable to some extent by manipulation of gamma in post. Therefore, one apporoach to proper exposure is to increase exposure until a) something just blows and then back off until the blown parts are not blown or b) allow bits of the picture (specular highlights...) to blow keeping the majority of the image is OK or c) (example: the TV series shown in the States called Battlestar Galactica) allow large portions of the picture to blow on purpose. In any event, the zebra stripes can be set to 100% to allow you to effectively procede in this way using any of the three options. Not everyone will agree that this is the best way to do it and I don't assert that it is but you may wish to try it and see if you like the result. Remember that the viewfinder shows a conventional light meter display which will put a 19% gray card (zone V) right in the middle of the luma range (with all the pitfalls of average reflected ligh measurment). A more thorough approach is to use the traditional detailed ligthing ratio measurements of yore.

[Ken Diewert]

Originally Posted by Andy Lunn

I own a xlh1, but I am confused on how to achieve or measure correct exposure, are there any techniques or things I should be looking at?

Would a light meter make the process a lot easier. I often find looking at the view finder its difficult to judge. Any advise appreciated.

I shoot outside alot and I agree with Steven. It's often a matter of blowing out skies to expose foreground subjects. Once you get used to the zebras, it helps. The studiodaily interview that Steven posted somewhere here does mention a good point about exposing HDV... that is, that it doesn't have alot of lattitude. So you do have to be careful.

Also, the stock EVF is way too bright. I have mine on the lowest setting and it's still a little bright. Of course one of those hi-end monitors would help.

But really, think about how much this has changed since shooting film. For one, even the best tape stock is a fraction of the cost of processed film stock, AND for the most part (when you're monitor is reasonably calibrated) What you see is what you get.

[Tom Hardwick]

Andy, lots of good advice in this thread for you. But having found the 'correct exposure' let's talk about locking this down.

When do you need to do this? Almost always, and I'd go so far as to say that with movies it's 'without exception'. If you leave the camera in the auto exposure mode the diaphragm will be constantly hunting, and you can easily see this by turning on the 'display' when you replay a tape. Watch that diaphragm readout bouncing around like an skittzy teenager on alchopops.

Weddings cry out for locked exposure. White girl clutching white flowers in white dress stands alongside her suntanned groom in his black suit. You pan from one to the other and your idiotic (but fast-acting and supposedly accurate) lightmeter goes from f/11 to f/4 (say). Why, when they're both illuminated by the same sun? Your camera will under-expose the girl and over-expose the bloke, so she'll lose her pink cheeks and he'll lose his tan.

Have both in frame. Your XL will decide the correct aperture. Lock this in. Shoot.

When I say locked, I mean locked. This doesn't mean you shouldn't vary this setting - in fact I'll say that video's exposure tolerance means you simply must. Just don't let the diaphragm blades hunt and flick - it looks bl**dy awful.

tom.

[Andy Lunn]

Some very helpful advise thank you. I am using the xlh1 in full manual mode. And as i mentioned I am never sure which f stop to use. If you want good dof, but you have to stop down you lose your dof, is an ND filter the only way to keep that dof while not over exposing?

I will try and track down a book on some of the elements i have asked, i was going to look into a cheap lightmeter. By the way Steven what max setting do you use for your zebra stripes 90?

[Barry Gregg]

Andy;
ND filters in addition to the built-in ones will help with shallow DoF. Another big help on exteriors is graduated ND filters to keep detail in the sky. Also graduated ND with blue or coral can also be very nice.

[Andy Lunn]

Originally Posted by Barry Gregg

Andy;
ND filters in addition to the built-in ones will help with shallow DoF. Another big help on exteriors is graduated ND filters to keep detail in the sky. Also graduated ND with blue or coral can also be very nice.

Thanks Barry. Currently i only have 1 nd filter and the built in ones. Are you saying the nd filters improve the dof? a graduated filter sounds the ticket.

Any ideas where to buy them in the UK? i have a vocas matte box and the filter came with it. What other filters should i have in the old kit bag?

[Barry Gregg]

Originally Posted by Andy Lunn

Thanks Barry. Currently i only have 1 nd filter and the built in ones. Are you saying the nd filters improve the dof? a graduated filter sounds the ticket.

Any ideas where to buy them in the UK? i have a vocas matte box and the filter came with it. What other filters should i have in the old kit bag?

Andy; By 'improve dof' I imagine you mean very shallow dof. Yes, NDs with help reduce the dof by allowing a wide f stop. ND3 is 1 stop light reduction and each number up from 3 reduces the light by one stop. If you are shooting in very bright light you could need quite a lot of ND to get to f 2.0 or so for shallow dof.

Grad filters come in a lot of variations. www.tiffen.com has a number of them. Usually in 4x5.65 or 4x4 glass filters, either soft grad or hard grad. The soft grads for a subtle effect and with wide lens and the hard grad for a long lens or a very quick gradation. The grads can also include both ND as well as color in the same filter.

[Ken Diewert]

Originally Posted by Barry Gregg

Andy; By 'improve dof' I imagine you mean very shallow dof. Yes, NDs with help reduce the dof by allowing a wide f stop. ND3 is 1 stop light reduction and each number up from 3 reduces the light by one stop. If you are shooting in very bright light you could need quite a lot of ND to get to f 2.0 or so for shallow dof.

Andy, if you're outdoors and want shallower DoF, you can also step back a ways, and increase the focal length. At full zoom the stock lens can get pretty shallow in some cases.

[Andy Lunn]

What about exposure at night without being able to use zebras. For true natural lighting. I guess my question goes for outdoor natural and indoor.

Thanks for all the information and advise.

[Ken Diewert]

Originally Posted by Andy Lunn

What about exposure at night without being able to use zebras. For true natural lighting. I guess my question goes for outdoor natural and indoor.

Thanks for all the information and advise.

Andy,

True, natural lighting at night?... If you were to shoot at night using ambient light you wouldn't be shooting in -3db. I've shot some scenes at a turtle nesting beach in Costa Rica in the near dark mostly by dropping the shutter speed. It's OK when there is little to no movement, and is less grainy than cranking up the gain. No matter what though, you will need some kind of light source.

If you give us an example of the look you're trying to achieve it would be easier to comment on. I used to take some lighting courses at film school where we would try to recreate lit scenes from shows and magazine ads. It was both fun and challenging.

[Andy Lunn]

Say.. shooting in the open country side at night, via moon light, to show horizon sillouting but still show some detail in close ups.

[Ken Diewert]

Originally Posted by Andy Lunn

Say.. shooting in the open country side at night, via moon light, to show horizon sillouting but still show some detail in close ups.

I used to work as a PA on TV commercials after film school and budget was not really a factor. I remember one time bringing in about 12kw (or was it 20?)worth of light to replicate sunlight coming thru a window. Despite the fact that it was a sunny day and light was already coming in pretty hot thru the window. But the bank of lights give you a continuous predictable light source.

The problem with your situation is you would presumably need the continuity of a near full moon on a cloudless sky. And then the cam has to be pointed away from the moon, because if you've tried to shoot a full moon, you really have to close down the iris, because it's actually very damn bright. Either that or blow out the moon to shoot your mountain silhouette. I tried that and the result was a shot that almost looked like a sepia version of an afternoon sky. And I'm pretty sure there no way of getting any foreground detail in that same shot without extra light.

I think you're expecting way too much exposure lattitude from this (or any) sub 20k camera. If you review the tests from this camera, it performs it's very best when used in properly lit scenes.

[A. J. deLange]

Originally Posted by Ken Diewert

...if you've tried to shoot a full moon, you really have to close down the iris, because it's actually very damn bright.

As the albedo of the moon is very close to that of a gray card and as the moon is lit by sun which bounces off it and goes through the atmosphere to reach your camera whereas the gray card is lit by sunlight which has been through the atmosphere and then bounced off the gray card the proper exposure for the moon is very close to that of an earth based subject lit by the sun on a clear day.