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Canon XA and VIXIA Series AVCHD Camcorders
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Old March 25th, 2012, 06:35 PM   #1
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XA10: correct exposure with 18% gray card?

I watched this person's video tutorial: Getting Perfect Exposure - YouTube
And am trying to apply the same procedure with the XA10 but in auto mode, I can't figure out how to make it display the aperture and shutter speed.. Also, this camera has a gain feature, not sure what that should be set to as well...

So I have my 18% grey card. Can someone help me with the proper procedure to get the correct exposure?

Thanks so much!
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Old March 25th, 2012, 07:16 PM   #2
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Re: XA10: correct exposure with 18% gray card?

The 18% gray card is legacy from still film photography and is intended for the light response of film. They are important for film because you do not know if you got the exposure or white balance right until after you "soup" the film (long live bracketing shots). Video gives instant feedback on your monitor, and it also has zebra to assist managing you highlights, and in general they can give better results than blindly relying on an 18% gray card, especially in unusual lighting conditions or if seeking specific artistic exposure effects.

That said, in manual exposure mode the exposure can be displayed. From function select Rec. Program Mode and then Manual. The DISP button toggles the on-screen display (including the aperture, shutter and gain) on/off. Select the one you wish to adjust and have at it.

The U-Tube you linked interesting, but perhaps a bit simplified. The purpose of gain is to amplify the signal from the CCD/CMOS. It does not distinguish between desired signal and noise nor does it "add noise." It just amplifies what is read from the CCD/CMOS, be it desire video image or noise, equally.. Thus it will make any existing noise more apparent along with any existing desired image signal.

In auto mode you are trusting the camcorder to make the exposure. If using the gray card you will need to lock the exposure while on the card.
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Old March 27th, 2012, 10:25 PM   #3
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Re: XA10: correct exposure with 18% gray card?

Well, I went to auto mode and took a snapshot of the gray card. Then I put it in the computer and looked at the EXIF data, which showed:
f 2.8
1/60
and the gain was on 12dB

So I shot a few seconds of film and dropped it into the computer. Got to say that it looked rather dull and uninteresting, then I saw another post on a diff forum that says to always have BLC (backlighting feature) set to on and up the brightness and contrast settings too.. so I will shoot a bit more and see what it looks like.

Then the other problem is that what I'm seeing on my computer monitor will look different on someone else's because everyone has different settings.....

Edit: Well I went ahead and did another test, this time in AUTO mode, where I have no control at all over the exposure or anything else. Have to say that it looked much better than anything I achieved with Manual mode. So maybe I shouldn't mess with manual mode at all since it's not as good as Auto? I even tried upping the contrast and brightness and color depth in manual mode and it still looked lousy compared to Auto...

Last edited by Mike Costantini; March 27th, 2012 at 11:02 PM.
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Old March 28th, 2012, 06:52 AM   #4
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Re: XA10: correct exposure with 18% gray card?

[quote[then I saw another post on a diff forum that says to always have BLC (backlighting feature) set to on and up the brightness and contrast settings too.. [/quote]

What works for one person's taste may not for another. Depends on your artistic objective and what the client wants/expects.

Manual exposure will generally give the best results once you learn how to do it and if you have the time to manage the settings during your shoot. Using auto mode can work OK for "average" conditions, average meaning the condition around which the exposure program was dsigned.

Think of manual vs. auto mode as being a bit like playing the piano. Auto mode being like using a piano roll - you get what you get per the piano roll creator (usually OK but not great). Manual being like playing the piano with fingers on the keys - it takes practice to be any good at it.
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Old March 28th, 2012, 09:48 AM   #5
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Re: XA10: correct exposure with 18% gray card?

Mike,

Don’s analogy of a piano is only fair if you are talking about a camera that has the same number of keys available. The problem is it’s missing the little black ones and/or they are so hidden, playing the piano can be darn near impossible.

What you are discovering is with some cameras what happens in auto cannot be easily replicated and if you cannot determine what the camera is EXACTLY doing for a certain scene, it’s an effort in futility. Add to that the adjustments you have to make are buried in a touch screen menu, 95% of the time you won’t be able to dial up a better picture regardless of how much time you spend and 100% of the time you will miss something trying.

My G10 (XA10 with no handle) stays in auto with a button assigned to the backlight feature. My XF100 runs on auto 90% of the time on a Fig Rig with the face detection on, it’s used mostly for close quarters and moving people. With it’s “one ring, three functions” set-up its auto function with face detect can easily can out-perform me trying to manipulate that set-up, and everybody else on here also. Not until the XF300 comes out can I really start playing the “piano”.

I know I’m the only person on here who hasn’t super-glued their cameras to manual mode. But as manufacturers take more things away, combine functions to controls that need to be operated independently and bury them deeper in touch screen menus, many cameras require surrendering certain parameters to auto. And with all the fast moving, shallow depth of field and out of focus footage so popular today, I pray others will start to realize this also. Good luck with your camera!
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Old March 28th, 2012, 11:18 AM   #6
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Re: XA10: correct exposure with 18% gray card?

Well my shooting needs are pretty basic, small 10x10 room, plenty of soft light, shooting some music instructional material.. Just need a nice bright crisp scene really. I may just go with auto mode since it seems to be looking best.
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Old March 29th, 2012, 07:28 AM   #7
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Re: XA10: correct exposure with 18% gray card?

Quote:
The problem is itís missing the little black ones and/or they are so hidden, playing the piano can be darn near impossible.
It goes back to learning where the keys are so it is second nature to you, and having the time (extra time in the case of fewer physical dials/buttons/controls) to employ them. Not easy in run-and-gun mode or if you spend only an hour or two a week using the camcorder. The XA10/G10 are great camcorders at their price points, but they are essentially entry level pro/prosumer, and are marketed to people who will likely make more extensive use of the auto exposure modes than someone buying, say, the XF305.

The point being that the manual modes become important as you encounter difficult lighting situations or are seeking specific exposure effects.
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