"Correct" Exposure with the GL2

[George Brackett III]

Will- I don't get it. If you were using manual exposure (and zebra stripes), why was it so underexposed? I shoot indoors all the time, with no problems

[David Ho]

"I could not believe my eyes, and it has permanently changed my outlook. The GL2 footage was dark, dark, dark. Faces in a group could not be distinguished. By contrast, the TRV8's footage was just fine."

Will...are you talking about shooting indoors using the GL2? Or shooting after you left the GL2 idle for a long period of time? Whats the problem?

[Will Fastie]

This was just shooting indoors, not an acclimation problem.

Sounds like I have something to learn here though. What should I be doing when I'm shooting indoors in lower light?

Will

[Lyndon Golanowski]

I shoot indoors lowlight often, if I use it manually I can get an ok look, however any lowlight and this baby gets grainy fast, I can use it in lowlight and faces are clear etc. but the grain sucks, if I were you I would buy the vx2100 if you will be using it for low light, its minimum lux is 1, and I think the GL2 is 6. I am not sure of GL2 for sure, but it's probably around there...But if you dont mind grain in your footage then GL2 is wicked, In good light it puts the vx2000 to shame(not sure of 2100)...my 2.


Shooting indoors with GL2 takes a while to get down, but its pretty easy, switch to to Manual, and play around with your shutter, 1/60 is the minimu, once your at 1/30 you get a slaggy look with some tracers, so 1/60 and up is good, from there on out its just playing with the other settings until you get good footage, watch your db settings 0,6,12 to make sure you dont get to much grain..its all about experimenting..

[Alan McCormick]

StMichael,

Have you checked footage on a PC or your TV for the grainy look?

The manual exposures will give you that fine tuning and I have found the auto is not the same (I have XM2 and am going to vid forum at Wembley too on Tue 10th Feb).

[Michael Connor]

No Alan i havent, just on my computer, which isn't ideal i guess? I did burn a dvd from some footage, but i assumed the poor quality was the codec in the software, i dont have a proper card, just an on board firewire port at moment. This is something im beginning to fear. That the image i see in my view finder, and on the small screen, is different to that which is on my computer, and again to that which was on my TV! I know i did have some footage that looked great on my camcorder, but a lot darker on the computer. Its all practice i guess. Yea would be good to meet up with anyone from forum at wembley forum. Im not sure what days im there on either, considering a couple.

[Alan McCormick]

I had a major problem (darker image on PC monitor compared to Cam viewfinder) till I used a TV monitor and found it was a lot brighter.

Initially in post editing (using Liquid Edition) I used to increase the brightness etc to compensate but then when viewed on the TV it was over exposed. Speaking to a few friends I decided to check out the PC monitor to find the settings had been changed :( once corrected that all is now OK.

Sorry it is not a technical response but that is just me.

[Michael Connor]

yea, someone else where on the site wrote an interesting bit on 'exposing' to the right i think it said, being a little over exposed. But ive spent so much time reading, and like i said whenever i find a good setting, and flick back to auto, then back to manual, i find the pic doesnt change, which means the auto already got there. I know this is true because if you pic a really dodgy setting in manual, then flick to auto, and back to manual again, you see that the manual stays as it is. Mind you, im limited in experience and talking about indoors. I have not done a lot of sunlight filming, and saw a huge new spectrum of technicalities when i tried to film a sunset from my back garden the other day. A lot of what people say seems to be more true here, and it looked good in auto, but also good with various different appeture & frame rate settings, and also the gain mada a difference in grain. By the time id made my mind up what looked best the sun had dissapeared into the horizon!
With monitors i have a small programme that came with my graphics card that helps me set colours. But to be honest ive dissabled it as it keeps trying to connect to the net (my editing computer is not connected) so i may have a problem there. And my TV is so old the colours are dodgy anyway!
As for post editing... liquid edition, whats this? I havent bought any expensive software yet, am building up an archive of footage, and considering taking the plunge and getting a card by cannopus, as im led to believe form a good friend that a lot of the other non linear sortware and cards available have quality issues with the mpeg2 codecs.

[Alan McCormick]

The thing to watch with auto exposure is if the light changes suddenly the Cam "may" not catch up as quick (one good reason for manual).

Maybe one of the experts can expand on this more.

Liquid Edition is one of the editing suites out there, I love it but as any suite you will gel to one you like. The best bet is to try a downloadable trial (go to web sites) before you buy as you may not like all of them. The other thing is to ensure your PC is good enough for editing.

[Ken Tanaka]

I have split these posts off of their original thread, whose primary tpic was where to buy a GL2 in the dayton, Ohio area.

[Ken Tanaka]

In discussing the matter of obtaining correct exposure with the GL2, or any video camera, it is important to be mindful that the primary target viewing venue for all video cameras is a television. Computer monitors, whether lcd or crt, when acccurately calibrated may offer reasonable facsimiles of the camera's imaging product. But they all operate with different display technologies and have different color characteristics than a television. This is also true of the lcd displays (flip-out panel and viewfinder) on the camera itself. They present facsimiles of the camera's imaging. Nothing more.

The only way to accurately and neutrally judge the camera's color and exposure is to use a calibrated production monitor. Ditto for post-production color correction, adding supplemental displays here such as RGB parades, waveform monitors and vectorscopes (some of which are now built into editing software).

This is not to say that you must always schlep a 15+ lb Sony 8045 as you shoot. But if you truly take your imaging seriously it is essential that you use a calibrated NTSC (or PAL) monitor during shooting and/or during the review of your raw footage to help you develop a feel for how the "true" image corresponds with the representation that you see on the camera's displays. Unless you develop such insight for your camera you will perpetually find yourself at the mercy of the camera's exposure programs and, even in manual control, you will be chasing the lights and darks in relative blindness.

About using program exposure controls. Chris Hurd, and others, have remarked that leaning on the camera's automatic exposure (and focus) system is a good, safe way to begin getting familiar with, and getting enjoyment from, your new camera. This is spot-on advice. The plain fact is that most of us bought these cameras principally for entertainment value. Most owners use them just to document slices of their lives, their families and their interests. Most owners have no aspirations becoming world-renowned filmmakers. If this describes your primary goals with the GL2 (or any camera) why not let the camera's elaborately designed circuitry do some, or all, of your work and just have a good time? There's no shame in that whatsoever.

If, however, your interests are principally of a more technical and professional nature it is essential that you learn the attributes of the GL2's primary exposure program modes -- Time Value (Tv) and Aperture Value (Av) -- and then become very comfortable using Manual mode as your primary platform.

Canon video cameras' Tv and Av modes are primarily artifacts of its line of still cameras. Tv accommodates your setting for "shutter speed" (ie. CCD sampling rate) by continuously varying the iris' size (f-stop) to meet a preset "correct" exposure. Conversely, Av accommodates your f-stop setting by varying the shutter speed to achieve this same goal. Although each has some handy applications it is important to realize that each also brings collateral programmatic consequences on the resulting image.

To answer the round-about question posed earlier in this thread, "What's wrong with using automatic exposure modes?", I would offer the rather hooked answer, "Absolutely nothing, so long as you understand, and accept, the potential consequences." For example, if someone with a bright shirt briefly walks in front the lens in a program exposure mode the camera will immediately respond by attempting to restore "correct" exposure levels. In Av, this may result in a slight change in the subjects' motion appearance as the camera changes the shutter speed. In Tv it might alter your depth of field. During the second or two that it takes the camera to readjust after the bright shirt passes out of view your scene will likely be slightly darker. Such are some of these consequences.

I really did not mean to offer such a wordy treatise...sorry about that. My primary point on this exposure topic is really to encourage you to enjoy your camera within the confines of your own applications. "Auto" is not synonymous with "dummy". But if your enjoyment of, or need for, the GL2 derives in a significant part from mastering your photography skills then turn off auto-pilot and grab the yoke with both hands by jumping into Manual exposure mode (and manual focus). By the way, the reason I keep citing "correct" with quotes is because it is a very subjective quality. The camera looks at it from a purely dispassionately digital perspective. But the camera's opinion may not always coincide with yours. You're the boss. You must always win, "right" or "wrong", in such disputes. (Hence the monitor remarks, above.)

I hope this is somewhat helpful to you and, again, I offer my apologies for being so verbose.

[Graham Bernard]

Alan, well yes-ish . . What I'm comnming around to think about is this:

1 - BENEFITS: Event shooting "benefits" from the judicious use of Auto. Yes manual exp is good for "blowing" out the background to reveal the face of a Bride. But mostly Auto is valuable . . yer don't wanna miss "that" shot . . .

2 - DO IT IN POST: Yes Auto Exp will have a lag. Think about rather "editing" this out in post. A lot of "corrections" are made by many people in post. Again if you haven't got the footage in the can when you leave the shoot then it is too late. I feel the same about Auto Focus. Sometimes leaving it on auto will at least get you that shot . . anything manual will leave you fiddling for the buttons and the shot has gone by . . just give it a thought. If a shot is thatn important, I mean this, then try and carve out sometime to get it done.

Maybe you know this already and maybe your comments relate to the postee of this thread, but I wouldn't like to think that going manual is the way . . the XM2 is good, but to have that flexibility to get the rapid eye hand coordination on this cammie is well, difficult. If you can do it and are happy going Manual full time - great!

Just had to add this . .

Grazie

[Alan McCormick]

Ken,

An excellent reply and I have now understood Tv & Av too abit more.

You have bottomed this exposure thread out nicely, for me anyway. Back to the practice mode and thanks.

Grazie,

Your point is very, very true - no shot no job!!
I take your comments seriously and will always do so, sometimes I can try too much at the same time.

Last week I went back to Autofocus for a days practice so I could concentrate on exposure only. I learn't a lot believe me, being able to change the F stop and Shutter I sussed out some of the capabilities of this Cam. There were points on review where the focus was hunting (very slightly) but at least I got the shots and I was able to concentrate on one button at a time.

ps - Off out on a Pro Cam shoot in Stratford Upon Avon tomorrow (snow permitting) and am a lecky for the day.

[Graham Bernard]

Alan, your enthusiasm just . . shines through . . IRIS wide open! - Be careful out in the snow tomorrow . . get as much "other" vid expereince as possible . .it's all great stuff.

Ken, thanks for the explanations - you always give good value . . sometimes it stays in my brain . . more often these days as I learn more and more . .

Grazie

[Alan McCormick]

Grazie,

A long but great day yesterday doing a corporate (team building) shoot with Cheema (SVS). Nice to see how it is done as a package without knowing too much beforehand ie: last minute sripting and scene setting tec. All editing on site with Casablanca.