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#1 Andrew Jackson

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Posted 17 March 2006 - 10:27 AM

Hey all! I'm currently enrolled in school, majoring in cinematography. This semester is my first production course, and I've learned much so far! We are shooting our final films on Super 8. I have a Minolta D4, but there seems to be some problems I'm having and I was wondering if any of you could throw me some advice...

First of all, I went and got me a 18% gray card. I'm using reversal stock, and plan on using Tri-X (EI 200D) for indoors and Plus-X (EI 100D) for outdoors. First, there seems to be a problem with my built in 85 filter. When I screw the screw in the top of the camera to push it out of the way for shooting indoors (to get the 2/3 stops more light), my lighting meter goes wacko. It starts jerking around, and will never go below a 4 even if you go into a dark closet with no lights. So, anyone know what the deal is? It wouldn't hurt me to just have the filter in there really, I was just wondering if this is fixable or if anyone knows what is going on?


Another thing involves the gray card I bought. I bought it from a popular photography store in my area, so I trust it. The problem is that I'll take a reading off my main actor's face, and get a 5.6 (this is all the way telephoto on his face) and when I have him hold the gray card in front of his face, I get the same reading! He is white, so this should be about a stop difference, but it's not! Oh, by the way, I'm using the reflective light meter that is in my camera. I don't know what is going on, and it's wierd. When I got home and had my mother (haha) help me test it out, it worked SOMETIMES, but there were still issues. I had to shoot the other day, so I just did many takes. I did one with locking the aperture a stop lower to get a bigger opening than what I read off his face so that hopefully it turns out ok. I'm still not sure though, and I really need it to turn out. The other takes I did was at the same stop I was reading at his face. And then I did even more by just letting the exposure stay on automatic and have it do what it wants as he moves through the scene...


This brings up some more questions, lol. For wide shots, it is recommended not to lock the lightmeter at any certain f/stop, but how "wide" is a wide shot? I'm trying to understand how it would take readings. Since, if you take an entire shot thats full of really dark objects, and you have your camera at automatic exposure, everything will appear 18% gray. Well, if you have a wide shot of many different objects of different brightnesses, what will appear 18% gray? Does the averaging that the meter does on wide shots just take the objects inbetween the brightest areas and darkest areas and expose them at 18%? I feel like Hollywood here more than a film student, I did about 6 takes of everything, but I can't keep doing this. My actors that aren't getting paid were getting a little angry and I don't have that much money for processing :P. There were some shots that were from my actor's chest to the top of his head (MCU) and I did a take with having the meter at automatic, then locking the meter at what his face read, and then locking the meter at a stop lower than what his face read. Which one would have been sufficient? I wasn't really sure about how "wide" was wide and exactly how the meter averages the light. The most important feature in the shot was his face, and that is why I based my other two shots off the readings there. I don't even use my gray card anymore, because it doesn't seem to make a difference...


Thanks for all your help guys! Any suggestions would be greatly appreciated
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#2 Gareth Munden

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Posted 17 March 2006 - 11:03 AM

What school are you at ? that you have too ask such things . First think don't your teachers know ? . WOW glad I went to school in the UK , Teachers have some idea about the subject they are teaching here . If you are serious about Cinematography buy a light meter , with a pen and paper some and some tests even a very cheap stills meter will get you there .

Good Luck .
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#3 Alessandro Machi

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Posted 17 March 2006 - 12:20 PM

The light meter in your camera has to be reliable. Reliability is even more important than accuracy. What I mean by that is you need to trust that your meter will always read the same situation the same way. This allows you to learn in what situations you can trust the meter and simply lock off the exposure, and what situation you must override the automatic meter.

This is worth repeating, you have to trust the meter in your camera as a starting point even if you don't trust it for your final choice. By the way, always put your camera on a tripod when doing exposure tests to make sure the frame isn't changing as you do your exposure tests.

I don't agree that you don't lock off the light meter in a wide shot as your exposure reading could fluctuate wildly depending on how much your backlight changes during the shot. If actors are moving during the shot or the camera is panning the background brightness can change and that will affect the metering if the metering is left in auto. When you have a shot with a huge contrast range, I am a fan of getting the exposure correctly on what you feel is the most important aspect of the shot, this usually (but not always) is the actors face.

If you can trust the autoexposure meter for certain situations, your instincts are right that in certain situations leaving the camera in autoexposure might be the best choice. If you determine that the auto-exposure meter on the camera is not reliable, I would not trust the camera. Does this camera have it's own battery for the autoexposure meter? Maybe it needs to be replaced.
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#4 Andrew Jackson

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Posted 17 March 2006 - 12:56 PM

Thanks Alessandro Machi, your reply was much more helpful than the other. My story is this: My teachers know what they are talking about, but I'm on Spring break this week and I thought instead of trying to call them and bothering them over Spring break, I could come here and get more people's opinions. This board is for that, no? I have already asked my teachers about my lightmeter locking up when the 85 filter is moved out of place, and they do not have an answer for me. If you went to the UK and learned from such greats, then why did you not have any answers for me?


The other issue is that I could only get a Belle and Howell camera (spelling is probably off) for my lighting test roll that I did. It is an automatic camera, and you cannot even see what the lightmeter is reading as it is suppose to be just a point and hold button camera. I bought the minolta because I figured I would learn more. I've been looking into lightmeters, and I will need to buy one next year, but this year I did not have the time to shop, or the money, and I felt there was no need as I could trust my built in lightmeter, but obviously that appears to not be the case.


I understand that the reading could fluctuate as I move the camera if I need to move it in the shot. I read in a book (I can't recall if my teacher said it or not) that for wide shots it is not typically necessary to lock the meter, but again I ask, how wide is wide and how does the meter work in these situations? It did not explain past what I just said. And I agree, it doesn't make sense because you could move into a brighter lit area. I ask though, How does it "average" the light to get it's reading? I assume it takes in consideration the darkest and lightest points, but if so then when the film is exposed, do the areas between the brightest and darkest reflectance look middle gray? I'm all about understanding how every little thing works so I can be better. The teachers probably explained this, as they have worked on many films themselves, but I'm on Spring break and away from my notes, I can't remember fully, and I do not feel like bugging them over Spring break. Please hold your insults and do not post if you have nothing useful to say. Thanks.

Oh, by the way, I was using a tripod :S. I really think my meter might be screwy. And my camera uses like 4 double A batteriers for the meter and for running the film. Also, understand that this is my first production class and the first time ever shooting anything on film. Teachers try to simplify things for students in the first production class - this makes sense, yes?

Edited by Andrew Jackson, 17 March 2006 - 01:05 PM.

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#5 Alessandro Machi

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Posted 17 March 2006 - 01:45 PM

I'm not a hundred percent sure but I think the Super-8 autoexposure meters from the late 70's probably averaged out the brightness over the entire viewfinder area.

The only time I would trust the automatic exposure meter (and again, assuming the auto meter is working) is if my shot is primarily a front lit shot and I don't have to worry about an intense back light suddenly hitting the lens and fooling the light meter in the camera.

When using autoexposure, I believe it doesn't really matter how wide the camera frame is on your subjects, what matters more is if the lighting is frontal or backlit. But even then, if your front light is the sun and it's behind trees so as to create hot and dark spots, there really won't be one magical exposure setting that will get everything in proper exposure because the difference between the hot spots and the dark spots is just too great for a reversal film.

The safest approach to take is to zoom in on your actors face and take a reading. If you have more than one actor, take a reading of each actor face, one at a time and see how much f-stop difference there is. At which point you have to decide what you think, lock the expsoure where it is or over/underexpose it by a half stop to 1.5 stops.
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#6 Alessandro Machi

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Posted 17 March 2006 - 03:03 PM

You might be able to use a video camera to help you with your super-8 f-stop choices. If the video camera actually tells you what the actual f-stop reading is, you'll then need to do some calculations to get the video camera aligned with your film stock sensitivity.

Video cameras are probably rated around 250ASA, the newer cameras perhaps 400ASA. If I'm wrong please pipe in.

Once your video camera goes into gain mode you'll have to factor that in and unfortunately most lower cost video cameras don't tell you how much gain they are actually using, you can tell the camera is in gain mode by the increased amount of grainiess in the viewfinder, but comparing gain to ASA is difficult if you don't know how many db of gain is being used.

Do one test cartridge as soon as possible and you should be able to find a relationship between the reading you get on a video camera and what you'll need to set your film camera f-stop to.
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#7 Andrew Jackson

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Posted 17 March 2006 - 05:50 PM

You might be able to use a video camera to help you with your super-8 f-stop choices. If the video camera actually tells you what the actual f-stop reading is, you'll then need to do some calculations to get the video camera aligned with your film stock sensitivity.

Video cameras are probably rated around 250ASA, the newer cameras perhaps 400ASA. If I'm wrong please pipe in.

Once your video camera goes into gain mode you'll have to factor that in and unfortunately most lower cost video cameras don't tell you how much gain they are actually using, you can tell the camera is in gain mode by the increased amount of grainiess in the viewfinder, but comparing gain to ASA is difficult if you don't know how many db of gain is being used.

Do one test cartridge as soon as possible and you should be able to find a relationship between the reading you get on a video camera and what you'll need to set your film camera f-stop to.


Awesome suggestion!

My film project is coming down to the line. I already shot some stuff and I'm sending it off tomorrow or Monday for processing. If they turn out ok then I'll know how to work my camera, but the video camera is a good idea. I have one, but I've never delved into the manual controls as I never really needed to. I'll have to check it out.
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#8 Hal Smith

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Posted 21 March 2006 - 02:53 AM

Awesome suggestion!

My film project is coming down to the line. I already shot some stuff and I'm sending it off tomorrow or Monday for processing. If they turn out ok then I'll know how to work my camera, but the video camera is a good idea. I have one, but I've never delved into the manual controls as I never really needed to. I'll have to check it out.

I'm too late for this project with this advice but B and H Photo sells new Sekonic L-208's for $94.95. They're a pretty decent little incident/reflected meter and you can expect a brand new meter to be pretty much on the money (if anyone reading this post knows of another relatively inexpensive new incident/reflected meter please chime in). They don't have cine speeds per se which means you have to calculate actual cine camera shutter speed, not a difficult task and great for learning what's really going on with the relationship between film frame speed (FPS) and shutter angle. Shutter speed = (1/FPS) X (shutter angle/360)

You might look around for an old Spectra Candela or Combi meter on the web but the problem there is you might get a good one, and you might not. If there's at least one known good meter at your school you could chance it on an old Spectra, if it's a bit off you could just lie to it by offsetting the ASA scale.

The advice to use a video camera is good advice but I have had some problems with predictable exposures shooting under difficult lighting situations. My Sony miniDV supposedly has a quasi-spotmeter mode but it gets fooled real easily by strong stage lights, etc. I've resorted a couple of times to manual exposure watching highlights. Next time I use it for a project that matters I'm bringing a waveform monitor along so I can directly judge video exposure value.

Edmond, OK
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#9 David W Scott

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Posted 21 March 2006 - 05:01 PM

I'm also too late for your project, but here's a couple of things to note:

You were getting the same lightmeter reading from your friend's white face and from the 18% grey card because 18% grey will approximate the light reflected off a white person's skin. So, it simply means that your light meter is accurate and that your friend has average caucasian skin tone. If you are filming someone of any other complexion (i.e. darker skinned), you may need to open up the aperture a little more.

Your internal light meter will be averaging the exposure for either the whole frame, or it will be weighted towards metering the centre of the frame. You can tell by aiming at a really bright object against a darker neutral background. First, centre the camera on the bright object. Then, wiggle the camera around. If the internal meter immediately drops down when the bright object is not perfectly centred, then you have a centre-weighted meter. If the meter does not drop down until the bright object starts to go out of frame, then you have a frame-averaging meter. Once you have decided which kind of meter you have, you can judge more accurately what the camera is metering for.

No matter what kind of meter you have, the best thing to do is to zoom in on your subject to get a more accurate reading. Of course, if your goal is to simply expose the faces correctly, then zoom in on the faces, set and lock the aperture, and zoom out to your desired frame. To get a better idea of how your final image will be exposed, zoom in on different parts of the frame. Zoom in to the darkest shadow, and note what the aperture reads as. Zoom into the brightest highlight, and note what the aperture is. Zoom in to the subject that you would like to expose for (or anything that is the same colour and in the same lighting) and note what the aperture is. With these three numbers, you will be able to answer some questions: Are my darkest or lightest areas radically different than my subject? How much of the final frame is like the darkest, lightest or middle exposure? If you are shooting reversal film stock, there is very little leeway for exposure. If your brightest or darkest areas are more than 2 or 3 f-stops different than your subject, they will begin to disappear into blacks and whites. If you are shooting negative stock, you have a lot more leeway, and will be able to see deeper into the shadows and highlights. The formal way to control exposure in this manner is called "the zone system". You needn't be as rigorous as the "zone system" but it is a great way to think about exposures and consider your choices as more than a single f-stop setting for a whole shot. Looking at your exposure this way is especially important to achieve the look you want when you are shooting wide shots. (By wide shot, I mean anything where you can see a full human figure or more.)

If you can get a cheap external meter, they are very useful. You will most likely get an incident meter, which means that the meter is designed to be held where your subject will be. The light that falls on your subject should fall on your meter, with it facing towards the camera. To get a better sense of the lights and darks in your exposure while using an incident meter, you will need to walk around the shot, metering in the darkest areas and the brightest (basically, walking around to the same places I had you zoom in to when you used the internal camera meter above.) Everywhere you take a reading with the incident meter, it should give you the same reading as though you had held an 18% grey card in that spot and zoomed in to check exposure with your camera.

There are lots of resources out there, plenty to get you up to speed quickly. The most useful ones for you at this point will actually be books on still photography. They will get you up to speed on metering and exposures. I also recommend Lenny Lipton's book, if it's not already on your syllabus.

Best of luck,

Dave

Edited by David W Scott, 21 March 2006 - 05:05 PM.

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#10 Alessandro Machi

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Posted 21 March 2006 - 06:20 PM

I don't thing that a caucasian face approximates 18%, if it actually does, than I would think most meters in Super-8 cameras are using some other average.

Usually I have found that when I zoom in and get a reading on a caucasian face, I need to open the f-stop 1/2 to 1 f-stop. If the lighting is super-soft, perhaps opening up only 1/2 stop is all that is needed.

And a black person would not need not need to have the f-stop opened up even more if one zooms in on their face, if anything, they would need to be compared to the background at which point the f-stop might need to be lowered a 1/2 stop, maybe 2/3, maybe a full stop.

The in camera meter gets one close, but I have found in general that a little additional manual expsoure tweaking is probably required when one is trying to get an accurate reading off of an actors face.
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#11 David W Scott

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Posted 21 March 2006 - 07:47 PM

I don't thing that a caucasian face approximates 18%, if it actually does, than I would think most meters in Super-8 cameras are using some other average.

Usually I have found that when I zoom in and get a reading on a caucasian face, I need to open the f-stop 1/2 to 1 f-stop. If the lighting is super-soft, perhaps opening up only 1/2 stop is all that is needed.

And a black person would not need not need to have the f-stop opened up even more if one zooms in on their face, if anything, they would need to be compared to the background at which point the f-stop might need to be lowered a 1/2 stop, maybe 2/3, maybe a full stop.

The in camera meter gets one close, but I have found in general that a little additional manual expsoure tweaking is probably required when one is trying to get an accurate reading off of an actors face.


Of course, you are right. :rolleyes: I shouldn't rely on memory for these things!

I went back to Chris Malkiewicz ("Cinematography") and he says that a Caucasian has 35% reflectance and a black face less than 18% (varying of course by skin tone.) So if you are metering off their faces, the white face needs at least half a stop more to keep from darkening to grey, and the black face needs at least half a stop less than metered to keep it from lightening to grey.

That's how I confused myself though.... I was thinking about metering with an incident meter, or using a grey card. In which case, you might need to open up a touch to get a nice exposure on a black face.

Sorry for the confusion!
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#12 Andrew Jackson

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Posted 22 March 2006 - 03:08 PM

I appreciate the replies. The things that scare me though is that my friend's skin is fairly pale, and I am zoomed in all the way when reading his face and my grey card. There is not even the slightest difference. I asked about it in class and I was told to get my film back and check the results. It could be, since the grey card is flat and his face is not, some shadows doing some funky things with the meter, or the texture of his face. I was expecting at least a little bit of a stop difference, but I was told that if my meter is not working properly, not to worry about the one stop or so difference and that I won't be graded harshly for it. It just makes me angry because I'm trying to learn this stuff and it just makes things more confusing when they don't work like they are suppose to :P
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#13 Alessandro Machi

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Posted 23 March 2006 - 01:50 AM

I was thinking about metering with an incident meter, or using a grey card. In which case, you might need to open up a touch to get a nice exposure on a black face.

Sorry for the confusion!


And that makes a lot of sense as well.

I think you've identified a dual but opposite reality that probably exists when comparing Super-8 metering methods to 16mm and 35mm metering. If one can trust their Super-8 in-camera reflective meter to be reliable (although not necessarily accurate) it can make the job of setting exposure quick and almost easy. But the reflective meter in Super-8 cameras causes terms to be used in a different way than when one is using an incidental meter in 16mm or 35mm.

16mm and 35mm cameras usually don't have an in-camera reflective meter so opposite explanations are used to explain the same thing such as opening up exposure on a black person if one is using an incident meter, yet if one is using a reflective "in camera" meter, than the exposure would actually be closed down slightly yet both methods could end up with the identical f-stop reading if the metering is done correctly.



I appreciate the replies. The things that scare me though is that my friend's skin is fairly pale, and I am zoomed in all the way when reading his face and my grey card. There is not even the slightest difference. I asked about it in class and I was told to get my film back and check the results. It could be, since the grey card is flat and his face is not, some shadows doing some funky things with the meter, or the texture of his face. I was expecting at least a little bit of a stop difference, but I was told that if my meter is not working properly, not to worry about the one stop or so difference and that I won't be graded harshly for it. It just makes me angry because I'm trying to learn this stuff and it just makes things more confusing when they don't work like they are suppose to :P


You probably know this already but many super-8 cameras shut down the auto exposure meter when the trigger is no longer depressed. Even though the camera switch is "on", if the trigger is not halfway depressed, the auto exposure meter may simply stay "stuck" in the same f-stop position it was in when you did your original f-stop reading.

Also, if your camera's f-stop reading is 'wide-open" when you did your first auto exposure meter reading, it's possible that the meter won't move when you switch to the grey card because there just is not enough light.
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#14 Andrew Jackson

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Posted 23 March 2006 - 08:13 AM

I thought at first it might not be enough light, but then I blasted a 600 watt quartz-halogen light straight on the person and still did the same thing. My teachers also told me to depress the trigger some to see if there was a difference, and take the film out and try actually running the camera, but it is the same reading as when the camera is just set to the 18FPS position and on the individual without pressing the trigger.


It is quite confusing. I sent off some film Monday by priority mail. I'll post on what it looks like when I get it back and project it.
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