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#1 Simon Crofts

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Posted 23 April 2013 - 06:51 PM

Hi, I wonder if you could help with some advice. I've got hold of a Canon Zoom 518, and am planning to use it at an event, to film in a low light situation. I have no experience with Super 8, or indeed with the moving image, so it's really an experiment, but I don't want to waste an opportunity, money and footage if it's not going to work out at all.

 

I've been reading the manual etc. and it seems that the lens has a range up to f1.8. I've ordered some ISO 500 Tungsten film (the subject is going to be lit by a bonfire, so tungsten balance is a good starting point). The camera can only detect up to ISO 160 film, so presumably won't detect the ISO 500.

 

What I'm thinking is that I should leave the batteries out of the camera meter, and let the camera expose without any metering at all. Is there a way of knowing roughly what the shutter speed of the camera is? I'm guessing that, since it takes 18fps, that the shutter speed is likely to be a fixed one of somewhere between 1/20th and 1/30th sec., but the manual doesn't say - is that a reasonable guess, or have I missed something?

 

Also, if there is no meter battery in, does this mean the camera should default to maximum aperture i.e.. f1.8? I've tried holding the camera up to the light and running it 'dry' without meter battery or film, looking through the lens with the shutter going and judging the amount of light coming through the shutter it looks like the lens is reasonably well open, and the meter indicator needle is resting at the f1.8 end, but am I right that it's default position for the aperture will be wide open?

 

I took some test pictures with a stills camera in a similar-ish low light fire-lit situation, and the correct exposure seemed to be within a stop or so of f1.8 @ 1/20th sec @ ISO 500. So my logic is that if I leave out the exposure meter battery then the camera will just expose wide open and shouldn't be a million miles off. My concern is that if I put in a battery for the exposure meter, when pointed at the flames the meter might stop the lens down unnecessarily or cause exposure to go up and down like a yo-yo (there's no manual exposure mode).

 

I'd appreciate any thoughts - is this going to waste a film (and worse, an opportunity when I could be filming in a different way e.g.. stills? I possible, I'm really keen to get some Super 8 of this particular moment, rather than stills.

 

Thanks in advance.

 

Simon


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#2 Simon Crofts

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Posted 23 April 2013 - 06:58 PM

p.s. may try to take a 2 stop ND filter too to give flexibility.


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#3 Mark Dunn

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Posted 24 April 2013 - 06:01 AM

The shutter speed will be about 1/36 at 18fps as the shutter angle is probably 180 degrees. A camera with 'XL' in the name would have a 220 shutter and so give about 1/30.

You can't work without a meter- there's no telling what the camera meter will do without batteries. So without manual and  a separate meter, it's all but unusable with the fast film.


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#4 Simon Crofts

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Posted 24 April 2013 - 06:24 AM

Thanks Mark, that's really helpful. Manual and a separate meter would be great, but I don't want to buy a new camera for it just at the moment. I might for the next time round if I enjoy the experience. I'll have a separate meter with me in the sense of a stills camera with me, so I'll know whether 1/36th @f1.8 @ISO 500 is usable or not - if that's what the camera's giving me.

 

I was just trying it in bright sunshine (with no film) and again, as far as I can tell it looks like, with no battery in, that it's default is exposing at full aperture. There's no sign of anything like aperture blades appearing when I'm running frames (though I'm not sure whether the aperture blades would look the same as in a stills camera) and no sign I can see of the lens stopping down - bright image and I can see to the edge of the lens barrel all the way back. I still have a bit of hope that it may just be running at f1.8 and that the camera meter with batteries out might not be interfering with that.

 

I guess an alternative approach might be to put a battery in, and hope that the camera treats the 500T as 160 film. At least then it will only start to stop the lens down if the flames get really bright in the frame. The main thing I want to avoid is the camera stopping down unnecessarily because of bright lights (flames) in the frame.


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#5 David Cunningham

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Posted 24 April 2013 - 08:08 AM

You are going to need to put a battery in it.  My understanding with that camera is that the aperture will lock to it's last position and not move if their are no batteries.  It's possible that it's fully open now, but there is no way to know for sure.

 

I would expose 500T in that camera using the built-in meter in your situation.  It will set the aperture based on 160 as long as you flip the switch to tungsten to keep daylight filter removed.  That's only just over 1.5 stops over exposed which should be fine and actually good in that case since the fire will throw off your metering and cause your subjects (people) to be way under exposed.

 

Alternatively, you can test the aperture by inserting a battery and then pointing the camera at a bright light while you look into the lens.  Watch for the aperture to close down.  If it does, take it into a black room where it will open wide.  While in that room, remove the battery.  Then, take it back to a bright light and see if you can confirm that the aperture is wide and stays wide open.  If so, that's probably the best way to shoot a firelight scene like you are trying to do.

 

Now, all this assumes that the meter/aperture setup is in full working order.  If there are any loose, worn or deteriorated (rubber, etc) parts inside you will have erratic results.

 

Remember that those batteries are 1.35v and not 1.5v.  Use of a 1.5v battery could damage the meter and will certain give inaccurate results.  There are many sources for these Weincel batteries.


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#6 Will Montgomery

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Posted 24 April 2013 - 09:45 AM

Here's the thing. If you are shooting something lit by a bonfire, and the camera will interpret 500T as anything less than 500T, then the aperture will mostly remain open at 1.8 so which will probably be where you'll want it anyway. So in other words, don't worry about calculating or disabling anything, just slap in some 500T and shoot away. With the negative stock you'll have more freedom in the telecine stage to get what you can out of it. If you can get a manual exposure camera you might be better off but not by that much.

 

I would expose 500T in that camera using the built-in meter in your situation.  It will set the aperture based on 160 as long as you flip the switch to tungsten to keep daylight filter removed.  That's only just over 1.5 stops over exposed which should be fine and actually good in that case since the fire will throw off your metering and cause your subjects (people) to be way under exposed.

Exactly. Only place there will be enough light is the center of the flame so everything else will be underexposed even if the meter could handle 500T.


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#7 Mark Dunn

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Posted 24 April 2013 - 09:59 AM

You don't view through the aperture- the beamsplitter for the viewfinder is in front- so you get no indication of aperture. I agree that the fire probably won't affect the meter so I would not try to disable it.


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#8 Simon Crofts

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Posted 24 April 2013 - 12:58 PM

Thanks folks, lots of interesting and useful thoughts there.

 

You don't view through the aperture- the beamsplitter for the viewfinder is in front- so you get no indication of aperture

 

 

I was looking through the lens with the cassette door open so I can actually see what is hitting the film, rather than through the viewfinder. With the cassette door open, and a bright light in the right place, I can look through the lens in two directions through the flickering shutter. From the back I get a slightly oblique view, but can still see the subject through the lens and it seems to be open.

 

It's a good plan about putting batteries in and using in a dark room then removing batteries to make sure it's opened up the aperture.

 

Also a good plan to leave the batteries in and rely on the 160/500 ISO different to stop it shutting down - but I want each sequence filmed without the exposure changing in mid sequence, even if bit of it end up being overexposed. Basically I need a camera with manual exposure, but am hoping to manage with what I have for this experiment at least.


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#9 Mitchell Perkins

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Posted 24 April 2013 - 02:19 PM

I've tried holding the camera up to the light and running it 'dry' without meter battery...and the meter indicator needle is resting at the f1.8 end

 

 

Battery power works against an aperture sprung to rest at f1.8

They wouldn't use anything more involved for a simple camera

Some are sprung to rest at the other end, not yours though

 

Take the batteries out. The aperture will start shutting down if there's enough fire in the frame

OTOH the flame itself will blow out with 500T...

 

Mitch


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#10 Simon Crofts

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Posted 24 April 2013 - 02:37 PM

OTOH the flame itself will blow out with 500T...

 

 

Looking at stills I've taken of fire recently I was coming to the same conclusion. It's not likely to be possible to retain detail in the flames and the people dancing around them. Generally the people are more important than the flames. But to give a little bit of flexibility I was planning to take some 200T film that I happen to have handy too. I'll choose which one to use based on the results from the (digi) stills camera. Ideally also a neutral density filter (in fact, a polariser), though I'm not sure I can find one with the right thread size in time.

 

I'm not aiming for technical perfection, more of an impressionistic effect. But I don't want everything completely blown or blocked up either. And hoping that the latitude of the negative film stock will make up for mistakes.


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#11 Simon Crofts

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Posted 24 April 2013 - 02:40 PM

Looking at stills I've taken of fire recently

 

 

 

Sorry, just to clarify, I meant I was looking at the EXIF data of aperture/shutter speed/ISO combination taken of and near flame. There's a risk that 500ISO may actually be a bit too fast.


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#12 Simon Crofts

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Posted 24 April 2013 - 03:03 PM

In case anyone's interested, this one taken a few days ago was at ISO 640 f3.2 1/60th: 

 

http://beltanefireso...imon-crofts-01/

 

The fire is blowing out to some extent, and it's effectively 1.5 stops less exposed than f1.8 iso500 1/36th.

 

Maybe I should go with the 200T film.

 

Sorry, just thinking aloud!


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#13 David Cunningham

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Posted 24 April 2013 - 08:55 PM

If that's the results with a digital camera, I would bet 500T would capture more details in both dark and bright highlights.  It's a great shot though!


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#14 Mitchell Perkins

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Posted 26 April 2013 - 04:09 PM

"I'm not aiming for technical perfection, more of an impressionistic effect."
 

I love it when it's like that!

 

"But I don't want everything completely blown or blocked up either."

 

Maybe you want batteries in, and just make sure there's no flame in shot when you want faces/bodies.

You could even use the fluctuating aperture for extra impressionistic effect.

 

"And hoping that the latitude of the negative film stock will make up for mistakes."

 

Yes. Yes it will.

 

Mitch


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#15 Simon Crofts

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Posted 28 April 2013 - 06:39 PM

Thanks folks, I'll see how it goes, fingers crossed!

 

Simon


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#16 Phil Rhodes

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Posted 29 April 2013 - 02:15 AM

I hate to be the harbinger of doom here, but if he tries to shoot night exteriors on 500ASA film, isn't it alarmingly likely that he'll get a black frame punctuated by occasional flickers of flame?


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#17 David Cunningham

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Posted 29 April 2013 - 09:22 AM

I hate to be the harbinger of doom here, but if he tries to shoot night exteriors on 500ASA film, isn't it alarmingly likely that he'll get a black frame punctuated by occasional flickers of flame?

 If it's a significant bonfire and his subjects are close to said fire... and he's wide open...  he'll slightly blow out the center of the fire and probably get decent facial definition and an idea of the clothing, etc.


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#18 David Cunningham

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Posted 29 April 2013 - 09:28 AM

Not sure what this was shot on... but definitely looks like film with no other light on the subject but the fire.

 


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#19 David Cunningham

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Posted 29 April 2013 - 09:31 AM

Also:  

 

Definitely shot on film by Cinelab's Robert Houllahan.


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#20 Simon Crofts

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Posted 29 April 2013 - 01:03 PM

isn't it alarmingly likely that he'll get a black frame punctuated by occasional flickers of flame?

 

 

Thanks for posting the examples, that's interesting.

 

I'm hoping that the Super8 negative film will behave much the same as stills film in terms of exposure values - and I'll be doing plenty of still frames (albeit on digital, but with reasonably high dynamic range) before using the Super8. So provided the exposure is correct for the digital, then the same exposure values (equivalent combination of ISO/Aperture/shutter speed) should be good for the Super8 too. I won't be able to finesse the Super8 exposure since I'll rely on switching ISO film rather than stopping the aperture down, but I should at least be able to pre-visualise the effect I'm getting at a particular exposure (and I think that even if I could change the aperture, I'd likely be using it wide open all the time anyway). The bonfire should be pretty bright because it's quite a big one so there should be plenty of illumination from it. But there is definitely going to be very high contrast and a fast fro-off into oblivion for subjects more than a few metres from the fire, so there'll be blowing out of highlights and blocking up of shadows. Hopefully the effect might work though


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