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Exposure System for Canon 518


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#1 Chris Blotiau

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Posted 03 February 2012 - 11:52 AM

Hi,
I recently purchased a Canon 518 super 8 camera (http://www.canon.com...n&page=1956-197) from ebay. I bought kodak's 100d color reversal film, popped it in the cartridge holder and off I went shooting. Foolishly, I did little research before hand and only did a brief scan of the original manual that came with the camera. After getting my developed film back from Pac Lab in Manhattan I was eagar to watch it on my newly aquired Bell and Howell projector, regards of Craigslist and the nice gentleman a few towns over.
I found that nearly all of my outdoor footage was overexposed to the point where no image could be made out, and only some pieces of the outdoor footage I could just make out the subject matter through the blown out whites. It was a semi bright day, but by no means a full 100% intensity sunny day. To my consolation, some of the film was beautifully developed, but only what I had filmed indoors.
This prompted me to do some research and I started with the camera's manual. I discovered that the camera had a small pin attached to the trigger handle and it had been in the tungsten setting for the duration of my shooting since I hadn't even known it exsited until after I watched my first 2 rolls of developed film. (*I know now that this pin shouldn't make a difference because I'm using daylight balanced film which automatically disables the built in filter), but at the time I thought I discovered the problem to my exposure woes.
Again I went out with my camera and more 100d film for another two rolls. I would disable and enable the built in filter via the pin attached to the trigger. I thought for sure I would have properly exposed film now that I was paying attention to this filter. Again, however I received my film back from Pac Lab to discover very few clips worth keeping, and the properly exposed pieces were all indoors. I was frustrated and annoyed.

**This is a key piece of info that hopefully you all can help me clear up...

I had been neglecting the button battery compartment which powers the electronic eye for my first two trials (4 rolls of film) because I noted that 1.3v mercury cell batteries were needed (I thought it just powered the light meter, and not the entire auto exposure system). I knew these were near impossible to attain, and in addition, the modern button batteries of similar size were rated at 1.5 volts. By now I had it with my exposing problems and decided to put the 1.5 625a batteries in there assuming it would be better than nothing. Now the light meter works when I look through the view finder, and it often warns that I'm overexposed, but I'm worried that the difference in voltage is still a problem.

Today I was told by someone at Pac Lab that it is possible my camera was shooting with the aperature wide open since all along I had been shooting with no batteries to charge the electronic eye. Do you think so ? It makes sense to me, because most of my outdoor footage is completely blown, and the only good stuff is from inside. I'm going to by wein cell batteries from myoldcamera.com, but do you think that now I will have a problem with my indoor exposure with daylight balanced film ? I've learned so much already, but I'm still very confused. Any help would be greatly appreciated.

Chris
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#2 Jason Burlingame

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Posted 03 February 2012 - 02:49 PM

Hello Chris,

Your problem is obvious your daylight exposures have too much light going in to the camera and therefor over exposing your film. Now the reason why this does this is because two factors:

#1 your shutter speed has a 160 degree shutter angle so your shutter speed is 1/40 of a second.

#2 ASA rating of 100 in daylight at 1/40 of a shutter speed is a lot of light coming in and over exposing your film. Even if your aperture is at f.16 which is the smallest f-stop for your camera that is still a lot of light overexposing your film.

Solution: Get a ND filer that fits your camera lens thread. You can go to any camera store and they will be happy to find a size that will fit your camera. Read up on ND filters on the link I provided. This like putting sun glasses on your camera so that you get a proper exposer. Every pro I know uses these when they film outside in daylight with high ASA.

Remember: These cameras were made for consumers in mind, if need to film in daylight you would buy kodachrome 40 ASA, and that is what your camera, my cameras, and most cameras that were designed for. If a consumer back in the day wanted to film indoors they would buy a higher ASA film such ASA 100 or 200 ASA. It truly was that simple back then. That is also why you get better exposure indoors because there is not as much light indoors compared to the SUN. If you compare your house artificial light to daylight you will see that the daylight from the sun is a lot brighter.

My recommendations: Learn all about exposure as much as you can. Read a lot online, even take a traditional black and white photography class that allows you to use real film and allows you to develop and process it yourself, that is where most of my experience came from when I first learned to shoot Super 8mm, 16mm, and 35mm film. If you can't get a class then learn with a 35mm SLR camera and get your film processed at a lab. To truly love film use most first know how to properly expose film correctly. If we lived in the same area I wouldn't helping you out in person. If you have any more questions just ask.
PS: Learn shutter speed, ASA, aperture, and even ND filter and how they all related to giving you a perfect exposure

Always in a lines work to help a fellow filmmaker.
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#3 Jason Burlingame

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Posted 03 February 2012 - 02:56 PM

To learn how I calulated shutter angle to shutter speed.

(fpsx360) / Sutter Angle


example:

(18X360)/160

6480/160

is 40.5

round to the closest shutter speed that is 1/40th of a sec.

and that is your shutter speed from shutter angle
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#4 Chris Blotiau

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Posted 03 February 2012 - 04:47 PM

Outstanding ! Thank you so much Jason !!

Still, the question of the button batteries is curious to me. Are they infact responsible for controlling the auto iris within the camera, or does this "auto aperature" work even when the 1.3v batteries aren't there ?

I have a foundational understanding of exposure and how it relates to picture quality, the problem arose with all the new variables this new/old tool brought into play. I'm confident with a modern camera where I can manually set the shutter speed, aperature, and so on, but in the case of the super 8 I had no idea what the camera was doing, and what was responsible for the huge amount of light being allowed through. Thank you for your help, following this reply I will be doing a lot more research on the suggested topics.

By the way, I'm located on Long Island wouldn't mind some shooting with a vet if you're nearby. Thanks again.
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#5 Jason Burlingame

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Posted 03 February 2012 - 09:50 PM

The two 1.3v cells are responsible for the Built-in light meter that works with the auto exposure. Auto will not work if the 1.3v cells aren't present. However, if do not use the cells you still can manually adjust the f-stops with the slider "M" on leftside of the camera, you will need a external light meter to get an accurate exposure.

As far as modern camera did you mean DSLR or 35mm SLR. Digital and film have no comparison in my opinion and experience. I hope you were refering to modern film cameras, and if so I am glad that you have experience with film and this will only make things a lot easier.

By the way I unfortunately live in California, but you can reach me here. I also hope you have a fun experience using super 8 and getting proper exposure.
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#6 Chris Blotiau

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Posted 03 February 2012 - 10:14 PM

Ok, so as I suspected, those batteries are key. I don't know what slider you are referring to with the letter "M" on the left side of the camera. The only thing I can change is the foucus, zoom, internal filter via trigger pin, and the lock for the shutter. I noticed f-stop numbers on the focusing ring, but I hesitate to believe this has anything to do with aperature, because one of the first things I did with the camera while shooting indoors was film myself turning that focusing ring in the mirror so I could see a change in the final picture if there were any. The final projection is a clean, perfectly exposed shot of me looking in the mirror through the camera turning the focusing ring and nothing at all changes; not the focus or the exposure. Is it possible you are thinking of a different version of my camera ? I know of a Canon 518 XL and a Canon 518 Auto Zoom, I believe there is another version as well. Mine is the earliest, and I believe the simplest of these models.
I was actually referring to digital SLR, but my knowledge of exposure comes from working with 35mm cameras in a college class where we were taught basic principles and developed our own film. Why do you think digital exposure is so different ? Does it not operate on the same principles of shutter speed and aperature, ISO, etc ?
Regardless, your help has been so valuable to me. Thank you again so much for taking your time to read my posts and answer questions.
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#7 Jason Burlingame

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Posted 03 February 2012 - 11:13 PM

I was hoping you had a later zoom 518 so never mind about that. This model will not allow you to manually set the fstop. Those so called f-stop numbers are not f-stop numbers. They indacte the distance between the camera and the subject. Green is Feet (ft) and black is meters (M). The other numbers are for the zoom. Your f-stops will be in the viewfinder with the needle indacting what f-stop you have. here link to a manual in PDF it is very helpful and it also talks about the right filters to use. Manual link
I will get back to you on the DSLR vs film SLR later have to do a few things. Let me know if that manual helped

also that shutter function, only allows you to lock the shutter not change the shutter speed. The manual will explain

Edited by Jason Burlingame, 03 February 2012 - 11:14 PM.

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#8 Bryson Malone

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Posted 11 August 2014 - 01:18 AM

This conversation has been so helpful! I just bought a Canon 518 auto zoom and some kodak 50D film. I shoot with a 35mm film camera so i understand metering. In the post, Jason mentioned that the ASA rating of 100 would overexpose even at f16. The 50D is ASA 50 so that will be less of an issue, but at 1/40, even ASA 50 will likely be overexposed in bright daylight. I am going to Yosemite to film rock climbing in bright daylight tomorrow so just some short advice would be much appreciated. 


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#9 Andries Molenaar

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Posted 11 August 2014 - 03:50 AM

Put an Neutral Density filter of 8x (3 stops) on. Make sure the exposure system works through the lens otherwise reduce the ISO value.

 

If the camera exposure system is on ISO 100 it will underexpose a film of ISO 50.


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