Is there a good tutorial to understand the relationship between aperture & shutter?

T

Tom Films

Active member
Is there a good tutorial to understand the relationship between aperture & shutter?

Disclaimer: Newbie venturing outside the green box.

I am looking for a good source or explaination of the relationship between aperture and shutter speed. I understand how aperture affects DOF, but what I don't understand is how the two relate to how bright the image is.

It seems in playing with the A1, I am unable to get a bright enough image without dropping my shutter to the point of ghosting the image.

It is my understanding the idea is to adjust the settings to satisfy the mark on the cameras light meter. Correct? I was told a mantra for shooting in outdoor bright snow conditions is: "When in snow, let it go" which means 1-2 settings above the light meter mark.

I know I don't understand these manual settings well enough, but in order to do that, I have to drop the shutter far too much. How do I increase the brightness without setting the shutter too low?

Do shutter speeds affect the look of the image? If I am trying to acheive a film like look at 24 frames, what is the best shutter speed? When shooting fast moving subjects (30+ mph) what a good shutter?

It seems like if I want a 1/60 shutter, it's not possible to adjust the aperture enough to get a well light image.

I know I am doing this all wrong and as newbie its entirely overwhelming. Any tips to set me straight?

Thanks
 
Well, you need to check whether your ND filter is engaged. Doesn't make sense that even at full wide (f1.6) the A1 wouldn't be able to deliver a well lit image, unless you got zero light. Are you using a light meter? The A1 doesn't have one so I'm not sure what you're talking about there.

Aperture tells you how wide the iris is open, measured by f-stop. Higher f-stop means the lense is more closed. If the iris is closed, then less light enters and you get a darker image.

Shutterspeed tells you how long an image is exposed. A lower shutter speed means that the image is exposed for a longer period of time which translate to more light and a brighter image. But with that exposure time comes increased motion blur. Most cameras defaulted to a 180 degree shutter which is a shutter speed that's doubled the framerate (1/48 for 24fps, or 1/60 for 30fps).
 
Nice explanation from Jade, I'll simplify it even more :

Aperture : Amount of light let in. Low number, more light and less "stuff in focus". High number, less light and more "stuff in focus".

Shutter : How fast the lens opens/closes. Higher number, more frames available (cleaner slow motion shots) but less light. Lower number, less frames available but more light.

Quick exposure :

1) If you don't care about slow motion or the like, drop the shutter to 1/60. High enough to not introduce blur. Adjust iris/aperture as appropriate.

2) If that's not enough, turn up the gain. I have mine set at Low = 3, Med = 6, High = 12. It's mostly on Med. Personal preference.

This is a very quick and crude method that doesn't take into account what your shooting but all you care about is "proper" exposure. Proper is in " " as proper exposure is all relative.

If you have any specific situation you'd like help with, post back. :) Hope this helps. I'd also recommend reading the book "Understanding Exposure". It's highly recommend for digital photography and I translated some of the techniques to my digital videography. Great book for ...umm...Understanding Exposure...heh.
 
To get good exposure, never trust the LCD. I suggest mapping the Zebra function to one of your custom key. Zebra tells you when a part of the image is overexposured and you can adjust it accordingly.
 
For camera basics, I really like this DVD (CameraCommand). I have gone back to it several times and get something new on each viewing. It is a fun DVD that is well produced. They are really nice guys too.
 
Sorry not light meter, I mean the bar in the upper left of the screen. Is that the exposure level? Is the idea to always match the level with the provided indicator? It was recommended to set it 1-2 settings higher than the indicator when filming in snow environments. Yet when I try to set the level higher than the indicator it always reverts back to match the indicator level automatically. What am I doing wrong?

WHen filming 24f, would I ever want to use a shutter other than 1/48? What about when filming high speed subjects (30mph +)?

How does the white balance affect the picture? Do I always want to set the white balance based off a solid white object whenever changing conditions outdoors?

I'm taking my A1 out in the field this tuesday for my first real world testing. GOing to be filming outdoors (no snow) in bright sunshine. I have the VIVIDRGB preset loaded. Going to be filming a guy snowmobile jumping. Plan to shoot alot of 24f and some 60 for slow mo. Wondering what settings you recommend and what I should play with to get a feel for the camera and get the best picture? Will definitely post back my results.
 
The exposure meter is mostly correct, it's trying to get an 18% Grey overall image. In snow conditions, you might want to overexpose a tad.

If you have the camera set in anything but "M" (Manual Mode) it will always revert back. In shutter mode (TV) you adjust shutter speed so it will do the aperture for you to bring the meter to the middle. In aperture mode (AV) you adjust aperture so it will do the shutter for you to bring the meter to the middle.

In manual, you do both to gain the desired exposure.

The other questions I'll leave to others. I don't shoot in 24f, only in 60i at all times.
 
Humanoid Typhoon said:
Nice explanation from Jade, I'll simplify it even more :

Shutter : How fast the lens opens/closes. Higher number, more frames available (cleaner slow motion shots) but less light. Lower number, less frames available but more light.

.
Click to expand...

Try not to simplify it too much! :) This is not really accurate, because the shutter speeds normally used will not change the frame rate at all. Only when the shutter time is set longer than the frame period will it make a difference, and this is more like a special effect than a normal shooting condition.
 
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