My question (I did a research and found no answer) I have my camera set up its been focused from far to near and now I'm doing my closing down my aperture to find the f-stop for this set-up, say it came out at f-16. Do you set the f-16 in the meter and meter, using it to be the f-stop to find the speed to set your lens to for this situation ...
W-on
How you arrive at a proper exposure depends on several factors. If f/16 is the important element then determine the aperture that gives you the proper exposure at f/16. How you do that depends on the type of meter you have. If you give us more information about the type of meter you are using we can be more specific.
Jerome
Not sure I follow exactly, but... first you set the film's ISO/ASA on the meter. Then, you read the scene. The meter should give you various combinations of f/stops and the corresponding shutter speeds.
I think I get what you're asking - shutter priority vs. aperture priority? Do you set the aperture and then meter for shutter speed, or do you select a shutter speed and then meter for aperture size?
You can do both at the same time. A lightmeter reading gives you a range of shutter speed/aperture size combinations, any one of which will "work". They all will give you the same exposure.
For example, if you set your lightmeter to use 400 ASA film, and take a light reading on a sunny day, the lightmeter may recommend an exposure setting of f/16 at 1/125th of a seconds. That suggested lightmeter reading is the same as an exposure setting of f/11 at 1/250th of a second, and the same as f/8 at 1/500th of a second, and the same as f/5.6 at 1/1000th of a second, etc. To calculate each of these aperture size/shutter speed combinations, you've simply doubled the aperture size and halved the shutter speed. You could also go the other way: double the shutter speed, and halve the aperture setting to get f/32 at 1/60th of a second. Any of the combination of these shutter speeds and aperture settings results in the same amount of light entering into the camera and will result in the same exposure.
Which particular combination you choose depends on several factors. Do you want a shallow depth of field? If yes, then select the shutter speed/aperture combo that has a large aperture size (like f/4). Do you want to have some motion blur in your photo? If so, then select the shutterspeed/aperture combo that has a slow shutter speed (lie 1/30th of a second) etc. If your scene is bright enough, you can have a fast shutter speed AND a small aperture. etc
I have the sekonic 558 for a meter if that helpsOriginally Posted by photographs42
W-on
The answers before this, although they tell you useful things, don't address the question you asked. I will try to do that here. The short answer is YES; after taking your meter readings, set the f-stop first in the meter and then determine the corresponding time .
But here is a longer answer which discusses the various factors involved.
If you use the near-far method and total focus spread to determine the f/stop, then, in principle, you need to use that aperture for adequate DOF. Hansma's method---the one described elsewhere at lfphoto.info---theoretically gives you the optimal stop balancing defocus and diffraction, so you should use that f-stop without modification. There is another simpler method---see below---which ignores diffraction, and that is meant to tell you the largest aperture (smallest f-number) that will yield adequate DOF, but stopping down more will just give you additional DOF and usually be acceptable. The f-stop which this method recommends is usually considerably wider that that which Hansma's method recommends. I've found that Hansma's method is often too conservative and that opening up a stop of two beyond what it suggests---using smaller f-numbers---is often acceptable. You have to decide on the basis of your experience whether you want to follow the recommendation for f-stop literally or to modify it according to the circumstances.
In any event, once you have decided on the f-stop, in principle you should stick to that and choose the exposure time so that you have proper exposure. Your meter will allow you to determine all combinations of f-stop and exposure times which will give proper exposure. You should use the one with the f-stop you've already chosen. In some circumstances, you may find that the indicated time is too slow and will lead to blurriness because subject movement due to wind or other factors. In that case, you may have to open up (use a smaller f-number) more than the method calls for to use a slower speed. In those cases you are choosing the best compromise under the circumstances. If you are using Hansma's method, as I noted above, it may be that you have some leeway to open up a stop or two without adversely affecting DOF and overall sharpness.
The simpler method. Determine the focus spread, multiply it by 10 and divide by two. That will give you the proper f-number. This works for 4 x 5 if you assume a coc of diameter 0.1 mm. Some people may want to use a smaller coc. The general rule is to divide the focus spread by twice the coc. This method is based just on defocus considerations and ignores diffraction.
As Leonard says, the simple answer is yes, however, forgive me if I’m wrong about this, your original question implies a lack of understanding of how light meters work.
The Sekonic L558 meter, if that’s what you have, is a very complex instrument. It has always seamed to me that it is more difficult to learn the basics of something like exposure using a complex digital instrument as opposed to a simple analog model. I’m not insinuating that your meter is a poor choice, only that it is harder to understand.
Your meter can function as an incident meter, reflected light meter, spot meter and flash meter. It also has the ability to store and average not only multiple readings, but also multiple types of readings I believe. All that makes my head hurt. Start with this premise. Any meter reads the light it “sees” in its field of view, averages it, and reports the combinations of aperture and shutter speed to use to make this average amount of light produce a negative that will print neutral (18%) gray. If your scene is in fact, average, you will have a full-scale negative that accurately depicts the scene you metered. Ah, if only life were so simple. Unfortunately, your meter has no clue if your scene is average or not. It also doesn’t know if the scene is low contrast, average contrast or high contrast. It also knows nothing about your film except the ISO setting provided by you. So you have to understand what it does so you can make allowances for the things it doesn’t know.
There are complete books written about this topic so I’m not going to even get started here, but you need to start with a single function mode of your meter and work with it until you understand what it is doing and what to do with the information if gives you. Then you can use that information intelligently to get what you want.
Jerome
Yes, that's what you do once you've decided on the f stop though in some situations you might go the other way and select the shutter speed first (e.g. foliage is blowing so you need a fast shutter speed or you want to blur moving water so you need a slow shutter speed, etc.) and use it to determine your f stop. But with LF landscape and other general purpose types of photography it's probably most often done the way you describe here, i.e. first determining the appropriate f stop then seeing what shutter speed is called for with that f stop. But the harder or more critical part is often the first part, i.e. picking the right f stop for the photograph you want to make. How did you arrive at f16 as the "right" f stop?
Brian Ellis
Before you criticize someone, walk a mile in their shoes. That way when you do criticize them you'll be
a mile away and you'll have their shoes.
Not only is the meter complex, but the L558 is VERY complex!
First check that your film speed is set correctly on the L558. Set the MODE of the 558 by holding the mode-button and spinning the jog dial until the 'sun icon' in the LCD display is circled by a box and "F" is circled by a box at the same time. That is your Apererture Priority mode. (You can set the meter's mode either before or after you meter the scene.) Meter your scene, using either incident or spot readings. Spin the jog dial until 16 is displayed. That is the camera setting for the light reading you just took at f/16... the meter will tell ou the associated shutter speed.
If you decide that Brian Ellis is correct and f/16 isn't the best aperture, just spin the jog dial again to display an aperture that you think is better. Again, the associated shutter speed will be displayed.
But like Jerome suggested, perhaps a more simple light meter (like a Luna-Pro) would better help you understand the relationships betwee the factors affecting exposure). The L558 is a GREAT meter but I heartily agree that it might not be best for learning the basics with. Good Luck to you!
I have a 508. Brian said what I was thinking. Much better in fact. It doesn't matter whether you are in shutter or aperture mode. I don't even look at the meter before I take a reading. Take a reading, spin the wheel till you see the value you want ( speed or aperature ) and read the other. Done deal. Bye the bye, mine is set up as Brian described.
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