Why use M when you have A?

[NateWagner]

have you not read the rest of the thread?

We have already covered this. You can just dial in the exposure compensation the extra one spot. You can lock the exposure on the part of the scene you want composed and then recompose (again dialing in the exposure compensation if you wish).

The argument from the AV/TV side is that you can do all of the same things as in M just by dialing in Exposure compensation to change the automatic variable as long as you are doing so within about a +-2 stop range. Beyond that exposure compensation will not help and you would need to use M.

M is also helpful if you know the exact settings you want and don't want to change them, or have them at all different. Of course, you can just have your camera not meter if you so desire.

 

[dxqcanada]

Yes.

No, I did not read into this thread that using the Exposure Compensation option is the best method to manually control exposure.
From other poster's comments ... using full manual exposure control is advised.

 

[Derrel]

Outdoors in the spring time, with a jumping event like high jump, the photographer using Aperture Priority Aurtomatic picks an ISO setting, let's say ISO 800, so that he can get a wide aperture, let's say f/3.5, and a high shutter speed like 1/2000 second. F/3.5 with a 200 to 300mm lens will provide a limited depth of field, effectively blurring the background on each and every frame shot. The shutter speed will always be the fastest it can be, given the f/stop selected. If the sun peeks out from behind a cloud, the shutter speed might go up to 1/6000 second. If a dark rain cloud passes by the sun, the shutter speed might drop to 1/1200 second. In any and all cases, the background will be blurred by the pre-selected aperture. If the camera were in Time Value, the lens would yo-yo the aperture smaller whenever the sun peeks out, often greatly increasing the depth of field and bringing the background more into focus.

This is why if using AV the photographer has to select an Aperture he is happy with. If he isn't happy with it he can change it. I suppose your biggest argument here seems to be the DOF changing and not being stable. Of course the problem is you have to deal with it some way. If you don't change the settings you will have to deal with over/under exposed images.

Also, I have no idea what the "picking the ISO" has to do with anything. You have to pick the ISO if you're using M or AV or TV for that matter. How does that matter one way or the other to the topic at hand?

If you pick a Time that is very fast, let's say 1/2000 second, and your subject runs from the bright part of the course into the shade, your lens might not have a wide-enough maximum aperture; the system will decide to lower the shutter speed so far that blurred photos will result.

If you use TV the camera will always take the image at the shutter speed you select. Thus, what will happen is if you "run out of f/stop" the camera does not lower the shutter speed, the image is merely underexposed. If this happens this is operator error, and something that the photographer would have to deal with anyway.

Sorry Nate, but your reply indicates that we are not on the same page here. If you do not understand how the concept of the photographer "picking the ISO speed has anything to do" with shooting action photography, then my explanation went right over your head.

Nevermind.

 

[Overread]

actually on that second part with refrence to shutter priority mode you have lost me as well Derral. I say this because in shutter priority mode no matter what the lighting the shutter speed won't change unless the photographer changes it. The aperture will and the ISO as well if they have auto ISO enabled - but the shutter is directly under the photographers control.
Even if the camera runs out of aperture to open up it will still retain the shutter speed the photographer has dialed in to be used - underexposure or not.


This is unless there is some fancy exposure preservation feature which is present on some upper range camera bodies which is not present in the majority of lower and mid range camera bodies?

 

[Derrel]

The point of using an automatic exposure mode in action photography is to get a good,solid, fundamentally correct exposure, and not one that is four or five stops underexposed; that is what happens when one "runs out of f/stop". I was attempting to answer Nate's specific question about shooting action photos using Tv (as Canon calls it) or Shutter Priority automatic.

One of the goals in sports photography is to freeze action,and to focus the attention mostly on the action itself, and not on the background. I do not quite understand why Nate did not understand that the photographer will deliberately CHOOSE or select his ISO value...I mean, that is one of the very first things one does: continuous lighting exposure is a three-part equation: ISO value and Intensity (f/stop) x Time (shutter speed)....so, the first thing the photographer does is to evaluate the light level and select the proper ISO for the prevailing conditions: ISO 100 in the Texas Gulf Coast in August is fine at noon; at 5:45 PM in Seattle, Washington in March or April, the starting ISO will be from 1,000 to 2,400, given "real-world" equipment like a 70-200 f/2.8, or 300/2.8 lens; those who have 70-300 f/4~5.6 variable aperture lenses will themselves, choose or select the starting ISO at the beginning of the shooting session, and revise it as needed.

"Running out of f/stop" can easily happen with a variable aperture lens, like a 70-300 f/4~5.6 or other slow-ish lens. It can also happen, big-time, when the action moves from sunlight into shade, or in cloudy-bright conditions where the sun is playing peek-a-boo with rainclouds during much of the year. In Aperture Priority mode, with a little bit of an ISO cushion, an actual sports photographer realizes that he can "buy speed" by boosting his ISO setting up; in good,bright light or with a FF camera, there is almost no penalty to using ISO 800 or 1000, or now, ISO 3200; if the sun is out and the EV value is high, 3,200 looks good, with almost no noise whatsoever; if the action goes from full sunlight and into deep shade, there is still not much of a penalty at the elevated ISO settings, and since there is an ISO "cushion" that the photographer decided upon, based on the prevailing conditions, using Av mode, the photographer will ALWAYS get the fastest shutter speed possible AND a consistent depth of field when shooting in Av mode; this is not true in Tv mode.

The consistent depth of field one gets when in Av mode can be important because on the margins, DOF is sometimes pretty valuable as a safety factor on action that is hard to focus on; shooting wide-open at 300mm at f/2.8 gives almost no room for focusing error, but dialing the ISO higher, say from 200 to 800 on a good-light day, can give the photographer the option of setting and locking-in an aperture of say f/5; that will give a safety margin of focus to cover potential focusing errors. Even shifting from f/2.8 to f/3.5 with a 300mm lens is enought to give just a little bit of a safety margin for missed focus...the DOF safety margin gained by stopping down a bit is made possible by elevating the ISO a scant few clicks....and then moving the ISO another two or three third-stops to "buy shutter speed". The photographer needs to pick his ISO setting--it is a fundamental decision!

When using a long lens and when focusing is absolutely critical, the thing to do is elevate the ISO speed, pick a specific f/stop, and allow the camera to adjust the shutter speed from your absolute *minimum*, like say 1/1000, up to a higher speed, like say 1/5000. That way you will always get the right exposure and not an underexposure, you will get the DOF needed for both background control and any DOF safety margin needed to cover slight mis-focusing, and you will never suddenly find yourself in Tv mode looking at an LCD with a bunch of five-stop underexposed images...When one "runs out of f/stop" the result is underexposed images.

As stated, this type of situation is why AUTO ISO was invented.

 

[Overread]

Ok that makes sense - but you still don't explain how you end up with a lowering shutter speed whilst in shutter priority mode which you described earlier.

 

[florenceinitaly]

If you were in AV (or whatever it says on Nikon) and you had your camera set to f2.8 it would set the shutter speed to 1/500 you could then "spin the wheel" and under expose the shot by a stop, and the camera would change the shutter speed to 1/1000.

Thus the argument currently involved. Why set it to manual when setting it to AV will do the same thing for you, only faster.

Uhhh if it matters at all, this was the original part of my question, that either in A or M mode, i end up with (what seems to me) the same setting. So there must be some other advantage/flexibility that manual mode gives or we'd all be using A - this is what I'd like to know, if there's a pro that I had missed. Assuming constant ISO.

And in A, I meant controlling the aperture and exposure compensation (sorry I wasn't clear).

p.s. the OP is a "she", :lmao:

 

[Derrel]

Ok that makes sense - but you still don't explain how you end up with a lowering shutter speed whilst in shutter priority mode which you described earlier.

Well, what does one do in the situation I described???? Does one allow the exposure to drop two,or three,or four or five stops under-exposed, or does one shift the shutter speed slower to catch up to the f/stop???

"Running out of f/stop" means just that. I assumed that you'd correct the problem, rather than try to salvage badly underexposed images and just standing idly by. There's a light meter inside the finder.

There's a basic maxim in action shooting: pick an f/stop and pick an ISO to get the shutter speed you need. If one shoots with a variable maximum aperture lens,like so many people do today, what happens if one sets the "correct aperture" wide-open, at say f/3.5 at 1/500 second, and then zooms out so the lens drops to f/5.6. What happens?

 

[Overread]

Ahh the photographer changing down to a slower shutter speed (once aperture and ISO are taken to their acceptable limits as defined by the photographer) does make sense, but its not the same as saying that the system (ie the camera) will lower the shutter speed when in shutter priority mode; which is what you said earlier and which in turn lead to the confusion.

If you were in AV (or whatever it says on Nikon) and you had your camera set to f2.8 it would set the shutter speed to 1/500 you could then "spin the wheel" and under expose the shot by a stop, and the camera would change the shutter speed to 1/1000.

Thus the argument currently involved. Why set it to manual when setting it to AV will do the same thing for you, only faste

If you were in AV (or whatever it says on Nikon) and you had your camera set to f2.8 it would set the shutter speed to 1/500 you could then "spin the wheel" and under expose the shot by a stop, and the camera would change the shutter speed to 1/1000.

Thus the argument currently involved. Why set it to manual when setting it to AV will do the same thing for you, only faster.

Uhhh if it matters at all, this was the original partr.

Uhhh if it matters at all, this was the original part of my question, that either in A or M mode, i end up with (what seems to me) the same setting. So there must be some other advantage/flexibility that manual mode gives or we'd all be using A - this is what I'd like to know, if there's a pro that I had missed. Assuming constant ISO.

And in A, I meant controlling the aperture and exposure compensation (sorry I wasn't clear).

p.s. the OP is a "she", :lmao:

In the example there - where the desired settings are only a stop or so away from what hte camera meter is saying then yes, shooting in the semi auto modes (aperture or shutter priority) and using exposure compensation is very valid indeed. However there are times when it might be four, five or even more stops difference that you want to dial into the camera and in those cases the semi auto modes just can't give you enough leeway either side in order to give you those settings.

Thus manual mode comes to the rescue. In addition there are times when you want to take the same shot with exactly the same settings each time - to help avoid the cameras meter catching a reflection or altering a setting because the light is just at the boarderline between two values again manual mode gives the photographer that control.

In my own useage examples this is often when I have been using flash as the dominant light source - the room I'm shooting in might be very dark and the camera in teh semi auto modes will give me a very slow shutter speed - even though it knows the flash is attached. Thus one has to slip into manual mode and set the settings. This works because the flash fires a highly quick preflash when you press the shutter button (most people don't notice this preflash since it is very fast) - it then reads the light based on the settings from the camera and the light that bounces back to it and then adjust the flash power to give a proper exposure and then fires its main light.
This is why you have the separeate flash exposure compensation control - incase the flash gives a little too much or little lighting.

Of course one can also use all manual controls on the flash as well and things get a little more complex again

 

[mtfd635]

Though I usually A mode, the camera doesnot know what my intent is, so quite often I fall back to M.
But that's me, this camera, my typical subjects, etc etc

 

[NateWagner]

Sorry Nate, but your reply indicates that we are not on the same page here. If you do not understand how the concept of the photographer "picking the ISO speed has anything to do" with shooting action photography, then my explanation went right over your head.

Nevermind.

Derrel did you not read what I wrote? I said that picking the ISO is something that the photographer has to do regardless of whether or not he is using AV/TV or M. How does the photographers picking ISO matter when we are discussing AV/TV vs M? In this case picking the ISO is a controlled variable and does not matter for the case at hand of AV/TV vs M.

 

[NateWagner]

The point of using an automatic exposure mode in action photography is to get a good,solid, fundamentally correct exposure, and not one that is four or five stops underexposed; that is what happens when one "runs out of f/stop". I was attempting to answer Nate's specific question about shooting action photos using Tv (as Canon calls it) or Shutter Priority automatic.

I don't believe I asked that question.

I do not quite understand why Nate did not understand that the photographer will deliberately CHOOSE or select his ISO value...I mean, that is one of the very first things one does: continuous lighting exposure is a three-part equation: ISO value and Intensity (f/stop) x Time (shutter speed)....so, the first thing the photographer does is to evaluate the light level and select the proper ISO for the prevailing conditions:

I perfectly well understand this. That being said, if a photographer is shooting in AV or in M either way they will choose their ISO. If they are in some sort semi auto exposure mode it is still up to the photographer to choose the ISO.

ISO 100 in the Texas Gulf Coast in August is fine at noon; at 5:45 PM in Seattle, Washington in March or April, the starting ISO will be from 1,000 to 2,400, given "real-world" equipment like a 70-200 f/2.8, or 300/2.8 lens; those who have 70-300 f/4~5.6 variable aperture lenses will themselves, choose or select the starting ISO at the beginning of the shooting session, and revise it as needed.

ok...

"Running out of f/stop" can easily happen with a variable aperture lens, like a 70-300 f/4~5.6 or other slow-ish lens. It can also happen, big-time, when the action moves from sunlight into shade, or in cloudy-bright conditions where the sun is playing peek-a-boo with rainclouds during much of the year. In Aperture Priority mode, with a little bit of an ISO cushion, an actual sports photographer realizes that he can "buy speed" by boosting his ISO setting up; in good,bright light or with a FF camera, there is almost no penalty to using ISO 800 or 1000, or now, ISO 3200; if the sun is out and the EV value is high, 3,200 looks good, with almost no noise whatsoever; if the action goes from full sunlight and into deep shade, there is still not much of a penalty at the elevated ISO settings, and since there is an ISO "cushion" that the photographer decided upon, based on the prevailing conditions, using Av mode, the photographer will ALWAYS get the fastest shutter speed possible AND a consistent depth of field when shooting in Av mode; this is not true in Tv mode.

ahh, so your argument is that AV mode is better because in the DOF will stay consistent and you can just boost the ISO to get what you want?

The consistent depth of field one gets when in Av mode can be important because on the margins, DOF is sometimes pretty valuable as a safety factor on action that is hard to focus on; shooting wide-open at 300mm at f/2.8 gives almost no room for focusing error,

This of course depends on the distance from the subject to photographer to the subject. If you're at 300mm in the outfield fence it will be relatively easy to get the entire pitcher or runner in focus(actually from 100 feet you'll have a DOF of 5 feet and from 300 you'll have a DOF of 51.9 feet. This is quite a bit at the kind of distances you'll probably be using it.

but dialing the ISO higher, say from 200 to 800 on a good-light day, can give the photographer the option of setting and locking-in an aperture of say f/5; that will give a safety margin of focus to cover potential focusing errors. Even shifting from f/2.8 to f/3.5 with a 300mm lens is enought to give just a little bit of a safety margin for missed focus...the DOF safety margin gained by stopping down a bit is made possible by elevating the ISO a scant few clicks....and then moving the ISO another two or three third-stops to "buy shutter speed". The photographer needs to pick his ISO setting--it is a fundamental decision!

So basically your argument could have been summed up in about 1 paragraph rather than 3 pages worth inherently saying that actually AV would be better than TV when shooting action because it allows for a consistent DOF.

 

[Plato]

Or when what you want to meter on isn't dead center, where the 'spot' for spot metering is.

(I realize that some cameras attach the spot to the active focus point, but those cameras are in the minority.)

If you don't trust the meter, what do you trust? Is your eye calibrated to +/- a quarter stop?

Nope but my histogram is! And there are many times the meter can either be fooled or give the wrong results. Also the meter can't meter for dominant flash lighting - so any time where flash is the dominant light source the meter is reduced in its functionality. Which is why studio shooters and macro are often in manual mode - because the settings they set would register an underexposure given ambient lighting - but throw in flash and there is enough light for a proper exposure. (Which is why external meters are still used by studio shooters)

The histogram is fine when you have the luxury of repeating the shot. However, if you want the best result possible when you press the shutter button the first time, one of the automatic modes is your only viable option. I use aperture-priority most of the time and shutter-priority occasionally. I usually use auto-ISO.

Flash is an entirely different subject. Two meterings are involved, one for ambient lighting and one for flash. My D80 can be set to use either or both for a given shot.

As far as an external meter is concerned, my only reason for using one (years ago) was simply because they're typically more accurate than in-camera meters and obviously they're the only choice for measuring incident light. As with the histogram, the downside is the shutter lag (the lag before you push the shutter button).

 

[NateWagner]

Well, what does one do in the situation I described???? Does one allow the exposure to drop two,or three,or four or five stops under-exposed, or does one shift the shutter speed slower to catch up to the f/stop???

"Running out of f/stop" means just that. I assumed that you'd correct the problem, rather than try to salvage badly underexposed images and just standing idly by. There's a light meter inside the finder.

There's a basic maxim in action shooting: pick an f/stop and pick an ISO to get the shutter speed you need. If one shoots with a variable maximum aperture lens,like so many people do today, what happens if one sets the "correct aperture" wide-open, at say f/3.5 at 1/500 second, and then zooms out so the lens drops to f/5.6. What happens?

Can not the person using TV merely build in a "buffer" or whatever you called it into the shutter speed? Thus, they will be shooting with a higher ISO and at almost the lowest shutter speed that will guarantee frozen motion? Thus, while the DOF would change, during sunny parts they would be more up near the f/11-f/13 so long as in the darker parts it wouldn't stray below the f/5.

Either way, if they are paying attention to what the camera is choosing they should be able to make adjustments. If the TV shooter wants then bumping the ISO (if the shutter speed is set at a reasonable number) should boost the Aperture.

It's all about building buffers it seems, and you can do so with either AV/TV.

As to what happens, well, obviously either the shutter speed would slow down, or you would be underexposed. The problem there is that you have no buffer. Which you can easily build in, either boost the ISO, or lower the required shutter speed and you're fine.

It sounds here like the person shooting 3.5 at 500 has no buffer built in. If that is the case and they zoom in to 300mm then in AV they would have a blurry shot that is properly exposed, and in TV they would have a sharp shot that was a stop and a half under exposed. At least one of these would be possibly usable with work in post. Probably not the blurry one.

 

[jnm]

i think it's a matter of how you learned. Joe McNally lives in A, but he also has worked there for many many years and knows what EV to dial in to get the result he wants.