Auto Vs Manual control

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Tom Harper

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What’s the view on using full auto and only adjusting the exposure compensation? Is this as dumb as many would have us beleive?

Immediately I can see it limits creative possibilities when a slow shutter speed or small DoF is what your looking for but what is the difference between using AV or TV priority mode and adjusting the exposure compensation to suit your aims compared with using complete manual control. Would this not simply give a better chance of getting a correct exposure first time?

It often comes accross in many forums that using manual control is the holy grail of being an acomplished photographer but with todays technology doing much of the work with built in light meters is it really? Why not let the technology take the lead to get you in the ball park then just tweak the exposure compensation to suit?
 
Back when I had my Pentax Spotmatic everything was Manual. Nowadays I am more than happy to use Aperture or Shutter priority. I'll happily use any available technology in order to get the shot.
 
Hi Tom,

I think it's a case of knowing what you want and knowing what you are doing, even in AV and TV.
If you know WHY and HOW to alter the exposure/metering before you take the shot in AV/TV then you will probably have the same amount of control.
But if you take a shot and its too bright or dark then you have to alter and take another then its a lot slower in the end than manual.

On Saturday I was trying just that. I took a manual spot metered landscape and it came out perfectly.. with me spot metering from the grass and having that fall at about -2/3rds on the meter.

I then went into AV on matrix and took the same shot and it was overexposed and washed out. Id much rather get it right first time.
 
I use manual because I've always used manual - I personally think it gives me as much control as any of the Auto-modes.
Some - many, in fact - other photographers prefer shutter-priority or aperture-priority and use the EV compensation button to adjust and fine-tune the exposure. Both are equally valid as long as you know what you're doing, why you're doing it and get the results you're after...some also find it faster and more intuitive.

However, I still think it's better for beginners to shoot manual as it imparts a greater understanding of the relationship between shutter-speed and aperture settings (and ISO) than any of the auto modes.
 
For my macro work I shoot manual only, as I need to set things up for how I need them

My 'normal' more standard shots I use shutter priority 90% of the time, with some other manual adjustments like ISO etc etc
 
Was at a birthday bash recently with 100 or so close friends. We'd hired a pub out for the night. I was there, camera in hand fiddling with ISO and f-stop settings when one of my friends came over and asked what I was doing. I told him I was trying to work out what best worked in our surroundings. He just looked at me and asked how much my camera cost, I told him. "So stick it on auto, what exactly do you think you paid all that money for"?

I mostly shoot AV but have finally learnt there's nowt wrong with Auto in certain situations.
 
I very rarely use either full auto or full manual (although I do use both on occasion [compacts are usually on full auto and my rangefinders have NO auto anything!]). What I DO use is Programme mode. Sometimes I'll stick with whatever settings the camera decides on but more often, I'll tweak the wheel to get the shutter speed or aperture I want and it's very easy to dial in any over or under exposure you may want/need to get a specific effect.
 
I find whenever I use the AV or Tv modes my results are poor, if I'm usng Av and want a shallow dof, often the shutter speed is too slow and I get blury pics, if I switch to TV and want a faster shutter but lots of DOF it gives me a really wide aperture. If I use exposure comp I end up with high iso's and noisey images.

This is all made worse if I'm using flash too.

I find manual gets me the best results as I think humans are more intelligent than the processors in a camera!! we know what we want in our scene and how much light there is available :thumbs::thumbs:
 
joescrivens said:
if I'm usng Av and want a shallow dof, often the shutter speed is too slow and I get blury pics, :
Click to expand...

In this situation if you use manual and increase the shutter speed to avoid blurring does this not then result in an underexposed photo? Assuming of course that you don't change the ISO.

I might be missing something but if the inbuilt metering can't match a faster shutter speed to your chosen aperture I don't see how manually adjusting the shutter speed will make any difference without adjusting the ISO?
 
Tom Harper said:
In this situation if you use manual and increase the shutter speed to avoid blurring does this not then result in an underexposed photo? Assuming of course that you don't change the ISO.

I might be missing something but if the inbuilt metering can't match a faster shutter speed to your chosen aperture I don't see how manually adjusting the shutter speed will make any difference without adjusting the ISO?
Click to expand...

what I find is that the camera gets it wrong, like it will pick 1/20 for example when 1/60 or 1/80 would do. the tiny difference in shutter might be all thats needed to go from a pic thats blurry to one thats not.

Also a slightly underexposed raw that is sharp is much easier to deal with in PP, where I can shift the exposure up a tad than a well exposed but blurry shot .
 
I only ever use fully auto when I'm taking a photo for ebay and the SLR's the nearest thing to hand.

The rest of the time it varies between M, Tv, and Av depending on what I'm shooting and the conditions. ISO lives on manual too.
 
Tom Harper said:
In this situation if you use manual and increase the shutter speed to avoid blurring does this not then result in an underexposed photo? Assuming of course that you don't change the ISO.

I might be missing something but if the inbuilt metering can't match a faster shutter speed to your chosen aperture I don't see how manually adjusting the shutter speed will make any difference without adjusting the ISO?
Click to expand...

You also have aperture to change.

Given one constant, say for example you select the ISO and leave it at 100, then the other controls you have to use in order to get a correct exposure are the aperture and shutter speed.
In Manual mode, the combination of those two is selected by the user.
In Aperture priority, you manually select the aperture and the camera selects the appropriate shuuter-speed in order to acchive the correct exposure.
In shutter-priority, you manually select the shutter-speed and the camera selects the aperture.

If you change one thing after you've metered correctly for a scene, something else has to change to achieve a correct exposure, whether you do it manually yourself, or allow the camera's electronics to do it for you.

In Program mode, the camera selects both shutter speed and aperture.

Only if Auto-ISO is selected in the menu, will the camera adjust the ISO without user-input.
 
joescrivens said:
what I find is that the camera gets it wrong, like it will pick 1/20 for example when 1/60 or 1/80 would do. the tiny difference in shutter might be all thats needed to go from a pic thats blurry to one thats not.

Also a slightly underexposed raw that is sharp is much easier to deal with in PP, where I can shift the exposure up a tad than a well exposed but blurry shot .
Click to expand...

The camera is not getting it wrong - if you have chosen aperture and ISO all it can change to get a correctly exposed shot is the shutter speed, altering the iso will allow the camera to increase the shutter speed to get a correctly exposed shot.

Much easier to increase the ISO and get a correctly exposed image to start with - pulling underexposed images in PP introduce loads of noise into shadow area's.
 
joescrivens said:
what I find is that the camera gets it wrong, like it will pick 1/20 for example when 1/60 or 1/80 would do. the tiny difference in shutter might be all thats needed to go from a pic thats blurry to one thats not.

Also a slightly underexposed raw that is sharp is much easier to deal with in PP, where I can shift the exposure up a tad than a well exposed but blurry shot .
Click to expand...

If you adjusted the exposure compensation to underexpose the shot would this not have the same affect and let the camera then automatically selet a faster shutter? Assuming all other setting of ISO and AV are left the same. It seems its just two different way of achieveing the same result, increase shutter speed manually or decrease exposure manually? Or am I looking at this all wrong :bonk:
 
I'd possibly use Auto sometimes, if it weren't for the fact that it works only in JPEG mode!
 
Dogfish_magnet said:
The camera is not getting it wrong - if you have chosen aperture and ISO all it can change to get a correctly exposed shot is the shutter speed, altering the iso will allow the camera to increase the shutter speed to get a correctly exposed shot.

Much easier to increase the ISO and get a correctly exposed image to start with - pulling underexposed images in PP introduce loads of noise into shadow area's.
Click to expand...

what I mean when I say the camera gets it wrong, is for example lets say I let it choose ISO automatically, it will put a really high ISO when one quote a few stops down would have been more than acceptable.

So if I chose 2.8 as my Aperture and the scene was a little dark it might go for 1/160 shutter and 2500 ISO

where 1/100 and 1000 ISO would have been a better shot, with less noise and enough of a fast shutter speed so that the scene wasn't blurry
 
joescrivens said:
what I mean when I say the camera gets it wrong, is for example lets say I let it choose ISO automatically, it will put a really high ISO when one quote a few stops down would have been more than acceptable.

So if I chose 2.8 as my Aperture and the scene was a little dark it might go for 1/160 shutter and 2500 ISO

where 1/100 and 1000 ISO would have been a better shot, with less noise and enough of a fast shutter speed so that the scene wasn't blurry
Click to expand...

I thougt that the camera will always set the lowest ISO that gives the minimum shutter speed required for the attached lens to eliminate camera shake.
 
Tom Harper said:
If you adjusted the exposure compensation to underexpose the shot would this not have the same affect and let the camera then automatically selet a faster shutter? Assuming all other setting of ISO and AV are left the same. It seems its just two different way of achieveing the same result, increase shutter speed manually or decrease exposure manually? Or am I looking at this all wrong :bonk:
Click to expand...

With EV compensation, you're allowing the camera to override what it thinks is the correct exposure when using one of the auto-modes.
There's no point doing it for just one shot, but if you're shooting a sequence under the same light it saves you adding compensation each time.

Say the camera 'tells' you that correct exposure for a scene is 250th @ f/8 using 100ISO.
Using Shutter-priority, you select 500th sec as you want to freeze the movement of something. The camera will automaticall adjust the aperture setting to match what it thinks is correct.

However, when you look at the histogram on the back of the camera, you notice that it's still too bright for the scene you're shooting, maybe the sky is a bit blown or the white shirt of the subject is blown - whatever.
To overcome this you can dial in minus-EV to compensate and still keep the camera in Shutter-priority mode - the camera automatically changes the aperture to factor-in the compensation you want.

In aperture-priority, the camera alters the EV by changing the shutter-speed.

In manual mode you'd just be doing this yourself by looking at the initial exposure and adjusting either the shutter-speed or the aperture to where you want it to produce the effect you want, regardless of what the camera is suggesting should be the correcct exposure..
 
Dogfish_magnet said:
I thougt that the camera will always set the lowest ISO that gives the minimum shutter speed required for the attached lens to eliminate camera shake.
Click to expand...

The camera will not change the ISO unless you enable Auto-ISO in the menu.

But why would you? You might as well hand over all control to the camera and shoot in P or Green-Square mode...

And use all the auto P&P settings in Photoshop...
 
My wording was a bit backwards there.. on my my camera, if you put it in full auto, it will only output JPEGs - not RAWs. Neither do any of the 'creative' modes, apparently, however I think A-DEP, P, M, Av and Tv do. I only use M, Av and Tv.
 
I think you may have something set wrong on your camera in that case - it should shoot RAW in any mode you like...
 
Arkady said:
Eh? What?

I missed this one...care to elaborate on your thinking here?
Click to expand...

easy, a lot of cameras wont let you shoot jpeg if you are on auto mode. He's saying he would use it if he could get raw files from using it. My 450d was like this, if in auto it would only shoot jpeg, not raw
 
joescrivens said:
easy, a lot of cameras wont let you shoot jpeg if you are on auto mode. He's saying he would use it if he could get raw files from using it. My 450d was like this, if in auto it would only shoot jpeg, not raw
Click to expand...

:eek:

What a P-O-S camera...
 
Arkady said:
I think you may have something set wrong on your camera in that case - it should shoot RAW in any mode you like...
Click to expand...

Nothing is set wrong, it's just the way the camera behaves. Think about it, someone using full auto (green square mode) is probably doing so because they don't even know what a RAW image is. A 450D is an entry level camera so this is understandable.
 
My sony alpha shoots RAW in auto, not that i use auto though often anyway
 
It's one of the things that bugs me about mine, as well as all the 'creative' modes that I'd like to just erase from existance. Since I only ever use M, Av or Tv though it's irrelevant. If I wanted to use Auto I wouldn't have bought an SLR.
 
Arkady said:
The camera will not change the ISO unless you enable Auto-ISO in the menu.

But why would you? You might as well hand over all control to the camera and shoot in P or Green-Square mode...

And use all the auto P&P settings in Photoshop...
Click to expand...

I wouldn't but the Poster said -

' I let it choose ISO automatically'

i was just explaining how auto ISO works with AP and how it choses shutter speed with auto ISO enabled.
 
Dogfish_magnet said:
I thougt that the camera will always set the lowest ISO that gives the minimum shutter speed required for the attached lens to eliminate camera shake.
Click to expand...

ok, here is an example, not a great subject and all that but i think it might help with my reasoning.

on AV at 2.8 with ISO set to auto the camera picked a shutter of 1/125 and ISO of 3200

4514372334_2934c35532_o.jpg


100% crop
4514372916_a883ae8907_o.jpg


when I set it to manual, I picked ISO1000 as I didn't want as much noise, and I know I have a steadier hand than 1/125 so went for 1/50

4513732295_54b79331f8_o.jpg


100% crop
4514373240_fe8c46cdbe_o.jpg


so I think my judgement was better than the cameras because the camera doesn't know what noise level I considered to be acceptable and what I'm like with the hand held. Now If I took the camera off auto ISO at dialed in 1000 at 2.8 on AV it picks a shutter speed of 1/20 and thats too slow s I get blur:

4513752989_910da35575_o.jpg
 
It annoys me that in manual mode the AUTO ISO keeps it on 400 ISO all the time. :bang:

Why can't it change like when in the other modes?
 
joescrivens said:
lol, not exactly, its a pretty good camera. probably not the only one that does this, just the only one I know of as I used to own one
Click to expand...

That guy in your avatar is making me drool.
 
As a beginner I started by using aperture priority all the time but found that sometimes I was concentrating so much on other things that I forgot to adjust the shutter speed between shots when the light changed.

I've switched to using manual now and find that I concentrate more on getting the exposure correct because I know it's all down to me. I still use aperture and shutter priority occasionally when it's more convenient but stick to manual most of the time. It's definitely improved my pictures.
 
joescrivens said:
ok, here is an example, not a great subject and all that but i think it might help with my reasoning.

on AV at 2.8 with ISO set to auto the camera picked a shutter of 1/125 and ISO of 3200

4514372334_2934c35532_o.jpg


100% crop
4514372916_a883ae8907_o.jpg


when I set it to manual, I picked ISO1000 as I didn't want as much noise, and I know I have a steadier hand than 1/125 so went for 1/50

4513732295_54b79331f8_o.jpg


100% crop
4514373240_fe8c46cdbe_o.jpg


so I think my judgement was better than the cameras because the camera doesn't know what noise level I considered to be acceptable and what I'm like with the hand held. Now If I took the camera off auto ISO at dialed in 1000 at 2.8 on AV it picks a shutter speed of 1/20 and thats too slow s I get blur:

4513752989_910da35575_o.jpg
Click to expand...

It may be blurred but its correctly exposed :)

What lens did you use for that shot ? - theres loads of red & Green CA showing on the crops :eek:
 
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