Totally confused (As usual)

ash59uk

ash59uk

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Chris
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I find EC a little confusing.

Is EC the same as adjusting the white balance? if your subject is back lit, does using a negative setting adjust the sensor sensitivity telling it that the highlights are too bright and the opposite for a positive setting thus adjusting the dark and midtones when your subject is floodlit against a dark background?



I have read some of the other posts on here stating that it is just like increasing or decreasing the F stop but wouldn`t this have an effect on the total exposure rather than adjusting the bits that are too light or dark?

I just can`t get my head round this at all.
 
You are basicly overriding what the camera thinks the exposure should be, as a camera's meter isnt foolproof. If you are shooting a black dog against a bright sky, if you are metering the dog the camera will up the exposure to get the dog correct and blow the sky, if you meter the sky it will underexpose the dog. It cant figure out that you want a balance of both, so your apply EC to trick the camera into providing the correct exposure.

Thats a very basic way of looking at it.
 
ash59uk said:
I find EC a little confusing.

I have read some of the other posts on here stating that it is just like increasing or decreasing the F stop
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Nothing to do with fstop or white balance.. just as it says on the packet.. exposure compensation not wb or aperture :)
 
TCR4x4 said:
You are basicly overriding what the camera thinks the exposure should be, as a camera's meter isnt foolproof. If you are shooting a black dog against a bright sky, if you are metering the dog the camera will up the exposure to get the dog correct and blow the sky, if you meter the sky it will underexpose the dog. It cant figure out that you want a balance of both, so your apply EC to trick the camera into providing the correct exposure.

Thats a very basic way of looking at it.
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So if you use a negative ec you are telling the camera to lower the bright areas but not the dark?


What is a good rule of thumb when filming against a bright silvery sky?
 
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Exposure compensation does not selectively darken or lighten parts of the picture. It compensates across the whole picture.

A picture is made of of light. It is light falling on the sensor that produces images. To get the 'correct' exposure you have to balance how big the hole is (aperture) that lets in light and how long the hole is open for (shutter speed). You can do this manually on full manual mode. If you use full automatic the camera works it out itself. It does this using mathematical algorithms as it does not "see" what we see. Basically it measures light and works out averages to get an average grey. Any scene which has an excess of white or black (think like a black and white tv here) will 'fool' the camera as it will try to get this average grey. You needn't worry about that too much to be honest, just know that on full auto your camera can be fooled and expose wrongly.

One way around this is to use the semi-automatic modes - Aperture Priority and Shutter Priority. In these modes you choose one of the ways light gets in. If you choose Aperture Priority then you pick the Aperture. The camera will work out the shutter speed for what it thinks is the best exposure. Remember it can get it wrong! This is where exposure compensation comes in. Easiest way to get to grips with it at first is if you look at your rear screen and the picture looks a little dark then put some positive EC on. ALL IT DOES IS INCREASE THE SHUTTER SPEED. Nothing more fancy than that. Likewise in Shutter priority if the picture is too dark positive EC will open the aperture a little more.
 
Now the average grey bit. Well like I said you don't have to worry about it too much but if you want to understand when to use EC without relying on trial and error then you can try to get to grips with it. So, you have a beautiful blonde in a floaty white dress standing against a white wall. Your camera on full auto will assume average grey and expose the picture so. You will get a flat, dull, grey dress and wall. You could take the picture and see and dial in EC once you notice the picture is too dark. Or you could anticipate that with all the white going on the camera will try to make it grey. As grey is darker than white, you will need to let more light in. Positive EC.

Now you have a black dog running across a freshly plowed field. Too much dark colours going on. Your camera will try to get it grey. Black is darker than grey so you camera will expose for too long letting in too much light to lighten these dark colours. You need to dial in a little negative EC - tell the camera you need less light!

Sadly these changes affect the whole picture. Where you are going to become unstuck is where you have a really contrasty scene. Now your black dog is standing with the girl at the white wall. What you gonna do? There is no way to tell the camera where to give more or less light. As the dog is a small part of this picture (it's a cocker spaniel - she's 6ft tall) The camera will likely look at the entire scene and expose too dark, trying to make all that white average grey. So you will have dull girl, dull wall and a featureless dog to boot! You will still need to add more light, but you will likely still end up with a featureless dog. To get the light you need to show his features you will end up blowing the whites out and making them flat and featureless. Here you'd be best to try light the dog with a reflector - you need to add more light where you need it. Extreme differences in tones within a scene cannot really be handled well and that's where filters/HDR & Photoshop come in!
 
White Balance - a beginners guide. There is no flashy science here - you just need to know that light has a temperature. Well you knew that didn't you? After all the sun is really hot and so is a light bulb. The 'hotter' the light it the more white it burns. Think of car headlights some are really orangey and some quite yellowy. Some are blue. The blue ones are either blue painted bulbs (cheating) or they are genuine HID kits which are a type of lighting that burns at a very hot temperature.

White balance is just a way of telling your camera what kind of light you are in. Most are balanced for sunlight - and incidentally camera flashes are designed to burn at the same temperature as sunlight so those two settings are the same.

Old style traditional light bulbs have a low temperature and give of a very orange light. By selecting the incandescent mode on your camera all it does is apply a blue cast across the picture - this cancels out the orange giving a more 'natural' look. Exactly the same as putting a blue coloured filter in front of your camera (which is what happened in film days). The cast off the sun in the shade is a very blue light and again the shade function applies an orange filter to cancel out the blueness.

So White balance - nothing fancy just applies various shades of orange or yellow to your picture. Take a picture of the sea in full daylight but stick your camera on incandescent/tungsten mode. Will make the sea very blue!

Hope that lot all made some sense and made the complicated modes a little less so!
 
Vikki I would like to thank you for taking the time to explain EC and white balance so very well, I think the penny has finally dropped and I now have a better understanding of the subject.

I hope you don`t mind but I have copied and pasted the information you posted into a notepad doc for future reference.


Once again thank you for such excellent information and a few tips too!!

Oh I forgot to ask this.
On my camera with the histogram on screen I can move the histogram with a right and left button,What am I altering here?
 
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Ah, I need to look into that! Ive got a fujifilm in the cupboard. I'll rake it out and see what the l and r button does to the histogram.

I suspect that you just get to view different histograms and not ACTUALLY changing anything. Your main histogram will be the 'total' histogram for the whole picture then you can view just the reds in the picture, then just the blues and then just the greens. Gives a more accurate picture of the light distribution within the picture if you can separate out colours. TBH I rarely use it at this stage in my photography - I mainly use trail and error. But I imagine that people who are out taking shots for a living may do so as to get the correct image from the get go. I especially imagine it being useful for landscapes when you are doing long exposure shots. That can get very time consuming if you get it wrong and have to keep repeating as you would on a trial and error basis.
 
vixmix said:
Ah, I need to look into that! Ive got a fujifilm in the cupboard. I'll rake it out and see what the l and r button does to the histogram.

I suspect that you just get to view different histograms and not ACTUALLY changing anything. Your main histogram will be the 'total' histogram for the whole picture then you can view just the reds in the picture, then just the blues and then just the greens. Gives a more accurate picture of the light distribution within the picture if you can separate out colours. TBH I rarely use it at this stage in my photography - I mainly use trail and error. But I imagine that people who are out taking shots for a living may do so as to get the correct image from the get go. I especially imagine it being useful for landscapes when you are doing long exposure shots. That can get very time consuming if you get it wrong and have to keep repeating as you would on a trial and error basis.
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Using left and right does appears to lighten and darken the picture in the viewer it also shows clipping, now whether by tweaking it, it actually changes something I don`t know.

If I ever have had any time to myself (I have a disabled wife a 5yr old girl and 2 dogs) I could sit and have a really good mess about with the camera and probably figure it out myself. Again I could google the info but this forum doesn`t encourage that, at least until you have your 100 posts.
 
Great explanation Vikki
dave
 
ash59uk said:
Using left and right does appears to lighten and darken the picture in the viewer it also shows clipping, now whether by tweaking it, it actually changes something I don`t know.

If I ever have had any time to myself (I have a disabled wife a 5yr old girl and 2 dogs) I could sit and have a really good mess about with the camera and probably figure it out myself. Again I could google the info but this forum doesn`t encourage that, at least until you have your 100 posts.
Click to expand...

Well today I finally got a chance to have a good play with the camera, took the dog for his walk and took Kaitlyn along with the Fuji A330 I have given her to use ( I think She has got the bug too and She is only 5) Anyway I had a go pressing the right and left buttons (on the dial shaped switch)with the histogram on screen and it does actually adjust EC you can actually see the viewer lighten and darken the image, so I guess it is a shortcut to save having to enter the menu.

It is a nice little camera, today is the first decent day we have had for photography since I got it of ebay a couple of weeks ago.
If I could change one thing though, why doesn`t the damn thing only have auto iso in Auto? its a damn nuisance having to go into the menu when in ap or sp to continually change the iso to get the setting I want, it is hard enough only having a max aperture of F3.5
 
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