Dull conditions

[FUDGEY]

Right, I've been trying to learn what settings to use in dull conditions. Am I right in saying that I should lower my aperture low to f4 (lowest I can go on nikon d80) and increase ISO to about 400 from 200? Couple of questions, does this increase the shutter speed and what would happen if I turned the ISO up to lets say 1000? I guess this would give me a faster shutter speed, but I am guessing it will not be a good idea, I just don't know why. Can anyone enlighten me please?

[Lancashire Lad]

Short answer is - it all depends on what subject you are photographing.

If it's something which won't move, just use a longer exposure time.

If the subject will move, then you need to keep the shutter speed as fast as is appropriate for what you are trying to achieve.

The lowest aperture you can get on your camera will depend on the lens itself, and not the camera body. eg. I use a Nikon D80, with a Sigma f3.5 180mm macro lens, so when that lens is fitted, the max aperture that the camera will go to is f3.5. (I assume in your case, the lens you have on the camera must have a max. aperture of f4).

To give you an idea of the options with changing shutter speed, aperture and ISO speed, all of these will give the same equivalent exposure, but there will be differences in depth of field etc. : -

For example, lets say that you have your camera set at ISO200, and you have just metered a subject which is giving an exposure reading of 1/250th sec. at f11., so: -

So, if correct exposure = ISO200, 1/250th sec, f11
Equivalent exposure (1) = ISO200, 1/500th sec at f8 (but slightly less depth of field)
Equivalent exposure (2) = ISO200, 1/1000th sec at f5.6 (but even less depth of field)
Equivalent exposure (3) = ISO200, 1/2000th sec at f4 (but even less again depth of field)

Or, altenatively: - Correct exposure still = ISO200, 1/250th sec, f11
Equivalent exposure (4) = ISO200, 1/125th sec at f16 (but slightly more depth of field)
Equivalent exposure (5) = ISO200, 1/60th sec at f22 (but even more depth of field)

Or alternatively: - Correct exposure still = ISO200, 1/250th sec, f11
Equivalent exposure (6) = ISO400, 1/500th sec at f11 (with same depth of field)
Equivalent exposure (7) = ISO400, 1/1000th sec at f8 (with slightly less depth of field)
Equivalent exposure (8) = ISO400, 1/2000th sec at f5.6 (with even less depth of field)

Or even more: - Correct exposure still = ISO200, 1/250th sec, f11
Equivalent exposure (9) = ISO800, 1/1000th sec at f11 (with same depth of field)
Equivalent exposure (10) = ISO800, 1/2000th sec at f5.6 (with slightly less depth of field)
Equivalent exposure (11) = ISO800, 1/4000th sec at f4 (with even less depth of field)


The above are just a few of the possible alternatives (for the example exposure of ISO200, 1/250th, f11.), and the same principles would apply to whatever the correct exposure was.

The basic rules are: -
Widen the aperture by one stop (eg. from f5.6 to f4) - increase the shutter speed by one step (eg. from 1/60th to 1/125th)
Narrow the aperture by one stop (eg. from f8 to f11) - lower the shutter speed by one step (eg. from 1/1000th to 1/500th).
Double the ISO Speed (eg from ISO200 to ISO400) - then either narrow the aperture by one stop (eg. from f8 to f11) OR increase the shutter speed by one step (eg. from 1/60th to 1/125th)
Halve the ISO Speed (eg from ISO1600 to ISO800) - then either, widen the aperture by one stop (eg. from f5.6 to f4) OR lower the shutter speed by one step (eg. from 1/1000th to 1/500th).

As with all things though, there are trade-offs. Upping the ISO will eventually result in increasingly visible "noise" on the images, and in general, it is best to try to keep below ISO800. However, if you can't get the shot by any other means, then you will need to increase the ISO to 1600 or even 3200, and try to minimise the "noise" with post camera image processing in Photoshop etc.

Hope that makes sense.
Regards,
Mike.

[Tobyh]

Now that was a reply!! Where else can you get such detailed responses on all your favourite subjects!

TobyH

[FUDGEY]

Simple is you can't Toby, this is why I love this forum so much and it's members. Mike, ty so much for taking the time to write that mate, absoloutly brilliant bud. You are a star, thanks.

[Lancashire Lad]

Originally Posted by Lancashire Lad

....Or even more: - Correct exposure still = ISO200, 1/250th sec, f11
Equivalent exposure (9) = ISO800, 1/1000th sec at f11 (with same depth of field)
Equivalent exposure (10) = ISO800, 1/2000th sec at f5.6 (with slightly less depth of field)
Equivalent exposure (11) = ISO800, 1/4000th sec at f4 (with even less depth of field)......

Just realised I've left the wrong f numbers in equivalent exposures (10) & (11) - I was copying & pasting and forgot to change them

The correct versions are: -
Equivalent exposure (10) = ISO800, 1/2000th sec at f8 (with slightly less depth of field)
Equivalent exposure (11) = ISO800, 1/4000th sec at f5.6 (with even less depth of field)

Regards,
Mike.

[Geoff F]

I would just add, if your shutter speed drops too low use a tripod.

The traditional hand holdable shutter speed was advised to be equal to the lens length. For instance, 1/200 with a 200mm lens length or 1/400 with 400mm etc. But that is minimum speeds for a steady hand; faster speeds are usually better.

And, of course, modern stabilised lens (IS/OS etc) allow for slightly slower speeds.

[momji1971]

and remember that IS/tripods wont help where subject motion is a problem. Say birds in flight etc, you still need enough shutter speed to freeze the action.

regards.
Stu.

[PMG]

Originally Posted by momji1971

and remember that IS/tripods wont help where subject motion is a problem. Say birds in flight etc, you still need enough shutter speed to freeze the action.

regards.
Stu.

and remember to 'pan along' when birds are in flight - if you can - you stand more chance of stopping wing blur if you move the camera along with the action - like most things tho its hit and miss but always worth a burst of clicks to see if it works! I've never forgotten a hol in Norfolk a few years back and I was driving at about 25mph along a road when a barn owl joined us and flew parallel on hubbys side - he snapped off a few shots while me and the bird kept level and hey preston one was quite sharp consdiring the evening light and movement involved! Click first - ask questions later is my moto!!

Pauline

[Hobjob]

Originally Posted by momji1971

and remember that IS/tripods wont help where subject motion is a problem. Say birds in flight etc, you still need enough shutter speed to freeze the action.

regards.
Stu.

Using flash can also freeze the action, though with wildlife
this may not be possible because of distance.