half stop inciments?

I've just been looking through the custom functions available in my camera and one of them is for half-stop or third-stop incriments. Is there any benefit from using half-stops apart from being quicker to go between full-stops?

light meters measure in 1/3 stops, your camera ISO is measured in 1/3 stops, probably easier for everyone involved to stick to 1/3 stops
 
I think it's just a carry-over from the 35mm cameras, my EOS 33v only does halves.
 
I set mine to 1/3rd stops, the main reason is for fine-tuning shots, especially when using flash so I can just creep through the exposure and make small changes. TBH though, in many cases, half-stops will be fine for most use, especially if the overall exposure is good to start with and only minimal PP is required....

I did read somewhere that half and third stops (in ISO) are 'fake' settings, with the camera actually using a clever bit of in-camera software to alter underexposer/overexposer in the shot when you're on settings like ISO 250 or 500 (etc)...... don't know how much mileage there is in this......
 
light meters measure in 1/3 stops, your camera ISO is measured in 1/3 stops, probably easier for everyone involved to stick to 1/3 stops

With the Sekonic L-358 I use you can set half or third-stops, and I guess this is available on many other meters

I did read somewhere that half and third stops (in ISO) are 'fake' settings, with the camera actually using a clever bit of in-camera software to alter underexposer/overexposer in the shot when you're on settings like ISO 250 or 500 (etc)...... don't know how much mileage there is in this......

I have also read this and belive it to be true on most cameras, I understand the Canon 1D series does give actual ISO setting yet all ther Canons work as you sugguest.
 
I actually like the idea and used to have it set at halves on my D90, i found it made it easier to learn about stops and how to use them.
 
light meters measure in 1/3 stops, your camera ISO is measured in 1/3 stops, probably easier for everyone involved to stick to 1/3 stops

Light meters measure light. They do not measure in 'stops' but simply calculate in an appropriate value to make the readings 'helpful' when applying the setting on a camera.
I had an old Sekonic meter that gave readings in 1/10th of a stop.

The camera's ISO, aperture and shutter values can be changed (on a lot of cameras) to either 1/3 1/2 or full values to suit the users requirements.
 
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I think it's just a carry-over from the 35mm cameras, my EOS 33v only does halves.

Not all 35mm cameras just meter in half stops, most of the autofocus pro and advanced level ones could also use 1/3rd stops. Plus there were/are some films such as Tri-X 320 and Portra 160 that were in 1/3rd stop speeds so it was useful for pro level cameras. The lattitude of film (especially negative film) does mean that 1/2 stops are usually all that are required though.
 
Not all 35mm cameras just meter in half stops, most of the autofocus pro and advanced level ones could also use 1/3rd stops. Plus there were/are some films such as Tri-X 320 and Portra 160 that were in 1/3rd stop speeds so it was useful for pro level cameras. The lattitude of film (especially negative film) does mean that 1/2 stops are usually all that are required though.

I believe most (if not all) 35mm film SLR's could adjust ISO in 1/3 stops, however, aperture & shutter speed values on some lesser models may only be available in 1/2 stops.
 
I believe most (if not all) 35mm film SLR's could adjust ISO in 1/3 stops, however, aperture & shutter speed values on some lesser models may only be available in 1/2 stops.

ISO has always been in 1/3rds on every SLR I've had, however the other scales are all over the place!

Pentax ME: Full stops only including EC
Pentas MX: Full stop speeds, with half stop indicated on the light meter. No EC.
Pentax Super A: Full stop manual speeds and EC, Half stops available for aperture setting in AE or Program
Pentax LX: Full stop manual speeds, 1/3rds on EC, fully stepless in Auto.

All the above have standard lenses which have full or 1/2 stop aperture rings

Olympus OM: Full stop speeds, OM2SP meausres in 1/3rd increments in manual and has 1/3rd increments for EC, as does the OM30.

Aperture ring (my ones at least) on Zuikos in full stop increments but max aperures often on half stops!

Pros tended to use Slide film, so needed the tight 1/3rd stop increments, whereas hapy snappers shooting colour print can get away with any old exposure value and still have a shot.
 
Not all 35mm cameras just meter in half stops

I was considering cameras at the same level from the same manufacturer, it says the OP uses a 30D so the 33v/30v were the equivalent 35mm EOS cameras.
 
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I've got my D700 set to use 1/3 stops and I find that it always sets 1/3 stops for shutter speed and on my 50mm 1.4G for aperture but on my 28mm 2.8D it only selects full aperture stops. Possibly because the lens has an aperture ring rather than having the aperture set electronically via the body like it does on a "G" lens.
 
boliston said:
I've got my D700 set to use 1/3 stops and I find that it always sets 1/3 stops for shutter speed and on my 50mm 1.4G for aperture but on my 28mm 2.8D it only selects full aperture stops. Possibly because the lens has an aperture ring rather than having the aperture set electronically via the body like it does on a "G" lens.

Wierd - can get my 50mm af-d to do third and half stop in the aperture when I set the aperture in-camera...
 
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Wierd - can get my 50mm af-d to do third and half stop in the aperture when I set the aperture in-camera...

Could be that I have got the camera set for aperture ring control instead of command dial control (for M & A modes), but I mainly use program mode so would have expected the aperture to be set in 1/3 stop increments. It does not matter as any fine adjustment would be done via the 1/3 stop shutter speed increments.
 
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