ISO100 vs ISO200 in DSLRs


Status
Not open for further replies.

rahul

Member
Jun 30, 2005
245
0
16
bendemeer
Hi

I am trying to ascertain the importance of having lower ISO values available for digital SLRs.

With low noise levels even at higher ISOs, how much of a difference would be there be, between ISO 100 and ISO 200.
Assuming that one is shooting a landscape on a perfectly bright day, would a picture taken at ISO100 show a visible improvement over the one shot with ISO200 ? Would this difference be visible in A4 size prints?

For an amateur who is trying to get the best quality at a budget, this would be an important issue to understand. Where one spends a "lot" of money on lenses, seeking better quality, it might be good to understand the importance of the grain/pixel.
 

If you're stuck out on a bright sunny day and you don't have a ND/ pol with you, low ISO's like 50 or 100 can help you achieve slow shutter speeds... Like when taking a shot of flowing water....
 

rahul said:
With low noise levels even at higher ISOs, how much of a difference would be there be, between ISO 100 and ISO 200.
Assuming that one is shooting a landscape on a perfectly bright day, would a picture taken at ISO100 show a visible improvement over the one shot with ISO200 ? Would this difference be visible in A4 size prints?

For an amateur who is trying to get the best quality at a budget, this would be an important issue to understand. Where one spends a "lot" of money on lenses, seeking better quality, it might be good to understand the importance of the grain/pixel.
Not significant, no difference, can't see. In the "old" days, especially for photojournalists, they wanted cheap and faster film at low cost. The ISO issue is way overblown, esp between ISO 100 and ISO 200 on any current DSLRs. Even with SD of around 4 (based on Phil Askey's testing methodology), printing to A4 is not an issue. In fact, the more important thing is the composition and you exposure, especially when "shooting a landscape on a perfectly bright day"

Too little noise or too smoothed images, in fact, can make an image look artificial. The image needs some texture in order to get a feeling of a real photo, rather than a digitally rendered image.
 

Firefox said:
If you're stuck out on a bright sunny day and you don't have a ND/ pol with you, low ISO's like 50 or 100 can help you achieve slow shutter speeds... Like when taking a shot of flowing water....
On a bright sunny day and you don't have a ND filter, the difference between ISO 100 and 200 does not matter when taking the "flowing water" shots. :rolleyes:
 

one stop of iso allows you one stop larger apperture for a given shutter speed. I'm a portrait photograher so this is useful because it allows a shallower DOF. Of course, this can also be acheived with ND filters... So, not much issue here.

From the imaging point of view, ISO 100 will certainly be less noisy than ISO 200 on the same given camera.
 

Watcher said:
On a bright sunny day and you don't have a ND filter, the difference between ISO 100 and 200 does not matter when taking the "flowing water" shots. :rolleyes:

ISO 200 to ISO 50 makes quite a fair bit of difference.. It can mean the difference between 1/60 & 1/15..
 

showtime said:
From the imaging point of view, ISO 100 will certainly be less noisy than ISO 200 on the same given camera.
Theoretically, yes, but practically? See here. Compare the amount of noise between ISO 100 and 200 on say, 1DsMkII :rolleyes: . To my eyes, the difference is about 0.1-0.15 SD
I can say that shooting at 25 degrees has less noise than 30 degrees celcius, but in practical sense, by how much? :rolleyes:
 

Firefox said:
ISO 200 to ISO 50 makes quite a fair bit of difference.. It can mean the difference between 1/60 & 1/15..
Nope, it doesn't.
 

Firefox said:
ISO 200 to ISO 50 makes quite a fair bit of difference.. It can mean the difference between 1/60 & 1/15..
Maybe, but firstly, the originator is comparing between ISO 100 and 200. Secondly, he is asking about noise/grain. For the silky smooth water, you need at least 1/2-3 secs. At the timing between 1/60 to 1/15, the image will not give the silky water that you are talking about.
 

Watcher said:
Maybe, but firstly, the originator is comparing between ISO 100 and 200. Secondly, he is asking about noise/grain. For the silky smooth water, you need at least 1/2-3 secs. At the timing between 1/60 to 1/15, the image will not give the silky water that you are talking about.

Yeah... Nevermind... That was just an analogy anyway... The same applies if that 2 stops of ISO will allow you to go down to 1/2s or 1s.. More of an issue to me if you want to remain at certain apertures (whether for the sweet spot or due to DoF)
 

There isnt much difference between ISO 100 & 200. If you shoot landscape,
use 100, and if you shoot the flower in the forest, use 200.
 

ISO 100 vs ISO 200 in DSLR at "normal" shooting conditions should not give significant difference in pic quality.

But by changing between the ISO +/- 1 stop or 2 gives you the control over DOF and "motion" via aperture and shutter.

mabbe waterfall example above is not appropriate... how about panning cars in those carpark races? Or in the case of aperture, getting more DOF in close up photography?

it more the "finer" details of photography where you want to capture exactly what you want.
 

the more choices you have, the better it is. That's why top end pro cameras like D2X and 1Ds Mk II offers a wide range of ISO from 100-3200 for the D2X and 50-3200 for the 1Ds Mk II.

For most people though, the difference between ISO 200 and ISO 100 in terms of noise and picture quality is pretty negligible.
 

Hi

Thanks for all you informative replies. Clarified the issue for me.
I was essentially looking at the quality differential between ISO 100 & 200.
I can see that it is almost negligible. The Dpreview side by side comparison was also very useful. Although it was a comparison between D2x and Mark II. I would expect totally top end performance from these two great cameras.

More humble cameras like D70 and 350D will probably display a little less level of noise suppression across ISO 100 & 200. Still it would easily pass a casual inspection and I dont plan on taking print larger than A4, unless someone else is paying for them :D
 

One problem I would like to ask when using ND filters is whether your AF may have some problems (ie it starts to get too dark to AF properly?

Been thinking of getting NDs for a while but haven't got around to it...mainly to slow the shutter enought to sync with off-shoe flashes.

showtime said:
one stop of iso allows you one stop larger apperture for a given shutter speed. I'm a portrait photograher so this is useful because it allows a shallower DOF. Of course, this can also be acheived with ND filters... So, not much issue here.

From the imaging point of view, ISO 100 will certainly be less noisy than ISO 200 on the same given camera.
 

Noise and quality is very much insignificant among all the makers from ISO100 to 400 today. However, the wider the options available to you, the more choices you have creatively.

Another note about using ND filters to achieve lower shutter speeds. Some ND filters are not truly neutral and might introduce a color cast in your images. It's your call on this issue. Some like the color cast, some are anal about it. Like everything in photography, it is a compromise. Get a camera with lower ISO, go ND filters, etc. You make the image, you decide how it's made.

Edit: Forgot another point. I used to experiment with closing the aperture to achieve slower shutter speeds. While it might work in a pinch, beware with going beyond f/11 with the cropped format digital cameras. Diffraction limits will start to affect your image quality by then.
 

Just a thought - Isn't ISO an outdated concept with digital sensors ? I mean its kind of a legacy concept from film photography.

In fact if you were to redsign the whole digital camera from scratch, aperture and shutter speed adjustments would still remain the basic functions, and the exposure compensation tool or an inbuilt digital filter could easily take care of scenes that are too bright (with the help of the camera filtering).

After all, unlike film, we don't expect digital sensors to introduce grain, and the practice of "choice of film speeds" and "pushing film" is irrelevant to the pure digital photographer.
 

i heard tat u can also use a polarizer as a ND filter as it remove abt 2 stops of light. haha jus my food for thought.
 

metalgear said:
Just a thought - Isn't ISO an outdated concept with digital sensors ? I mean its kind of a legacy concept from film photography.

In fact if you were to redsign the whole digital camera from scratch, aperture and shutter speed adjustments would still remain the basic functions, and the exposure compensation tool or an inbuilt digital filter could easily take care of scenes that are too bright (with the help of the camera filtering).

After all, unlike film, we don't expect digital sensors to introduce grain, and the practice of "choice of film speeds" and "pushing film" is irrelevant to the pure digital photographer.

For film, ISO means the size of grain. Bigger size means more sensitive to light but more visible grain. For digital, ISO was a rename from gain. The sensor receives same amount of light but was amplified and so is the noise. It can also be a result of sensor becoming too hot and misread the light. Basically you get "grains" for both but digital is more colorful.

Noise is different from one body to another so comparing Canon ISO 100 against Nikon ISO 200 is not valid. Or even comparing Nikon between 2 different models.

Film choice is still important. ISO is not only about exposure. Blur is also a consideration and higher ISO means lesser blur. Another use is flash photography. Higher ISO means your camera can still see all the way back even if you used flash.
 

Status
Not open for further replies.