I was curious as to setting the ISO in camera. If I set it higher for night shots or for speed,what is the difference between that and adjusting the ISO in Photoshop or Nikon View6. I notice I can increase the iso in those programs. Will the settings on the camera allow for the shot to come out properly, or will the grain just be increased and let more light in.

Setting the ISO in camera would be the preferred option because you will capture more detail in the scene if you do that. See article click here. You would not be able to recreate detail not captured in the first place by adjustments in PS or other software.

Attached Link: http://www.digicamhelp.com/advanced-digital-camera-settings/iso.htm

Doug,

Found this link that explains ISO a bit! From my understanding the higher the ISO the less light is needed BUT more noise can be introduced into the image under certain conditions. DSLR cams are better suited at it than the "PROSUMER" models like my Canon G6. If I goto higher than 200 ISO, the images becomes pretty useless! There are products like noise ninja that can "fix" noise, but again your (D70?) should have no problems with the higher settings! If your using RAW format...this may not be any issue. (I'm not that familiar with RAW!)

L8r!
Joe

Message edited on: 06/09/2005 11:49

Ahhh good links. Always interesting to read what others find.

In digital camera's, ith higher ISO settings there is more voltage set on the sensor. The higher the voltage, the more noise in your image, that's the downside. The upside is that you need less light to get the same result. If you're compensating the ISO in photoshop by increasing the light setting, you're missing details because they didn't get caught in the first place. dSLR's have less noise because they use bigger sensors which are less susceptable to electronic noise than the smaller ones found in compacts.

DSLR sensors are physically larger than the sensors used compact cameras, this is why they tend to be less prone to digital noise. I know that the D70 is pretty good up to 400ISO. Noise becomes more of a problem with long (very long) exposures of say 2 minuets or more. That said noise can at times add to an image if you are looking for a grainy type image. I have shot at 1600 and 3200 ISO with the 10D even at 3200 it is usable in some situations. I have got a 1600 ISO shot somewhere in my gallery, I will see if I can find it. To get back on topic a little I think that from 100-200 etc equates to the equivalent of 1 stop of light and so on. (I could stand corrected on that)

Shot at 1600 ISO, its not a great shot, as it was a 30 sec exposure and it was a bit windy, so it is alsoa bit soft. Of course the noise in more visible on the full size image, but for web use it would be acceptable if is was not for the cam shake.

Attached Link: ~ dream (!?) ~" target="_blank">~ dream (!?) ~

If you care to follow the link above you can see a night photo shot only with speedlite using 100 ISO and handheld.

I prefer higher ISO values for 'action shots'.

Carlos.

Carlos...how much do you mean 'higher ISO? I prefer more 'shutter' for action!

The whole topic of ISO in digital cameras is quite facinating the ISO rating is controlled through the image processing and it basically amplifies the charge caused by light hitting the photosites. In theory, when you expose a photosite to light, it should charge to the same level every time, as determined by the amount of light it receives. In practice, this does not happen; the pixel will not produce the same brightness every time, this produces one form of noise Read noise: Dark current noise is caused by a latent charge building up while the camera is turned on.. Current noise is increased as the sensor gets hotter.. Best when your camera is kept cool!! Canon also overcame some problems with the development of the CMOS sensor rather than the CCD in most other makes which had a better signal to noise ratio by in camera processing they only require 1% of the power and can manage respectable noise levels at even 3200 ISO As always for most of us it is a compromise always use as low as ISO as you can get away for the given subject matter to keep noise down in your images.. The other type of noise with ISO settings is caused by hot or stuck pixels. These occur when you use long exposures of more than 2 secs evident in images as patterns of red green or white dots

Also I guess, people assume more ISO with low light...also includes dull days too!..or is that a contradiction?

Jim,

I am afraid that is not a contradiction.
I choose the lowest ISO value possible even in very low light conditions

I use an IS lens and a tripod when necessary

Carlos.

ISO depends on the shutter speed you want to achieve at a certain F number IMO. So if you're shooting fast things (sports/birds/etc) and you want a fast shutterspeed you might end up upping your ISO setting because there may not be enough light for very fast shutterspeeds.

true...but the downside is....noise!...we know already there is less noise on DSLR's due to the sensor size...but theres always another day :)

Coming back to the original question: .....and adjusting the ISO in Photoshop Can you adjust the ISO in Potatoshop? where?...not stupid, just dumb!!!

Dont think u can Doug?

I change the ISO in camera, as I believe I get a better image, with less noise, than doing it when converting the RAW files. I increase the ISO when I need a higher shutter speed than I can get without changing the ISO. If I don't need a faster shutter speed there is no reason to increase the ISO. For example my Church photo taken at night, the camera was mounted on a tripod, and the church was not moving, so I used the lowest ISO I could. For this shot I used ISO 200 and the shutter speed was 25 or 30 seconds. I could have used a higher ISO and that would allow me to use a faster shutter speed to get the same exposure, but using the lower ISO produced a cleaner image.

As I do landscapes and buildings much like this mainly, shutter speed isnt too much of an issue, 99.9% shoot at 100 ISO, on a pod if need be. The only time this changes is if there are allot of trees in the shot, as they will blur badly with a long exposure (that can be cool sometimes) I have never had hot or stuck pixels on a long exposure and shoot up to 2 mins. Studio work no probs, just meter lights for 100 ISO (simplicity itself and sometimes a little boring) I have no idea how to change ISO in PS and IMO you probably cant change it in real terms after the fact. I guess the bottom line is, sometimes you have to compromise a clean image to get the shutter speed in some situations. Better to have a noisy image that to miss the opportunity, especially if you think you wont get a 2nd chance. Excellent and top class church shot BTW

Thanks Randy for posting a photo with an excellent explanation
It was one more honest 'help' and I agree with all you wrote

[ this thread was almost turning a dummy blablablashop ]

Carlos.

You've illustrated exactly my point Randy... ISO adjusted to shutterspeed and F number :) Since you didn't need high shutterspeed you could keep your ISO low.

...hmm. Back in the good old days the only way you could change ISO was by changing film. Now there's another knob to fiddle. Does anyone know: With a digital camera at the same Aperature, which will have the least noise: a) 2 Seconds @ ISO 200 b) 4 Seconds @ ISO 100 ?

@Misha883

My answer is a)

Carlos.

Misha - you posed an interesting question. I have not done any real world testing with my Canon 20D, but I will give you what I think based on shooting at different ISO and long exposures. With the Canon 20D there is almost no noise difference in ISO 100 and 200. So with your example I would say a) if you could tell any difference at all? I think both the ISO or time difference would have to be much broader to see difference. A shot with ISO 200 shot at 1/15th of a second and one shot at ISO 100 and 8 secs might start showing more of a difference. If you could see the shot of the church at original size you would notice very little noise and it was shot at 25 seconds and ISO 200. Of course digital camera's vary in their ability to shot night exposures. The Canon 20D is an excellent camera for low noise.

any time i've increased the ISO for night shooting it produced too much noise. i've tried using those noise reduction programs but they tend to "blob" even the parts with no noise. your best bet is to do longer exposures with the lowest ISO possible, that's what i do anyway... EB

[Thanks, ebsmooth. This is really a practical question! I tend to like long exposures (at a small f/stop) for film. Just wondering what is the best strategy for digital. Lengthing the exposure time, or increasing the ISO???] ...hmm ISO 200 @ 1/15th != ISO 100 @ 8 sec How 'bout (at the same aperature): d) 1/2 second @ ISO 800 b) 4 Sec @ ISO 100 ??

I prefer b) to d)

A lot depends on the type of sensor in the camera one strategy is not the same for another if its a CCD or CMOS sensor digital has less noise evident tahn film, when you blow up and image to A4 and above and it is just as true with digital that a lower iso gives finer grain/noise than high settings.. Very few sensors do a good job above 400 There may no longer be the same chemisty going on as I had with film trying to get the best balance is the key.. Perhaps another topic is the slower lens speeds these days I would like an f1.8 500mm lens please I am sure I would have less problems with noise and keep my ISO down to 200 then.. I always found I got less noise with longer exposures rather than putting up the ISO

Misha IMO b) 4 Seconds @ ISO 100 b) 4 Sec @ ISO 100 Because the ISO value has more impact that lenth of exposure. (unless its very long 30 sec or more) I have played with this a little, 800 ISO can be pretty noisy even with a fast shutter. Also noise shows up more in dark/uniform areas As Danob said it also depends on the type of sensor, and the CMOS seems to win out on this issue more than a CCD because of its lower power comsumption.

The aperture would not factor in the noise equation, except it will determine the length of the exposure. I agree with what others say, increasing the ISO will Introduce noise faster than increasing the exposure. I have gotten very good images with higher ISO with my Canon 20D, but as mention different cameras will have different results.

yeah Misha, i'd prefer the longer exposure with a small aperture setting. for some reason they just seem to come out better that way. everyone's always telling me a larger aperture but they just don't seem to be as detailed... maybe it's just me.... i wish my cam had an ISO lower then 200, though i never seem to have problems with it, i'd still like to go lower with a longer shutter speed... this shot was 30sec @ f/18 ISO 200. there's a little noise in the sky but not enough for me to think of it as ruined.. EB