grain/noise/dust problem!!!

[danalec99]

ISO, shutter speed, and aperture have a three-way relationship with each other. When one changes, one of the other two must change also.

You might want to check out the book Understanding Exposure.

Yes Mark, I need to get hold of it.

I'm confused with ISO and shutter speed now!!!

The reason why I said that is because while I was changing the ISO I thought it accidentally changed the shutter speed as well. I was desperate then . I now see the difference. But I need to get that book in order to go deep in to it.

 

[danalec99]

However, I would like to have a rough idea of this:

Okay, for the following settings when do we use a higher or lower ISO?

1. Outdoor - day
2. Outdoor - low light
3. Action/motion/panning shots
4. Portraits

 

[markc]

You usually want to use as low of an ISO as possible in order to keep the quality up. You use a higher ISO in low-light situations when you can't get the aperture/shutter-speed combo you want.

 

[danalec99]

You usually want to use as low of an ISO as possible in order to keep the quality up. You use a higher ISO in low-light situations when you can't get the aperture/shutter-speed combo you want.

Thanks Mark, and I have already placed the order for Understanding Exposure!!

 

[oriecat]

Wow, you are highly suggestible, aren't you? I think you should buy a print from Mark too, for all his help.

 

[danalec99]

Wow, you are highly suggestible, aren't you? I think you should buy a print from Mark too, for all his help.

suggestible? :?

 

[oriecat]

suggestible - easily influenced by suggestion

Sorry man, just a joke! He said to check out the book, and within 30 minutes you had not only checked it out, but bought it... I just thought it was funny. No offense meant!

 

[mrsid99]

Okay, for the following settings when do we use a higher or lower ISO?

1. Outdoor - day
2. Outdoor - low light
3. Action/motion/panning shots
4. Portraits

Mark is absolutely right in that ISO, shutter speed and aperture are completely inter-related.
High ISO number means higher sensitivity but more noise.
Higher aperture number (smaller hole) gives greater depth of field (DOF) but means less light enters so lower sensitivity.
Higher shutter speed ( shutter open for less time) means less movement occurs when the shutter is open thereby minimizing hand shake and good for "stopping motion" but again, less light enters so lower sensitivity.
So, for best quality you go for low ISO, for maximum DOF you want the highest F # (smallest aperture) and to minimize movement blur you need the fastest shutter speed.
This all adds up to the lowest sensitivity so you compromise.
Simplistic answers to your four conditions would be as follows:
1) Outdoor-day: Lots of light available so you can have a low ISO, a small aperture and probably still have a reasonably fast shutter speed.
2) Outdoor-low light: Not so easy this one, depends on what you want to shoot and how low is low light. If it's something stationary (landscape for instance) then keep a low ISO for best quality, depending on how much DOF you're looking for, say let's compromise with a midrange F # of 8. This is going to mean a longer exposure so a tripod would be called for.
3) If it's something moving then you would need a higher ISO, the lowest F # your lens will allow and the fastest shutter speed that works for those two conditions.
4) Portraits: Another weasel answer again in that it depends! If you're setting up in a studio you'll probably use a tripod, have lots of light and a reasonably fast lens and enough DOF for the subjects face so a fast shutter speed will minimise movement but if it's outside in low light then see above.
HTH and experiment for yourself.

 

[danalec99]

suggestible - easily influenced by suggestion

Sorry man, just a joke! He said to check out the book, and within 30 minutes you had not only checked it out, but bought it... I just thought it was funny. No offense meant!

No, I'm very much a newbie in this field, I do not need 10 hours to think when pros points out new stuff.

And no offence taken

 

[danalec99]

1) Outdoor-day: Lots of light available so you can have a low ISO, a small aperture and probably still have a reasonably fast shutter speed.
2) Outdoor-low light: Not so easy this one, depends on what you want to shoot and how low is low light. If it's something stationary (landscape for instance) then keep a low ISO for best quality, depending on how much DOF you're looking for, say let's compromise with a midrange F # of 8. This is going to mean a longer exposure so a tripod would be called for.
3) If it's something moving then you would need a higher ISO, the lowest F # your lens will allow and the fastest shutter speed that works for those two conditions.
4) Portraits: Another weasel answer again in that it depends! If you're setting up in a studio you'll probably use a tripod, have lots of light and a reasonably fast lens and enough DOF for the subjects face so a fast shutter speed will minimise movement but if it's outside in low light then see above.
HTH and experiment for yourself.

Thank you. That was a breather!

 

[mrsid99]

Thank you. That was a breather!

You're very welcome!
I'm glad I could help but that's what this forum is all about and there's been an awful lot of help given to me by many forum members and I'm learning more everyday.
Get that camera clickin'!!

 

[drlynn]

I would always use the lowest ISO setting that I could. As Sid said, when you're handholding in low light, you may have to bump it up.

For the situations you outlined, ISO 100 should be fine, depending on the desired dof, etc.


/edited for stupidity!

 

[ksmattfish]

What film are you using?

I use a 10D. This noise was not there until a few days ago!!

Ahh, your initial post said "grain" so I thought film...

I'm no digital expert, but it looks like noise caused by underexposure to me.

 

[danalec99]

What film are you using?

I use a 10D. This noise was not there until a few days ago!!

Ahh, your initial post said "grain" so I thought film...

I'm no digital expert, but it looks like noise caused by underexposure to me.

Pardon my ignorance. By grain I meant cacophony .

It is fixed now. The ISO was set at 1600 which caused the noise, thereby leading to the initial phases of a nervous breakdown

 

[photobug]

Does the 10D have a setting that automagically changes the ISP setting? It would be a custom function inthe menu probably.

If you haven't done any low-light stuff before this option (if it exists) may be enabled.

My *istD has this option, which I promptly killed. Ok, I only turned it off, but I'd kill it if I could.