Hi guys...actually what's ISO meant?Is it the higher the better?

Is this camera OLympus C350 good?? But ISO only limited to 400..many lastest nowadays got ISO until 3200..

Mind explain plz...?

ISO is the sensor sensitivity. The lower the better but need longer exposure time. ISO 3200 is bad, only marketing gimmick. Near useless unless ISO 3200 you talk about comes from nikon D300 and its higher siblings.

On a digital system, each image sensor has its base ISO ... some ISO100. some probably slightly higher like ISO125 or ISO200.

To increase the ISO means to increase the sensitivity to light above the base ISO value, hence the sensor is put in 'gain mode'. Due to this gain, it will introduce some noise to the image.

sometimes, its better to be able to take noisy photo than blur photo

the higher iso the noisier the pic (i.e more spots and grainy)

but now most compact cam got super high iso rite?

super high ISO most of them really just gimmick..

ability to caputure in low light condition with fast shuter speed to reduce blurry but by the end lot of grainy (noise).. BTW.. most of normal user feel ok rather than blurry image..

good camera tend to have auto noice reduction.. but it will soften the image.
but also still ok esp when u just

1. print 4r
2. resize to 640x 480 for you myspace picture

High ISO come with a price of noise. It might be a marketing gimmick.

So high iso are used for lowlight enviroment .. i.e night time?

Place : Dark Room
Item : Fan running @ Level 3

All shot with Flash
ISO @ 80
[attachmentid=396733]

ISO @ 100
[attachmentid=396734]

ISO @ 200
[attachmentid=396735]

ISO @ 400
[attachmentid=396736]

ISO @ 800
[attachmentid=396737]

ISO @ 1600
[attachmentid=396738]

ISO @ 3200
[attachmentid=396739]

Summary
@ low ISO, you could freeze the fast moving items, sacrificing the brightness details.
@ High ISO, you could get a brighter picture, sacrificing to freeze any fast moving details.

In other mean, Higher ISO absorb more light's detail while Lower ISO did't

Correct me if I'm wrong, been playing with ISO quite a bit and this is what my idea about ISO

iso3200 on canon eos30d.

Why your results are opposite ??

for the same exposure value (EV), aperture being constant,

High ISO should produce high shutter speed, thus able to freeze movements,
while Low ISO gives longer exposure time thus unable to capture moving objects.

and after all, to freeze an object should be under concern of Shutter Speed more, then only followed by ISO / aperture.

wrong wrong wrong.

ISO does not work alone. it works with other stuff like aperture and exposure time (shutter speed).

so let's assume we are going to take photos at Aperture f5.6

low ISO - longer exposure required. (shot taken with low ISO to achieve longer exposure time to achieve the effect)


higher ISO - shorter exposure required. (shot taken with higher ISO to allow shorter exposure time to capture the moment)

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Added on February 12, 2008, 8:59 am

hehe. the thing is this lor, can't just go based on ISO alone because the sensitivity works along with other stuff like aperture and exposure time.

These are the correct examples
Ya, ISO, exposure time, aperture.. these 3 things never work alone

That's why I confuse now.

From reading, Higher ISO will product high shutter speed

erm, ppl confuse with higher shutter speed sometimes.. like

1/100 (0.01 second), and 1/5 (0.2 second).

which is the higher shutter speed ?

the correct one is 1/100, becoz higher here means faster, not the value higher. The higher the value, the longer the time, the longer the exposure time,the slower the shutter speed,

I think I should start to use "longer" and "shorter" "exposure time" terms in futures

and maybe u can share the photos EXIF data for us to see what's your camera setting that produces those results.

which is why i'm using it. other terms commonly used would be FASTER / SLOWER shutter speed, which is less confusing than HIGHER / LOWER shutter speed.

This one I know lar

I'm confused why my digicam could freeze the movement of fan @ low ISO while higher ISO do the other way around

Then below this one is correct? It's a low light snapping without flash.

ISO @ 80
[attachmentid=396740]

ISO @ 800
[attachmentid=396743]

ISO @ 3200
[attachmentid=396744]

For this case, higher ISO reacts more sensitive to lights?

correct. when your aperture and exposure are constant, you'll see the effect like the above.

And if you have large aperture potrait prime, it is almost must have ISO100 or lower as the base. Why? At avaiable outdoor daylight + ISO100 @ f1.2, it easily hit 1/8000 (camera shutter limitation) already. And in a number of cases, over-exposure because my 40D highest shutter is only 1/8000. Base ISO of 50 would be ideal in this case...

If base ISO is 200, then I really dunno how to use liao...

Some say can use ND filter... But B+w ND is truly expensive... No point using Hoya that downgrade the quality...

lower your aperture la. it's not like you need f1.2 all the time.

the DOF would be crazily thin, no?

High ISO does not produce high shutter speed, it works together with shutterspeed and aperture to create exposure.

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Added on February 12, 2008, 10:21 am
For portrait, f2.8 already nice... no need f1.2 so thin, later the focus only on the tip of the nose or nipple only

i wonder why it were priced over rm6k for f1.2 lenses like the 50mm and 85mm. like u said, it have limited focus range span.

Some time it is good to have some active kid picture where all surrouding turn into dreamu blur.

I found 85L on my 40D still lacking some power into generating the extreme slim DoF I wanted. I guess have to go FF with 85L to further slim down the DoF.

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Added on February 12, 2008, 10:42 am
Simply put... because you had never tried it.

It is why most people cannot understand why people want to buy expensive and bulky SLR compare to a slim beauty like IXUS 860.

For long range application, should be fine because the longer the distance between subject and camera, the DOF will be wider, so you can benefit from the bright aperture.

If you shoot portrait close, DOF will be very thin, so big aperture is a bit useless.

Same applies to macro shots. Most macro shots come with f2.8 aperture, but we're most likely use smaller aperture like f8 or so.

Yap... That's right.

One of the problem with 85L on 40D (cropping factor camera) is that when shooting full body potrait with longer distance between subject and camera, the background is not creamy blur enought, not even at f1.2. It is why for those having this problem, might have to consider getting 1.3x 1D or FF. I am also considering FF because of this limitation...

While for macro shots, f2.8 is basically useless. It will use not less than f5.6, with usually at least f8. Thus it is why I always think the Canon EF70-200 f4 IS USM L is a great non-macro lense for macro usage. Must use with extension tube la.

u have a pretty much collection of lenses there. must be some bigshot.

though i have to agree that i havent tried the f1.2 lenses, but i've used the 50mm f1.4 before right before i sold it off. and to my likings, i still love the elcheapo f1.8 considering there's not much difference on my 30d body. plus saving some moolah for better equipment.

i donno, maybe it's just me, personally i think the f1.8 is a good enuff lens for portraiture.

when ISO and exposure cannot be helped already, what else can you do but lower the aperture. right?

remember, focal length is not only about 'zooming', it also can be used for framing.

shorter focal length = wider viewing angle
longer focal length = narrower viewing angle

that's why fixed focal length lenses still exist

ok i got it, been lurking for pics taken by f1.2 lenses, when the distance is further extended from the subject, the bokeh between the subject and the surroundings seems to be well-contrasted. wedding photographers should have love 'em f1.2 lenses. it gives the dreamy background to the subject and looks wonderful on their wedding portrait.

Well, what can I say... everyone need is different.

I had seen one uncle with only one Canon lense last time. EOS 1N + EF400 f2.8. This guy know what he want to shoot.

And years later, another guy in Penang with only 2 lenses; EF24-70 f2.8 L + EF600 f4


Find some where got shader to lower the light lo...

My avatar is shot at f1.2 but still very sharp even at 100% view.. Impossible to have handshake because shutter speed was between 1/2000 to 1/8000

Good example of high ISO images from a proper camera.
http://ishootshows.com/2008/02/06/nikon-d3...-iso-3200-6400/

CMOS geng geng...

I still remember few years back, lots of people simply said CMOS is rubbish and only for cheaper production...

canon 40d+iso3200+indoor =

How about ISO 9001

Sony alpha a350+ISO3200+indoor=

that ISO is under different category..
that's quality management.

We are talking about film light sensitivity..

^ Lol.

Canon, Sony... here's Nikon ISO3200 entry! Shot by me.

walauyeh, 14mp so good. Pawn all Canon camera liao like that.... then buy 40d for what?

The noise almost none existent even when printed 8R

But for shooting sports or if you use continuous burst most of the time, a 5fps camera is a must ... that's where the semi-pro bodies (D300, a700, 40D, E-3) are much more useful.