effects of ISO settings

[albedo_0_39]

Hello folks, hope your all well!
years ago I vaguely remember seeing an article about the use of agfapan 25 asa (very slow) and fast films such as Ilfords Hp5 400asa. these films were spefically designed for building up images over a long period of time and capturing sharp images respectively. Now, I am interested in emulating the characteristics of these 'types' of films, or as close to these films as I can...so, can somehow help me, guide me to how to control iso settings with a digital camera. I have a Fujifilm S9500 and it's lowest setting is 80 ISO. I dont want to know specifically how to adjust the settings, I would like to know the effects of altering to 80 iso etc from the default (ie 200 iso) ?...so imagine I'm taking a shot of garden full of flowers with default settings and tehn want to take the shot again adjusting to 80 ISO. what's the effect likely to be?

thanks,
Gaz

 

[Jimmy_Lemon]

Longer shutter speed (unless its a bright day, or you lower the fstop) and less noise/grain. I think thats the only differences you will see. With a garden full of colour I doubt you would see any noise at 200 to be honest it only tends to show in the shadows. Dont know a lot about that specific camera, but I dont think changing to 80 will cause a vast difference

I would probably recomend setting up and trying a shot at 200 and 80, see what happens

 

[Inkblots]

I had the same problem when shooting,(but i use a canon 400d). I tried it out in different practises, this is a short list of how i found it..

iso 100 is a sunny day
iso 400 well lit stadium
iso 800 dark indoor
iso 1600 max strength pickup on the sensor. but it may look grainy not like iso 100 which can be pin sharp but dark.

I'm not sure this is right but its what i personaly found..

maybe ill be corrected..

 

[Gandhi]

The ISO setting on your camera is the same as ASA ratings on old film. So everything you remember, however vague, is still correct.

The lower the iso number the less sensitive the sensor effectively becomes, so if you kept the same aperture the shutter speed would increase to let more light in.

In your theoretical garden shot, if you dropped the ISO from 200 to 80 and kept the shutter and aperture settings the same, the shot would come out darker.


hth? I've perobably just repeated everything above, but 'meh'!