Is there such thing as 'too low' an ISO?

[Trackslide]

Howdy all

I still consider myself a noob as I've only been doing motorsports photography about 9 months, a question has been bothering me for a while, but I keep forgetting to ask, so here it is lol

On a standard trackdays shoot, I tend to vary between ISO100 and 400 depending on the light, but do I need to?
If my camera settings are capable of shooting in Tv with the shutter im using without maxing out the aperture, do I have to bump up the ISO?
I usually move upto 200 for cloudy weather and 400 when it's getting abit darker, but if I stay at iso100 when it's cloudy, am I loosing detail?


Camera gear is mostly my 550d + EF70-200mm F4L

Thanks
Ste

[gjl711]

The difference between ISO100 and ISO400 is so negligible that I would not worry. Set the ISO to whatever you need to get the shot. Low ISO, longer shutter speed if you want some motion blur. Higher ISO, short shutter speed if you want to freeze motion.

[sandpiper]

Originally Posted by Trackslide

On a standard trackdays shoot, I tend to vary between ISO100 and 400 depending on the light, but do I need to?
If my camera settings are capable of shooting in Tv with the shutter im using without maxing out the aperture, do I have to bump up the ISO?
I usually move upto 200 for cloudy weather and 400 when it's getting abit darker, but if I stay at iso100 when it's cloudy, am I loosing detail?

No, you aren't losing detail by shooting at ISO 100. What you may lose, if there isn't enough light, is the ability to use a fast enough shutter speed to avoid camera shake and / or motion blur in the subject, and also the ability to stop down the aperture for more depth of field.

The way you asked the question suggests that you feel you should be shooting at the higher ISOs for quality. The rule of thumb has always been to shoot at the lowest ISO you can that gives you the aperture you want for depth of field and a fast enough shutter speed. You normally only raise ISO when you need to do so, in order to obtain the settings you want with aperture and shutter speed.

[Trackslide]

Ok cool
Cheers guys
I normally use the lowest ISO I can but when I was first learning to use a camera I was told to change the iso depending on weather.
Was only unsure of whether I'd be losing quality is all, aperture wise, I only mainly side pan so the shallow DOF usually goes in my favour with a wider aperture,
I've just learnt how to use a historgram correctly so I can shoot In manual as Tv with various metering modes let me down last weekend.

Cheers again

[Phil_mann]

Stu i'm normally using the lowest ISO possible and even that is too bright for the shutter speeds im using. The only time i usually change the ISO is if i go indoors.

[Tessa]

I shoot racing in very varied conditions (in late fall/winter we have only a few hours of daylight), so my ISO is all over the place. I always use the lowest ISO possible to get the shutter speeds I need, but if I have to go higher, I will do so without hesitation.

[Dennis Valet]

Once I set my shutter speed, I typically set my ISO to allow me to have the aperture in the 8-10 range

[troutfisher]

I'm getting more into motorsport and panning shots and I find typically 1/125-160,f8(ish) ISO 100 usually works to get wheel blur ( and frequently motion blur-but that's invariably my fault!)

[philwillmedia]

Is there such thing as 'too low' an ISO?
Yep.
It's when you can't get a fast enough shutter speed to get the shot you want when you're using the maximum aperture of the lens you're using.

[13inches]

I am a firm believer that you will never get a good shot at 0 ISO. That, in my opinion, is too low an ISO.