Motorsport & ISOs?

[tomekay]

I know I am going to be lynched asking this question (still finding my feet really!).....but why is it recommended to use a higher ISO?

The sport mode on my 20d (I think) sets at ISO400. Is this the best ISO to use?

What are the general rules?

Cheers

[saturnin]

well that depends on the weather and what u want to get out of the photo

if its sunny why would u shoot iso 400? take it down to 100, if its cloudy or crappy weather where not much ligh is around gradualy bump your iso up till everything looks good, right.

all depends what type of photo you want also, are u panning to get motion or just shooting to get a clear shot, too many vairables.

my advice is to shoot on one of hte automatic modes and slowly learn what each function does. Thats how i htink lot of ppl started to learn that had no prior 35mm experience and jumped to dslr. Trial and error my man, trial and error.

[cosworth]

Wide open, 1/160th, polarizer.

I shoot at ISO,50, 100 etc...

[Simon Harrison]

Here's my approach to selecting the ISO I shoot at when photographing race cars or motorbikes on a 3/4 angle.

I'll choose the shutter speed I want to use depending on how much motion blur I want to show in the picture (usually between 1/250 and 1/320s, can be lower but seldom higher), and then I'll choose my ISO to give me enough depth of field to get the car sharp front to back, typically around f8.

Cheers,

Simon.

[saturnin]

my ****ing camera doesnt do iso 50, you SUCK..... were through, i cant keep listening to you keep boasting about your ****ing ISO 50, dont ever call me and oh one more thing, i want my ****ing THE WHO tshirt back.

[cosworth]

I turned it into a pillowcase.

[saturnin]

YOU MOTHER****ER.... i'm keeping mr.nibbles

[cosworth]

One of the great tragedies of the 21st century is that Sat's humour does not translate well to the internet, even though half his humour is because of the internet.

http://r.vanmullem.free.fr/gfx/Ricet%2520Barrier%2520-%2520Saturnin.jpg

Thread bastardized thoroughly.

[Strnge]

I shot in California sun, with no clouds with ISO 100. All weekend long at the Laguna Seca AMA Motorcycle races.

Tomekay..You should edit your profile to list where you live, so people close to you can help with similar problems or solutions.

Mike

[GSH]

I know I am going to be lynched asking this question (still finding my feet really!).....but why is it recommended to use a higher ISO?

The sport mode on my 20d (I think) sets at ISO400. Is this the best ISO to use?

What are the general rules?

Cheers

You should forget Sports mode for a start. As you say it defaults to ISO 400 in order to keep the shutter speed as high as possible. If it's a (rare in the UK ;) ) bright day, the shutter speed will go through the roof and you'll get frozen wheels on the car / bike. There are 1 or 2 strange people who like that but the majority think it looks awful, because it does.

Simon's post (above) is the clearest explanation you're likely to get. There's rarely any need to go above 1/400th for any sort of Motorsports shot.

[Steve Beck]

50 to me is not a great ISO for anything. I shoot between 100-200 mainly. But with the markIII I can now shoot indoor basketball much easier and better with iso 1600 and 3200 looking great. But to keep the images to the sharpness I stay between 100-200 unless I absolutley cant make it work in that range.

[John Thawley]

I know I am going to be lynched asking this question (still finding my feet really!).....but why is it recommended to use a higher ISO?

The sport mode on my 20d (I think) sets at ISO400. Is this the best ISO to use?

What are the general rules?

Cheers

First... and just to get off on the right foot with Cosworth... polarizers are for sissies. :D

The best advice here was stay out of "whatever" mode. You need to be in "mind" mode. Use YOUR head... the camera's mind can only think in generalities.

Here's the matrix you NEED to understand. Start with the formula the "X" = a correct exposure. So some combination of "S" (shutter) + "A" (aperture) = "X" based on the available light falling onto your subject.

Let's say it's a nice sunny day and at ISO 100 - 1/250th at f/11 gives us a perfect "X", if we bump to ISO 200, we could either increase the shutter speed (faster) or stop down the aperture to get the same "X" - except.. we'd introduce a little more grain.

Take your camera... put it on automatic. Shoot a scene where you get a correct exposure. Now... look at the settings the camera shot. Insert those same settings with the camera in Manual mode. Now shoot the same scene... and start adjusting the shutter up, the aperture down. The aperture down.. the shutter up. It's all a matter of letting in enough light to get the exposure (X) correct. A higher ISO is simply moving the entire scale up. It's a relative gain... effecting all settings equally.

If a correct exposure represented a full glass of water, think of how you'd fill the glass. Turn on the tap fast with a big gush of water and let it fill quickly. Or let the tap run slow with a thin stream and let if fill slowly. Either way, you'd get a full glass. Do you see the analogy.

The shutter/aperture combination are your sliding scales that equate to "X" - The ISO is a relative scale that effects the result globally over the shutter and aperture. If I like my shutter / aperture combination (creatively) and there's not a cloud in the sky.... I'm at 100 ISO. If I come back from lunch and it's now overcast... but still mid day, for the sake of this argument, I could just up my ISO to 200 and keep shooting at my original settings (this is strictly in theory) - a little later as the sun starts to go down, I could now move to 400 ISO... still keeping my same shutter/aperture settings.

Probably as clear as mud now... but that's hopefully a way for you to understand.

If you can find an inexpensive older analog incident meter, the dials can be the best teacher for educating you on getting control over your camera's decision making process. They used to make cardboard wheel charts that would also do the same thing. You'd set the ISO you're using, then select either the aperture or shutter... then the wheel chart would show you the other.

Ultimately, when you have control over those settings, you use them selectively and creatively to effectively compose your image to tell the story you're after.

Good luck.

JT

[Dave_G]

First... and just to get off on the right foot with Cosworth... polarizers are for sissies. :D




Hahaha

I'll second that

Polarisers basically block reflected light, so any shine the subject may have will be blocked out to a certain degree - your cars paintwork will look dull and dead.

Also many race cars have Lexan (plastic) windscreens (windshields), headlamp covers and side windows. The rainbow effect is not a good look.

Me? I subscribe to Simon's way of thinking. Shoot Shutter Priority at whatever shutter speed I want and choose an ISO setting to get the desired aperture value.

It's when the drivers switch their lights on that I switch to manual....

[ryant35]

This weekend I only changed my iso to 200 as it was getting dark to keep my shutter speed at 1/160 to 1/200

[tomekay]

Thanks guys for all your input :D

[cosworth]

Iso 50 gets used when you need it. Just because it's not optimal doesn't mean you should write it off.

There have been many times where I could have used ISO 25 or lower even. Tot motorsports per se, but just if the camera had it I'd have used it.

My polarizer is used to limit light, not depolarize it. I turn it just enough to see past windscreens and visors. Seeing "eyes" sells better than clouds.

Try shooting wide open @ 2.8 with a shutter around 1/160th on a hot sunny day and tell me what happens :)