Wide Aperture - Filter Advice.

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Rob
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Evening all :)

The thread title does not explain things very well I know, however my problem is; I'm after a little advice when it comes to using wider aperture outdoors on sunny says (if we ever get any sun anytime soon :bang:)

I just got myself a 85mm 1.2, I have the distinct feeling that if I attempt to use f/1.2 or around that mark outdoors on a sunny day portrait session, its going to easily max my shutter speed.

The only way I can think of keeping the shutter speed down is a. grab a poloriser - however I'm not sure that going to be strong enough, or b. grab a screw on ND filter - however I'm not sure what grade to go for....

Now I have no experience with ND filters - I was wondering if anyone else had gone down a similar route when in the same situation and could give me some advice?

Thanks in advance :)
 
Evening all :)

The thread title does not explain things very well I know, however my problem is; I'm after a little advice when it comes to using wider aperture outdoors on sunny says (if we ever get any sun anytime soon :bang:)

I just got myself a 85mm 1.2, I have the distinct feeling that if I attempt to use f/1.2 or around that mark outdoors on a sunny day portrait session, its going to easily max my shutter speed.

The only way I can think of keeping the shutter speed down is a. grab a poloriser - however I'm not sure that going to be strong enough, or b. grab a screw on ND filter - however I'm not sure what grade to go for....

Now I have no experience with ND filters - I was wondering if anyone else had gone down a similar route when in the same situation and could give me some advice?

Thanks in advance :)

I wouldn't worry too much, we won't see the Sun for a few months now :lol: Polarizer should take care of it, if not THEN think about good ND (Hoya and BW make good ones). You can easily work out the speed by taking any photo taken on a sunny day, and adjusting the stops (f/1.2 is 2.5 stops faster than f/2.8, so around 6-7x more light; CPL takes away about 1-2 stops, 40D can cope with 1/2-1 stop overexposure quite well). 40D can go up to 1/8000s which is plenty.

Edit: If you have any trouble I would happily take the lens off you.
 
You can work out what you need with help from the "Sunny 16" rule/guideline. When shooting in bright sunshine at f/16 you'll get a pretty good exposure when your shutter speed = 1/ISO. e.g. at 100 ISO your shutter speed will be 1/100.

Open up to f/11 and you'd need 1/200 at 100 ISO;
Open up to f/8 and you'd need 1/400 at 100 ISO;
Open up to f/5.6 and you'd need 1/800 at 100 ISO;
Open up to f/4 and you'd need 1/1600 at 100 ISO;
Open up to f/2.8 and you'd need 1/3200 at 100 ISO;
Open up to f/2 and you'd need 1/6400 at 100 ISO;
Open up to f/1.8 and you'd need 1/8000 at 100 ISO;
Open up to f/1.6 and you'd need 1/10000 at 100 ISO;
Open up to f/1.4 and you'd need 1/12500 at 100 ISO;
Open up to f/1.2 and you'd need 1/16000 at 100 ISO;

In other words, you should only need to lose 1 stop of light even in bright sunshine and a CPL will easily accomplish that. However, if shooting in a snow scene or over white sand or water you may find you need a little more because the extra reflectivity of those surfaces and surroundings will bounce more light back. In such instances you might need to lose 2 stops at the most. Twisted to the right position a CPL should take care of that too.

Of course, in anything less than bright sunshine you're not going to have a problem.
 
Thanks very much chaps, those figures help out a lot :) Looks like I wont end up with to much of a problem after all :) I'll opt for a polorizer and see how it fares!
 
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