Sunny 16 vs Lenses sharpest F-stop (Portrait)

[AfternoonTea]

Next week I'm going on a photo-shoot on a sunny clear blue sky day, and I was wondering what rule I should lean on? I use a Canon 50mm Prime 1.4 lens, and I noticed that the sweet spots for sharp and blurry backgrounds is around F-stop 2.8 - 5.8. If I want to take a nice portrait with exposure on a clear sunny sky should I work with F-stop 5.8, and compensate the other values; Or should I abide with sunny 16 (even though F-16 is not the sharpest for my lens)? or would it even matter?

 

[samm]

How you know its gonna be a clear blue sunny sky .Id have a back up if its a dull dreary day, no sun, and over cast.

Them weather folk aren't always right .

 

[Derrel]

F/16 is a small aperture, and needs a slowish shutter speed; the speed of the shutter needs to match the ISO in use, so with the camera set to ISO 100, the aperture at f/16 for a sunny day, the shutter needs to be at 1/100 second. The problems are: 1-with a digital SLR, f/16 produces sensor dust spots on the picture unless the sensor is immaculately clean. 2) diffraction causes less-than-optimal sharpness 3)the slowish speed of 1/100 second creates the potential for blurring, or camera shake, or both, to occur 4)the deep depth of field often brings more emphasis to the background than is optimal for a portrait.

So, my suggestion: Shoot at f/5.6 at and speed up the shutter, to around 1/640 to 1/800 second or so, as a starting point. If the light is exceedingly bright, like a beach scene, or a snow scene, you will need to be more like at 1/1000 or 1/1250, or even 1/1600 second.

The f/5.6 aperture will give a nice, sharp image, with some degree of defocusing to the background, and the FAST shutter speed will stop subject movement, and allow you to capture expressions where the person is moving or laughing and so on.

 

[Tuffythepug]

Sunny 16, otherwise known as Basic Daylight Exposure, is a point of reference. Use whichever combination of shutter speed and aperture that is the equivalent for any given situation.
Having said that, the best thing to do is get a light meter and take the guesswork out of it. I got a good used spotmeter on ebay recently and it's been a valuable tool when using a medium format film camera that has no built-in meter.

 

[Light Guru]

If I want to take a nice portrait with exposure on a clear sunny sky should I work with F-stop 5.8, and compensate the other values; Or should I abide with sunny 16 (even though F-16 is not the sharpest for my lens)? or would it even matter?

Where does it say that if you use Sunny 16 you can only use f16? It is simply starting point for basing your exposure.

 

[AfternoonTea]

@ samm I'll put some trust into the weather man! He has been on a luck spree for the past week; If not I'll just wait till the day comes
@ Light Guru Well hence the 16 in Sunny 16 But I get what your saying; like Tuffy said its a point of reference.
@ Derrel Spot on what I was looking for! Thank you so much! I'll be sure to keep in mind the high shutter speed. [removed incorrect calculation]



I don't have a bunch of equipment as I do this as a hobby, and the photo-shoot is just for fun/practice. I'll most like bring some make-shift things (e.g. diffuse, reflector, gray card), and of course shoot in raw encase I goof up.

 

[Derrel]

Ummmm, no, you've got it wrong....the Sunny 16 Rule would be like this:

ALL AT ISO VALUE OF 100

f/value 16 at 1/100

11 at 1/200

8 at 1/400

5.6 at 1/800

4 at 1/1600

2.8 at 1/3200



So,the baseline setting for a sunny day at ISO 100 with f/5.6 is 1/800 second.

 

[AfternoonTea]

ahh I see, my calculation was way off! lol Thanks for the correction! Oh my! So much information gained today; I'm loving it! I'm going to take a few test shots to try it out, I'll post results later this week! But thanks again!

 

[Designer]

I suppose one could, in theory at least, actually take a meter reading before setting the ISO, the aperture, and the shutter speed.

Maybe that's too easy.

 

[TCampbell]

If the weather is anything other than cloudy, the Sunny 16 rule has you covered...

Increase the exposure by 1 stop for light shade. "Light shade" typically means you still see your shadow (it's just not as intense as it would be in full sun). If you cannot see your shadow, you're not in "light shade". High "thin" clouds would typically cause this type of lighting.

Increase by two stops for "medium" overcast. Medium usually means you can't see your shadow (or can barely detect it). But it doesn't look like it's about to storm.

Increase by three stops for "heavy" overcast or dense shade... "heavy" means it looks like it may be getting ready to storm.