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Focus on one thing / Expose from another - how to?
How does one expose on a certain part of a scene & focus on another? This is something I've struggled with in the past (mainly portraits at sunset). If I want to expose for those beautiful sunset colors, but focus on the model 5 feet in front of me, how is it done?
Thanks,
Bill
Thanks,
Bill
0
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What kind of camera do you have? Although it's not something I commonly do, I would be able to on my setup. But I have no idea about other cameras. If you let us know what you have, someone might be able to help out more.
Regards,
James
http://jziegler.smugmug.com
THere are a few ways to do this. I'll share my way. I'm sure others will do the same. It's up to you to know what works best for you.
Here goes:
NOTE:
This assumes your camera is set to full manual and you have a light source you can move around/adjust power (most likely a strobe)
- Set up your lighting so it is approximately where you want it. (you are not using this light yet, just setting it up for later)
- Set up your camera and compose your shot for the background (this has nothing to do w/ exposure, just getting all the elements in or out of the frame that you want)
- Adjust exposure for the background/sunset so the lighting is well balanced and looks how you want it to. (adjust using shutter speed first, then aperture *remember your max sync speed if your using a strobe)
- Bring model into frame and connect your off camera lighting so it fires when you shoot. Leave the camera on AF and lock onto your model.
- Take a test shot.
- Since your background is already properly exposed, all your doing is exposing for your model. So if the model is underexposed, bring your light closer (or increase power). If the model is overexposed, take the light sarther away (or decrease power).
Remember that the light is changing very fast at sunset, so don't get frustrated if this gets botched up on the first try. Just go another day and within a few frames, you'll have it down!This is just the outline of this shot. You can make it as simple or as complicated as you like.
Another thing to remember is that exposure and focus have nothing to do with each other. The only common bond they have is it's part of a larger package to make a picture.
The simpler way to do this is to use a Canon DSLR is Av mode with EOS flash - this will allow you to light the foreground with flash and the background exposure is set via the camera's choice of shutter speeds with - EC to darken the background the desired level. You may get a shutter speed that is long enough to require a triipod after dark.
I don't have access to young models, so I shot horse statues during the recent Horsin' Around in Terre Haute. I shot with a 550ex on a tripod, triggered with an ST-E2 on my camera, with exposure compensation of -1 for this kind of shot - This was shot in full sun at nine am...... I shot in Manual Mode because it gives you complete control over the foreground/background lighting ratio. You may (probably will) need to have your flash in High Speed Synch to allow this technique in bright sunlight. After sundown, it is much easier to do - particularly during twilight before it gets real dark.
And another horse shot at 11 am - Does this look like a sunlit morning street?
The Nikon system has similar abilities.
Moderator of the Technique Forum and Finishing School on Dgrin
:nono
Hate to do it, but this last part is incorrect info, at least on Canon's.
Remember, that depending on how the C.Fn are set, the metering is linked to the active focus point. (default Canon setting)
So, unless the default setting is changed or AEL is used, the focus point WILL have a large impact on the picture. (If using other than manual mode. Av, Tv, etc.)
Carry on...
Rwells is a funny man.
Carry on……
Canon 400D
Speedlight 580EX
Canon 70-200mm f4.0L
Canon 10-22mm f3.5-4.5
Canon 50mm f1.4
Hoya Cir-Polarizer
In the first part of my post I mentioned that everything would be set to manual. That's how I always shoot so the metering is not affected by my focal point.
Chances are most ppl arent' shooting full manual so I should have been more clear about that statement. Thanks for bring up that point! Now I know why that gun is still smoking
-Jon
This is what drives wedding shooters who don't shoot in Manual Mode crazy. Or adjust their custom functions to separate light metering points from AF points.
If you AF on a black tuxedo, or a white dress, the AF may be correct, but the exposure will be all over the map as long as the light metering is tied to the AF point.
Manual mode avoids this issue entirely, as long as you use a manual flash as well. As long as the light is stable, unchangeing, and the distance from the light source does not change, the exposure should not change.
Moderator of the Technique Forum and Finishing School on Dgrin
Hey Jon,
Definitely NOT trying to beat you up here, but even if shooting in camera manual mode, the focus point will still impact the exposure "if" a speedlight is used in ETTL II mode. (without AEL or C.Fn changes)
Even though in manual mode the meter is not changing any of your settings (App, shutter speed), it is still metering. ---- Remember where ETTL II gets it's flash duration info from, the camera meter/algorithm. In default mode, the meter is linked to the active focus point.
This is one of the many reasons I hear photogs say "I don't trust ETTL II", its inconsistant.
I just posted a pretty indepth explaination about ETTL II, here.
Oki Dohki
I totally agree! In my case though, the meter may as well be a doorstop. I never reference it since I'm almost always using strobes in manual. I'm developing the ability to set up and be within 1.5 stops of a spot on exposure though. It's pretty exciting knowing your gear like that.
The reason I don't use i-ttl is i have older speedlights (SB-24 x 5)that don't take ttl data and I use PW's that don't transmit ttl data anyway. I know a bunch about the big boy toys since I have friends that swear they take better pictures since the have better bodies and faster glass. I just can't justify buying better gear till my clients start paying for this stuff. I aslo don't cry when a speedlight hits the ground because a brolly acts like a wind sock. All my gear is expendable.
Good stuff. I definately learbned allot through your post!
If I still don't understand what your saying. PLEASE feel free to smack me about the head and neck and make it VERY simple for me!
I don't need to beat you about the head
I just want to make it clear to the original posters question. (Bill)
Bill will most likely be using a speedlight, not off camera lighting with pocket wizards.
So, he does need to understand the interaction of focus and exposure with that setup.
Bill, hope that some of all this helps you out. If not, please re-ask as we might have gotten a little off track to your initial question.
At least you got some entertainment from Randy shootin at the city kid w/ his six shooter!:D
Exposure with a strobe is a bit more complicated than normal exposure because in addition to apeture and shutter speed the exposure also includes the flash power. The easiest way to think about it is that there are actually two different exposures: ambient exposure deteremined by aperture and shutter speed; and flash exposure determined by aperture and flash power.
So then, in your example of a model and a sunset, the ambient exposure is chosen for the sky and the flash exposure is chosen for the model. Pathfinder mentioned the standard way to do this (at least with the Canon system) is to use manual mode on the camera; setting the aperture and shutter speed for the exposure you want for the sky. Then you use ETTL-2 metering to determine the flash power and hence the flash exposure. The key thing to realize here is that you are focusing on the model and using ETTL-2 to meter the model so the focus point and the in camera metering point are the same. The ambient metering is something you set up in advance potentially with the help of the in camera meter, but by using manual mode you are locking it in so at the time of the shot the camera only needs to judge the appropriate flash power.
Comments and constructive critique always welcome!
Elaine Heasley Photography
Much appreciated. I use a 20D & most of the time use an on-camera Sigma 500 DG Super (with Lightspere). I do have an off camera set-up (the basic Strobist package) that I use on occasion.
However, as stated above, yes, I'm looking to understand that interaction between exposure & focus & how to isolate the two.
Thanks!!
Bill
Bill,
LiquidAir posted a good recap a couple of post up.
The method he and PF posted works best.
Camera: manual mode - set exposure for your background
Flash: ETTL II
Now, simply compose the shot, focus on your subject and fire.
The manual settings will properly expose the background while the ETTL II flash (due to metering being linked to the active focus point) will expose your subject correctly.
As LiquidAir took special care to make stand out: the metering (for the flash in this case) being linked to the active focus point is the key to understanding this.
Now, go out and give it a try. Your gonna' like what you see
You guys are a big help. I'll be testing it this evening. Thanks...