Huge megapixels on a DSLR allows us to pluck a bird from the photo sky with amazing clarity; that is if all your other auto settings syncs with your endeavors such as a fast shutter speed to freeze the bird in flight.
However with all these wonderful auto functions on your DSLR, it creates havoc with the professional photographer as we fight to re-gain control of our camera.
In the old days, there were only four controls that we had to worry about and once you had selected the film with a fixed ISO, you are left with only three controls; focus, shutter speed and aperture.
With digital SLRs, you wrestle with a plethora of new controls ranging from white balance, Dynamic Range, saturation, noise reduction, auto iso and so much more. With everything set on Auto, you would think that you would get a perfect photo everytime, and it should, that is if we would just stop fiddling with the settings on the menu.
Like an airplane pilot performing flight check on all the dials, a photographer must run through all the settings before his assignment starts; testing with a few photos ensuring that the settings are performing as expected.
Auto-Focus
You really don't have much of a choice these days on focusing. Gone are the split prisms that aided the photographer in the old days. When an image converges in the focus area on a split prism, you know that you are in focus. However, with todays DSLR, manual focusing is more of a guessing game especially when you attempt to view your subject on the lcd panel in bright sunlight. Although there is usually a LED indicator, it is nothing more then the auto-focus at work, making you become the focus motor; so why not let the camera do all the work.
So it is a given that you have to use auto-focus.
Now the problem with auto-focus is "just what is it auto-focusing on?"
For most, it is usually the nearest object which means that it would be focused on the boquet of flowers in front of the bride, rather then on the face of the bride.
Even if you were to focus on the bride using selective area focusing, will the in-built camera predictive focusing compensate for the bride moving toward or away from you; ie will the bride still be in focus if she walks down the isle? or is your focus locked at her last position since you had your finger on the shutter.
If someone moves between you and the bride, momentarily, does your camera re-focuses on the new subject or will it track the bride before and after the interruption?
With the Nikon, continuous focusing will continually focus and track the bride as she saunters down the isle; focus tracking with lock-on will track the bride for 3 seconds (default) if someone dashes across the isle.
Combined this with an aperture of F11 giving you a deeper DOF, (depth of field) ,it should give you a fairly sharp photo of both her boquet and her face; regardless of whether your auto-focus focuses on the boquet or the bride's face.
If you don't have a firm understanding of how your auto-focus system works, even the most sharpest lens will not save your photos from a blurry grave. Getting to know your auto-focus and how it behaves is a very important aspect of todays cameras and will ensure that all your photos are as sharp as razors.
Auto-ISO
It is a wonderful feature, provided you use it correctly.
With Nikon, auto-iso, you can selected the minimum shutter speed such as 1/400 for soccer and with almost any setting including Manual, the camera will adjust your ISO for the light, matching your shutter and aperture selection.
This sounds like a wonderful auto feature, but it causes havoc with your studio lights. Since there are no pre-flashes with studio strobes, your camera thinks that there isn't enough light and therefore selects your highest iso to compensate. Thus with high ISO, your noise reduction algorithm will kick in, making all your photos just a bit blurry.
I shot a whole family photo session with auto-iso on, since I shot a soccer game the night before, and every photo ended up being shot at 6400 iso causing all the photos to be slightly soft due to the noise reduction that was applied.
Auto-iso also plays havoc with flashes. If the flash is not completely charged, the pre-flashes will tell the camera to bump the iso up since there isn't enough light. Your photo may end up being overexposed and again slightly blurry due to the noise reduction kicking in with the high iso.
Just remember to turn off auto-iso with flashes and studio strobes and turning it on when shooting in a variety of outdoor lighting situations.
Compensation with Auto-iso.
Compensation is used to overexpose a photo when the sun is behind the subject, or to underexpose a photo when too much light is being reflected causing the photo to be washed out. Compensation usually works with most auto settings by controlling your shutter or aperture speeds.
You would think that Manual mode is Manual (you have all the controls) and that compensation should only work with the other auto-modes. However Nikon and their think tank, says that if you decided to turn Auto-ISO on, then compensation will work even in manual mode by compensating with the ISO.
Thus if you have your settings in manual with a compensation of +2, auto-iso will bump up the ISO to overexpose your photo at your fixed shutter and aperture settings.
Definitely not what you would expect when shooting in manual.
Trusting your camera
Auto is a fallacy when you start to rely on it to compensate such as leaving it on Auto-iso to adjust to higher ISO for varying lighting conditions during an outside photo shoot. It is too easy to forget that you have left your aperture at F11 from an outside sunny day and suddenly shoot at 6400 iso indoors with a flash.
Some things are better set manually forcing you to go through the checklist everytime the environment changes rather then being surprised at the results after the wedding is done and gone.
Here are just some rule of thumb on using some of the auto modes.
- when using auto-iso, don't set the max iso to the highest iso of 25,000 unless you plan to under extreme lighting condition. Set it so that it peaks at an ISO that you would chosen under that kind of lighting condition, such as 800 ISO for an indoor shoot.
- choose wide area focusing for general event photography, but use the selective cursor focusing for portraits and position it exactly on the eye to get extremely sharp and detail photos (it is all in the eyes).
- auto WB is usually acceptable but a better method is to use the method described by Ken Rockwell on setting the WB.
Last words
In this day and age of Automatic settings, do a lot of test photos to see what the auto settings will choose for you; if it coincides with what you would have chosen then you are in luck as the camera thinks like you do; however if completely surprises you with its selection, like auto iso with studio lights, learn to take control of your settings. Don't let auto control you; be a professional and fight.
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