Originally posted by Cavelle What is the AF/AE-L little button for?
What is the little button for, on the top right, with the green dot on it?
What should the little dial be set to on the left side - AF.S, C, or MF? What does all that mean?
This is a programmable button you can set to use for a rear autofocus (AF) control to focus on something before you decide to fire the shutter, or you can set it to its main use to lock exposure (Auto Exposure Lock or AE-L). These features might not be available when using the green "auto" mode where the camera does everything and you have no control- that is convenient but it is not infallible for all conditions.
Normally, you can autofocus on something before you release the shutter by using the shutter button half-press, but some photographers prefer a rear button for this purpose. As to AE-L, when using the Manual mode ("M" on the mode dial) you will set your own exposure by looking at the light meter readings and choosing your own aperture and shutter speed. But with other more commonly-used automatic exposure (AE) modes like "P" (Program) where the camera sets both your shutter speed and lens aperture according to the light meter reading, or "Av" where you choose the lens aperture and the camera sets the "correct" shutter speed, or "Tv" (Time value) where you choose the shutter speed and the camera sets the "correct" lens aperture- these are all Automatic Exposure modes (AE). So if you get a scene where the exposure is right on for your subject, but then move your camera to a different angle causing the background to change but you want the same exposure for your subject, you can hit the AE-L first before moving the camera which will lock that exposure before you move, so the very different background will not cause the camera's AE to react to that new condition and change how your subject turns out.
The green button is exclusive to Pentax. It is very convenient for a quick exposure setting when using the "M" mode, then you can make any change from there. If Using the "P" mode, the camera will be setting both shutter speed and aperture, but with Pentax cameras having a 2-dial thumb and finger system, you can override the camera's choice of either just by using those dials. This will instantly shift the mode to Av or Tv without your having to turn the mode dial first before making your choice. Then you can restore full "P" mode with a touch of the green button. This is the Pentax Hyper System- very fast and efficient.
MF means Manual Focus. Then you must focus the lens yourself by using the focusing collar on the lens. AF-S is what is most commonly used for autofocus (AF) single shot. The camera will only fire if focus is achieved. AF-C is continuous AF, where AF is continuously adjusting with movement of the subject or camera, and might fire even if focus is not achieved.
---------- Post added 10-09-20 at 12:53 AM ----------
Originally posted by Cavelle I like a lot of blur in the background as well... how would I achieve that without being right in the subjects face or close a particular object?
What you are looking for here is a relatively shallow depth of field (DOF).
To control DOF, the first aspect is the lens aperture you are using. The lens aperture opens wider (smaller number) to let in more light or less wide (larger number), making the opening narrower. Narrower provides greater DOF, making more of the picture sharp, but the reduction of light means a slower shutter speed must be used to let in more light to compensate. Opening the aperture wider to reduce DOF will result in a faster shutter speed to be used. This can blur the background to make your subject stand out more from it. The other factor affecting DOF is the focal length (FL) of the lens. A longer, more telephoto focal length will result in a reduced DOF even though using the same lens aperture. In other words, if you are taking a group shot and your lens is set at 18mm (shorter FL, wider field of view-FOV), and aperture set at say f/5.6, you will get a good picture, but your background will likely not be too blurred- in fact might be sharp, unless the background is at a good distance. At 18mm, your lens could open to f/3.5 for less DOF. However, if your lens is set at 55mm (a more telephoto FOV) for a portrait and your aperture is again at f/5.6 (which is as wide as this lens's aperture will go at 55mm), it is more likely that your background will be somewhat blurred, but less so if it is too close behind the subject.
There is a very good lens for portrait use at a modest cost. It is the Pentax DA 50mm f/1.8 prime lens (non-zoom). The focal length of 50mm is good for portraits, not having to be too close to the subject, and notice the small number aperture that is available with this lens- f/1.8 which is very wide aperture indeed. Far, far wider than f/5.6 as with your zoom lens. This also provides more aperture choices to blur your background more or less, and this is a high performing lens, for image quality, and to provide faster shutter speeds for either fast action or for hand-held low-light shots.
One thing to ask yourself- is your zoom lens 55mm setting ok for your shooting distance in portrait shots, but just the background blur being the problem? if you want to shoot from a much farther distance, you would need a lens with a longer telephoto reach, which would entail a higher cost.