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I don't have a K-70 in hand, but since operation of recent model dSLR is essentially similar, I may be able to answer your questions.
Originally posted by Emirena 1.) I noticed when attempting to adjust EV compensation in manual mode that there is no indicator on live view nor the viewfinder overlay of any adjustment, however the camera menu takes any input I give.
In M mode (assuming you are using a modern lens with contacts on the mount), an EV bar scale should be present both on the rear LCD and in the viewfinder. Centering the indicator will provide the meter-recommended exposure. When EC has been set, the recommended exposure reflects that setting.
Live mode exposure emulation should show an estimation of the actual exposure such that if -2 stops EC was indicated with a centered bar, the viewfinder should appear darker than if no EC was set.
Originally posted by Emirena 2.) I attempted to test all three (additive, average and bright) composite exposure shooting with a 3-image base in a dark park with bright lamps...
I will defer comment on composite vs. in-camera HDR vs. bracketing except to say they may all be used to deal with your use case and that proper use of composite requires some practice. I prefer bracketing with merge done in post-processing for HDR and use the composite feature to "build" an image in-camera but not for usually for HDR.
Originally posted by Emirena 3.) Program Line mode -
In the simplest sense, the program line affects programmed auto-exposure (you set nothing) and does not affect any other exposure mode. Getting more complicated:
- The HyperProgram feature of P mode (override of aperture, shutter speed, or ISO) does not use the program line
- Auto ISO (any mode) also does not use the program line; it has its own rules
- The green button will generally reference the program line by default, but this behavior may be overruled by menu setting
- Various button actions may be defined by mode to use the program line by menu setting
The program line may be used to influence how changes are prioritized (DOF vs. freezing action), but is a pretty blunt tool if one wants to maintain a particular aperture or aperture range.
Being that I very rarely use P mode, I leave mine set to "normal". :o (edit: not pertinent to K-70) If one needs control over aperture in changing light and AE is needed, Av (auto ISO on) or TAv may work for you.*
Originally posted by Emirena just barely tested out a hand-me-down K-1000 1:2 55mm lens which has some very cool macro/depth of field capabilities at wider apertures.
Be aware that if one is using the aperture ring on an older K-mount lens to set aperture, the option for exposure automation is no longer available (the lens will stop down in M, B, and X modes only) and metering is limited to so-called stop-down measurement.
Steve
* I hesitate to recommend auto-ISO because I feel it is evil, but sometimes evil is necessary.