Advice please / my first Prime Lens

[mrca]

Bokeh is the quality of oof areas, some claim it is only lights forming circles, cat's eyes or multi sided. Depth if field refers to how much is in focus. Choice of dof is an artistic decision that is critical for my portraiture and for flowers, it is your choice to decide how much dof is your vision for the shot. You may want tack sharp from front to back or you may want to isolate and emphasize a portion of the flower by keeping only that area in focus. Some folks who want deep dof will shoot several shots at different focus and stack them. I shoot in manual so my exposure doesnt change as I recompose a shot but also so I can choose my aperture/dof. Aperture priority would work where you get to choose the aperture and the camera sets shutter speed.

 

[EJA64]

Apertures (F/stops) are fractions, so large numbers are small openings, and small numbers are large openings....as 1/8th of a pie is smaller than 1/2 of a pie. Large apertures-like F/1.8, F/ 1.2, etc-produce great Bokeh (background blur), but have a shallow depth of field. So, at such apertures, the central part of a flower-the tip of a stamen-will be sharply focused, but petals, etc, in front of, and behind, the stamen will be blurry. If you want more of the flower in sharp focus, use a higher numbered (smaller) aperture....F/5.6, F/8, F/11, etc. Then more of the flower will be sharp...but the background will be sharper, too, due to the deeper Depth Of Field (DOF). Get in the habit of putting you camera on a tripod. Also, if your camera has a DOF Preview feature, use it. That will let you see what the image will look like-bright, or dark, sharp, or blurry, before you shoot. Also, before you shoot, set your camera's timer, so that it waits 10 seconds after you press the shutter release before it shoots the image. That, plus the tripod, will eliminate hand shake blur. As the aperture gets smaller (higher number), for more sharpness, you should either add more light-via a flash-or use a lower numbered shutter speed (1/30th of a second rather than 1/200th of a second), to increase the exposure. The P (Program) mode may be Ok some of the time, but when seeking sharpness, or Bokeh, use the A (Aperture Priority) mode more. Set a higher number aperture for more DOF / sharpness, and a lower number aperture for more background blur. Adjust the aperture up, or down, until all that you want sharply focused (stamen plus petals, etc) is so sharply focused. Bokeh actually can involve foreground blur as well as background blur, but most photographers set it up to be mostly, or all, in the background. What is actually in sharpest focus is a single point that you focus on. Everything else is somewhat out of focus, but can be sharply enough in focus to fool the human eye a bit. The area-front to back- which is in "acceptable focus"-seeming quite sharp to your eye-is called the Depth Of Field....DOF. It may be several millimeters deep, or several inches, or several yards, or whatever. An aperture of F/1.2 will have a very shallow DOF, only a few millimeters deep. An aperture of f/16 can have a DOF dozens, or hundreds, of yards, or more, deep.