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I have a Nikon D5300.

  • Mode: Manual
  • ISO: 100 (Bright Daylight)
  • Aperture: f/5.3
  • Shutter:1/80
  • Lens: 70-300mm

I am trying to find a way to focus on multiple objects, in my case, a bouquet of flowers. I just want the focus on, lets say 3 roses, and rest is out of focus. I am in manual mode. I tried setting the focus point to 9, 21 and even 39 points. Focus mode is set to AF-A or AF-C. Still I could get only that one rose in focus with rest blurred out.

Is it even possible? Thanks for any advice!

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  • \$\begingroup\$ It would be helpful to add an example shot to your question highlighting the problem. \$\endgroup\$ Commented Mar 20, 2017 at 11:25
  • \$\begingroup\$ I shall add an exaample image once I get hold of one. \$\endgroup\$
    – Java_User
    Commented Mar 20, 2017 at 14:01

2 Answers 2

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If you have regular lens there is only one plane field that is in focus and its norm is perpendicular to the sensor. Period.

If you have tilt lens there is only one plane that is in focus but it may be, as name says, tilted with respect to the sensor.

If you want to make 3 roses in focus, use the angle where they are in focus. There is allways an angle since three points define a plane (except for three points in line). Any three points are in (at least one) plane. Four points define a sphere fully.

Another way around is to merge three or more images together. Shoot multiple images with each rose in focus and play with it in postprocessing.

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    \$\begingroup\$ Almost an aside: the focal plane is not always parallel to the sensor. See e.g. my question here and the links from there. \$\endgroup\$
    – Philip Kendall
    Commented Mar 20, 2017 at 11:23
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    \$\begingroup\$ What we call the plane of focus in photography is only theoretical. In reality lenses have a field of focus. Without correction the field of focus is curved like the inside of a portion of a sphere with the camera at the center. Even the most highly corrected lenses have a field of focus shaped more like a lasagna noodle that a flat plane. \$\endgroup\$
    – Michael C
    Commented Mar 20, 2017 at 13:05
  • \$\begingroup\$ Thanks. But it went a bit over my head since I'm pretty noob on this subject. Looks like I need to resort for multiple exposure. Not sure though. \$\endgroup\$
    – Java_User
    Commented Mar 20, 2017 at 13:58
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    \$\begingroup\$ @Java_User The gist of what went over your head is "it's a lot of work and there is a lot to learn". Really good photos are usually the result of more effort than many people imagine (and a lot of experience and research) and a set of compromises that achieve the desired result. \$\endgroup\$
    – user50888
    Commented Mar 20, 2017 at 16:19
  • \$\begingroup\$ @MichaelClark Good point. But to be sure, the field of focus is still a two dimensional field (like a sphere surface), right? \$\endgroup\$
    – Crowley
    Commented Mar 21, 2017 at 11:42
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Like Crowley said. If you truly want multiple planes (technically, spherical shells) of focus, take a look at plenoptic cameras. The math involved as well as the optical engineering is pretty slick.

However, you're probably asking how to tell your camera to select multiple objects and use its "fuzzy logic" to adjust the aperture (for depth of field) and the median focus distance to try to optimize focus across the designated subjects. I don't have the user manual for your camera, so you may want to read up to see whether multiple targets is enabled when in manual mode.

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  • \$\begingroup\$ Thanks for your answer. Yes I want to focus multiple targets. I wonder how does the Auto mode does this with 18-55mm lens. Though I have also tried lowering the f stop but nothing worked out. \$\endgroup\$
    – Java_User
    Commented Mar 20, 2017 at 13:57

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