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When I use the manual focus mode, I usually adjust it until the object I care about comes into focus. But sometimes the object is not there yet, so I'd like to know if there is a way for me to tell the camera to focus X meters away. This is with the Sony NEX-5R.

An example of when this is needed is when I'm setting up my camera to shoot a train that will appear at a specific point ten meters away from me. I can't focus on the train since it's not there yet, but I need to set the focus ahead of time to have a good chance of taking a shot. (This is a long exposure, low-light shot.)

Autofocus does not work reliably for this lens under low-light, and if I wait till the train comes by before I focus, I might miss the shot, and in any case, it's hard to manually focus on a quickly moving train.

Is there a way for me to tell the camera to focus X meters away, other than finding some other object X meters away, moving the camera if necessary to find such an object, focusing on it, and then moving the camera back to the desired position?

Or is there some other solution to this problem that I'm overlooking?

A special case of this problem is needing to focus on infinity. As I adjust the focus, I don't know which point corresponds to a focus at infinity.

Kartick Vaddadi
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    Use a camera/lens that includes a distance scale on the barrel of the lens. – Michael C May 31 '14 at 18:53
  • Normally, when half pressing shutter, it triggers autofocus. Can your camera assign this function to a different button? if so, you can use the method of finding some other object X meters awaybut -big difference- you can fix the cammera in tripod alone and take a seat near by waiting for the train to come. – Horaciux May 31 '14 at 21:56
  • Michael, I thought the distance scale on the barrel of the lens is only for zoom and not for focus. Horaciux, I wouldn't want to reassign half-press for this purpose. I probably use the existing function more often, and in general, I don't want to customize the buttons, since non-standard assignments makes it harder for me to use the camera. – Kartick Vaddadi Jun 01 '14 at 03:02
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    "I don't want to customize the buttons, since non-standard assignments makes it harder for me to use the camera." A lot of photographers live and breathe by "back button focus" or the equivalent - sure, it's more complicated than your P&S, but it's giving you more control over the shot. Sometimes you need to learn new skills in order to do new things. I'd say that ruling this out because it might make things "harder" for you in the short term is the wrong decision in the long term if you want to become a better photographer. Rant ends :-) – Philip Kendall Jun 01 '14 at 19:00
  • For the infinity focus question, see e.g. How can I find infinity focus on a kit lens with no markers? – Philip Kendall Jun 01 '14 at 19:03
  • Thanks, Philip. I'm willing to customize once I've used the camera enough that every single function becomes intuitive, and I'm strongly convinced that the existing function attached to a button is the wrong one (for me). Till then, I'll stick with the defaults. Besides, I don't want to reassign such a commonly used function as autofocus on half-press. Maybe once I develop more expertise, I'll change my mind, but for now, I do have to do what makes sense to me as of now. – Kartick Vaddadi Jun 02 '14 at 12:36
  • @MichaelClark I checked, and none of my lenses have a scale for focus (or zoom, for that matter). And, since there are many factors to juggle when selecting a lens, insisting on a distance scale is not practical for me. – Kartick Vaddadi Jun 07 '14 at 12:57
  • @KartickVaddadi Then for you there is no practical solution to your question as worded. – Michael C Jun 07 '14 at 18:05

1 Answers1

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Switch to manual focus, and focus on the track or other similarly distant object.

lenshead
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