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 24 backgrounds ?



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January 18, 2016, 07:51:29 AM
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Offline lensoreat

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24 backgrounds ?
« on: January 18, 2016, 07:51:29 AM »
so,  i'm a little conflicted about backgrounds with this 24mm lens,   have to experiment more,   i want the foreground to be in focus,  but not sure whether the background should be ,  as in this shot,  a little out of focus (  i like that effect usually )  or should it all be in focus ? 

i think when the full frame appears,   the wider angle lenses will be really cool,   but then too,   will i have even more out of focus, at the same f stops--  and is that a good or bad thing ?   

( i mean i can use a point and shoot and have the whole shot in focus,   but that's no fun ......   )     dave

January 18, 2016, 12:28:23 PM
Reply #1

Offline Pacerr

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Re: 24 backgrounds ?
« Reply #1 on: January 18, 2016, 12:28:23 PM »
[quote author]  ...and is that a good or bad thing ?   [/quote]

Neither; it just is. It's up to you how you use it aesthetically. But the rule is that a smaller cropped sensor will produce more apparent DOF in certain situations.

Don't know what you're expecting there but that seems typical for the circumstances of that shot in the EXIF data.

I'll arbitrarily presume a subject focus distance of 4 ft and an aperture of f/8 based on your previous post. Stuff in the background is well beyond any expectation of falling within a 'normal' dept of field for sharpness. DOF is calculated at only about 3 feet.

If you'd manually set the calculated hyperfocal distance of about 12 ft you'd have been good from about 6 ft to the near horizon. You can easily set the HFD with an auto focus lens IF you know the desired hyperfocal distance to begin with. Just lock AF on an object close to HFD and re-compose as desired.

Here's a link to a DoF calculating program. Using the K200D as the entry for the APS-C sensor:

http://www.dofmaster.com/dofjs.html

Here's a program that'll build useful DOF / hyperfocal charts for any lens.

http://www.dofmaster.com/doftable.html

« Last Edit: January 18, 2016, 01:50:46 PM by Pacerr »
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January 18, 2016, 08:29:55 PM
Reply #2

Offline lensoreat

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Re: 24 backgrounds ?
« Reply #2 on: January 18, 2016, 08:29:55 PM »
guess i better finally learn all this hyperfocal stuff;   know some of the lenses - 'specially the older ones - have that information right on the barrel don't they ? ...... if i knew how to read it.

so if i didn't worry about diffraction in the old film days so much,  if i were in the old film days ( or the new film days for that matter ) normally one would stop the lens down to f16,  22,  etc to get the background in focus ?
   
what does tcom do to get all those good shots he gets of landscapes , etc ?