Back focus problems

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imported_ganna
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Joined: Tue Nov 07, 2006 11:41 am

Postby imported_ganna » Tue Aug 27, 2013 5:12 am

I saw this interesting article  http://www.johanfoto.com/2013/07/foc...se-back-focus/

RonBoyd
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Joined: Sun Jul 09, 2006 10:23 am

Postby RonBoyd » Tue Aug 27, 2013 10:41 am

I couldn't make your Link work. Try this one: http://www.johanfoto.com/2013/07/focus-recompose-back-focus/ Nice catch, though, thank you.

ggroess
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Postby ggroess » Tue Aug 27, 2013 12:51 pm

This is why you should have the old hash marks on the lens so that you know the effective depth of field and can use it as a tool rather than fall victim to the possible errors.

http://imgur.com/SY7s1lv

Notice the lines on the lens with the f numbers?  To use these you focus your camera on the subject, then based on the f number you can shift the focus ring to line up with the front of the depth of field or the back.  If you wanted more back depth you moved the focus to the front.

Greg

imported_ganna
Posts: 460
Joined: Tue Nov 07, 2006 11:41 am

Postby imported_ganna » Tue Aug 27, 2013 3:00 pm

Thanks Greg. I think one of the errors of the digital era is that we are in such a hurry and just fire away without planning and thinking  :)

Niels Rasmussen
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Joined: Wed Jun 01, 2011 11:02 am

Postby Niels Rasmussen » Thu Sep 26, 2013 2:44 pm


This is why you should have the old hash marks on the lens so that you know the effective depth of field and can use it as a tool rather than fall victim to the possible errors.


I agree entirely but there is a trend for removing these from lenses, so yet another simple and practical photographic method morphs into arcane knowledge.

ggroess
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Postby ggroess » Thu Sep 26, 2013 4:09 pm

I wonder if they will keep this on "pro" level lenses...
Wouldn't that be nice....

Greg

Niels Rasmussen
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Joined: Wed Jun 01, 2011 11:02 am

Postby Niels Rasmussen » Thu Sep 26, 2013 11:14 pm

I have a couple of Nikon pro level lenses but's only on the older AF or MF lenses that you get any kind of DoF scale. There are other little niggly things that bug me by their absence such as a simple screw thread for a cable release. Nowadays you have to buy these incredibly expensive remote cables (or whatever they call 'em). Jeez, I'm sounding like my dad and he's been dead 30 years! To get back to something approaching the original point, I tend to focus manually using the entire viewfinder disregarding if necessary the focus point indicators. If the subject is off centre (nearly always) then I'll focus off-centre. It does help to have a bright screen and fast lenses though!

ggroess
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Postby ggroess » Thu Sep 26, 2013 11:25 pm

I hear all that...

I miss the split prism focus screen and the manual cable release as well.  Currently I set my camera up with the self timer for long shots.  Trip the trigger and let it count down to the shutter release without me touching the body.  It has helped my landscape in a huge way. 

Greg

sjordan93436
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Postby sjordan93436 » Fri Sep 27, 2013 4:02 am

Heck, I really miss the sportfinder!  It was a pentaprism replacement that allowed the back screen to swivel up.  On a Canon F-1.  Great camera, I miss it.

I do not miss eye controlled focus.  It did not work for me.


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