Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
03-04-2016, 02:28 PM - 1 Like   #16
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,457
QuoteOriginally posted by dms Quote
Well yes, and yes the effect is very significant in the macro range, but for normal shooting distances the changes in H are not significant IMO.
In practice, that is my opinion as well. My personal rules of focus has been to consider the following when working with different formats and working distance:
  • There is only one plane of focus regardless of what sharpness is deemed acceptable
  • Practical DOF becomes thinner as format gets larger
  • The DOF you see in the viewfinder or in live view is usually not the same as on a mounted print or computer screen
  • Big enlargements tend to suck when viewed close up...plan appropriately
  • DOF will not cover for missed focus when critical focus is important. This is particularly important when working with extreme wide-angle shooting.
  • Wide angle lenses are fiendishly hard to focus
  • Adequate native DOF becomes dear when doing macro (e.g. 1:1 or higher magnification to the focal plane) regardless of format
  • The hyperfocal* is very real and readily available for small (24x36mm and smaller) formats at shorter focal lengths, and is very useful for many subjects and photographic styles. Use it, but keep expectations low.


* Technical term for when the far limit of DOF for a particular focus distance is at infinity.

03-04-2016, 04:26 PM - 1 Like   #17
Site Supporter

Join Date: Jan 2010
Location: Michigan
Photos: Gallery
Posts: 2,182
Also consider the distant haze.

For my type of photos there seems to be little need to focus at infinity.
( As long as the lens is calibrated at infinity)
In this 6x7 photo with a 90mm lens at f/16 the hyperfocal distance is about 13 metres,
at f/16 with a COC of 1/1500th of the frame height of 57mm
This one was with the RB67 so I did not think about Hyperfocal, just focussed on the more distant tree.
There is no reason to try to focus on the distant beach because of the haze.
In this 6x7 photo with a 103mm lens the hyperfocal distance is about 18 metres,
at f/16 again with a COC of 1/1500th of the frame height of 57mm.
This was a rangefinder so I just set it somewhere near 100 ft ( 30 m) on the scale, with about 1.5 degree of tilt.
The near DOF calculates to be at about 8 meter, about where the black lamp post is on the left side.
Again, the distant buildings were a bit blurred I think more by the haze than by the focus point selected.

  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
aps-c, change, depth, factor, hyper focal, lens, lenses, pentax, question, scale, sensor
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
Lens mechanics question: Aperture vs focal length joseph_me Pentax SLR Lens Discussion 8 10-06-2015 10:46 PM
Middle focal length question (40 to 60mm) interested_observer Pentax SLR Lens Discussion 11 11-28-2014 12:44 PM
Quick Macro Focal Length Question... vagabond79 Macro Photography 7 08-26-2014 04:33 AM
hyper-focal distance with a kit lens? adwb Troubleshooting and Beginner Help 12 02-17-2010 10:42 PM
terminology: hyper-program vs hyper-manual WMBP Pentax DSLR Discussion 18 03-25-2009 04:33 PM

All times are GMT -7. The time now is 02:16 AM. | See also:, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]