Olympus XA Questions

Arved

Arved

Member
Local time
5:38 PM
Joined
Jun 30, 2017
Messages
38
I just received an Olympus XA w/A11 flash. I found a user manual on-line (here), and I've searched on-line, but I still have a question I hope you can answer.

On the focus dial, the 8 foot setting is marked in red. What's the significance of this?

aTdHvAaNnKcSe,
- Arved
 
I believe it's for zone focusing. If you shoot at F11, then setting the focus at the marked setting is generally good for street and similar photography.
 
Congrats on the camera ! Reg. your question:

xa.jpg
 
I kind of thought of that, although 8' @f/11 gives a depth of field from 4.65 to 31 feet according to p. 14 of the user manual (which seems a bit optimistic compared to DOFMaster). f/16 extends to infinity, and if you're setting at f/16 to shoot the "sunny 16 rule," it works out.

Thanks for the quick reply!
 
Arved said:
... although 8' @f/11 gives a depth of field from 4.65 to 31 feet according to p. 14 of the user manual (which seems a bit optimistic compared to DOFMaster). ...
Click to expand...

DoF has absolutely nothing to do with what is actually sharp. It is all about what is acceptably blurred. The standards for what is "sharp enough" vary.

The XA's "snapshot" settings are likely based on 4x6 prints, what the tyro who doesn't understand f/stops and focus is likely to have made. The more detailed DoF tables that Oly provides are more likely based on the then convention of an 8x10 enlargement held at arm's length. Both are conventions dating to the previous millennium.

Today, images are frequently viewed on monitors much larger than 8x10" and many DoF tables and calculators use a higher standard for sharpness ("circle of confusion" was the old metric although some adjustment needs to be made for digital photosite sizes and mosaic array configuration as they introduce additional confusion).
 
Dwig said:
DoF has absolutely nothing to do with what is actually sharp. It is all about what is acceptably blurred. The standards for what is "sharp enough" vary.

The XA's "snapshot" settings are likely based on 4x6 prints, what the tyro who doesn't understand f/stops and focus is likely to have made. The more detailed DoF tables that Oly provides are more likely based on the then convention of an 8x10 enlargement held at arm's length. Both are conventions dating to the previous millennium.

Today, images are frequently viewed on monitors much larger than 8x10" and many DoF tables and calculators use a higher standard for sharpness ("circle of confusion" was the old metric although some adjustment needs to be made for digital photosite sizes and mosaic array configuration as they introduce additional confusion).
Click to expand...

So what kind of DOF scale should I be using to calculate hyperfocal focus distance?
 
Arved said:
So what kind of DOF scale should I be using to calculate hyperfocal focus distance?
Click to expand...

Which ever one uses a CoC that is appropriate for your use. Only you can decide what sharpness level you need to maintain and only you know how large you will be printing or displaying the images.

Hyperfocal distance calculation is merely a special case of normal DoF calculation. It is for finding what focus setting places infinity at the far limit of the DoF, based on the chosen f/stop and CoC.
 
Arved said:
Thank you. Those pages aren't in the manual I found on-line (linked in original posting). :bang: That makes perfect sense! :angel: LOL:D
Click to expand...

I'm making a note for my XA; ferider dispenses accurate info re hyprfocal distance. Thanks ferider

pkr
 
You must log in or register to reply here.
Back
Top Bottom