Go Back   Steve's Digicams Forums >

LinkBack Thread Tools Search this Thread
Old Sep 22, 2007, 1:27 AM   #1
Junior Member
Join Date: Sep 2007
Posts: 1

In the manual mode on my S700, the f-stops in manual mode jump from F-6.8 directyly to F-13.6 with no abililty to select either f-8 or f-11. These are two very common f-stops I have used for landscape and portraits on my old Canon film cameras. Am I missing something here? In Program mode, I have been able to shift the program to cover the f-8 and f-11.2 f-stops.
RoadRunner Ron is offline   Reply With Quote
Sponsored Links
Old Sep 22, 2007, 8:18 AM   #2
Join Date: Jun 2003
Location: Savannah, GA (USA)
Posts: 22,378

I'm not sure why it would limit you, unless it's because the program mode is showing you effective versus actual aperture and the physical aperture iris design doesn't have that many steps (I've seen that from time to time with some digital cameras).

Is it the same way, regardless of focal length (your zoom setting). I can see why it may want to llimit it on the wide end of your lens (which is a focal length of only 6.3mm), to help prevent diffraction issues. Keep in mind that aperture is a ratio between the focal length of the lens and the apeture iris diameter. So, an aperture of f/8 is pretty small for that zoom setting.

You probably don't want to use apertures that small (higher f/stop numbers) anyway, unless you're shooting closeups where you have a shallower Depth of Field.

Because of diffraction limitations with a smaller lens design you see on current non-DSLR camera models, you usually need to stay towards the wider aperture settings (smaller f/stop numbers) to get the sharpest images, especially towards the wide angle end of the lens.

That's mostly because the actual focal length of the lens is very short on a non-DSLR camera model like this, and the actual aperture opening becomes quite small. So, stopping down too far can cause diffraction issues leading to softness with some models.

Keep in mind that you have *much* greater depth of field for a given aperture and subject framing on your type of camera, because you have a narrower angle of view (more apparent magnification) for a given focal length.

Depth of field is based on the actual (not 35mm equivalent) focal length, focus distance and aperture, and you'll be able to use a much shorter focal length to get the same framing using a camera like your S700. That's how they can make it so small with a lens with that much apperent focal range. ;-)

Hence, you'll have much greater depth of field than you did on a 35mm camera using something like a 36-432mm lens for any given aperture and subject framing.

The actual focal range of the lens on the S700 is only 6.3-73mm (which gives you the same angle of view/apparent magnification you'd have using a 36-432mm lens on a 35mm camera).

Because this camera has a very small sensor compared to the size of 35mm film, a much shorter focal length lens can be used to give you the same angle of view that you'd need to use a much longer focal length to achieve on a 35mm camera.

See this handy Depth of Field Calculator to get a better idea of how that works (making sure to use the actual focal length of your lens, which is 6.3mm on it's wide angle end, and 73mm if you're zoomed in all the way to it's long end). Your Fuji S700 is one of the cameras you'll find in the drop down list.


JimC is offline   Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -5. The time now is 7:16 AM.