[PhotoNewt]

Originally Posted by dimitrz

Just wondering if I keep a shell towards the right and focus on infinity wouldn’t one of the two happen a) Shell will get blurred because focus is on infinity ? & b) Incase the shell is still focused wont the aperture come down to F4 perhaps?

This is easier to do with an SLR as you can push a button and check the focus of your foreground object before taking the picture. Having said that when you focus to infinity at wideangle with a very small aperture, you are going to get aceptable focus from around 3-5 feet (depending on lens) to infinity. If you focus at the hyperfocal distance (again easier on an SLR) your area of DoF for 24mm at f/22 may start at around a 1 feet from the lens.

Like everything in photography you need to go out and set up a test scenario; get a wide measure tape and lay it on the ground, set the focus to infinity, close down the aperture and take a photo - open up the image on the computer and read the distance when the focus is sharp enough for you. That way you will know for sure how your camera/lens combination works.

Never realized this is possible I though to get a better DOF you had to keep the aperture as near the smallest (F8 being the smallest for my camera ) - what you mentioned a real good to know information – thanks

This is an optical property of all lenses - the way it goes is as follows:

If you use a lens at wide open aperture, your focus is going to be soft and you may have purpule fringe resulting from sperical and chromatic aberration. This happens when the extreme border of the lens bends the rays of light and cause them to focus a little in front of the focal plane. This cause the image to look a little fuzzy.

As you close the aperture one or two stops, most of the border light rays are blocked by the diaphragm and spherical/chromatic aberration decrease until becoming negligible - you will experince progressive sharpness of the image and better color contrast.

As you approach the smallest aperture the light rays to bend excessively around the small opening dispersing at the other side causing the focus to change from a point to a small circle. This again causes softness on the focus and makes the image a bit fuzzy.

This is why most SLR users will shoot with the aperture set about 2-stops below wide open when maximum image quality is needed. Can you use wide open or the smallest aperture, yes and you should. You just need to be aware of these optical problems and judge when those are acceptable to you.

When I take a landscape on my camera I know that diffraction will start at apertures below f/11, at f/16 is acceptable and more visible at f/22 (I have experimented and found this out). I set my initial aperture at f/22 and take the shot, but I also take exposures at f/16 and f/11 - examine them closely on the computer and decide how much diffraction I am willing to accept. With proper sharpening, expansive landscapes usually look great at f/22.

Regarding softness I believe Sony DSC H2 by standard shoots a bit soft – I have an option to increase the sharpness in setting due you think I should tweak it a bit ? should the tweaking be doen for all photos or only for selected landscape photos ?

You should try to avoid this. The sharpening routines on most cameras can introduce artifacts to the image. I would suggest leaving all your in-camera image parametes (sharpness, saturation, contrast and hue if present) on neutral, then open the image on your favorite software and do the sharpening, saturation and contrast adjustment there.

To be quite honest I really appreciate your interest, patience & effort in trying to rub off some off your immense experience & knowledge to me through the forum.

My father was a freelance photographer, I have been attached to a camera in one way or another since I remember. I started using a manual SLR when I was around 8 years old, have read a lot over the years and have been around many professional photographers who taught me a lot of what I know and help clarify the tought questions I had...funny but in the end I did not become a professional photographer as everyone expected.

Thanks for the tip – I’ll try to use Program mode ( something which I had totally ignored ) more often from now on .

I do not know how your program mode works, in my camera the [P] option works similar to the fully automatic mode but it allows full access to all the advanced function such as mirror lock, flash exposure and many others not available on full auto. When you press the shutter half-way, the camera suggest an aperture/shutter combination - just as in auto - but there is a little wheel conveniently located behind the shutter button that allows to shift the exposure by simply turning the wheel.

For example, if I want to take a quick candid portrait I point and get an initial exposure -> the camera may suggest f/8 - 1/125. I would like to blur the background a little more so I need a larger aperture, so I rotate the wheel and it takes me through equivalent exposures: f/4 - 1/500 -> f/2.8 - 1/1000 and voila!, f/2.8 works for me so I press the shutter and take the photo, all this took less than a couple of seconds while looking throught the viewfinder.