Questions about lens's and manual shooting

Hello!

Well first of all. "aperture" in a nutshell is the opening that determines how much light is "collected" or hits the sensor. Shutter speed is how long the sensor is exposed to light.

This link Click might explain better than I can.

 

The only native m4/3 macro lens is the Panasonic Leica 45/2.8, which happens to be quite expensive. A cheaper if bulkier option is a Zuiko 35/3.5 Macro 4/3 lens with a MMF-1 or MMF-2 adapter which will give you full autofocus and aperture control. Cheaper again is some kind of old film camera macro lens along with a cheap adapter. This will be manual focus and manual aperture. You can take your pick amongst various brands - Canon, Nikon, Pentax, Olympus, Vivitar, etc.

 

If you want to shoot fully manual where you set the aperture and the shutter speed it is a learning process. I suggest you shoot a series of shots in P mode where the camera chooses the combination of aperture and shutter speed. Then study the exif to see what the camera chose and try to work out what is happening.

The next step would be to repeat the tests in A mode (for Aperture Priority) where you choose the Aperture and the camera chooses the shutter speed. The aperture is the size of the opening that lets the light in and is measured in relation to the focal length of the lens as an f number. You will find the large apertures which paradoxically have small f numbers like 2, 2,8, 4 etc will only have a narrow range in focus with blurred backgrounds. If you reduce the aperture to say 5.6, 8 more of the background will be in focus and finally very small apertures like f 11, 16 and higher will have most of the background in focus. Again study your results and the exif to understand what is happening.

Next set your camera to S mode for Shutter Priority. Here you choose the time the shutter stays open in fractions of a second and the camera chooses the Aperture. Short shutter speeds like 1/500 or 1/1000 are great for freezing the action in sports to avoid blur. Again review your results from the exif.

When you have a grasp of the role that aperture and shutter speed play in the image you capture you are ready to try M mode (for Manual) where you set both A and S to get just the result you want. I've yet to reach that stage!!

 

Aperture has 2 effects , as Kade said the amount of light entering and also increasing or reducing the depth of field.

Most lenses are not optimal to use wide open in terms of sharpness hence by closing the aperture you use only the central part of the lens.

Shutter speed in any camera ( I mean even in Zenit , Fujica and some other not the most user friendly cameras) it should tell you the right exposition, old school was an arrow, from the recent SLR and DSLR it tells you by making the right shutter speed blink. Compare the results obtained at the same aperture in A and M mode then you will know exactly how it works. The best way to learn is to practice.