dblackard Loc: Rockport Texas

Ok, i am going to risk asking this because i really dont understand. I took a series of pictures in different apertures. All pics in 160 ISO, 48mm. now the first F/13 , it says 1/20 sec. the second i changed to 5.6 and it says 1/250 sec. i know how to change the Aperture but how dos the sec. change?? the last two i left at 5.6 but focused more on eyes and it was 1/60 sec. what does this mean. ( i am stepping up from the auto button so give me a break here)

Wabbit Loc: Arizona Desert

What mode are you using?

At any given iso your shutter speed and aperture make the exposure.

If you're in A (aperture priority) you're choosing the aperture and the camera is choosing a shutter speed to get you an acceptable exposure. When you change the aperture to a larger one your shutter speed will need to be faster. The combination is based on available light

snowbear

It sounds like you were in aperture priority mode, where you select the aperture and the camera picks the shutter speed. The difference in the last two may have been from the meter mode you were in. EXIF data would help you.

ace-mt Loc: Montana

Every time you take a photo there are 3 things that make up the exposure: shutter speed, aperature, and ISO. On manual mode you choose all 3. In aperature mode, you choose aperature and ISO, the camera picks whatever speed will complete its idea of proper exposure. this appears to be your circumstance.

micro Loc: Texas

his may help.

http://www.photonhead.com/beginners/shutterandaperture.php

dblackard Loc: Rockport Texas

thanks, that was good. i understand this but for some reason it never sunk in that since i was picking aperture and iso the camera was picking the shutter speed for me. i was trying to get bokah. but it seems to work better with my longer lens. was using a 18 - 105.

docrob Loc: Durango, Colorado

it means your camera is compensating for the Fstp changes

mooseeyes Loc: Sonora, California

It is all about the light. A certain amount of light reaching the "film/digital sensor" will produce the perfect exposure for your intended image. Too little light, and you are under-exposed. . .your shadows may block up on you (no detail/info). Too much light, and you are over-exposed. . .your highlights may be blown out (no detail/info).

ISO sets how sensitive your recording medium is to light; i.e., the film/digital sensor. For example, 3200 is twice as sensitive as 1600, which is twice as sensitive as 800, which is twice as sensitive as 400, which is twice as sensitive as 200, which is twice as sensitive as 100, etc. Once the ISO is set, the lens opening and the shutter speed work in an inverse relationship to control the proper amount of light that hits the film/digital sensor.

If lens opening gets bigger (more light comes in), then shutter speed needs to get faster to balance against the larger lens opening. If the lens opening gets smaller (less light comes in), then the shutter speed needs to get slower (letting in more light) to balance against less light let in by the smaller lens opening.

A fast shutter speed lets in less light than a slow shutter speed.

A large lens opening lets in more light than a small lens opening.

Lens opening (f/stop) generally will control depth of field. Large and open, narrow depth of field. Small and closed will render a larger depth of field.

A slow shutter speed will not likely stop movement or action. You will need a fast shutter speed to stop action; however, this will reduce the amount of light. . .requiring a larger lens opening to compensate.

You always need to be mindful of your shutter speed in certain lighting situation, as you may have to use a tripod in order to get what you want. Too slow of a shutter speed will not allow you to hand hold your camera, for the right exposure and a sharp image. Also, if you change your ISO, everything changes. For people learning, I would suggest you stick with ISO 400 until you get a really good feeling and understanding of how f-stop (lens opening) and shutter speed interact with one another.

When you are learning, just always think in terms of how much light is getting to the sensor, and how that proper amount of light is being determined. Once ISO is set, it is all about the relationship between lens opening and shutter speed.

francesca3 Loc: Sausalito, CA

I just want to acknowledge your response here ---> You took the time to explain things in way that is probably understandable to the person who asked the question, and you are one reason why I do love this UHH web site. VVN

Neweagle Loc: Wales UK

Mooseeyes, people like me came to the HOG to learn, and its people like you who are prepared to give time and knowledge to us newbies, that help us to learn. Many thanks for a great response to the questioner.
:thumbup:

dblackard Loc: Rockport Texas

yes, thank you so much. I read all of this stuff in books, online ect. but sometimes i just need an example of what f stop to use in a certain situation, or what shutter speed to use. that way i at least know where to start. the responses are great, thanks again.

Wabbit Loc: Arizona Desert

It means that your camera chose a slower shutter speed of 1/60th of a second when you chose the larger aperture of 5.6.

The meter in your camera decided that 1/60th was the shutter speed needed to get you an acceptable exposure based on the reading of the light being reflected off the eyes.

Even if you focused on the hair instead the eyes using a 5.6 aperture ,the camera would probably have chosen 1/60th of a second anyway.

If you took the same scenario, same subject, same lighting, same iso setting and used M (Manual) instead of A. You have the option of slightly changing the exposure yourself in more than one way.

For instance, it you wanted the pic to be a little lighter you could change the shutter speed from 1/60 to 1/50 or 1/40.

Or if you felt that it was too bright and you wanted to darken it up a bit you could raise the shutter speed from 1/60 to 1/80 or 1/100th.

But keep in mind that shutter speed controls movement.

Hammster Loc: San Diego, CA

I didn't see it mentioned, so here goes. I really like, and recommend, Bryan Peterson's Understanding Exposure. He really explains the big 3 (ISO, Aperture, and Shutter speed) well. With plenty of examples along the way.

projectmom3 Loc: Florida

Thank You Mooseeyes! I've been reading these posts for about 2 weeks since beginning a Photo 1 class (digital). The way you wrote and explained it, was better and simpler than the 6 week class I attended. Thanks for taking the time, us (newbies) and not/so newbies (but definitely rusty) and beginning at the basics in Manual Mode (frustration). I applaud you!! :)

ole sarg Loc: south florida

look at this site it will teach you much and it is hands on:

http://camerasim.com/camera-simulator/

go through the entire set of simulations. wish I had had this in 1957 when I first picked up a camera