Digital cameras 101

[wazungy]

Hi all.

This is my first post, I hope I get everything right.
I was going over some holiday shots today and noticed a few that seemed to have an uneven exposure for a seaside image.
It is like the camera decided to change settings partway through the exposure.
The camera is a Canon A620. I love this camera. I am still learning but I am impressed with the great results (compared to my Canon A40).

Anyhow, the photos have been posted on the webshots site.
image 776 and image 778.

776 and 778 are descriptions of the settings the camera used for the shot.
I did not change setting between the shots (image 777 looks like 776 and shows the same info). The only difference I see in settings is the camera chose a different shutter speed for the images.
Why is half the water more blue? Even the relfections are different on one side and the other.  I highly doubt it is cloud reflections, as the waves are steep enough to reflect various bits of sky  from anywhere in the image.

What is going on,

how do I "correct this? I like the water on the right.


images link copy and paste into browser.

http://community.webshots.com/album/529500341pkvtGa

reply to a31415pugh@yahoo.ca and use "webshots" in your subject so I know it isn't spam.

Thanks,

Waz

[ShutterbugGail]

Hi wazungy and welcome to the Q&A Board!

The camera is a Canon A620. I love this camera. I am still learning but I am impressed with the great results

It is a great camera. Take your time learning it because it has a lot of sophisticated features. A suggestion if you're not already doing so, which relates to what I'll say below, is to shoot using P mode, not fully Automatic Mode. P Mode gives you much more control over such things as exposure compensation.

Why is half the water more blue?

I could be wrong, but I don't think it is a camera problem.  It really does look like an effect of the lighting and/or position of the clouds at the time you took the photos. Maybe another moderator will have a different opinion about the lighting.

If you're experiencing the same problem in photos of other subjects, that is how you can tell if it's a camera problem.

how do I "correct this? I like the water on the right.

If you have an image editing program that has layers, such as Photoshop, Photoshop Elements or PaintShop Pro), you can use contrast masking:

http://www.digicamhelp.com/contrast-masking/

When taking similar photos the next time, you may want to try exposure-lock and, possibly, exposure compensation.

http://www.digicamhelp.com/focus-exposure-lock/index.htm

http://www.digicamhelp.com/what-is-exposure-compensation/exposure-compensation-settings.htm

reply to a31415pugh@yahoo.ca and use "webshots" in your subject so I know it isn't spam.

We really don't reply by email but I'll send you a quick one reminding you to check back here for replies. Sometimes there can be more than one reply- most typically within a week of when you post a question - so you should  check back now and then on your own.

[Mike54]

Maybe another moderator will have a different opinion about the lighting.

I'll give it a look when I get home. Behind the firewall at work and I'm afraid I can't "see" it.  

[Mike54]

It really does look like an effect of the lighting and/or position of the clouds at the time you took the photos.

After taking a look I'd have to agree with ShutterbugGail on this one. Overall the image seems to be exposed properly but the reflection of clouds and light are creating the odd result.

[alp wazungy]

QUOTE:
It really does look like an effect of the lighting and/or position of the clouds at the time you took the photos.

I feel very uncertain about this.
If the water were relatively flat I would agree 100%.
As it is, there are waves and ripples all over the surface that should allow random reflections from all over the sky at any particular point on the water surface. In spite of this, there is a very well defined line (especially image 776) where water reflections on one side act differently than water reflections on the other. It almost looks like half the photo used a polarizing filter. On a surface with waves like that in this photo I would expect a much more gradual blending between light and dark areas in the sky.
I think something else is going on.

I do thank you for your input.
I WILL try using P mode in the future and I will look into those links you have supplied. I shall have a good time trying to "normalize" the water I am sure.
I will also look into trying to adjust the exposure better as the clouds in many of my shots are WAY over exposed (auto mode!).

Sorry about the email part of my message. I didn't know how this board handled replies. If I do have any email waiting, they will have to wait. I am performing maintenace on my main system (the workhorse) which I use for email.

Thanks,

Waz

[Deb]

Hi Waz, have you tried taking a few test shots to see if the effect you saw in the posted images resurfaces (sorry, couldn't pass on the pun)? If you haven't tested, I'd try shooting a blank sidewalk or concrete street (don't use flash) These surfaces are nonreflective. Then I'd try shooting a blue, cloudless sky (be watchful of the angle of the sun). If the effect reappears in these images too, then I'd suspect that the problem may be with your camera.

One the other hand, I just thought of one other thing. Some folks forget where their hands/fingers are relative to the lens when they shoot. While pressing the shutter their finger moves in front of the lens ever so slightly. When this is done, part of the image is blocked and can result in a darkening like what you saw in those photos. It can also occur on windy days where long hair, a scarf, etc. can momentarily blow in front of part of the lens. Do you remember if any of these things could have occured that day? Anyway, just a thought.