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Old Oct 8, 2006, 5:44 PM   #1
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Maybe I posted this in the wrong place. Wasn't positive where to ask for help.

Below is my post to the Critiques and Techniques forum. Can anyone help me? I'm not sure if it's something I did or what. I'm also following this with a second photo of blue sky taken a few weeks ago that seems fine. (Is it possible to send more than one photo in a post?)

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This was taken at the fair today as we were leaving. It was around 3 p.m. and somewhat cloudy, but the sun was shining. I was rushed to take the photo as there is a policeman just to my left asking me to move out of the road.

I'm still trying to adjust for my photos coming out darker than I expect, but this one has me confused. If you look in the top left hand corner and along the top, the sky is bright blue. But, just below it the sky is baby blue green. Is this my lens doing this? I was using the 18-55 kit lens.

I forgot to add, I do have a filter on the lens, but it is only the 1A, mostly for protection. The lines in the photo to the left of the trees on the right are towers. At first I thought they were a scratch on my lens.
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Old Oct 8, 2006, 5:45 PM   #2
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Second image from a few weeks ago. Forgot to mention that I'm using a K100D with the kit lens and the filter. I know I had the same filter on the camera when this photo was taken.

Thanks for any help on this.
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Old Oct 8, 2006, 6:40 PM   #3
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HI nhmom

I am far from any expert on this however. I am Going To guess it is That you Just Caught the Right angle and maybe that area is Sun reflecting Off the water Vapor in the Clouds. Sort Of a Prism effect. Just a Guess. If it were a defect in anything It would have shown In all your pictures.
If i remember Correctly those are the Bud Clydales from the Marrimac Brewery.

Great Shots

Phil
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Old Oct 8, 2006, 9:19 PM   #4
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Yes, they are the Clydesdales from Merrimac. They are beautiful horses and the three year oldson of my friend was fascinated with them.

I am going to do an experiment tomorrow. About 12 days after I had taken the seagull photo, I had taken a photo straight up of the sky to see if any spots appeared. I didn't see any spots. But, as I'm taking that photo into PSE4 and doing a color check on it at random spots around on it, I am getting two different color readings. In the upper left hand corner I get the hex code #333399 about 10 inches down and 8 inches across the top left hand corner. The entire rest of the image it is #336699.

It doesn't totally coincide with the off coloring in the Clydesdale photo as it is all across the top, just more on the left hand top corner. It could just have been that the sky was two different shades of blue that day. And, a photo with sky in it I took 24 hours later, the sky is the same color all the way across.

So, I guess never mind the experiment. Maybe you are right and it was just the water vapor in the clouds. Especially since all my other photos are the correct colors.




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Old Oct 8, 2006, 10:01 PM   #5
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One thing I found about looking for dust spots on the sensor. Take the kit lens and set it at 55mm, that way you can set the aperture at F40 (I believe). This will show the dust the best. Don't worry about shutter speed. Now, take a picture of the clear blue sky fairly high up. Normally your pictures won't be at this extreme of a setting and often won't show the dust.

One thing you will notice when looking at the sky, many times you have to look up at least 30 degrees to see clear blue, as you get quite a bit of atmospheric pollution down low. Astronomers know this and usually won't take pictures of anything that is less then 45 degrees high. Straight up is the least amount of atmosphere you can look through. Anyway, because of this, I think it is quite common not to have the sky look true blue all the way to the ground, unless you are in the high mountains on a clear day. One thing you will notice if you drive to the mountains, say at5000', how much bluer the sky looks. After reading all this, I may be confusing the issue. What I'm trying to say is many times the sky will look different at the top of a picture then at the bottom- Bruce
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Old Oct 8, 2006, 10:59 PM   #6
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Bruce,

I probably confused the issue by bringing up the fact that I had taken the sky photo for the spots. I did take it at 55mm, but didn't change to f/40. It was at f/8. I was looking straight up (as well as I could and not fall over :lol As for elevation, I'm fairly close to the ocean so probably not too high at my house where I took it. I was near some trees, not really in a fully open area. So, I could redo in a totally open area again.

It should be clear again tomorrow. So, I'm planning on taking some more sky shots to see if I still see the different shades of blue. I guess it just stood out in this one as they were different hues of blue, not just different shades of the same hue. Hadn't ever seen that before. (Not that I'm a pro at this or anything!)

Thanks for the input.

Patty
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Old Oct 8, 2006, 11:14 PM   #7
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i am going to guess the difference in the blues is the exposure

in the top one the sky is overeposed a bit

where as in the second photo it is exposed more correct

the over exposure resulted from exposing correctly for the horses etc


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Old Oct 9, 2006, 7:59 AM   #8
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Thanks for all the input on this. I am feeling much better about the shot now. I had been focusing on the histogram all day when taking photos. Still learning what to look for. Wasn't sure if I'd changed some setting to something I shouldn't have.
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Old Oct 9, 2006, 9:07 AM   #9
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Patty - Here is a very good article on using histograms. I have my camera setup to give apreview after the shot with a histogram included. You get very use to judging the histogram after each picture if you do it all the time. I seldom look at the picture, just the histogram to see if the shot is exposed correctly. I also have the camera set up to flash overexposed highlights, so between the histogram and the flashing highlights, it makes it much easier to judge exposures. I can tell you it's an ongoing learning thing and I haven't mastered it yet- Bruce

http://luminous-landscape.com/tutori...stograms.shtml
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Old Oct 9, 2006, 7:34 PM   #10
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Thanks, Bruce. Someone had pointed me to that same article last week on histograms. That is what made me start looking at them. Went out today and took some more photos. It was nice and sunny all day. Haven't downloaded any yet to see how they came out. I need to start focusing on one thing. I was using my new 50-200 lens AND trying to read the histogram AND taking the same shots in A, P, TV and AV.

We'll see. Thanks, again.
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