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11-12-2007, 04:44 PM   #16
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Pat. The EXIF data shows that this was shot at 18mm so I suspect that this was the kit lens. It's known for vignetting at full wide and the filter is usually deeper than a UV so that's most likely why. Move the lens up to 20mm or so and there wouldn't be an issue.

11-12-2007, 04:45 PM   #17
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Wouldn't be without my polariser (I use the Hoya Pro 1 D)

This shot was taken in quite flat lighting, the polariser transformed it !!

simon

11-12-2007, 05:42 PM   #18
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Here are a couple of more pics I took today...Next time I will take a tri pod with me. I tried to capture the corner of the sun on both shots...The first is without the polarizer and the second is with it...





I have taken many pics like the first one and have never had good results...The polarizer atleast for me, has changed things a little...Peter..I really appreciate the way you have taken the time to explain things..Infact all of you..''thanks a bunch!!!

p.s. What is vignetting? I read about it, but have not found an explanaition..
11-12-2007, 05:44 PM   #19
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QuoteOriginally posted by Peter Zack Quote
Pat. The EXIF data shows that this was shot at 18mm so I suspect that this was the kit lens. It's known for vignetting at full wide and the filter is usually deeper than a UV so that's most likely why. Move the lens up to 20mm or so and there wouldn't be an issue.
The lens I used was not the Kit lens but the new 18-250Tamron lens hooked unto a K100D super

11-12-2007, 05:53 PM   #20
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Here is another pic I took today shooting away from the sun with the polarizer..I have never been able to take such a rich photo..

11-12-2007, 05:59 PM   #21
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Vignetting is light falloff in the corners of the image, so you get darker corners. You can fix it in a lot of raw converters, such as ACR.

Wikipedia is ok for these terms:
Vignetting - Wikipedia, the free encyclopedia
Vignetting: Optical: Glossary: Learn: Digital Photography Review
What Is Vignetting?
11-12-2007, 06:03 PM   #22
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Vignetting is the dark corners caused by the lens and sensor picking up the edge or shadow of the front ring/hood or in this case filter collar. If you look at your first CPL picture. You'll notice the darker shadow around the corners of the shot. Sorta makes you're image look like it was shot down a tunnel.

Last edited by Peter Zack; 11-13-2007 at 04:43 AM.
11-12-2007, 06:22 PM   #23
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Oh, I see it..Strange..I have not noticed that before....I suspect that is a draw pack from an 18-250 lens..Well, I can't complain. That looks easy enough to fix in cs3

11-12-2007, 06:30 PM   #24
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All very nice. That does make sence at 18mm
11-12-2007, 09:40 PM   #25
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polariser

This was taken on a bright sunny day with a polariser on my k10d with the Sigma 17-70.For scenery shots on a bright day i wouldnt be without one.
11-12-2007, 09:59 PM   #26
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polariser

[IMG]http;//lh3.google.com.au[/IMG]
11-15-2007, 01:36 AM   #27
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hi jgredline,
which cp do you use, if you don't use a thin one, you have more vignetting at wide angles, especially 18 mm and wider... your is thin one????
cheers
halil
11-15-2007, 06:16 AM   #28
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Yep, good thing to learn (as well as how ISO/shutter speed/f-stop interact, DOF, composition, etc....) Buying gear is fun, but I believe fundamentals are more important.

QuoteOriginally posted by jgredline Quote
I am still trying to understand ''stops'' and so forth
You really have a K110D, K10D, D200, and are thinking about buying a *ist DS? Not to mention you buying BOTH DA* lenses? You do understand what f/2.8 means now, right?
11-15-2007, 09:31 AM   #29
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QuoteOriginally posted by hll Quote
hi jgredline,
which cp do you use, if you don't use a thin one, you have more vignetting at wide angles, especially 18 mm and wider... your is thin one????
cheers
halil
Halil
Thanks for the advice..Infact I do not have the thin one, I have the thick one...I wanted the thin one because it cost a little less money, but they were out of it..I also did not want a Hoya because I have had terrible luck with the glass coming loose on the ring...

I am thinking that the vignetting problem is caused by the Tamron 18-250 lens because not that I know what it is, it does it with and with out the polarizer or the filter. When I extend the lens to 20mm it is gone...It does not bother me too much because it is easy to fix in photoshop, and really that lens works very well even at 250mm..Really sharp...so it is a good compromise..However, it is good to know that the thickness makes a difference...I will remember that for future purchases..
Thanks javier
11-15-2007, 09:53 AM   #30
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QuoteOriginally posted by jgredline Quote
Halil
Thanks for the advice..Infact I do not have the thin one, I have the thick one...I wanted the thin one because it cost a little less money, but they were out of it..I also did not want a Hoya because I have had terrible luck with the glass coming loose on the ring...

I am thinking that the vignetting problem is caused by the Tamron 18-250 lens because not that I know what it is, it does it with and with out the polarizer or the filter. When I extend the lens to 20mm it is gone...It does not bother me too much because it is easy to fix in photoshop, and really that lens works very well even at 250mm..Really sharp...so it is a good compromise..However, it is good to know that the thickness makes a difference...I will remember that for future purchases..
Thanks javier
Vignetting appears in ALMOST every wide angle lens. Usually improves when you stop down a little and it is expected to be more pronounced in mega-zooms like the tamron.
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