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07-20-2009, 02:03 PM   #1
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K20 Newbie Photo Question...

Hello All. I've seen some excellent info on here...I've just upgraded from a K100 and have a question on a picture I took. I'm not sure what to post, but I'll start with the bright jpeg from the raw file [using photo lab, no other processing]. I'm creating an HDR, but I'm posting only the two extremes. In the fast exposure 1/2000 the darks are very dark, noise free, at ISO100, but the slow exposure 1/125 , still ISO100 looks very noisy, especially in the grass and the reflection toward the left of center. Is this noise or am I being fooled by the dew, reflections and the light fog? It has an HDR look before the processing. I'm also having a hard time with low-light focus, so that may also be an issue. The lens is a sigma 18-200 at 18mm, f3.5.

Thanks...

http://www.scorpion-bowl.com/WebHost/IMGP0476.jpg

http://www.scorpion-bowl.com/WebHost/IMGP0480.jpg

07-20-2009, 02:10 PM   #2
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I can't seem to find any noise, just a but-load of PF. Maybe if you posted a 100% crop of the "noisy" spots you see we can help better
07-20-2009, 02:35 PM   #3
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QuoteOriginally posted by scorpionbowl Quote
Hello All. I've seen some excellent info on here...I've just upgraded from a K100 and have a question on a picture I took. I'm not sure what to post, but I'll start with the bright jpeg from the raw file [using photo lab, no other processing]. I'm creating an HDR, but I'm posting only the two extremes. In the fast exposure 1/2000 the darks are very dark, noise free, at ISO100, but the slow exposure 1/125 , still ISO100 looks very noisy, especially in the grass and the reflection toward the left of center. Is this noise or am I being fooled by the dew, reflections and the light fog? It has an HDR look before the processing. I'm also having a hard time with low-light focus, so that may also be an issue. The lens is a sigma 18-200 at 18mm, f3.5.

Thanks...

http://www.scorpion-bowl.com/WebHost/IMGP0476.jpg

http://www.scorpion-bowl.com/WebHost/IMGP0480.jpg
2 exposures doesn't create a very big tonal range. For HDR to be nice and crisp, you need at least 3 exposures.
07-20-2009, 04:17 PM   #4
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I don't see any noise, it just doesn't appear to be all that sharp. I'm wondering, given that your at the extreme wide end and probably wide open at that, that this lens is not up to the task of resolving sharply enough for the K20D? I'm wondering if you're not expecting too much of that lens under these wide angle/wide open conditions? I've found that even with my very good DA* 50-135mm that I need to stop down at least one stop from wide open and even stay away from f/16-22 on the other end. Trying stopping down to at least f/5.6 and compensate your exposure accordingly. Since you said you're shooting HDR, I'm assuming you're on a tripod so there should be no reason not to stop a bit and increase the exposure time a bit.

One last thing, if that one shot was your most underexposed shot, I think you could underexpose that at least another stop or two if you want more detail in the sky. The K20D of yours can do a 5-shot bracket in 2-stop increments so you might as well use them all!
And don't forget to make use of the 2 sec. self timer for a bit more sharpness (less mirror vibration).

Good luck!

Regards,
Terry

07-20-2009, 06:13 PM   #5
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Thanks guys...this was five shots by 1, I probably should have used a step by 2. It was on a tripod, with no 2-sec delay. I tried to make it quick since the fish kept jumping and disturbing the water. As mentioned, stopping down may have been best. Here's the result. Now I just need to see if it's worth buying photomatix...Thanks again...

07-20-2009, 10:22 PM   #6
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Not a bad result, me thinks...
Nice work.
07-20-2009, 10:54 PM   #7
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QuoteOriginally posted by scorpionbowl Quote
I'm also having a hard time with low-light focus, so that may also be an issue. The lens is a sigma 18-200 at 18mm, f3.5.
Are you using single center focus point? That's what I do and don't have a lot of low-light focus problems. But I also tend to have very fast glass so that helps.

I think one of the biggest problems with AF is that people use the multi-point and expect it to figure things out. I *never* use it, and instead point at what I want to focus on then recompose with the shutter held halfway down. But everyone has different needs/styles.

07-21-2009, 03:14 PM   #8
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QuoteOriginally posted by tlwyse Quote
And don't forget to make use of the 2 sec. self timer for a bit more sharpness (less mirror vibration).


Terry
The self-timer won't do anything to eliminate mirror vibration, only mirror lock-up will.
07-21-2009, 05:43 PM   #9
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QuoteOriginally posted by scorpionbowl Quote

Take this for what it's*worth--coming from someone who is waiting for his first DSLR to arrive (well, my second, from years ago), but with a lot of film experience:

It's really cool shooting into the sun, but that's not where you're going to get beautiful detail. If you had spun around 180 degrees, showing us surfaces that the lowering (or was it rising) sunlight was actually hitting, the results would have been amazing.

Know what I mean? Sun to the back of the subject will muddy everything and your camera is not recording the surfaces being directly hit by light to best effect. A great, simple explanation of photography that I heard YEARS ago, and it's as true for digital as it is for film, is that photography is all about light and surfaces.
07-21-2009, 08:01 PM   #10
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QuoteOriginally posted by Ira Quote
The self-timer won't do anything to eliminate mirror vibration, only mirror lock-up will.
I believe the two-second timer does mirror lock-up.
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