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09-21-2010, 09:05 PM   #1
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Picture noisy at 100% size.

I have a k20D and recently the pictures look a bit more noisy than usual , esp when I zoom to 100% (sample attached)..I tried different lenses ( including a brand new one) , but still same problem exists... I am still new to SLR photography and am not sure if this is because of a faulty focus/setting or if something be wrong with my camera...

Also, if you look at the separation between the black pant and the sky, the edges seem to be fading, not sure if this is normal at 100% zoom

This pic was taken using a Tamron 70-300mm lens, but I have similar problem even with Pentax 18-55 and 50mm 1.4 lens.. Please advice.

Photo Specs:
ISO : 200
f 6.7, 300mm
exposure time : 1/750 sec

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09-21-2010, 09:53 PM   #2
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Did you really mean noisy, or is it blurred?

As for noise, it's normal with high ISO settings. This is not the case with this picture as it's shot with ISO 200 and looks perfectly fine regarding noise considering you own a K20D.

On the other hand, the picture is blurred, and I'm not sure if it was simply out of focus or if it's motion blur because the guy is on a plane and I don't know if it was moving or not. Looks more like out of focus for me.

Before saying the camera is faulty, it helps paying attention on how you're focusing. Here's a checklist:

- Were you using Auto 11, 5 or center focus?
- Did you confirmed the right focus point was selected for the given composition?
- Did you waited the camera to confirm focus (VF light or beep) before hitting the shutter?
- If it was shot handheld, did you awaited SR to activate (it takes around 0.5s from when you press shutter halfway, and lights up SR icon on VF)?
- Did you shot using the viewfinder or the live view (be aware live view focusing is slower, and the way you handle the camera is less stable)?

I don't know anything about the IQ of this Tamrom 70-300, but consider that when shooting on the long-tele range (300m or more) you can benefit from bigger apertures than f/6.7 for faster shutter speeds, although 1/750s isn't any bad for handheld. My bet is that you were using Auto 11 and the camera focused somewhere else (and I can't see because you cropped the pic), or you didn't waited it to acquire focus.

We can help better if you post a different picture with a static subject that came out of focus though, can't be sure if this plane was moving or not.

Last edited by hcarvalhoalves; 09-21-2010 at 11:07 PM.
09-21-2010, 10:00 PM   #3
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It looks like vibration, if the airplane isn't moving then it still looks the engine is turning!!!
- Can you add 100% crop of more stable area of airplane in front of guy and behind the guy? (that will in-/exclade out of focus)

Last edited by JoepLX3; 09-21-2010 at 10:03 PM. Reason: typo
09-21-2010, 10:01 PM   #4
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Yeah, looks out of focus to me.

09-21-2010, 10:58 PM   #5
pbo
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You'll get noise in shadows even at low ISO's - that's normal. Basically, if this picture was brighter, I'd bet there would be less noise
09-22-2010, 04:20 AM   #6
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QuoteOriginally posted by kulkarni_1980 Quote
"Also, if you look at the separation between the black pant and the sky, the edges seem to be fading, not sure if this is normal at 100% zoom"

This pic was taken using a Tamron 70-300mm lens, but I have similar problem even with Pentax 18-55 and 50mm 1.4 lens.. Please advice.

Photo Specs:
ISO : 200
f 6.7, 300mm
exposure time : 1/750 sec
I am not sure if when you say you have a similar problem with the other two lenses you are refering to the "edges fading" only or the blur or both?
If it is the blur as well have you tried a shot tripod mounted , 12 second delay to avoid shake in the tripod and looked at the results?
It looks from your images supplied like camera shake as far as the blur is concerned. The speed is fast enough to hide vibration from the plane I would have thought. As far as the edges I suspect that is due to the blur at that magnification.
adwb
09-22-2010, 04:50 AM   #7
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What is the rpm of a propeller?
- Googling resulted in 1-2000 during taxi-ing + 60 s in 1 minute --> 1800/60=300 rps
- Potentially 1/175 s might not have been enough...
09-22-2010, 08:19 AM   #8
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QuoteOriginally posted by JoepLX3 Quote
What is the rpm of a propeller?
- Googling resulted in 1-2000 during taxi-ing + 60 s in 1 minute --> 1800/60=300 rps
- Potentially 1/175 s might not have been enough...
Agreed, I was thinking more of the inevitable vibration and therefore movement that you would not see with the engine running, for that I would have thought that the shutter speed quoted was adequate.
adwb

09-22-2010, 08:33 AM   #9
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Oh, I am not sure it is shutter yet... (just a theory to be confirmed or proven to be wrong)
- I am looking forward to some 100% of other parts of the plane, closer to frame, that vibrate less as well as more to back and front (to check overall focus impact)

Also interesting to know how shot was taken, with tripod or hand hold at 300 mm
- And are same problems on other lenses, as in noise at airplane pictures only...
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