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10-20-2010, 09:55 AM   #1
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High Noise at Low ISO?

I've bought a K-7 from someone on the marketplace, it's in great shape, but I'm finding I get what looks to me like a lot of noise at all ISO settings, incl 100, my optio never produced this much noise below ISO 400.
I tried resetting to factory defaults, seem to still be not quite sharp focused with AF, when I zoom to 100%, I see a lot of blurriness even where it should be sharp.

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10-20-2010, 09:59 AM   #2
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That's not noise- those are JPEG artifacts likely caused due to in-camera sharpening. Try checking the RAW file to judge noise.

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10-20-2010, 05:20 PM   #3
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Your shutter speed also looks low.
11-05-2010, 10:23 PM   #4
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My shutter speed was low to get that low ISO, and so I could show the noise I am seeing without a distracting image. The noise is still there in the 2nd image but much less apparent.
Is it still possible to see the EXIF data on these images?

I thought I had disabled all in camera sharpening, by pushing the right hand button, and turning down all the settings below contrast.

how can I turn this all off? All my images are shot in Jpeg, and these artifacts or noise are really irritating me in a lot of pictures.
Ideally I'd prefer to have nothing happen in the camera, get the best quality base image I can and do any correction or editing in Lightroom/PS if I have to.

11-05-2010, 11:38 PM   #5
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QuoteOriginally posted by JGB Quote
Ideally I'd prefer to have nothing happen in the camera, get the best quality base image I can and do any correction or editing in Lightroom/PS if I have to.
Then shoot raw.
11-06-2010, 12:53 PM   #6
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QuoteOriginally posted by JGB Quote
Ideally I'd prefer to have nothing happen in the camera, get the best quality base image I can and do any correction or editing in Lightroom/PS if I have to.
You've just described RAW.
11-06-2010, 01:18 PM   #7
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Your Optio probably did a lot of smoothing and noise reduction behind the scenes, at the expense of detail You will see a lot less grain / artefacts if you process RAW. If you have to use JPEG only, make sure the shadow correction is off, because that can increase shadow noise!

Remember when you are viewing images at 100% that a print at that size would be 4.6 x 3.1m - about the size of a parking space. You aren't going to see this on an A3 or A2 print


Last edited by ihasa; 11-06-2010 at 01:26 PM.
11-06-2010, 02:29 PM   #8
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...If you're interested, the 100% crop below is from an ISO800 shot, with the out-of-camera kpeg on the left, and the processed RAW file on the right. Yes I applied a little NR in Lightroom, but both are pretty clean really IMO

11-06-2010, 03:17 PM   #9
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Sadly I can't afford to shoot raw.
How do I disable the in camera sharpening, or at least minimize any alterations

I'm riding a motorbike to Argentina, there will be a lot of photos, and RAW would take more than I can spare. So I'm looking to get the best possible JPEG.
I'm shooting for school(photo student) so I may be printing fairly large.

Is there a recommended set of settings to minimize the appearance of these things without going to RAW?(I disabled shadow and highlight correction right off the bat.)


Does that amount of noise or artifacts look normal? I find it a bit of a problem for cropping. I turned off every noise reduction setting I could find, we'll see if that helps.
My optio didn't really do much more smoothing etc once I changed the settings in it. at least at low ISO I got nice results, I got the same look I see in the K7 above that though.

I have the Noise Ninja plugin, but haven't got around to figuring out how to use it yet.
If I do shoot raw, what format should I end up using? And where would the benefits of RAW really shine through?(low light?) I could potentially use it sparingly for some shots, but certainly not more than 1 or two shots a day, out of the 50 or so I shoot in a day.
11-06-2010, 05:25 PM   #10
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When shooting Jpeg, shoot with natural setting. Set your sharpening to -1 and set your noise reduction to weak. Sharpening in the K7 really has a tendency to add a lot of artifacts and noise to otherwise decent images. You can always sharpen them a little later if you need to.

As to RAW formats, they are equivalent. DNG is more widely used, but PEFs are read fine by Adobe. In the past, DNGs were not compressed and so they were big compared to the PEF files, but I think they are pretty close to the same size on the K7.

I would get some more memory cards at some point. With the price of flash memory what it is, that is one thing you shouldn't run short on. In the United States, a 16 gig card will run 35 to 40 dollars.
11-06-2010, 05:28 PM   #11
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My optio didn't really do much more smoothing etc once I changed the settings in it. at least at low ISO I got nice results, I got the same look I see in the K7 above that though.

Compact cameras are designed to process the image without you having to do anything.

I have the Noise Ninja plugin, but haven't got around to figuring out how to use it yet.

Well learn it then, photography student! Actually Photoshop has a good enough noise reduction filter for minor noise control. Noise Ninja's for 'rescuing' high ISO shots which isn't quite what you are doing here....

Have you tried enabling High ISO NR to kick in at ISO 200? That might help if you are addicted to pixel peeping! You can adjust the level of in camera NR.

If I do shoot raw, what format should I end up using? And where would the benefits of RAW really shine through?(low light?) I could potentially use it sparingly for some shots, but certainly not more than 1 or two shots a day, out of the 50 or so I shoot in a day.

You can choose PEF or DNG format. DNG is an open format which any RAW converter can handle. PEF is Pentax's own proprietary format, but by now most if not all RAW converters accept K-7 PEFs. And PEF files are fractionally smaller.

The benefits of RAW shine through wherever you want to tweak the image without degrading quality, and yes particularly in low light/high ISO. If you shoot jpeg the camera ALWAYS processes the image, you can't turn this image processing off - it is required in order to output a jpeg file from the data gathered by the sensor. So if you want the camera to stop 'doing stuff' to the image, you are going to have to shoot RAW.

One solution would be to shoot RAW+Jpeg but systematically delete all the 'junk' shots at the end of each day, and delete the RAW shots but leave the jpeg behind where the shot is worth keeping but unlikely to be one of your more important images. Oh and take lots of memory cards.
11-07-2010, 02:06 AM   #12
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QuoteOriginally posted by Rondec Quote
When shooting Jpeg, shoot with natural setting. Set your sharpening to -1 and set your noise reduction to weak. Sharpening in the K7 really has a tendency to add a lot of artifacts and noise to otherwise decent images. You can always sharpen them a little later if you need to.

As to RAW formats, they are equivalent. DNG is more widely used, but PEFs are read fine by Adobe. In the past, DNGs were not compressed and so they were big compared to the PEF files, but I think they are pretty close to the same size on the K7.

I would get some more memory cards at some point. With the price of flash memory what it is, that is one thing you shouldn't run short on. In the United States, a 16 gig card will run 35 to 40 dollars.
I will try to pick some up, I'm on a rather tight budget though, the motorbike only cost me 50$ to start, but 1500$ later the rebuild is just about done with me back on the road, unfortunately, that was a huge chunk of my trip budget, combine that with buying a K-7 and one more lens, some cards(2 4gb sandisk extreme III from amazon), a tripod and knock off battery grip, and a few other odds and ends and I'm looking at the better part of 3000$, over half budget for the next 8 months.

Also, enough cards for 8 months is a lot! I have a laptop I'll be downloading to, but there are risks of losing it and so forth too.


QuoteOriginally posted by ihasa Quote
My optio didn't really do much more smoothing etc once I changed the settings in it. at least at low ISO I got nice results, I got the same look I see in the K7 above that though.

Compact cameras are designed to process the image without you having to do anything.

I have the Noise Ninja plugin, but haven't got around to figuring out how to use it yet.

Well learn it then, photography student! Actually Photoshop has a good enough noise reduction filter for minor noise control. Noise Ninja's for 'rescuing' high ISO shots which isn't quite what you are doing here....

Have you tried enabling High ISO NR to kick in at ISO 200? That might help if you are addicted to pixel peeping! You can adjust the level of in camera NR.

If I do shoot raw, what format should I end up using? And where would the benefits of RAW really shine through?(low light?) I could potentially use it sparingly for some shots, but certainly not more than 1 or two shots a day, out of the 50 or so I shoot in a day.

You can choose PEF or DNG format. DNG is an open format which any RAW converter can handle. PEF is Pentax's own proprietary format, but by now most if not all RAW converters accept K-7 PEFs. And PEF files are fractionally smaller.

The benefits of RAW shine through wherever you want to tweak the image without degrading quality, and yes particularly in low light/high ISO. If you shoot jpeg the camera ALWAYS processes the image, you can't turn this image processing off - it is required in order to output a jpeg file from the data gathered by the sensor. So if you want the camera to stop 'doing stuff' to the image, you are going to have to shoot RAW.

One solution would be to shoot RAW+Jpeg but systematically delete all the 'junk' shots at the end of each day, and delete the RAW shots but leave the jpeg behind where the shot is worth keeping but unlikely to be one of your more important images. Oh and take lots of memory cards.
The thing is that even with photoshop I can't seem to get those artefacts, or noise down to a level equal to the optio and keep the same level of detail at the same ISO, surely a high end program should do a better job than 4 year old in camera image processing technology? I turned it down on that camera as much as possible. I don't mind what the camera does to the image to a certain extent, I'd just like to minimize the negative effects like those seen here or what you get with highlight and shadow fixing turned on.
Between learning to build a motorcycle, sorting out my equipment, trying to learn spanish, and whatever skills I'll need south of the border, keeping my coursework for two classes up to date(I'm in 2 online classes, and this trip counts as self directed study so my student loans don't come and haunt me) learning wordpress, coppermine photo gallery, lightroom 3 and photoshop, to shoot a a K-7 and automatic lens instead of a P&S or all manual OM-1, write a blog and keep my trip report up to date with both my family and 4 forums, answer all the questions on each, Noise Ninja is just gonna have to wait.

Does the High ISO NR actually help with what I'm seeing in that image? Is there an easy way to duplicate it's settings in software, so I can try shots with and without it in post processing?

I think at this point, I'll push the Raw button, and leave it set to Raw+ when I know the lighting is bad, or I'm looking at an amazing potential shot.

In the in camera menu's what should I turn off to reduce the camera's modification of the JPEG, or what should I leave on, if there are settings that are worth keeping because they work well in most situations?

Also, what is the difference between sharpness, fine sharpness, fine 2 sharpness?
When I turn down sharpness, it doesn't give me a number, is -1 all the way over to the left, or just one button press from the center green bar in the menu?
are any of the other settings worth turning down?

Last edited by JGB; 11-07-2010 at 02:29 AM.
11-07-2010, 05:34 AM   #13
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I would move the sharpness and fine sharpness one click to the left and see how you like that setting. I understand a budget and you have to spend what you can afford. I guess I would get a bigger card and then down load them every night to your lap top. Then, if you have internet access, up load them to a server where they can be stored as a back up. Nothing is fail safe -- certainly not lap top hard drives or SD Cards.

I have the noise reduction on jpeg set to low and to begin at iso 800. Noise ninja will work well with your K7, although it will take some experimenting to get the best results from it. Depending on your lap top speed, it may require quite a bit of time to run however.

Just to mention with regard to blurriness. Do a couple of tests using a tripod. It could be this issues are more camera shake. That is what it looks like to me. Macro shots are really hard to do hand held, even with decent shutter speed.

Keep working and things will turn out great!
11-08-2010, 02:26 AM   #14
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Ok, which would you use, fine or regular sharpness since I have to pick between the two? What about -3 and sharpen in post processing if needed.
I like the look ofthe Jpegs for the most part I'm just trying to minimize any downsides for printing up to about A4 or so.

For low light I will use Raw.
I found this interesting link that lets you compare the sharpness settings live.

Pentax K-7 Sharpness Settings | Neocamera


Also, what about the contrast high low adj and all the other settings, any recommendations there?
11-08-2010, 05:46 AM   #15
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I would turn down fine sharpness and then as you say, sharpen in post as you need to. I have found the rest of the settings with the natural setting to be pretty good/. Bright is probably OK with low iso/ landscape photos, but it tends to do funny things to skin tones. I guess it bumps up the saturation/vibrance a little too much.

One thing to remember is that you can play around with these things if you have the Pentax photo developer software. It will let you apply different settings to RAW files and see the results. Might be interesting to try and see what things you like and don't like.
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