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01-21-2008, 06:53 AM   #16
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Again, you obviously DON'T know about exposure compensation, and these pictures were taken on DIFFERENT DAYS, in DIFFERENT LIGHTING CONDITIONS, with DIFFERENCE EXPOSURE SETTINGS.

QuoteQuote:
3. I know all about exposure compensation, and that it actualy means increasing ISO value, and I dont complain about that, nither about the fact that there's a certain amount of noise in pictures, I complain about the fact that since both shots were taken with the same camera, with almost idetincal lighting conditions, & almost the same in-camera settings there is such a major difference in noise level.


01-21-2008, 06:55 AM   #17
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I'm with Rickster and Gimbal on this one. You need to take some controlled test shots in good lighting and see if there is an issue or not.
Frankly I'm wondering what all the fuss is about anyway. If you crop an image to 15% of it's original size, then brighten it in PP, you'll see digital noise to some degree under the best conditions. Particularly if the shot is underexposed as the first shot appears to be.

This is pixel peeping going overboard.

Last edited by Peter Zack; 01-21-2008 at 07:02 AM.
01-21-2008, 07:41 AM   #18
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QuoteOriginally posted by egordon99 Quote
(C&P from dpreview)

This statement makes no sense and leads me to believe you are missing some fundamental understanding of photography and exposure/light.

So I URGENTLY suggest you pick up a book or two on the basics of exposure. Bryan Peterson's "Understanding Exposure" helped me get a handle on all this stuff.
I suppose I was a little too subtle when I said "remember your basic exposure lessons"! I guess some people need to be told outright!
01-21-2008, 09:33 AM   #19
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Hi Canon_S2,

I've attached a link to some of my photos also using the K10D and the Sigma 135-400mm.

Ive yet to experience the same noise levels that you have. Below is the link. The last 3 images, the seal, gull and shag were taken with the Sigma 135-400mm. I certainly don't use spot metering as a rule.

Frameless (Black) Album

01-22-2008, 03:42 AM   #20
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Original Poster
hello all again,

First of all I'd like to personally thank those who thought that my
knowladge of photography basics is so poor, that I should
immediately take a few lessons from them.

Loved the arrogant style, This would naturally promote your opinions greatly in my eyes ...
A few more facts to play with:

1. With all the thousands of shots I've taken till now (11,000 in 9 months) with my K10D, with several lenses & in most daylight conditions, the camera viewed them either in preview or in browse modes as well lighten photos on screen.

2. Furthermore studying histogram for each browsed photo shows in 90 out of 100 times that they are almost perfectly balanced by exposure & light.

3. With 1 & 2 in mind, all browsing & pps programs I'm using (like PSP12, Adobe LR 1.3, Adobe PS CS2, Elements 5.0, Adobe bridge and others) tend to show all the photos as they appear here: 3-4 steps underexposed.

I always, from day 1, had to brighten my photos to a certain degree, all of them without any exceptions, with 4 different lenses from different brands, different focal length and different aperture value.

To be more specific and absolutely understood, these 2 photos attached here as examples (Thank you David vary much for your afforts to upload them to site)

were shown by camera either in preview & also in after shot view & in standard browsing modes - as very well lighten shots & with well balanced light histogram, Explicitly not as shown here ...
Maybe this might contribute something to the on going discussion ...

And again, thank you all that took the time and tried to help ...
01-22-2008, 07:08 AM   #21
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QuoteOriginally posted by Cannon-S2 Quote
(snip) First of all I'd like to personally thank those who thought that my knowladge of photography basics is so poor, that I should immediately take a few lessons from them.

Loved the arrogant style, This would naturally promote your opinions greatly in my eyes ... (snip)

Don't get angry, my friend. Those answering are indeed trying to help, even if you don't like the answers. That (a variety of answers, not always the ones you want) is the very nature of internet forums.

Nevertheless, there is an explination for the inconsistencies. Some of those answering were close, but didn't go quite far enough. Anyway, all digital cameras have noise reduction software built-in which attempts to reduce the noise routinely generated by digital image sensors, especially at slower shutter speeds and/or higher ISO settings. However, because of even slight differences within the image itself (image detail, exposure, and so on), that software will not always process noise in the exact same way. The obvious end result is different noise levels within various images, even while the images themselves are not all that greatly different.

Still, while that might explain inconsistencies, it does not explain why some of your images are, as you put it, "very very very noisy even under excellent conditions." That has not been my experience with the camera, nor has it been a consistent issue reported by other K10D users. Here the other posters may be correct to point at exposure issues or similar factors.

Regardless, if noise is a major and ongoing concern, I suggest the application of external noise reduction software. Many have found Noise Ninja or Neat Image (my favorite) to be invaluable in these situations. Take care.

stewart
01-22-2008, 08:17 AM   #22
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QuoteOriginally posted by Cannon-S2 Quote
hello all again,

First of all I'd like to personally thank those who thought that my
knowladge of photography basics is so poor, that I should
immediately take a few lessons from them.

Loved the arrogant style, This would naturally promote your opinions greatly in my eyes ...
A few more facts to play with:

1. With all the thousands of shots I've taken till now (11,000 in 9 months) with my K10D, with several lenses & in most daylight conditions, the camera viewed them either in preview or in browse modes as well lighten photos on screen.

2. Furthermore studying histogram for each browsed photo shows in 90 out of 100 times that they are almost perfectly balanced by exposure & light.

3. With 1 & 2 in mind, all browsing & pps programs I'm using (like PSP12, Adobe LR 1.3, Adobe PS CS2, Elements 5.0, Adobe bridge and others) tend to show all the photos as they appear here: 3-4 steps underexposed.

I always, from day 1, had to brighten my photos to a certain degree, all of them without any exceptions, with 4 different lenses from different brands, different focal length and different aperture value.

To be more specific and absolutely understood, these 2 photos attached here as examples (Thank you David vary much for your afforts to upload them to site)

were shown by camera either in preview & also in after shot view & in standard browsing modes - as very well lighten shots & with well balanced light histogram, Explicitly not as shown here ...
Maybe this might contribute something to the on going discussion ...

And again, thank you all that took the time and tried to help ...
If we take what is above at face value (and note I am not prepared to do that yet) the camera has always incorrectly exposed shots from the beginning.

I find it very difficult to believe that this has gone uncorrected for 11000 shots and not been sent to pentax for service.

The next thing I have to question is, when correcting exposure and all programs show 3-4 steps under exposed, exactly what is being considered as "a step" and how is this being measured.

My experience is limited to PSP, hence I will comment as to how PSP grey scale values work.

Normal exposure by camera light meter of a uniform surface is an average value of about 125 (i.e. 50% of the grey scale value).

each stop assuming all values at 0 in the camera on JPEG (or in raw) is a change in greyscale of 45, between the range of 25 and 230. There is non linear compression of 1-2 stops below 25 and above 230.

it is IMPOSSIBLE to have 3-4 stops under exposed, because that means from 125 100% of the detail is coming out of the last 7-10 increments of grey scale! Every picture before being adjusted would be black!

Is this what you are saying??? again, I find it hard to believe that this has gone on for the life of the camera?
01-22-2008, 09:19 AM   #23
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I want to know HOW he comes up with the f-stop/shutter speed/ISO for each shot. The shots he posted say "Manual Mode" for Exposure in the EXIF. So if he's in "M", it can't be a metering issue.

I loaded his PEF into ACR and it was VERY underexposed. I pushed the "Auto" button, and it bumped the exposure slider up ~3.75 "stops", so just going by that, it might very well be 4-stops underexposed.

I also doubt that a shot like this would have a "normal" histogram when viewing it on the camera.

01-22-2008, 09:53 AM   #24
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I agree. There is something here that doesn't make sense with the underexposed shot. Cannon-S2 says that the camera has always shot this way and it's never been to service?? Also I checked the photo in my software and got the same results as egordin99. It's very underexposed. Last I checked the EXIF data in PhotoMe and it shows exposure compensation at +2Ev and shot in manual and processed on PaintShop Pro12. So this shot was taken in Manual mode, where exposure compensation does not work on the camera. The shot must have been 5-6 stops underexposed and then +2 stop increase added in PSP12. Then cropped to 15% of the original photo. (BTW the OP has changed the shot 3 times in the thread not sure why)

I'm surprised we can see anything in the shot. This smells of RH style trolling. I'm not one to normally be questioning someone I've never met but something seems odd.
01-22-2008, 10:32 AM   #25
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OK ... here's the bottom line. The 1st image was underexposed about 2 to 4 stops. If you look at the histogram nearly ALL the information are values 0 to 64.

Here is the image as shot ... (CS3 ACR)


And here is a quick recovery image from the same shot ...


Nuff said. ;-)

OH and here is the EXIF data ...
[PhotoME]
PhotoME version: 0.79 (Build 612)

[Overview]
File name: C:\Documents and Settings\Mike Jex\Desktop\IMGP0053(2).PEF
File type: Pentax Camera RAW
File size: 7,812.9 KB
Creation date: 1/15/2008 15:07
Last modification: 1/22/2008 10:20
Make: PENTAX Corporation
Camera: PENTAX K10D
Lens: Sigma 135-400 4.5-5.6 APO
Software: K10D Ver 1.30
Dimension: 3936 x 2624 px (10.3 MP, 3:2)
Focal length: 600 mm KB (400 mm Real)
Aperture: F8
Exposure time: 1/100" (+2 EV)
ISO speed rating: 125/22
Program: Not defined
Metering Mode: Spot
White Balance: User-Selected
Flash: Flash did not fire, compulsory flash mode

[Image]
Image width: 3936 px
Image height: 2624 px
Number of bits per component: 12
Compression scheme: Pentax PEF Compressed
Pixel scheme: CFA (Color Filter Matrix)
Manufacturer: PENTAX Corporation
Image input equipment model: PENTAX K10D
Image data location: 0x00014DF0
Orientation of image: 0 (top/left)
Number of components: 1
Number of rows per strip: 2624 rows
Bytes per compressed strip: 6419663 bytes
Image resolution in width direction: 72 dpi
Image resolution in height direction: 72 dpi
Image data arrangement: Chunky Format (Interleaved)
Unit of X and Y resolution: inch
Software: K10D Ver 1.30
File change date and time: 2008-01-15 15:07:20
Exif IFD Pointer: 0x00000156

[Additional Image]
Image width: 3872 px
Image height: 2592 px
Compression scheme: JPEG (old-style)
Image resolution in width direction: 72 dpi
Image resolution in height direction: 72 dpi
Unit of X and Y resolution: inch
Offset to JPEG SOI: 0x006342C0
Bytes of JPEG data: 1495284 bytes

[Camera]
Exposure time: 1/100"
F number: F8
Exposure program: Not defined
ISO speed rating: 125/22
Date and time of original data generation: 2008-01-15 15:07:20
Date and time of digital data generation: 2008-01-15 15:07:20
Exposure bias: +2 EV
Metering mode: Spot
Flash: Flash did not fire, compulsory flash mode
Lens focal length: 400 mm
Manufacturer notes: 0x000002AC
Sensing method: One-chip color area sensor
CFA pattern: [Red, Green], [Green, Blue]
Custom image processing: Normal process
Exposure mode: Manual exposure
White balance: Manual
Focal length in 35 mm film: 600 mm
Scene capture type: Standard
Contrast: Soft
Saturation: Low saturation
Sharpness: Soft
Subject distance range: Distant view

[Manufacturer notes]
Pentax Version: 30.0.0
Pentax Mode: Auto
Preview Image Size: 640 x 480
Preview Image Length: 22564 bytes
Preview Image Start: 0x00007F08
Pentax Model: K10D
Date: 2008-01-15
Time: 15:07:20
Quality: RAW
Flash Mode: Off
Focus Mode: AF-S
AF Point Selected: Fixed Center
Exposure Time: 1/100"
F Number: F8
ISO: 125
Exposure Compensation: +2
Metering Mode: Spot
Auto Bracketing: 0 EV
White Balance: Daylight
White Balance Mode: User-Selected
Focal Length: 400 mm
Saturation: Med Low
Constrast: Very Low
Sharpness: Med Soft
World Time Location: Destination
Hometown City: Jerusalem
Destination City: Jerusalem
Hometown DST: Yes
Destination DST: Yes
??? (0027): <Binary Data>
??? (0028): <Binary Data>
??? (002D): 14592
Picture Mode: Shutter & Aperture Priority AE (1)
Drive Mode: Continuous
??? (0035): 11894, 7962
Color Space: sRGB
Image Area Offset: x = 8, y = 8
Raw Image Size: width = 3872, height = 2592
??? (003D): 8192
??? (003E): 26, 26, 0, 0
Lens Type: SIGMA
Camera Temperature: 13 C
??? (0048): 0
Noise Reduction: Off
Red Balance: +0.3
Image Tone: Natural
??? (0050): 0
??? (0053): <Binary Data>
??? (0054): <Binary Data>
??? (0055): <Binary Data>
??? (0056): <Binary Data>
??? (0057): <Binary Data>
??? (0058): <Binary Data>
??? (0059): <Binary Data>
??? (005A): <Binary Data>
SR Result: stabilized
Shake Reduction (Setup): On
Photometering To Release Switch Time: 89
SR Focal length: 404 mm
Shutter Count: 10699
??? (0062): 1
BlackPoint: [0, 0, 0, 0]
WhitePoint: [13600, 8192, 8192, 8736]
??? (0205): <Binary Data>
AE Info: <Binary Data>
AE Exposure Time: 1/93.1"
AE Aperture: F8
AE ISO: 130
AE Xv: -2 Ev
AEB Xv: 0 Ev
AE Flash Tv: Not available
AE Program Mode: Manual/Program AE
AE Extra: 0
Lens Info: <Binary Data>
Lens Type: Sigma 135-400 4.5-5.6 APO
Lens Kind / Version (LC0): 2 / 8
Lens Data (LC1): 148
Distance Code Data (LC2): 132
K-Value (LC3): 160
Near Distance Abberation Correction Data (LC4): 86
Light Color Abberation Correction Data (LC5): 6
Open Abberation Data (LC6): 227
AF Minimum Actuation Condition Data (LC7): 65
Focal Length Data (LC8): 162
Nominal AVmin / AVmax Data (LC9): 171
mv' nv' Data (LC10): 64
AVC 1/EXP Data (LC11): 48
mv1 Avminsif Data (LC12): 1
AVmin Data (LC13): 81 (F5.7)
UNT_12 UNT_6 Data (LC14): 107
Incorporated Flash Suited Data (LC15): 251
Flash Info: <Binary Data>
Flash Status: 0
Flash Mode Code: Off (240)
External Flash Mode: 63
Internal Flash Magnitude: 0
TTL D/A A-ch Up: 0
TTL D/A A-ch Down: 0
TTL D/A B-ch Up: 0
TTL D/A B-ch Down: 0
AE Metering Segment 1: ~7.9 LV (center)
AE Metering Segment 2: ~7.8 LV (center edge)
AE Metering Segment 3: ~7.4 LV (upper, mid-right)
AE Metering Segment 4: ~6.9 LV (upper, mid-left)
AE Metering Segment 5: ~8.5 LV (upper, right)
AE Metering Segment 6: ~7.6 LV (upper, left)
AE Metering Segment 7: ~7.9 LV (mid-right)
AE Metering Segment 8: ~7.5 LV (mid-left)
AE Metering Segment 9: ~9.1 LV (right)
AE Metering Segment 10: ~8 LV (left)
AE Metering Segment 11: ~8.8 LV (lower, mid-right)
AE Metering Segment 12: ~7.9 LV (lower, mid-left)
AE Metering Segment 13: ~8.6 LV (lower, right)
AE Metering Segment 14: ~8.3 LV (lower, left)
AE Metering Segment 15: ~8 LV (top)
AE Metering Segment 16: ~8.9 LV (bottom)
Flash A Dump: <Binary Data>
Flash B Dump: <Binary Data>
WB RGGB Levels Daylight: [13600, 8192, 8192, 8765]
WB RGGB Levels Shade: [16128, 8192, 8192, 6635]
WB RGGB Levels Cloudy: [14560, 8192, 8192, 7782]
WB RGGB Levels Tungsten: [8192, 8192, 8192, 20971]
WB RGGB Levels Fluorescent D: [17376, 8192, 8192, 8847]
WB RGGB Levels Fluorescent N: [14528, 8192, 8192, 10076]
WB RGGB Levels Fluorescent W: [13088, 8192, 8192, 12206]
WB RGGB Levels Flash: [13632, 8192, 8192, 8601]
Pentax Model: K10D
Manufacture Date: 20070119
Model Revision: 1.1
Internal Serial Number: 3840752
Battery Kind: 2
Body/Grip State Level: Body: 4, Grip: 1
Battery A/D Body No Load: 172 (7.6V, 52%)
Battery A/D Body Load: 168 (7.4V, 50%)
Battery A/D Grip No Load: 5
Battery A/D Grip Load: 1
??? (021A): <Binary Data>
??? (021B): <Binary Data>
??? (021C): <Binary Data>
??? (021D): <Binary Data>
??? (021E): <Binary Data>
AF Info: <Binary Data>
AF Points...?: 238
AF Point In Focus: Center (vertical)
??? (0220): <Binary Data>
??? (0221): <Binary Data>
??? (0222): <Binary Data>
??? (0223): <Binary Data>
??? (0224): <Binary Data>
??? (03FF): <Binary Data>
??? (0404): <Binary Data>
??? (0405): <Binary Data>

Last edited by Rickster; 01-22-2008 at 10:44 AM.
01-22-2008, 10:37 AM   #26
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I got about the same result using ACR to fix it up last night. Doesn't look too bad for a small web-sized shot. Should make a nice 5x7.

OP - What MODE (on the mode-dial on the camera body) do you use? Are you in Manual mode? How did you arrive at 1/100s, f/8, ISO125?
01-22-2008, 10:47 AM   #27
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QuoteOriginally posted by egordon99 Quote
I got about the same result using ACR to fix it up last night. Doesn't look too bad for a small web-sized shot. Should make a nice 5x7.

OP - What MODE (on the mode-dial on the camera body) do you use? Are you in Manual mode? How did you arrive at 1/100s, f/8, ISO125?
He was in manual mode according to the EXIF data above.
01-22-2008, 10:51 AM   #28
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That's what I thought, but wanted confirmation. I'm still scratching my head over this entire episode.

I think the OP thought he could just dial in any aperture/shutter speed he wants, keep the ISO at 100/125 (for low noise ) and then just use "Exposure Compensation" in the computer. He only gets concerned when he notices that shots on non-identical days with non-identical settings in non-identical lighting conditions yield different amounts of noise after pushing the shots upwards of 4 stops. Oh, and he doesn't know how to read the in-camera histogram.

I'm with Peter above, something doesn't sound right....

That's my story and I'm sticking to it
01-22-2008, 11:04 AM   #29
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Just what I thought, shots look pretty black before pp.

I note ISO 125, f8 1/100 sec,

this speed etc should be for a bright high overcast day, away from shadows.

anyway, recovered photo does not clean up too bad, given the starting point.

I stand by my comment also, if the in camera exposure meter actually thought this was the correct exposure, I would have taken the camera back a long time ago
01-22-2008, 03:52 PM   #30
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QuoteOriginally posted by Lowell Goudge Quote
Just what I thought, shots look pretty black before pp.

I note ISO 125, f8 1/100 sec,

this speed etc should be for a bright high overcast day, away from shadows.

anyway, recovered photo does not clean up too bad, given the starting point.

I stand by my comment also, if the in camera exposure meter actually thought this was the correct exposure, I would have taken the camera back a long time ago
I think the camera thought it was 2 stops underexposed according to the EXIF info. See the red highlighted text above.

The camera reported LV values from 6.9 to 9.1 that would give a lighting of LV ~7-8 ... Typical indoors; light outdoors about 10 minutes after sunset. I.E. not very bright. According to my calculations ( 7 stops less exposure than 1 sec at f/1.0 Iso 100 ) the exposure should have been .5 to 1 seconds at F/8.0 not 1/100 second.

Last edited by Rickster; 01-22-2008 at 04:04 PM.
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