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05-10-2008, 08:30 PM   #1
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K20d Image Question

Greetings to all:

In just my second thread here I hope to pick the brains of any of you who are able and willing to provide me with some direction. About a month ago I purchased the K20d and have been working diligently with it since then. Being my first DSLR, the learning curve is more pronounced than it must be for many.

I am here now because, while wandering the web for 2 months seeking wisdom on DSLRs, I often happened upon this neat little place. And my previous visits here have been fruitful which, for better or worse, slowly but surely, helped to sway me to the so-called "Pentaxian" view of the photographic universe. However, I must admit, I was not hoping to be here this early into my ownership of the K20d with an SOS.

But I am here. I recently went out to try shooting running water in a practice attempt to seize the neat effects of slow shutter speed upon moving water. Towards this end, I picked up a 49mm ND8x Hoya filter for the M 1.7 and went over to a local run-off to try things out. Now a run-off into a river is hardly picturesque, but itís the closest thing to a waterfall I have in the immediate vicinity. Not only was I learning the new K20, but I was also performing the Zen balancing act called metering an M lens by all you indoctrinated Pentaxians, while also trying out the vagaries of the ND8x. Need I mention the art of manual focusing this so-called high performing M lens? I took some shots and went home to see what I could see. When I got home and plugged the SD card into the PC, I had surprises. They were not pleasant ones either. No, the fact that many of the shots were terribly over-exposed did not bother me; I know this metering an M lens thing will take much hoop jumping to perfect. What bothered me was on some of the images there was a little c-shaped oddity just down and left of center. I also noticed this only seemed to appear on long exposures--3 to 8 secs. And I noticed it only appeared on this day's images because the oddity happens to line up in a light and evenly colored water background which the river provided.

It took me a couple of days to investigate it, but today I did seek understanding. Of course I tried to duplicate the oddity, but indoors this time and without the Hoya ND8--the oddity is still there, in the same spot. Simple enough, I changed from the M 1.7 to the 85mm 1.8., shot long exposures in very low light, and learned the oddity was, again, still there staring at me. Although I should mention, it does not seem as defined on the 85mm, but it is definitely there. So using simple logic, I deduced, Da (pun-intended), inside the camera there must be something foreign--but why and how--the camera still has new-camera smell if you know what I mean. With the care of a surgeon, I removed the lens, peered inside and blew with all my might. Oh, should have mentioned, I did the silly little shake the sensor clean dance (aka High tech Dust Reduction) before all this with no success too.

The mirror looked clean, before and after my cleansing efforts--but more shooting revealed the problem was not solved. So I concluded there must be a substance on the mirror, or on something. Not being a plastic surgeon, and fearing a possible mishap while trying to swab the mirror, I, nonetheless, grabbed my baby's-bottomed soft lens camera cloth and ever so gently swabbed the mirror. Again, I had no success. It looks like the problem is elsewhere, or else the mirror has an invisible stain which generates this oddity only at certain long exposures.

Now, of course in % 98 of my shooting the oddity poses no problem because it will simply be absorbed into the background without notice; in fact its presence had evaded me for over three weeks. However, I took the leap into DSLR land, along with $2000, and have problems already that my little bitty Canon S3 never saw even though it hiked through the mountains of the eastern US with me for years, sometimes in temps below zero (Jan @ 5000ft in Maine and NH). Not that, obviously, I expect the K20 to take a beating in a backpack like the S3 did, never uttering a single objection to anything I threw at it. But I sure as heck did not expect this problem from a camera in this class, which has been handled with the care of a new born--the first-born for that matter!!!

Does anyone have any help?

Best Regards,

Ernest

05-10-2008, 08:56 PM   #2
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QuoteOriginally posted by Jewelltrail Quote
Greetings to all:

In just my second thread here I hope to pick the brains of any of you who are able and willing to provide me with some direction. About a month ago I purchased the K20d and have been working diligently with it since then. Being my first DSLR, the learning curve is more pronounced than it must be for many.

I am here now because, while wandering the web for 2 months seeking wisdom on DSLRs, I often happened upon this neat little place. And my previous visits here have been fruitful which, for better or worse, slowly but surely, helped to sway me to the so-called "Pentaxian" view of the photographic universe. However, I must admit, I was not hoping to be here this early into my ownership of the K20d with an SOS.

But I am here. I recently went out to try shooting running water in a practice attempt to seize the neat effects of slow shutter speed upon moving water. Towards this end, I picked up a 49mm ND8x Hoya filter for the M 1.7 and went over to a local run-off to try things out. Now a run-off into a river is hardly picturesque, but itís the closest thing to a waterfall I have in the immediate vicinity. Not only was I learning the new K20, but I was also performing the Zen balancing act called metering an M lens by all you indoctrinated Pentaxians, while also trying out the vagaries of the ND8x. Need I mention the art of manual focusing this so-called high performing M lens? I took some shots and went home to see what I could see. When I got home and plugged the SD card into the PC, I had surprises. They were not pleasant ones either. No, the fact that many of the shots were terribly over-exposed did not bother me; I know this metering an M lens thing will take much hoop jumping to perfect. What bothered me was on some of the images there was a little c-shaped oddity just down and left of center. I also noticed this only seemed to appear on long exposures--3 to 8 secs. And I noticed it only appeared on this day's images because the oddity happens to line up in a light and evenly colored water background which the river provided.

It took me a couple of days to investigate it, but today I did seek understanding. Of course I tried to duplicate the oddity, but indoors this time and without the Hoya ND8--the oddity is still there, in the same spot. Simple enough, I changed from the M 1.7 to the 85mm 1.8., shot long exposures in very low light, and learned the oddity was, again, still there staring at me. Although I should mention, it does not seem as defined on the 85mm, but it is definitely there. So using simple logic, I deduced, Da (pun-intended), inside the camera there must be something foreign--but why and how--the camera still has new-camera smell if you know what I mean. With the care of a surgeon, I removed the lens, peered inside and blew with all my might. Oh, should have mentioned, I did the silly little shake the sensor clean dance (aka High tech Dust Reduction) before all this with no success too.

The mirror looked clean, before and after my cleansing efforts--but more shooting revealed the problem was not solved. So I concluded there must be a substance on the mirror, or on something. Not being a plastic surgeon, and fearing a possible mishap while trying to swab the mirror, I, nonetheless, grabbed my baby's-bottomed soft lens camera cloth and ever so gently swabbed the mirror. Again, I had no success. It looks like the problem is elsewhere, or else the mirror has an invisible stain which generates this oddity only at certain long exposures.

Now, of course in % 98 of my shooting the oddity poses no problem because it will simply be absorbed into the background without notice; in fact its presence had evaded me for over three weeks. However, I took the leap into DSLR land, along with $2000, and have problems already that my little bitty Canon S3 never saw even though it hiked through the mountains of the eastern US with me for years, sometimes in temps below zero (Jan @ 5000ft in Maine and NH). Not that, obviously, I expect the K20 to take a beating in a backpack like the S3 did, never uttering a single objection to anything I threw at it. But I sure as heck did not expect this problem from a camera in this class, which has been handled with the care of a new born--the first-born for that matter!!!

Does anyone have any help?

Best Regards,

Ernest
It would seem that you have something foreign attached to your sensor. If it were on the mirror, you could detect it in the viewfinder, but it would not appear on the images.

Ergo, you are blowing out the wrong area of the camera. First of all, do not blow with your breath - this can humidify the innards to bad effect. At your local shop, get yourself a lens blower - a very popular one is the "Rocket Blower" which looks just like a rocket, but costs not all that much.

Once you have the proper tool (and not canned air, it must be a hand squeezed blower) , you can attempt to clean the sensor.
  1. Remove the lens from the camera.
  2. In the menus, find the cleaning function - in my K10D it is found in the Set-up menu, identified by a wrench icon.
  3. Select [Sensor Cleaning] and press the four-way controller to the right
  4. Press the four-way controller up to select [Mirror Up]
  5. Press [OK]
  6. I now turn the camera so the mount faces down, on the perhaps foolish thought that the dust will fall out, and use the blower to gently blow into the camera.
  7. Turn the camera off to end the cleaning mode.
  8. Attach the lens and try a shot to see if you were successful.
There are kits one can purchase to clean the sensor. Use them with extreme care to prevent damage to the sensor.

I hope this helps you resolve your interesting little artifact.

PS - welcome to the world of Pentax!
05-10-2008, 09:48 PM   #3
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Welcome to the black art of cleaning sensors. First == before you do anything go here and read everything on this site:
Cleaning Digital Cameras - Introduction
It is a good place to start.

As for me, I have not had to clean my K10D since I bought it. My *ist Ds was getting a cleaning before I left the house. I usually change lenses a few times during an outing, so dust is an issue.

Get a Rocket Blower and you should be good, unless you are one of those who just has to clean. Although you might be one of those poor individuals who live in really dusty environments and need to monitor dust on a regular basis. Just clean everything before you go out - including the rear lens elements and all lens caps.

The Elitist - formerly known as PDL
05-10-2008, 10:31 PM   #4
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To Canada Rockies and PDL----THANK YOU! I feel much better, or did for a few seconds after reading this. Then I ran into the post on Hot Pixels. It appears as if I may have that too. I left an image in that post, but the file size was reduced too drastically to see the hot pixel. However, the c-shaped oddity is clearly visible in that link.

It looks like I should have bought the 40d or A700! I may become a regular here.


Regards,

Ernest

05-11-2008, 06:43 AM   #5
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QuoteOriginally posted by Jewelltrail Quote
It looks like I should have bought the 40d or A700!
Because of this? Dust can get on any sensor?
05-11-2008, 07:13 AM   #6
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If you buy a sensor cleaning kit, make sure it is COMPATIBLE WITH THE COATING ON THE K20D SENSOR, as some might damage it. The coating on the sensor might be damaged by some chemical cleaner. Don't ask how I know that. The camera is not back from the repair shop yet (should have it by Monday or Tuesday).
05-11-2008, 09:40 AM   #7
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Because of this? Dust can get on any sensor?


Mattdm:

No, not just because I have a major blob of dust on a brand new camera. I also learned the camera, see other post, has "hot pixel" issues as well. But that is not the end--I also spent an hour with Pentax CS in Colorado, on phone, on another issue which came up in first days of ownership.

Believe me, I want to believ in the K20--it has many things I am looking for--it is rugged and I hike a lot. It has image stabilization in the body--I personally see this as better than lens stabilization. It also has a much better backward lens compatibility setup. But if I keep encountering issues, I will surely lose my enthusiasm for the camera. This is my first DSLR--i had high hopes for it--but I do not think they were too high.

Bes Regards,

Ernest
05-11-2008, 04:08 PM   #8
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I followed the advice so kindly given here and it looks like whatever was on the sensor is gone--thank you to everyone contributing to my success!

Best regards.

Ernest

05-13-2008, 09:56 PM   #9
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[QUOTE=Jewelltrail;239756]Greetings to all:

<snip>
But I am here. I recently went out to try shooting running water in a practice attempt to seize the neat effects of slow shutter speed upon moving water. Towards this end, I picked up a 49mm ND8x Hoya filter for the M 1.7 and went over to a local run-off to try things out. Now a run-off into a river is hardly picturesque, but itís the closest thing to a waterfall I have in the immediate vicinity.
<snip>

Ernest - Just a tip that could save you a lot of hassle trying to achieve the "smooth water" long exposure results with your K series camera. In the Recording menu, you will find the Multi-exposure mode. Selecting that you have an option to set how many frames you would like to expose, and also you can select to have the frames exposure averaged between the number of frames you selected. This is done by "checking" the Auto EV option. Take a test shot to nail the exposure first, set the camera to take pictures at the proper settings, then set up multi-exposure with auto EV. You will be surprised at the smooth water effect you can achieve with 9 frames. The high resolution of the K20D especially gives a view camera like result with no neutral density filters to pack around. The Auto EV option combines all the moving parts of the individual frames but averages out all the exposures.

Note that if you do not select Auto EV then the multi-exposure sequence will be additive as with the standard stacking effect where each exposure adds to the next with no averaging of exposures. This is a way to avoid the low signal/high noise fact of the K20D's CMOS sensor: if you take a longer series of shorter exposures it will minimize the noise for the total length of the exposure. In short: Auto EV for water; traditional stacking for astrophotography.
05-13-2008, 10:49 PM   #10
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QuoteOriginally posted by Jewelltrail Quote
Because of this? Dust can get on any sensor?


Mattdm:

No, not just because I have a major blob of dust on a brand new camera. I also learned the camera, see other post, has "hot pixel" issues as well.

Bes Regards,

Ernest
A friend of mine bought a brand new Canon 20D a few years back and got it complete with a stack of dust on the sensor. Its not a Pentax thing, its a manufacturing thing.

And there is no hot pixel issue on the K20D. If there is, its equally applicable to all cameras, since they all have it. Thats a pixel technology thing.
05-13-2008, 11:14 PM   #11
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Look at the Dust Alert feature to see exactly what is on your sensor. There is a simple procedure to snap a view as to what if anything is clinging to your sensor. This feature is exclusive to the K20D.

Page 232 of your K20D user manual outlines how to use this Dust Alert feature for examining your sensor.

Alex
05-14-2008, 12:15 AM   #12
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Keep plugging!

Ernest - I read the entire thread and I offer this - I bought a K10D late winter at a great price because the K20's were coming.

I found this place (and another)

I try, and ask questions, and try some more and ask more questions - and everyone here with more experience (decades of it) patiently answers and encourages - and they love to see us post-up our images.

Picture taking was challenging enough when film was the capture medium and Kodak handled all the processing (with constant, predictable output). An SLR 10 or 15 years ago was just a box full of gears and springs, a prism and some glass in a tube that bent light rays.

Now we try to use a more powerful computer than the PC I bought in 1986; we capture photons on a device I don't even understand beyond thinking it is the reverse of an LCD television (light goes in instead of coming out) we do all the image processing ourselves on another PC that would have filled a room in 1970. We move all this information from one computer to another on a thumbnail-sized piece of plastic that carries 100 times more information than the hard drive of that computer I mentioned before.

I could go on, but the point is, don't despair - you have a great camera - right at the top of the best there are. Your issues are what we have all learned to accept as part of the modern world - you WILL master them, in time.

Then you and I can focus on the important calculus of this hobby - shutter, aperture and ISO - subject, light and composition - just as it was, is and ever shall be.

Keep plugging!
05-14-2008, 01:05 AM   #13
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QuoteOriginally posted by monochrome Quote
Ernest - I read the entire thread and I offer this - I bought a K10D late winter at a great price because the K20's were coming.

I found this place (and another)

I try, and ask questions, and try some more and ask more questions - and everyone here with more experience (decades of it) patiently answers and encourages - and they love to see us post-up our images.

Picture taking was challenging enough when film was the capture medium and Kodak handled all the processing (with constant, predictable output). An SLR 10 or 15 years ago was just a box full of gears and springs, a prism and some glass in a tube that bent light rays.

Now we try to use a more powerful computer than the PC I bought in 1986; we capture photons on a device I don't even understand beyond thinking it is the reverse of an LCD television (light goes in instead of coming out) we do all the image processing ourselves on another PC that would have filled a room in 1970. We move all this information from one computer to another on a thumbnail-sized piece of plastic that carries 100 times more information than the hard drive of that computer I mentioned before.

I could go on, but the point is, don't despair - you have a great camera - right at the top of the best there are. Your issues are what we have all learned to accept as part of the modern world - you WILL master them, in time.

Then you and I can focus on the important calculus of this hobby - shutter, aperture and ISO - subject, light and composition - just as it was, is and ever shall be.

Keep plugging!

poetraayyyy 8)

i have a nagging suspicion that the OP is delivering some kind of viral anti-marketing.
05-14-2008, 01:26 AM   #14
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yea these things are no reason to despair over pentax, and I would imagine are common amongst people who are coming from a P&S to an SLR. more like despair over having more problems due to greater complexity. but greater complexity in this case can open up a world of creativity! your pentax will be invaluable to your photographic journey I assure you.
05-14-2008, 03:04 PM   #15
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Okay, I'll say it. There is no "hot pixel issue" with the K20D. Up until two weeks ago, no one had even considered the K20D had anymore of a problem with hot pixels than any other digital camera out there.

Then, two review sites posted reports of problems, and a total of four (IIRC) individuals reported they had similar issues. This from a total of hundreds or probably thousands of online users. Believe me, people who frequent internet fora are not shy. If there was a rampant "issue", we would have heard many people screaming about it. Just look at the introduction of any new camera from any manufacturer. You'd think that every manufacturer out there just puts out total junk from all the rants and raves posted online.

Believe me, the K20D is one of the best values in dSLRs out there now. I honestly think it competes very well with Nikon's D300 which costs $600 (50%) more. I've taken low light action shots at ISO 2000 that my K10D literally could not take (mainly because it doesn't go beyond ISO 1600). The shots are clean and very sharp even at full resolution.

Okay, rant mode off.

Welcome to the fray!
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