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09-08-2015, 03:27 PM   #16
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QuoteOriginally posted by mikecomua Quote
I don't think there's any problem with your camera. I'd suggest you focus on a non-moving object, use tripod or place the camera on something solid, and take a couple of test shots, try both autofocus and manual focus.
If you can upload the photos here, with EXIF data intact, that would help members to provide possible solutions to your problem.

09-08-2015, 03:37 PM - 1 Like   #17
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OK, let's take a closer look at various factors.

This was taken with the DA L 18-55mm. This is one of the worst reviewed of all Pentax lenses for sharpness, particularly at wide open, and according to the EXIF, it was taken wide open. As aleonx mentions, Portrait mode tends to do this.

Taking a further look at the exif data, the subject distance is "close" and the zoom s at 47.5mm. Looking at the image, particularly the lines on the highway, the focus appears to be several meters in front of the two cars in the center of the image. So let's say the focal point is 10m in front of the photographer. Using the Online DOF Calculator and rounding up to 48mm, that gives an in-focus zone of only 12.8m total, with only 3.3m in front of the focal point which squares quite well with the relatively in-focus zone, particularly the relatively in-focus trees to the right and the out of focus sign in the front.

Additionally, the cars on the highway are moving at highway speeds (100km/hr+). At these speeds and magnification, even 1/500 likely will not be a fast enough shutter speed to get sharp definition on the cars, even when moving parallel to the lens.

Looking at the edges of the image, pretty much everything falls outside of the zone of focus, except the leaves in the upper right, which are reasonably sharp considering the poor quality of the lens. This, along with the lack of clear astigmatism or CA, indicates that this isn't a decentering issue.

In sum, poor equipment + unpracticed technique + deceivingly difficult subject matter = a poor quality image.

Incidentally, this image shows very little noise, but that's not surprising, since it's a bright scene with a low ISO.

My advice: Think about upgrading the lens (it need not be an expensive lens - several inexpensive zooms are substantial upgrades on this one), and read up on the relationship between aperture, sensitivity, and shutter speed. While there is a small learning curve, I'd wager you'll end up finding your camera easier to use in the long run, and you'll be much more satisfied with its output.

Last edited by dcshooter; 09-08-2015 at 04:53 PM.
09-08-2015, 03:52 PM   #18
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I've had a KM since I think 2009. It works perfectly, takes great photographs, is very durable. I think you have a damaged camera. How experienced are you with a DSLR ? I'm not saying it's you, but just wondering .
09-08-2015, 06:19 PM   #19
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QuoteOriginally posted by dcshooter Quote
This is one of the worst reviewed of all Pentax lenses for sharpness
Hey! Go easy on the DA L 18-55. It is optically the same as the more highly regarded DA 18-55 II and capable of decent results within its limitations. Those limitations are softness at 50mm+ (particularly wide open) and barrel distortion at the wide end, but overall, the lens is an appropriate match to the K-m as a kit offering.

Aside from that, I agree that a change of settings away from portrait to a more appropriate scene mode or at least regular program exposure (P mode) might improve things.


Steve


Last edited by stevebrot; 09-08-2015 at 06:27 PM.
09-08-2015, 06:40 PM   #20
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Eh, it might have the same optical formula, but it is the budget line lens and is not necessarily produced to the same tolerances. The 18-55 II itself only gets an average sharpness score of 8 on PF reviews, which isn't stellar and places it among the worst rated of the DA-era lenses for sharpness and tied with the second worst of the DA Ls!. Now to be fair, these are subjective reviews, but both lenses have a large number of reviews here, so the overall ratings are comparably trustworthy.

"More highly regarded" in this case isn't saying much. It's just not a sharp lens, especially with the parameters used in the example pics.

QuoteOriginally posted by stevebrot Quote
Hey! Go easy on the DA L 18-55. It is optically the same as the more highly regarded DA 18-55 II and capable of decent results within its limitations. Those limitations are softness at 50mm+ (particularly wide open) and barrel distortion at the wide end, but overall, the lens is an appropriate match to the K-m as a kit offering.

Aside from that, I agree that a change of settings away from portrait to a more appropriate scene mode or at least regular program exposure (P mode) might improve things.


Steve
09-08-2015, 08:08 PM   #21
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I don't have experience with a KM, but it seems that on balance, dslrs in general, and pentax models in particular, don't have the same knack for producing excellent results effortlessly compared to many p&s cameras. So maybe this is partly a case of a p&s user being legitimately disappointed by their initial results using default settings, possibly combined with a less than stellar copy of the kit lens or some other actual problem.
09-09-2015, 12:26 AM   #22
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Thanks a lot for the advice, guys. Here are some pictures I took this morning on AV mode with f8 and Shake Reduction turned off. Still seems pretty skewered up, though

https://drive.google.com/file/d/0B6u-apc8zXe6WTZDenFaUnZYZ1E/view?usp=sharing[COLOR="Silver"]

Last edited by mikecomua; 09-09-2015 at 12:59 AM.
09-09-2015, 02:12 AM   #23
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QuoteOriginally posted by stevebrot Quote
Hey! Go easy on the DA L 18-55. It is optically the same as the more highly regarded DA 18-55 II and capable of decent results within its limitations.
True, as far as kit lenses go, the Pentax 18-55mm were not as bad as some others from previous decades or other brands. That said, its still one of the worst lenses in the current lineup - of course, its the kit lens, after all. So OP, if you can try another lens, like DA 50mm f1.8 or DA 35mm f2.4, you would immediately get sharper images.

Regarding the IQ, the posts above have already explained a lot. In the sample images, I don't see noise as a problem. Of course, the tech in K-m is several generations old, so its high ISO is nowhere near the current lineup's capabilities.
One more thing to think about is SR. If you have SR activated, you might want to half press the shutter and wait for half a second before pressing it all the way, so the SR activates. At 1/500 shutter speed, the SR doesn't need to be active, though.
The bigger problems in those samples are aperture and focus. I would suggest you try using Av mode and f-number between 7 and 12. That ought to give you the best sharpness that that lens is capable of. Around zoom 35mm and f8, that lens has its optimum sharpness.

And sorry if there are too many posts claiming user error, its just that we often get threads where someone is saying how bad the camera is, and then the problem can be traced to a simple user error. We don't know how knowledgeable you are, so sorry if you feel attacked. Thats not our intention, we just try to find the problem as quickly as possible, and the problem is rarely the camera. If its the camera, its usually unusable, rather than just "diminished IQ". The lens is another story, that would be the next thing to check. Maybe you can find a store locally where you can "test" a lens before purchase by taking one or two snaps with it on your camera. You can try a high end Pentax lens, see how it performs on your camera. Or if you have a friend with a lens, or if you are willing to buy a lens. For IQ, it can even be an old Pentax M 50mm f2, which are super cheap. These are not fully automatic, so they are a little more difficult to use, but from f3.2 to f11 these are great. Just in case you want to do a test but don'T want to spend money on a brand new modern lens.

09-09-2015, 03:52 AM   #24
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QuoteOriginally posted by mikecomua Quote
Thanks a lot for the advice, guys. Here are some pictures I took this morning on AV mode with f8 and Shake Reduction turned off. Still seems pretty skewered up, though

https://drive.google.com/file/d/0B6u-apc8zXe6WTZDenFaUnZYZ1E/view?usp=sharing[COLOR="Silver"]
Some parts of that photo looks pretty sharp to me. Most notably the awning frill above and the street sign, left.
09-09-2015, 05:59 AM   #25
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Skewered up? Honestly, this one indicates to me no problems with the gear

As Mark says, it's reasonably sharp across the frame, as to be expected when shooting at F8, which is this lens's sweet spot, and at a shorter focal length (40mm), where the lens tends to perform better.

The only noticeable (slight) noise is in the shadowed areas to the left, again to be expected with older sensor tech, as Na mentions. There is no unreasonable Coma or CA.

The lighting conditions aren't great for the scene, so you are going to get a lot of harsh shadows, but it's all static objects, so you don't see the motion blur you would with the fast-moving cars in the first example image.

The color seems a little dull, but that's something completely adjustable for out-of-camera jpegs and is solely a matter of my own personal taste.

Keeping this in mind, I suppose the salient question is what exactly do you see as wrong with this particular photo, and what do you expect to look different about it, bearing in mind that this is a 6+ year old entry-level DSLR?

Looking at your complaints in your original post about the camera in general:
1. The images have a lot of noise - this one does not.
2. The images are "extremely blurry" - this one is not.
3. The images don't have a lot of detail - this one has about exactly as much as you can expect from a 2009-era 10MP sensor on an entry-level DSLR with a kit zoom.
4. The images overall "look like crap" - impossible to evaluate the influence of the gear itself vs. user ability and experience without looking at several examples of "bad" images from this camera compared to examples of what you think the images should look like in order to pick out the meaningful differences.

The two images you provided so far are boring, bland images taken with pretty much zero regard for composition or artistic value. This is not me trying to insult you or critique your ability as a photographer at all, since I have no familiarity with your body of work as a whole and am perfectly cognizant that these are test images.

However, the factors I outlined in my post above first one suggest that a better technical understanding of the way image-making with a DSLR works might help you to get images closer to what you want, but that is just one judgment from a single image. But the fact that the second image seems to me to show nothing wrong with your equipment suggests to me that you are looking for answers that go beyond merely upgrading your gear.

Of course, if a sharpness upgrade indeed is all you are looking for, then the lens suggestions in some of the posts above will give you immediate tangible results. However, I'm in the camp that thinks that any camera model can produce good pictures if the photographer understands the abilities limitations of his or her tools and knows how to work with or around them. But that's more a matter of experience than anything else.

QuoteOriginally posted by mikecomua Quote
Thanks a lot for the advice, guys. Here are some pictures I took this morning on AV mode with f8 and Shake Reduction turned off. Still seems pretty skewered up, though

https://drive.google.com/file/d/0B6u-apc8zXe6WTZDenFaUnZYZ1E/view?usp=sharing[COLOR="Silver"]
09-09-2015, 06:14 AM   #26
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QuoteOriginally posted by mikecomua Quote
Thanks a lot for the advice, guys. Here are some pictures I took this morning on AV mode with f8 and Shake Reduction turned off. Still seems pretty skewered up, though

https://drive.google.com/file/d/0B6u-apc8zXe6WTZDenFaUnZYZ1E/view?usp=sharing[COLOR="Silver"]
In what way is this skewered up to you?

It looks within what I'd expect from the kit lens. Underexposed a little to my tastes, but the Pentax default exposure leans towards preserving highlights, it's up to the user to adjust EV to their liking. Likewise the colour, contrast, etc. settings of the jpeg are adjustable to your taste as dcshooter has mentioned.

What is the end purpose of your photos? If it's to view them on screen at 100%, then the kit lens and your k-x will always fall short of the newer cameras, fancier lenses, and a solid, locked down technique. If it's normal web sized viewing, or printing at the most common sizes, what you have should be more than enough when paired with solid technique.
09-09-2015, 06:52 AM   #27
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One thing with a DSLR is that it doesn't give better quality than a P&S. It just has the potential for better quality. This is why photography takes skill and experience. Seems you are on the right path, OP, the last photo you posted is nice and sharp, detailed If you want anything better than that, you will need to find light with good quality (sunset, sunrise), use flash (strobes, bounced flash, diffused fill flash, and so on), tripod (when using tripod, disable SR. Bonus points if you use remote or 2 sec timer), raw photo processing software (Lightroom, Aftershot pro, FastStone, etc.), a better lens (apart from DA 35mm, DA 40mmXS, and DA 50mm, you can expect to spend over $300 for a good lens, often around $1000), a current model of camera (with digital cameras, you can't just buy a better film, you have to buy a whole camera to get a newer, better sensor. Technology is constantly improving).. In that order. But skill still comes first and has to be developed with each new piece of gear, each new part of the process. Of course, if you photograph a highway and a brick wall, it will take a lot more work to find a good angle, light, to make it look attractive. Subject is important, too.

Edit: For now, you can just press Info and select the kind of jpeg mode that you find pleasing (Vibrant, Film Reversal, Black and white, bleach bypass are quite popular), or even adjust it yourself. Play with NR settings and lens corrections that the camera offers.
Edit2: Tamron 17-50mm f2.8 is a fairly good, affordable zoom lens. It will be significantly better than the kit lens, sharper, better low light performance.

Last edited by Na Horuk; 09-09-2015 at 07:03 AM.
09-09-2015, 06:52 AM   #28
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I agree with the others that, on the last picture, it's about as good as it gets with this lens/body combo. Now, for the contrast/sharpness/color you can use different jpeg settings or, even better, shoot in raw and adjust to your liking in Lightroom or other software.

Don't forget that when you see a great picture, no matter what equipment was used, they're rarely "direct from the camera" jpegs. More often than not, they're raw files that have been carefully adjusted in post-processing by the photographer to get the picture it wanted. Today, getting the image with the camera is only part of the story and post-processing also plays a lot.

Last edited by CarlJF; 09-09-2015 at 07:25 AM.
09-09-2015, 07:01 AM   #29
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Just to support what others have said... that kit lens is quite poor. It will do the job in a pinch, but you will never get AMAZING quality out of it.
Actually, kit lenses that were sold with film cameras in the past are giving better IQ than that lens.
09-09-2015, 08:20 AM - 1 Like   #30
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OK, So here's a question for you. Would you be happy if your camera produced images that looked like this?


Here's why I ask. I took this photo in 2009, when I was just starting to get into digital photography. The camera I used was an Olympus E-410, basically that company's similar-vintage equivalent of the entry-level K-M. I used their kit lens equivalent of the one you are using. But the thing is, in many ways the Pentax is the superior camera. The Oly has a smaller 4/3 sensor, which has poorer dynamic range and noise characteristics than the APS-C one. It also lacks in body shake reduction. The lens probably resolves a bit better than that on the Pentax, but since the sensor is smaller, the performance ends up being a wash.

But let's take a closer look at the image. Here are some crops, blown up to 200% so you can see some the weaknesses of the camera:


This is an in-focus portion of the image. It's not substantially sharper than the in-focus portions of the second image you posted. If anything, it's less sharp.


This is a darker portion of the image. It shows worse chroma and luminance noise than your second example pic's shadow portions. Bear in mind that I took this image at the same ISO settings as yours.


This is an example showing highlight blowout and chromatic aberrations in overexposed areas. Your KM actually has better dynamic range performance than this.

The thing is, however, that I by this point knew my camera pretty well and had a scene and setup that produced a nice image. I was working on a project in Utah at the time, and this was the view from out the front door of my motel room. I'd routinely see these amazing sunsets over the neon-lit diner in the foreground, and decided I wanted a snap of one, so I positioned the camera on the railing in front of my room, stopped down to an aperture where I knew I'd get decent sharpness throughout the image, set the exposure to an appropriate level, then set the self timer with two second mirror lockup to get a reasonably sharp image.

I also took the image in RAW, and used the Olympus equivalent of the Pentax Camera Utility to develop the image so I got the color saturation and tonality that I wanted.

While I have no doubt that I could take a much better image even than this using the same camera with 6 years added experience today (my eye for composition has certainly improved!) , the point I am trying to make is that I by this point in time I was quite familiar with how my camera worked and was able to produce an image that I was very happy with. Granted, I had some film photography experience already, but the way I arrived at this point was by reading the manual cover to cover, reading several other digital photography books, and then going out and taking LOTS of pictures (and postprocessing them) to familiarize myself with my gear. Learning and practice have always been and will always be the only way to get the best images possible form your current gear and will only help you improve your images more if and when you upgrade to higher-performance gear.

Last edited by dcshooter; 09-09-2015 at 08:25 AM.
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