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12-14-2009, 12:04 PM   #16
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I think that part of the problem with using the Pentax-supplied raw conversion program is that it results in the same processing as their jpeg engine. You should still however get more detail out of the image, aside from that it will likely turn out the same with regards to color.

Is it possible the programs you are using for converting raw haven't been updated to work with the K-x files yet? Sometimes this can also be a problem initially with a new camera, but I am not too familiar with this part of the conversion software realm.

12-14-2009, 12:06 PM   #17
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All those pictures seem ok to me.
I think that you should forget a little about the technical side of things. I mean, who really cares about the difference between a CCD and a CMOS sensor apart from those who take pictures of the sky at night? Don't focus on the nerdy side of photography, focus on light, composition, etc, enjoy taking pictures!
You can try the Gimp as a free software.
12-14-2009, 12:12 PM   #18
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You've got good results Manfred, don't mistake atmospheric haze for a decreased image quality.
A stated, rarely do images straight out of the camera come out just the way you want them to. RAW captures even less so, given none of the post-processing parameters are applied to the image. Shooting JPEG alleviates some of this angst but then commits your results to a decreased latitude of useable dynamic range.

For a well-exposed photo, JPEG out of camera is not the best anyone can get IMO. It may come close, but there can always be a colour/levels/curves adjustment that can be made in post-processing that will improve the look of the image straight from the camera.

If you have no experience with RAW converters, I'd advise to just learn the one you've been supplied with (Pentax Lab) as it's quite a powerful programme. You'll need to learn the capabilities of Photoshop. There are endless tutorials online, but even better are the instructional books like David Giordan's Art of Photoshop book.

Understanding exposure settings also goes a long way in knowing the best way to shoot a scene and not be disappointed by noise levels. If you're getting more noise now from your K-x (which trumps just about all APS-C cameras available today in high-ISO noise performance) compared to your P&S, then something's wrong with the way your pictures are exposed.

Your results here look fine, now go ahead and enjoy your fine little camera that truly is the envy of many.
12-14-2009, 12:13 PM   #19
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a couple quick comments:
if using RAW, haze/cast could be RAW converter mishaps - if you are not already, make sure you are shooting in DNG to ensure the RAW is being rendered the correct by Adobe way. When the K-x first came out, when shooting in PEF, I had various camera profiles (i.e. Adobe Standard, Camera Standard or something, Pentax 1.0) to choose from in Lightroom - which said it supported K-x RAW files - but each profile looked slightly different.

haze/cast could be reflections on particles in the air particles that you don't notice with your eyes unless you magnify a lot by blowing it up on screen or using binoculars on a scene far away. Use a polarizer and see if it changes when you rotate the polarizer.

I have not blown up the P&S picture but if you want something that looks more like that, try choosing landscape custom image or turn up the in-camera saturation. If you want something more 'real', at least in my experience, use Natural. In any case, while I was not where you were taking pictures, they look normal.

Hope this helps

12-14-2009, 12:27 PM   #20
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QuoteOriginally posted by Manfred Quote
Marc, thanks for making me feel better! If you say the picture looks OK to you, then it's probably just that I was expecting too much.
And I'd wonder what was setting your expectations. That is, what other camera have you ever seen that would produce better results when focusing in the distance on a humid day and then zooming in to the extreme magnification of the crop you posted? Any camera that tried to convicne you that there was as much contrast in that part of the scene as in parts of the scene that are closer is lying to you. The atmosphere does not work that way. Only on the moon would you get an image that has as much contrast in the distance as in the foreground.

QuoteQuote:
In many places I read that the out-of-camera JPGs from Pentax DSLRs are generally not very good, and that one should rather shoot in raw mode, and process the raw files in the computer.
Now you know why man of us tend to be annoyed by such comments in reviews. How exactly you want your images to look is a personally thing, and if some random reviewer somewhere happens to want sharpness turned up more or whatever, so what?

QuoteQuote:
For a normal, simple, straight, well exposed photo, is the JPG from the K-x really as good as it can get?
See above. Way too much about image processing is subjective to get any reasonable answer to that question. If there were only one bets way to process an image, then there would be no reason for different image processing settings, in camera or in software.

QuoteQuote:
That would be in conflict with those ubiquituous statements telling that the Pentax in-camera JPGs are no good.
Ubiquitous? Name two other than dpreview.

QuoteQuote:
But IF it IS possible to get better quality by extrenally processing the raw files, then HOW EXACTLY is it done?
Again, see above. it's all subejctive. The answer is to learn exactly what *you* like, and how to use the controls in the software *you* have to achieve those results. And the answer will different from image to image.

QuoteQuote:
What I was expecting in the test shots was, very simply stated, seeing on the monitor something as closely similar as possible to the real thing I see out of the window.
Again, on my monitor, it looks extremely realistic. Can you even see those red flower with your unaided eye? even if you look through binoculars, what happens is that your eyes constantly readjust (iris opening and closing) as you scan about a scene to optimize "exposure" for each part of the scene separately. A camera won't, can't, shouldn't do that.

QuoteQuote:
the general green of the vegetation, which looks much too yellowish).
I'd say monitor calibration is in order, then. But in any event, you're talking about a WB issue here - that's the easiest thing in the world to alter in PP. Contrast and saturation shouldn't be invovled at all.

QuoteQuote:
The problem is that when I simply crank up the contrast and saturation settings, I get more noise (grain) than what I would expect to get from a camera that has been as highly rated as the K-x. The grain I get is not tremendous! It's just about the same, or a little bit more, than that of my cheap point&shoot camera when it is delivering the required contrast and saturation.
You'd have to post apples-to-apples comparison shots - same scene, same exposure, etc - to convince anyone of that.

QuoteQuote:
It's just that I expected the K-x to be significantly better than the little point&shoot bought four years ago! After all, one of the main advantages of having a "big" APS-sized sensor is supposed to be lower noise!
Try shooting comparing both cameras at ISO 3200 and tell me how that goes.

QuoteQuote:
I don't have special calibration hardware
Then viewing on screen can give you no basis whatsoever for talking about color.
12-14-2009, 12:34 PM   #21
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The fundamental issue is that you're just way, way out of your league in regards to the processign side of digital. You clearly know what an f stop is and the like but you're missing th eboat re. processing.

if you want to do better than what you posted you need to shoot raw, select the green channel (maybe blue as well), alter the colour balance then increase the luminance to spice it upa bit.

This goes for any camera. Your camwera is trying to balance the blue of the sky withth e green of the grass, impossible ... hence, we use raw to selective edit different parts of the image.
12-14-2009, 12:51 PM   #22
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Paul, some more comments:

About the time I shot the first test photo posted here: It was just 3 and a half hours after sunrise, and another three and a half hours before the sun reached the highest point. So this was FAR from being direct overhead sun. The landscape looked nice and contrasty.

The local summer time here is pretty shifted against solar time. That's why sunrise is at about 7 am, noon at around 2 pm, and sunset at about 9pm. So, the time with harshest overhead sun here is from about 12 to about 4pm.

The second test shots instead, those comparing the P&S to the K-x, were taken just at solar noontime.

The P&S is a Canon Powershot A400.

I didn't photoshop anything in the test shots shown here. Only the flower photo had a very slight sharpening applied after downsampling. That was done with FastStone, not with Photoshop. The test images were not processed in any way other than downsampling to make them fit in this page.

Yes, there is some moisture in the air, but not very much. The relative humidity right now (4:20 pm) is 54%, and the temperature is 22.6 degrees Celsius. At the time I shot the first test, the relative humidity must have been higher, but the temperature much lower, equating to a total moisture contents in the air lower than the one right now. At the 54% and 22.6 degrees I have now, the moisture must be at around 10 or 11 grams of water per cubic meter of air. At the time of shooting the first test photo, it was probably below 8gr/m3.
Aside from these numbers, the closer landscape including those houses looked really clear, not hazy at all. Only the far background, under those clouds, was hazy.

Glad to read that you think the leaves on the flower photo are OK. Maybe it's just my monitor, or my eyes. The monitor is over ten years old, and the eyes are 44 years old. What can you expect...

Indeed I enjoy knowing what's going on, and not just go shoot away blindly. As an engineer, I probably won't ever be able to overcome that attitude! Sometimes that works against me, but for the most part it's helpful. During the last few days, of course, my photography has been 100% engineering and 0% art! I'm sure this ratio will improve markedly once I get in control of the K-x.

Indeed I don't think the programs I'm using have anything specific for the K-x in them. In fact, the list of cameras supported by DCRAW does not include the K-x. But the formats are supported, of course, both the PEF and the DNG. But I wonder whether DCRAW would do any optimizing for specific cameras. I have configured it so that it's taking the white balance coefficients as the camera states them. I let DCRAW calculate the black level from the dark pixels at the side of the frame, and I set the saturation level to a slight headroom above the camera's saturation, to make sure there will be no blowing. I use the highest quality demosaicing, and have tried several different options for highlight management, but found best to avoid highlights at all by raising the saturation limit for DCRAW beyond that of the camera. As long as the camera doesn't saturate in any color, that works well. If instead the camera saturates some area, that area gets a color cast during DCRAW processing.

I have this pretty well under control, I think. But I don't get any better quality than from the plain camera-generated JPGs.

Zav, it just happens that I AM a bit nerdy! But I fully intend to get back to true photography. It's just that during the last few days I have been going through toothing pains with the freshly arrived K-x. To do real photography with the K-x, I first need to understand what this camera will do under which conditions, and how to take the best advantage of its capabilities. Once I have gotten past that stage, hopefully a few days from now, I'll get back to photography.

Will have a look at Gimp.
12-14-2009, 01:06 PM   #23
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Comparing the P+S and the Pentax, basically the P+S is shifting a little more blue, hence your greens are greener. However now your sky is posturised.

All you are seeing is a slightly warmer WB selected by Pentax, frankly it's odd as Pentax is often criticised for being a little too cool on colour spectrum.

12-14-2009, 01:32 PM   #24
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See, I'm really just jealous of your beatiful weather (2nd snowfall of the season here in frigid Minnesota), so don't pay me too much attention if I seem crabby, haha.

The haze showing up in the more distant parts of the photos really is from humidity - its much worse here mid-day in the summer with 90%+ humidity - shots can get hazy easily within half a kilometer. Though there isn't much to base the distance on, I would hazard a guess that the landscape your view is covering ventures well beyond a kilometer in distance! 10-2, 12-4, its mid-day either way! Lets see some artistic shots at 7:15 in the morning, or 8:45 tonight!

Judging by all the numbers you were throwing out, you definitely are a nerdy engineer! Nothing wrong with that I'm quite geeky myself (the objective difference between nerdy and geeky of course being the former is much smarter than the latter...but with geekiness comes self deprication as well - its a tradeoff!)
12-14-2009, 02:00 PM   #25
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Well, folks, I think the picture is getting pretty clear.

My problem was composed of a mixture of poor raw processing, lack of perfect monitor calibration, too high expectations regarding color saturation, coming from shooting slides for 30+ years, and some light haze in the distance.

I don't think it makes sense to continue forever with the thread, but I feel I must comment on what you have written! I have spent the day here, and everytime I post a reply, tehre are several new posts by you! I'm really greatful for all the help.

I will try again with Pentax Lab (Silkypix), but I don't know if I will get to work it. It's really acting up on my PC.

I was doing all my raw shooting in DNG format.

I tried some test shots now with a polarizer, and as expected, it does improve color saturation of the foliage, the flowers, and cuts significantly better through the haze in the far background. I didn't use the polarizer earlier, because I think that to test the camera against the P&S, and comparing to what the landscape looks to the naked eye, it's more fair to shoot without the polarizer. Anyway, I can't use that polarizer except for shots that don't require much sharpness, because it acts a lot like a softener too! A lot of detail is just gone when using the polarizer. Not as much as with the K-X's "toy camera" filter, but in that line! ;-) Looks like I need a better polarizer.

I see now that there is NO issue with in-camera JPGs, at least with this model. I had seen many people complaining about poor in-camera JPGs with several or all Pentax DSLRs. There is a review of the K10D on photographyreview. com that mentions it, also there are threads on this very forum about it, and several people commented privately to me about it. I really don't know whether this is a real problem with older model and has been fixed in the K-x, or if it is simply an urban myth, but clearly the JPG's produced by the K-x do not seem to have any problem, when compared to the raw files.

Yes, I can very easily see the red flowers in the distance with the naked eye. Not well enough to see individual parts of teh flowers, and with some difficulty to separate one flower from its neighbors, but I can clearly see the brilliant red color in them.

I cannot do a comparison between the P&S and the K-x at ISO 3200, because the P&S only goes to ISO 400. So I was comparing them at ISO 200, which is covered by both of them. The P&S actually was in auto-ISO mode, but judging from the time and aperture registered in the EXIF data, it was actually working at ISO 200.

Indeed the high ISO performance of the K-x is very much better than anything I have seen with slide film. I cannot compare to other cameras, because I don't have any other digital camera than the K-x and the little Canon Powershot A400.

Yes, indeed the K-x, set to daylight, tends to be a bit warm. But auto white balance works very poorly when one shot is dominated by green foliage and the next is dominated by blue sky, with the third being 80% deep red flowers! So I will either have to walk around with a white card and do manual white balancing, or else correct it in the computer. I didn't do that, because I have found it much too easy to do it wrong, because the eyes get so badly influenced by ambient light.
Maybe the best is to take a white card, shoot it under different lighting conditions, then take the uncorrected raw files and look at the color levels in them, to calculate the factors necessary to do my own white balancing by numbers, engineering style.

Alfisti, I don't fully get what you mean to do with the green and blue channels. Anyway the camera was set to daylight, not auto WB, so it wasn't trying to balance anything. With auto WB the results were worse, which is no surprise because this scene just doesn't have the same amount of all three colors.

Well, I will leave it at this, I guess, and go back shooting, playing, learning. When the time comes to get a printer and use it, a whole new world of issues will show up...

Thanks to you all!
12-14-2009, 02:38 PM   #26
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You are always balancing WB, that's why it's called wb

The correct hue to render a blue sky may not work on green grass.
12-14-2009, 07:47 PM   #27
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A point and shoot is very capable of turning out decent images in good lighting conditions. It actually will have greater depth of field and generally will be over saturated. Most dSLRs are tuned to be more "natural." That is to say, they tend not to bump up the saturation quite so much. The place where you really see the difference between a dSLR and a point and shoot are when you want to shoot with smaller depth of field, or in low light situations (without flash).

I guess one other thing I would say is that red is tough color for many digital SLRs to handle. Not certain what it is about that color, but it often doesn't come through quite as well as other colors.

I process using adobe's ACR for RAW and it works fine, but it does take some time and reading to understand the process. Better to begin with in camera JPEGs and change to RAW when you feel that it isn't adaquate for what you are doing. Also, PEF's are fine for editing, as long as your editing program handles them fine.
12-14-2009, 08:11 PM   #28
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QuoteOriginally posted by Manfred Quote
Yes, there is some moisture in the air, but not very much. The relative humidity right now (4:20 pm) is 54%, and the temperature is 22.6 degrees Celsius. At the time I shot the first test, the relative humidity must have been higher, but the temperature much lower, equating to a total moisture contents in the air lower than the one right now. At the 54% and 22.6 degrees I have now, the moisture must be at around 10 or 11 grams of water per cubic meter of air. At the time of shooting the first test photo, it was probably below 8gr/m3.
Aside from these numbers, the closer landscape including those houses looked really clear, not hazy at all. Only the far background, under those clouds, was hazy.
You're comparing what your unaided eye saw against a many, many times magnified view from your camera. Unless your house is located o the moon, there is just *no way* a house that far away was not *much* lower in contrast than what was right in front of you. as I said, any camera that tells you otherwise is lying, but feel free to the shots from your camera to compare. As it is, looking at the full image, I see the P&S shooting about half a stop less exposure, and with an unnaturally high level of saturation and contrast overall, which is indeed typical of P&S cameras. If you prefer that look, you can similalrly turn up saturation and contrast in your DSLR.

Last edited by Marc Sabatella; 12-14-2009 at 08:22 PM.
12-15-2009, 07:26 AM   #29
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Manfred, to my best knowledge Faststone uses dcraw to develop raw pictures. And the default output from dcraw has some grey "haze" as some people call it, I know since one of the programs I use (Picture Window) uses dcraw too. It's hard to make it shine -although it has its benefits too.

I would suggest too that you try another program for raw development. You could try the one that was supplied with your camera, or e.g. Raw Therapee -it's free.
12-15-2009, 10:24 AM   #30
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Dear all,
here I'm again, now much happier than before.
I have finally found a software setup that works very well for me, even if it's a combination of four programs:

- FastStone to browse, preview, sort, delete, rename, images, and also to casually and quickly pull a modest JPG out of a DNG file. But when I want to generate a high quality output file, I send the selected DNG over to

- Gimp. I downloaded this yesterday, following advice from several people, and it works really well. But it only works in 8-bit mode, and anyway it doesn't natively understand DNG nor PEF. So I also installed

- UFRaw. When I tell Gimp to open a DNG image, it will call up UFRaw, which is simply a well made and very controllable front end for

- DCRAW. That way I get the full quality of DCRAW, with the easily adjustable and real-time previewable settings of UFRaw, doing most of the process in the 16 bit domain, and then I can crop, bend, warp, downsample and unsharp mask to my heart's delight in Gimp.

It seems that DCRAW has some bug that shows up when processing PEF files from the K-x. The hues are totally rotated. But with DNG it works perfectly, and anyway the DNG format should be preferable, being a more widely supported standard.

I have yet to do any serious work with this, but the tests so far are very promising, allowing me to easily get excellent color balance, vary saturation and contrast from very soft over totally natural right into Disneyland-style, without getting any abnormal noise, haze, or the like. I'm happy with this setup.

My taste regarding saturation does not go as far as what that P&S produces. Rather, it ranges from 100% natural, to a tad oversaturated, with the latter typically used for macros and landscapes and the natural setting for everything else. Regarding contrast, I tend to prefer it significantly stronger than in real life. Probably that taste comes from having used Fuji slide film, underexposed by 1/3 stop, for well over 20 years.

My monitor remains a problem, though. The only way to get natural colors in the mid/high brightness range is by setting the monitor's brightness control to a level that pushes the dark areas all the way into black. It had this problem since new, and years ago I adjusted it internally to improve this as far as possible, but that wasn't a complete correction. At least it does have neutral color all over the range, but the density curve is impossible to get right.

I will probably have to get a new and better one. But they are all wide-screen LCDs nowadays, and I don't even know whether my graphic card can drive such a beast. It was born in the days when wide screen was reserved to the cinemas! And a new graphic card surely won't fit my old PC, and a new PC wont have the legacy ports which are crucial for me. Life is difficult...

But for the moment, getting a few hundred photos into the K-x, hopefully including a few really worthwhile ones, is more important.
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