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10-02-2016, 06:15 AM   #16
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Your depth of field (part of the picture that is in focus) is much shallower with The k-x than with a point and shoot optio because the K-x has a larger sensor, so more of the picture is going to be out of focus. Look at the background it is much more blurry. Especially at close distances. So you need to stop down if you want more of the photo in focus. Work from a tripod and use the two second delayed exposure, that way you can still shoot at ISO 100 at F8 or F11. You could also use liveview for focussing. It is more accurate (when it focusses where you want it to).

10-02-2016, 07:14 AM   #17
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In the exif it says "resolution 600x900". Am I to understand that you were using a low resolution on the camera settings? It is difficult to diagnose from resized pics. The resolution of the Kx's 12MPx sensor is 2848 x 4288 pixels. To realise best sharpness get full sized images out of the camera, then process on your PC. A simple (free!) program like faststone is fine for resizing and sharpening (all resized images need resharpening, the reduction in size softens them) jpg's, and also tweaking levels, contrast etc. For the image results that you are looking for it is time to move away from point and shoot to diligently setting up your shots (tripod etc) - and developing the results to suit your ends.
Looking at your flickr pics the Kx image is less sharp than the optio, partly this is depth of field (massive depth of field at 8.5mm on the optio), partly the 18-55mm kit lens IMO (NOT the sharpest lens at 45mm f5.6, f5.6 is wide open at the long end* on the slow kit lens, all lenses are at their softest wide open), partly possibly because hand holding at 45mm 1/160th is much more likely to result in a wee bit of shake affecting the image than hand holding the optio at 8.5mm 1/60th, and significantly, to my eyes, because the Kx pic is front focussed. IMO the sharpest plane of focus is above the knees on the dolls legs. From this point most of the dolls are receding slightly out of focus. This could mean that the focus needs to be callibrated for this lens - there is plenty of info on doing this for lenses which are front/back focusing - but in any case for still lifes like this I would routinely manual focus. However I've not used a Kx so I'm not sure how good the live view is - it wasn't very good on a K20 I had for a wee while. Certainly its 230k 2.7" lcd is a lot lower spec than my K5's 900K 3". Which would prompt to some other focus aids eg a viewfinder magnifier like the OME53. But in any case MF is largely a matter of practice and familiarity.

So I don't think you have managed to get the best out of the 18-55mm by any means and would echo many of the previous comments re stopping down, lighting, tripod. But in any case, I would recommend immediately picking up a "nifty fifty". 50mm is a pretty good focal length for portrait on APSC sensor cameras. One of the pentax 50mm is obvious choice, f1.7 best price/performance, f2 is fine. The "M" series 50 1.7 should be readily acquirable for about 50 bucks. Now put that on the Kx, shoot at f5.6 (which is now no longer wide open but 3+ stops stopped down), buff up the pics as suggested and your results should be as sharp as you want! Or at f11 for more DoF.
Finally please don't be discouraged Your pics are not far from looking great
*Just did a quick test, 45mm is about the point where f4.5 becomes f5.6 as the kit lens is zoomed.
Second quick test: banknote. DAL18-55 @ 50mm f5.6 top, SMC-A 50mm f1.7 @ f5.6 bottom. Standard technique; tripod mounted, 2 secs timer shutter allows all wobbles from touching the camera and mirror vibrations to dissipate. 100% crop from full sized jpg, K5. Very clearcut difference in resolution (more clear when viewed on my PC, I find uploaded pics tend to be reduced in resolution).




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Last edited by marcusBMG; 10-02-2016 at 09:04 AM.
10-02-2016, 08:37 AM   #18
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Cameras are only as sharp as the lens and the user.
10-02-2016, 08:53 AM   #19
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For still life you need:
a) low ISO (hopefully ISO 100)
b) 2 sec timer or remote trigger
c) Aperture of F8 (possibly f11, depending on lens)
d) Focus using single point, AF.S. Remember that the AF point is quite big, so sometimes it locks onto something you might not want it to.
e)lights that enhance details and contrasts (so, not direct lights, but from the side so things look more 3D, with shadows in the right places)
f) EV +/-, as sometimes you need to adjust this to get optimal exposure
g) shoot raw, post process photo. If you shoot jpeg, try one of the better jpeg modes (like film reversal). You can also increase jpeg sharpness and contrast in-camera.

The photos you posted are acceptably sharp and detailed. With the above instructions you might get a small improvement. IF you want a large improvement you need better lens (kit lens will, by definition, be one of the worst lenses in the current lineup), shoot raw and post process (using FastStone, Lightroom, RawTherapee, SilkyPix, Aftershot, or one of the other PP programs)

Remember, P&S cameras are for Auto mode. DSLRs are for skillful setups and knowing what settings to use to get the results you want. The other difference is that the DSLR photo has more MP, detail, bigger dynamic range, less digital noise, and better colours.

10-02-2016, 05:30 PM - 1 Like   #20
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QuoteOriginally posted by Wheatfield Quote
Cameras are only as sharp as the lens and the user.
not entirely true, I know some good photographers who are as dull as a crayon.
10-04-2016, 12:07 PM   #21
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QuoteOriginally posted by Digitalis Quote
you're expecting the DA 18-55 to be razor sharp at f/5.6?...
Not really... camera picked that aperture in P mode. Which is why I've gone to aperture priority for more shots when results haven't been sharp, and tried f8, f11... still not always sharp. But, from other comments it appears the lens isn't the greatest.

QuoteOriginally posted by swanlefitte Quote
A few things. There are sharpness settings in camera, try changing it to fine. .
I found that, eventually. So, um... why?? I don't understand the point of having your camera able to take sharp or sorta-sharp pictures. Presumably you want it to shoot as sharp as possible anyway...? In those settings there's a little dotted slider menu thingie... plus and minus... there's a green dot above the -1 setting; the selection bar is green there but yellow elsewhere....? (Just had a skim through the manual.... all I found is that "image outlines can be captured with more detail." Um, ok...)

QuoteOriginally posted by swanlefitte Quote
Now that I see the pictures on the big screen it looks like the lens might be back focusing, the top of the big head looks sharpest instead of the face.
I wanted to say I looked at your flickr stuff and enjoyed them. As a kid I loved View Master the same way I enjoyed your photos.
Thanks Your kiddle is cute. I have a couple somewhere. Never thought of taking pictures of them when I was the age to play with them!

QuoteOriginally posted by Audi 5 cyl Quote
I would advise you to just take whatever lens made you happy with your k1000,
My much-loved 35-105 with the macro range. As I mentioned, not so hot results there too.

QuoteOriginally posted by victormeldrew Quote
Also, you are using a high-ish ISO in the first image...would you have used 800 film if you wanted sharpness?
Right... P mode again.

QuoteOriginally posted by D1N0 Quote
Your depth of field (part of the picture that is in focus) is much shallower with The k-x than with a point and shoot optio because the K-x has a larger sensor, so more of the picture is going to be out of focus. ... You could also use liveview for focussing. It is more accurate (when it focusses where you want it to).
I wondered why there was such a DoF difference. Yes, maybe try live view.

QuoteOriginally posted by Wheatfield Quote
Cameras are only as sharp as the lens and the user.
Aaand, I was just going to post thanks for everyone's kind efforts to help. I mean, why even. Smh.


QuoteOriginally posted by marcusBMG;:
In the exif it says "resolution 600x900". Am I to understand that you were using a low resolution on the camera settings? It is difficult to diagnose from resized pics.
Not sure what you're looking at? I didn't re-size anything.

So OK, tried my SMC-A 50mm 1.4. It's been in storage since a dear friend gave it to me cos I prefer my zooms. Some of the results were better. Same gloomy lighting -- another cloudy day but I thought it good to compare in the same conditions. Haven't fixed lighting or done any processing here either.
(Now I can't get the picture to show in the thread. I used the little "link" box.)

https://www.flickr.com/photos/42816058@N05/29488227953/in/dateposted/

Thanks for the suggestions. Looks like I'll have to try the 50mm more.
There seems to be a difference of opinion about whether it's front or back focusing, if that is the case. How would this be addressed? I mentioned finding some info in my OP but it wasn't too helpful.

Last edited by Alliecat; 10-04-2016 at 12:16 PM.
10-04-2016, 12:13 PM   #22
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QuoteOriginally posted by Alliecat Quote
So OK, tried my SMC-A 50mm 1.4.
yep that looks great - the dolls are tack sharp. What f stop was that?
. A bright cloudy day is actually near ideal for portrait photography - sunlight is too harsh.
10-04-2016, 12:17 PM   #23
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QuoteOriginally posted by marcusBMG Quote
yep that looks great - the dolls are tack sharp. What f stop was that?
. A bright cloudy day is actually near ideal for portrait photography - sunlight is too harsh.
f8. I like cloudy-bright too. It's really hard to photograph pale dolls in the sun -- their faces bleach right out! But this was just gloooomy

10-05-2016, 09:46 AM   #24
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QuoteOriginally posted by Alliecat Quote
...There seems to be a difference of opinion about whether it's front or back focusing, if that is the case. How would this be addressed? I mentioned finding some info in my OP but it wasn't too helpful.
First you want to know if your AF system is front focusing, back focusing or just frustratingly inconsistent. I think this is easier with boring methodical test photos because you can set up the test so the point of focus is much more visible. If none of the below stuff makes sense to you, look for threads in the DSLR section for cameras with user-adjustable focus, like the K-5. The ideal testing setup will be the same to identify problems, you just have to work harder to make the adjustment.

Set the K-x so it only uses the center focus point. The K-x doesn't have a lot of points but you want to know which point the camera is using. Set the lens aperture to the lowest f number. That's to make the depth of field as small as possible, to make the point of focus more obvious. A tripod helps a lot for repeatable results. The color temperature of the lighting will affect results somewhat - you want lighting that's similar to what your real shots will use. Daylight is better because it eliminates potential problems with fluorescent flicker or other artificial light quirks.

Then you need a target for the AF system to focus on. That should be a high contrast detailed subject. I like to use newspaper text shot at an angle, so the top of the page tilts away from the top of the image. It's got contrast so the AF system locks on to it in a predictable place. It's got small detail. The angle means that only one line of text is the right distance away from the AF sensor. I can remember the line that was in the center of the frame when I look at the photo later. The newspaper text works for even my creaky old *ist DS, as long as I don't try it in high wind.

The newspaper text will underexpose but that doesn't matter a lot. Adjust if it bothers you. You can raise ISO to get a faster shutter speed to eliminate camera movement problems, but it is better to use a tripod if your shots have so much noise that the point of focus is less obvious. If you use a tripod, use the two second delay on the camera, which automatically disables SR. The 18-55 doesn't have a huge aperture so the depth of field is bigger than you'd like. The point of focus is not as obvious. Try to set up your test so that you are fairly close to your test subject.

You should be able to get some test images where you can say for sure that the camera should have focused exactly HERE and see where the focus really was. If it's off, then maybe further tests to see if it's off at certain distances, one particular lens, certain light, inconsistently off or whatever. A measurement of how much it's off will help if you try to adjust the AF system.

I have only read about the adjustment so I'll leave that advice to someone else.
10-05-2016, 07:24 PM   #25
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Thanks for taking time to explain all that! It sounds pretty straightforward and your newspaper is an excellent idea. I'd thought about doing "boring test photos" but wasn't sure what to set up as a target. When I have some time to tinker, I will try it. SR is already disabled because I read somewhere about that causing some unsharpness. But can use the timer anyway.
Appreciate the help
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