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09-18-2019, 05:53 PM   #16
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QuoteOriginally posted by Jnm Quote
....yes, it would be helpful to know the proper way to do a full resolution crop.
Have a read here:
How to upload / link photos - BEGINNERS START HERE - PentaxForums.com

As you can see, if you review that forum page, the forum resizes your images to 1400x900 if they're larger than that. So, if you want to show a full resolution image, either host your images on a different site where you can post a full-resolution image, and link to there in your post here, or, crop a 1400x900 portion of your image here, so that members can see your image in it's full resolution in order to comment on the technical aspects of the photo.

You can use any photo editor to crop a 1400x900 pixel portion of your image.

09-20-2019, 12:23 AM   #17
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09-24-2019, 10:28 AM   #18
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QuoteOriginally posted by BigMackCam Quote
Hello and welcome to the forums

Would it be possible to post photos demonstrating the issue? Ideally, the full photo resized to fit here, along with a 100% crop of the subject you focused on, and settings or EXIF data. Plus, the same for one of your photos where the focus was accurate. Seeing actual photos will help us to determine if it's a focus, shutter or motion blur issue, or something else.

AF fine tuning can be important when shooting through the optical viewfinder, but is irrelevant in Live View where contrast detect via the sensor is used.
Finally I am home and can post the photos as requested for my AF problems. thanks for the many offers of advice and suggestions!
The Tower pic was taken on a tripod at dawn. Out of focus. here are the specs:
M Mode, LV, 1/160, F11 26,25 mm 800 ISO I was focussing on the tower but also wanted to get the dramatic clouds at the side so used a wider aperture. Never noticed the plane until after the shot!

The ball pic: 1/320 F 5.6 55mm 400 ISO This would seem to be in focus.
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09-24-2019, 11:59 AM - 1 Like   #19
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QuoteOriginally posted by Jnm Quote
M Mode, LV, 1/160, F11 26,25 mm 800 ISO I was focussing on the tower but also wanted to get the dramatic clouds at the side so used a wider aperture. Never noticed the plane until after the shot!
The answer is with the lens. While I am a great fan of the DA 18-55/3.5-5.6, my copy has only been paired with the K-3 a few times in the last five and a half years. Its resolution is simply inadequate for use with the 24Mpx sensor. Focus for the shot using CDAF in live view was probably as good as was possible given available resolution and low contrast at that time of day. That said, I don't believe it was significantly off and place the softness on the lens and light.


Steve


Last edited by stevebrot; 09-24-2019 at 01:56 PM. Reason: wrong word
09-24-2019, 02:00 PM   #20
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QuoteOriginally posted by stevebrot Quote
The answer is with the lens. While I am a great fan of the DA 18-55/3.5-5.6, my copy has only been paired with the K-3 a few times in the last five and a half years. Its resolution is simply adequate for use with the 24Mpx sensor. Focus for the shot using CDAF in live view was probably as good as was possible given available resolution and low contrast at that time of day. That said, I don't believe it was significantly off and place the softness on the lens and light.


Steve
I agree with Steve about the lens! The lens will get you by but will never be called "tack sharp"
You can help it out in post or bump up the sharpening/contrast in camera (if shooting jpeg). In the photo with the ball, the ball looks good (probable close to its apex point) but the foot looks a little soft. I think this could be caused by motion blur from the foot. Even though you shot it with a moderate SS it was not enough to freeze the motion completely.

I am not able to see the other photo you refuted to but if it was shot with the same lens you can probably expect simulate results on sharpness even at the lens's best f: stop

Best of luck!!!

PS. I would say looking at photos on your 24+ monitors or zooming in on your handheld devices can created a lot of anxiety over sharpness. I suffer from the pixel peeking syndrome myself 😢

Last edited by Photobill; 09-24-2019 at 02:08 PM.
09-24-2019, 07:50 PM   #21
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Welcome to the forum, I’m the worst person to comment on AF... enjoy your photography once you get it sorted.
09-25-2019, 04:18 AM   #22
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QuoteOriginally posted by stevebrot Quote
The answer is with the lens. While I am a great fan of the DA 18-55/3.5-5.6, my copy has only been paired with the K-3 a few times in the last five and a half years. Its resolution is simply inadequate for use with the 24Mpx sensor. Focus for the shot using CDAF in live view was probably as good as was possible given available resolution and low contrast at that time of day. That said, I don't believe it was significantly off and place the softness on the lens and light.


Steve
thanks very much Steve for your analysis. In a way, it's reassuring to hear that it depends on the lens and not on my inexpertise!! what can I do about this? Is it possible to buy non Pentax lenses with better resolution? It's ironic to think that 5 yrs ago the reason I switched to Pentax K30 from a Konica Minolta, which still works fine, is because it only had 12MP sensor (being 11 yrs old at the time and then also being discontinued as a brand)!!


I have a 50-200, a 50 prime, the 18-55 all Pentax and a macro Tamron 90m. I seem to have the same problem with them all so I'm inclined to believe what you say. Is there a solution or should I just sharpen as best I can in PS and resign myself? Yes I am a guilty pixel peeper and look at zooms larger than x8....
09-25-2019, 04:52 AM   #23
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A question that came to me when reading through this... is it a RAW file or JPEG that you're talking about/you've uploaded here?

If it's a JPEG, have a look into 'Extra Fine Sharpness' for JPEG settings. The default setting is not the 'fine' or 'extra fine' sharpness setting so it can come across a little bit softened. I've found this to have the biggest impact on straight-out-of-camera pictures (albeit on my K-70).

Similarly, for RAW pictures, there's no sharpening or softening added whatsoever as there's no processing of the image. I.e. unless you sharpen it a little yourself, you can have some seemingly soft stuff there unless you take time to address this yourself.

Edit: Wrote some spiel about focussing using LV but you've absolutely addressed what I had written.
For what it's worth, the non-zoomed image looks nice. Bear in mind you've zoomed quite heavily into the tower so it might not be super sharp, and same goes for it being at ISO 800 as this will have some effect on image quality.

Let us know how you get on with the above!

09-25-2019, 02:41 PM   #24
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QuoteOriginally posted by Jnm Quote
I have a 50-200, a 50 prime, the 18-55 all Pentax and a macro Tamron 90m. I seem to have the same problem with them all
So your problem is not about defective AF. And it's not about the resolving capacity of the lens - the Tamron 90 is one of the sharpest lenses out there. (I don't know which 50mm prime you have, but most of them will also provide plenty of resolution.) And it's not about the camera - if you can't get the high quality images you seek with the KP, switching to another camera isn't going to work. The issue is about technique. And light.

Take your landscape at 26 mm, 1/160, F11, 800 ISO. If you were shooting on a tripod, that's good. Focusing with LV is good. I assume you used a remote shutter release or the self-timer, with SR off. With the KP, you could also use electronic shutter to avoid shutter shock. You could also try pixel shift with MC for maximum resolution (it uses electronic shutter too). So why 800 ISO? You could have got the same exposure with f8, 1/40th 100 ISO or with f8 1/80th 200 ISO or f11 1/40th 200 ISO. If you were worried about the waves showing motion blur, well they do anyway - so why not do a long exposure and blur them properly? It would be a much more interesting photo.

DOF can only do so much. If you really want to get landscapes that are sharp front-to-back, try focus stacking.

If you want more resolution, take a series of images with the Tamron 90, process them (matching exposure and WB between the shots) and stitch them together. (The free program Microsoft Image Composite Editor does a good job and there are many others.)

In my view, the main problem with that shot is not the resolution or the focus, but that it is just dull (in both senses of the word). There isn't a strong foreground. The composition seems lopsided to me. The foreground sand and the sky at the top add nothing to the image - it cries out for a 16:9 crop. And since the only interest in the centre portion is the reflection of the cloud on the water, that needs to stand out. The whole image lacks contrast. The light was not only too low, but it isn't particularly striking.

If you shot in RAW, you could do a bit with it. What I would do is:
- straighten the horizon
- crop to 16:9
- use a warmer WB
- increase the clarity and microcontrast in the sky
- increase the overall exposure a bit
- tone map to increase the contrast - raise the highlights a bit and the mid-tones significantly. Shadows - try different settings.
- increase clarity on the tower
- add vibrancy and maybe a little more saturation

But an image like that is only ever going to be a snapshot. The light was uninspiring. Even with a sharper lens than the 18-55, you wouldn't have got a huge amount of resolution on the tower.

The problems you are facing aren't really about gear at all. That is the classic novice error - and as long as you think that buying a different lens or camera will fix things, you will not be happy. To improve your photos, you need to work on technique and pick where and when to shoot. The positive about this is that it's fun to learn and if you work on it you will start to see improvements. That can be quite satisfying.

There's plenty of good info available about landscape photography techniques. Start by getting a handle on hyperfocal distances.

Enjoy.

Last edited by Des; 09-25-2019 at 07:06 PM.
09-25-2019, 04:26 PM   #25
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QuoteOriginally posted by Jnm Quote
thanks very much Steve for your analysis. In a way, it's reassuring to hear that it depends on the lens and not on my inexpertise!! what can I do about this? Is it possible to buy non Pentax lenses with better resolution?
I think the suggestion was that the problem you're having is with this particular lens, the 18-55mm, not with all Pentax lenses. It is therefore possible to buy better Pentax lenses, and, of course, there are some non-Pentax options too.

QuoteOriginally posted by Jnm Quote
I have a 50-200, a 50 prime, the 18-55 all Pentax and a macro Tamron 90m. I seem to have the same problem with them all so I'm inclined to believe what you say. Is there a solution or should I just sharpen as best I can in PS and resign myself? Yes I am a guilty pixel peeper and look at zooms larger than x8....
If you're experiencing the same problem with all your lenses, then there may be another issue. I'd suggest posting images shot with those other lenses here and then members can help you determine if the fault is with all the lenses, with the camera, or with the person behind the camera.
09-25-2019, 06:19 PM - 1 Like   #26
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QuoteOriginally posted by Jnm Quote
The Tower pic was taken on a tripod at dawn. Out of focus. here are the specs:
M Mode, LV, 1/160, F11 26,25 mm 800 ISO I was focussing on the tower but also wanted to get the dramatic clouds at the side so used a wider aperture. Never noticed the plane until after the shot!
The Tower shot, I just take a late sunset shot similar to the lighting you have here. Handheld using DA21 limited and manually focused at the advertising sign on the right hand. [ISO200, 1/10 sec, f5]
So I will offer my 2 cents on that photo. Note that I am on a K3 and I donít have the zoom you are using.

Focusing,
I would magnify the Live View to 100% (On K3, I hit the LV button to turn on Live View and OK button to do the magnification.) then ďmanual focusĒ at the object you want to focus which is the tower. Regardless of my very bad eyesight, magnifying the live view can help. If you want to do handheld, donít turn on the self-timer so that the SR can help you.

The setting,
I would use the lowest ISO possible without underexposing it. I would try to get my ISO down to 200 or no more than 400 (that is on my K3, but I hear that KP has a lot better high ISO performance.) Give your camera more light by using an f-stop of 6 to 8 and shutter speed of 1/20 (stand steady, hit the shutter button while exhaled, etc.) And take more than one image with a bit of different setting to find the best combination. Donít forget to shoot raw (.dng) then work a bit more in post-process.

Lens,
Is it a kit zoom? I donít have the lens, so I donít know if it is because you have a bad lens or something else. Pentaxís limited or pro-level lenses have no problem capture good image. I see you use 26 mm for that photo, so the lenses like DA20-40 or DA 21 limited are a good candidate. It is too late to say now but when buying a camera, skip a kit zoom. The money will be worth spending on a limited prime, IMHO.
09-25-2019, 07:57 PM   #27
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QuoteOriginally posted by tokyoscape Quote
Is it a kit zoom? I donít have the lens, so I donít know if it is because you have a bad lens or something else. Pentaxís limited or pro-level lenses have no problem capture good image. I see you use 26 mm for that photo, so the lenses like DA20-40 or DA 21 limited are a good candidate. It is too late to say now but when buying a camera, skip a kit zoom. The money will be worth spending on a limited prime, IMHO.
Yes the 18-55 is the kit lens.
09-26-2019, 08:43 AM   #28
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wow, pretty brutal analysis of the photo, Des. However, I'm here to learn so constructive criticism does not faze me. It's not the gear that makes a "good" photo --obvious-- however, if a contributor tells me that he never uses the kit lens and that the resolution of this lens is insufficient for the KP sensor, that it will never render tack sharp....? The tower image is a raw file straight out of the camera, no processing, no cropping, which routinely I do. I just resized it to jpeg in order to post so that I could illustrate the lack of focus problem that I was having with this lens in particular. Recently on a photo tour I was told "Don't be afraid of the ISO, with modern cameras the noise is not such a tragic issue". The light was poor so I upped the ISO.
Another question I have: in LV I see the focus point in green whereas using the viewfinder, it is never green but always red. Is this an indication of error in focus or is this the normal indication?
I attach another image for your consideration. specs are the same as the preceding one.
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09-26-2019, 12:07 PM   #29
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I read “raw file straight out of camera”. As my earlier suggestions were overlooked, I suggested that there’s no post processing sharpening on a raw file, which would happen with an OOC JPEG.

Perhaps see what an accompanying JPEG would look like with the suggestions of EF sharpness I made earlier and see whether that makes a notable difference.
With EF sharpness I find the OOC JPEGs are great to look at with the K-70.

I agree, 800 ISO is nothing to worry about generally, but with a tripod available you could probably push that down and increase the shutter time.
09-26-2019, 01:55 PM - 1 Like   #30
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QuoteOriginally posted by Benz3ne Quote
A question that came to me when reading through this... is it a RAW file or JPEG that you're talking about/you've uploaded here?

If it's a JPEG, have a look into 'Extra Fine Sharpness' for JPEG settings. The default setting is not the 'fine' or 'extra fine' sharpness setting so it can come across a little bit softened. I've found this to have the biggest impact on straight-out-of-camera pictures (albeit on my K-70).

Similarly, for RAW pictures, there's no sharpening or softening added whatsoever as there's no processing of the image. I.e. unless you sharpen it a little yourself, you can have some seemingly soft stuff there unless you take time to address this yourself.

Edit: Wrote some spiel about focussing using LV but you've absolutely addressed what I had written.
For what it's worth, the non-zoomed image looks nice. Bear in mind you've zoomed quite heavily into the tower so it might not be super sharp, and same goes for it being at ISO 800 as this will have some effect on image quality.

Let us know how you get on with the above!
Thanks for your suggestions. The last image I posted was processed in PS also sharpened and saved as jpg max quality. With the KP I can take raw+jpg simultaneously and my setting for jpg is max 3* setting. I am not really so unhappy about the focus in the image above even if it could be better and there's also the noise from the ISO
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