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Old Mar 19, 2009, 1:40 AM   #1
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I need some input on how to shoot this better, what adjustments to make or whatever might work (may even need specific tips from a Pentax K200D or K20 user), since not a one of these shots came out like I expected. I was trying to get a shot of a kildee and I was at maximum zoom. Although I had changed the AF focus point to the center (off auto select, where the camera auto chooses focus points) and the focus mode to AF.S (so I could also do any fine manual focusing, which was necessary in each shot of this bird I tried)...but although this one wasn't so bad, it still showed up blurry although in the viewfinder it looked perfectly sharp (the bird) and I got a focus lock indicator, telling me the Pentax K200D thought it was focused. So here are the specific settings:

ISO 100, 1/250 sec, f/10, 300mm (on a Pentax K200D, Pentax DA 55-300 mm lens). light metering center-weighted. What you see here is the Pentax-saved DNG> cropped PNG > 95% saved JPEG quality, with DP Review's recommended sharpening of unsharp mask @ 80%, radius 1 for RAW files (if anyone can recommend a 'better' sharpening setting inside Photoshop, please share).

Although I easily did 6-7 shots of this one bird, although all of them appeared focused with the bird in the viewfinder, I'm miffed as to why it still looks so blurry. I read in the manual that it said AF might have trouble with low-contrast items and MF could be necessary (which I did). I also remember that with the lens in question, it's sometimes recommended to use at least f/8 or better at 300mm, better being closer to f/11. On other shots I tried at f/11 or even f/13..same result--blurry bird!! All shots were done mounted with a tripod, some with IS off (since the manual recommends that when camera is on a tripod), some with IS on (I've never noticed a difference with it on or off even when IS is on when the K200D is on a tripod)...so is it possible that although I'm sure the tripod didn't move that despite IS being on that perhaps it's one of these two problems:

1) Problems focusing because of low contrast between bird and background or
2) Even with IS on, it's still possible to have the camera 'shake' enough even with a pretty gentle touch on depressing the shutter?

Or is it something else?

Any other tips on general rule-of-thumb settings for aperture when at maximum zoom like this, with this lens? Of course if anyone can say definitively how I could have gotten this kildee in focus...I'm dying to know because I'm really scratching my head over this! I've taken shots of the moon at 300 mm and gotten perfectly sharp images with IS on and off when mounted on a tripod and I even took pictures of a big brown rock and a large branch submerged at that pond which was perfectly sharp even on MF @ 300 mm (like the rock was also). I really can't figure out what went wrong--although I've had a similar problem with shooting a mockingbird (I assume because of it's largely grey body) and only when I backed off from 300mm to 260mm did I get a focus lock AND and sharp picture.
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Old Mar 19, 2009, 12:59 PM   #2
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AF pointsettothe center, auto off, and AF.S...Actually these are my defalt settings! 1/250 for 300mm sounds a bit slow, but considering the camera was mounted on a tripod no worries hereimo! I also tried with IS on and off and detected no diffrence when on tripod.
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Even with IS on, it's still possible to have the camera 'shake' enough even with a pretty gentle touch on depressing the shutter?
ISworks greatfor vibrational shake but does not quite work for motional shakeaccording tomy humble experience, which might becaused bydepressing the shutter. I know you can't shoot birds at 2'' shutter delay! Howeveryou may try a higher but still a safe iso for image quality, say320 or 400, to increase the shutter speed for comparison.I'd also like to see the uncropped picture with exif. Nothing seems to be in focus here. I had to return a lens last year due to decentering issue. Anyway, I'm sure you can get someueseful feedback should you apply Pentax/Samsung dSLR forums also.

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Old Mar 20, 2009, 12:30 AM   #3
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A couple of things came to mind when I saw your post in the Pentax forum, but your explanation here rules out my first thought which was the dioper adjustment on the viewfinder had gotten knocked off of where it should. While it will definitely cause a subject to appear in focus when it's not, you won't get a focus lock indicator if the focus point is properly over your subject.

Looking at your picture, I agree with bahadir - nothing is in focus. Is this full frame or did you crop?

My own experience with this lens is that it's soft at 300mm, even at f11. If you are interested, let me know and I'll post some 100% sized crops (or the whole file) of a yew or something like that taken wide open, then stopped down to f11 and f14. But I think my f11 isn't as blurry at yours.

As far as sharpening, I use two "passes" if you will for sharpening. First I'll use the settings of 0.3 radius (what I used for the K10, 0.1 for the K20, so you might try in that range) and 120-180%, depending on the picture. It's really not as much as it sounds because the radius is so small. I also usually use smart sharpen for this. Then I'll use USM set to radius 50-55 and amount to 10-15%. That doesn't add much sharpness, but does add some extra contrast.

However, I don't think those settings will help your picture enough to make it satisfactory.

I also agree that using a shutter speed of over 1/300 helps, even with IS. I'm not as steady as I used to be. However, it seems to me that IS on a tripod does make a slight difference - or so it seemed Sunday. I don't normally use a tripod except for indoors, where I think about turning it off. Sunday I was out shooting wildflowers with the tripod and forgot most of the time to turn it off. The pictures seemed softer than normal to me.

I've also had a decentered lens. Have you ever noticed one side being fuzzier than the other side, when there was no reason for it to be? That was the first thing to show up on my broken lens.

As far as whether you can cause camera shake just from depressing the shutter - absolutely! Even with IS on! In fact, I sometimes think that IS has hurt my shooting skills - every so often I'll notice that I'm moving the camera slightly when I push the shutter. This is unlikely to be a problem if you have a sturdy tripod though.

You might want to go shoot a brick wall (or a chain link fence, like I did) at various focal lengths and various apertures to see if the problem is with the lens or not. And let me know if you are interested in Monday's test shots taken with my DA 55-300. If my pictures seem significantly sharper than yours do at the same focal length/aperture, then yours might need repair.
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Old Mar 20, 2009, 2:36 AM   #4
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Well, given the fact the restriction for posting photos in here is that the longest side can only be 750 pixels long, I took the full shot and cropped right around the middle of the .png, then to get it under the 240K attachment limit, I saved it @ 95% JPEG quality. That said, the pic here looks the same as the full one I processed the RAW from. I had a lot up there, but I went DNG > Unsharp mask @ 80%, 1.0 radius > save PNG > crop > save @ 95% JPEG.

From what I saw during some of my shots today, I saw some shake in the viewfinder when the wind from the vehicles off of the highway hit me and the camera on the tripod, and the lens was @ 300mm. :shock: I'm going through those shots and seeing if those came out focused...although the ones I've checked so far look kind of soft where I focused on, with the rest seemingly as out of focus as this bird (no one side at the left or right of center seems any worse than the opposite side).

I'll finish looking at the rest of them and if those came out well, I guess I can chalk this shot and any other out-of-focus ones like this to sufficient camera shake to cause the overall blur?
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Old Mar 20, 2009, 4:08 AM   #5
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Not looking good. I tried to find some decentered lens shot examples and while mine doesn't appear to be to one side...it's kind of all around it appears. Since I found some examples that said trees were a good way to tell of the 'smearing' decentering does, I'll go back through my pics I finished processing and try uploading 3-4 to Flickr then post the links here. I'll save resave the png as jpg but full frame. I'll include the kildee shot as one of them. Looks like I'll put two goat shots, the kildee and one other I'll try to think of that has a tree or some way to easily identify decentering. If that's what it is (decentering), please *someone* let me know so I can call the place I bought it from and get the RMA going first thing before noon tomorrow.

After looking at all of these, I find it hard to believe it's camera shake, as I can't really see a one that's as sharp as it should be (except for what's in the very center). Jeez...I was so hoping to take some more pics tomorrow.
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Old Mar 20, 2009, 5:30 AM   #6
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Here's 5 different shots for consideration of whether the lens is most likely decentered (something's badly off, I think...I don't think it's possible I messed up EVERY shot the same way with a tripod and soft press on the shutter).

Of course Flickr didn't help me any either...but after a lot of YAWN and :P, here's the link to the 5 pics:

http://www.flickr.com/photos/2781920...426489/detail/

I hope that's enough variety in aperture and focal length to be conclusive one way or the other. I'm not feeling good about it from the 'smear' decentering is supposed to produce. :'(
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Old Mar 20, 2009, 2:04 PM   #7
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Can someone who can tell me for sure if it's a decentering issue please chime in (I know someone will eventually, but I'd like to get a surefire conclusion in the next hour, since the retailer has said I should pack it up and ship it back for exchange). I'm new to even knowing about a 'de-centering' issue so I have no clue if that's what I'm seeing (since so much more than just one side of center is out of focus despite the camera telling me each time it focus locked and therefore should have been in focus)...
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Old Mar 20, 2009, 2:53 PM   #8
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I haven't looked at the new set, but if your vendor is willing to take it back but you don't have time to full research the problem, exchange it regardless. Then you'll have time to make a decision if what you are seeing is the lens characteristics in general or your old one. So ship it out now, then lets look.
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Old Mar 20, 2009, 3:02 PM   #9
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Cool. I'll do that, but I did get some more test shots of a brick wall. Uploading to Flickr right now. Took 7 from Iso 100-280; F 5.6-13; 98-300 mm. Will comment on each in Flickr. IS was off, mounted on Manfrotto Bogen 055xb tripod with 322 RC ball head. Everything seemed secure and locked in place.

"Workflow" (don't like the word, but it seems efficient)

1) Open in Abode camera RAW, sharpness 0 (remove the 25, recommended by DPReview)

2) Open in Adobe proper and unsharp mask @ 80%, radius 1

3) Saved as PNG then batch converted to JPG at best quality (100%) by Infranview

Will post link (edit this post) once I've commented on the pics there with respective iso, aperture, mm, shutter.

Well...I was up the whole night researching the problem, trying to find de-centered lens pic examples. Mine don't seem to be just blurry or smeared to one side only--only the center appears close to focused and most of the rest seems nearly or completely blurry despite having a focus lock on both AF and MF with the shots previous to these brick shots. I'll post the link and have it edited here w/n next 10 mins.

EDITED/ADDED @ 15.13 CDT

Here's the link that includes the brick test shots:

http://www.flickr.com/photos/2781920...426489/detail/
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Old Mar 20, 2009, 3:22 PM   #10
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I took a quick look at your flickr album thanks for posting them as they are much more helpful.

I'm nothing but an amateur at photography so I don't know all the ins and outs. A couple of thoughts from your pictures - looking at the full frame kildeer - you are cropping so heavily, the bird was at such a distance, and you are using a consumer zoom instead of a high quality prime, it's not surprising that the shot isn't razor sharp. You'd have to take a huge jump in lens quality and also preferably more mp to help with the cropping to get razor sharp. And I really like your secong goat picture - the bokeh is quite a bit smoother than what I get from my DA 55-300. But having said all that, I looked at your brick wall pictures - my opinion is that they are overall softer at similar focal lengths/aperture settings than mine were (shooting a chain link fence). They make me want to shoot a brick wall with mine to see if there's as much barrel distortion (something I haven't otherwise noticed) with mine in addition to the softness.

I'd definitely exchange it since you have the opportunity.
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