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04-07-2010, 08:27 PM   #16
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Ok, here goes...
I've shot over 4000 pictures since I got my k7 about 4 months ago. I'm probably overreacting about this sharpness thing, but I'd like to know for sure. I went through most of my photo's looking for what I thought would convey best to you guys what I'm having issues with. There are a lot more, but I'm just going to try three. I hope I don't mess up anyones computer. These are JPEGS but still fairly large files.

Well I tried twice. I'm doing something wrong. I hit attach, browse, and selected the jpegs I wanted to upload, but it just sat there for a long time. I'll try to upload just one for now.

Still isn't working. Error message about a token. I'll try again tomorrow.

04-07-2010, 08:35 PM   #17
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If you can't get the forum upload to work, open a free account with flickr, photobucket, picasaweb, or soemthing like that then uplaod your picture there and link to the images here.

Ideally, you'd include the full image as well as a 100% crop of the place where the focus was. EXIF information intac,t or at least post all relevant info (focus mode, aperture, shutter speed, and SR status especially). I'm reserving judgement until I see the pictures, but I have to say, I too find it extremely unlikely that any problem you are seeing could be a fault of all the lenses you have. The common denominators here are you and the camera...
04-09-2010, 09:56 AM   #18
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I put a couple on my flickr page, but they are not expandable. You can't zoom to see the problem there. I'll figure something out.
04-09-2010, 03:37 PM   #19
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QuoteOriginally posted by Snydly Quote
I put a couple on my flickr page, but they are not expandable. You can't zoom to see the problem there. I'll figure something out.
If you post a link or tell us your name on FLICKR we can have a look.

04-09-2010, 03:51 PM   #20
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QuoteOriginally posted by Snydly Quote
I put a couple on my flickr page, but they are not expandable. You can't zoom to see the problem there. I'll figure something out.
You should upload the same files that you are unhappy with.

What are the pixel dimensions of the files you are viewing that are "not sharp", and what is the resolution of your monitor screen? Do not forget , you cannot "zoom" an on-screen picture to beyond the resolution of your screen without getting pixelation.

Again we need to see the pictures to help you.
04-09-2010, 04:21 PM   #21
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It could be that you are looking at the shot at 100% and just expect far too much out of it. Please post something so we can see. Or print a few images so you can see.
04-09-2010, 06:12 PM   #22
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QuoteOriginally posted by Snydly Quote
I just don't think any of them are very sharp.
Snydly, your inability to upload 100% crops tells me that you don't have aquired full experience in all aspects of photography yet (nor did I).

So, let me speculate about your problem (and w/o samples, it is speculation).

First, it is extremely difficult to have the one photo which pops at the 100% level. I have quite a few so I know that the K-7 is capable of it. But IMHO, it is impossible to plan ahead for a photo which pops at 100% except if you fully control the light. Sun light is not enough. Studio flash may be able to provide the satisfaction you are after. Really try a couple of flash photos to start to get an idea about the difference. Simple flash shots may be boring though. Popping sharpness at 100% is less desirable as it seems. But it is a cool thing of course.

Second, in most shots (esp. if you have a short enough exposure time to freeze the action and avoid motion blur and have ISO 100) the depth of field is too narrow for 100% popping sharpness. The AF (or even Liveview) isn't accurate/fast enough and meant to bring the focus into the depth of field only. But for 100% popping sharpness, your circle of confusion is only 1/4 the size of conventional depth of field. One way may be to make many shots and select the lucky one.

E.g., even at f/8 with 50mm and 2m subject distance (head portrait), the focus precision must be 97% (6cm permissable error). The focal lengths at 2.00m and 1.96m are 51.282 and 51.309mm resp., i.e., the lens tube positioning precision must be better than 27Ám! This level of precision is very hard to achieve as the mechanical play is larger than this normally! And assuming a half turn of the focus ring from 45cm to infinity, this is a focus ring turn of about 3/4░ only!

Third, the Bayer sensor + AA filter have non perfect MTF near the Nyquist frequency. So, in all photos you see which pop at 100% resolution, a good amount of contrast enhancement and sharpening was applied in post-processing. Which is ok.

The lens' resolution is your least of problems. In the center at f/8, most lenses outresolve the sensor.
04-10-2010, 02:18 PM   #23
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Let me try again...

It keeps timing out and saying it failed most likely due to a security token...

?????

I give up. Thanks for all your suggestions and help. I'm actually pretty good with computers. I've written software to do just this in the military. Maybe it's because I haven't been a member long enough. I read recently that someone stated he was 'finally allowed to upload pictures'. Maybe I'm too new. I selected the paper clip up there, hit browse, selected the picture and an upload window and progess bar appears, but every time I get the same error code.

Try this...

Flickr: S. Whiplash's Photostream

I don't know why that doesn't show as a link, but I checked it and if you copy and paste it, it should get you to my flickr page.

Thanks again...


Whoa, I'm editing what I just posted...

It DID show up as a link after all. You can't get the data from the camera though. I'll look it up and post it here.

On the bird picture you will see what looks like a 'P' near the middle. Took me a while to figure out what that was. Apparently I had something on the sensor. I tried blowing it out several times. Even put a vacuum cleaner near the mount and I think that got it. Kind of ruined a lot of pictures until I was able to remove it.

Okay, second edit. Looks like you can get the photo data on flickr. Anybody know how to blow up the photo's?

I'll do a crop on Photoshop and post them on flickr. Thanks for sticking with me...


Last edited by Snydly; 04-10-2010 at 02:25 PM.
04-10-2010, 02:50 PM   #24
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Looking at the shots you have psoted, the bird is not in focus and/or your shutter speed wasn't fast enough. The surfer shot looks just fine. Neither indicate any sort of cameraor lens problem.
04-10-2010, 08:40 PM   #25
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QuoteOriginally posted by Snydly Quote
On the bird picture you will see what looks like a 'P' near the middle. Took me a while to figure out what that was. Apparently I had something on the sensor. I tried blowing it out several times. Even put a vacuum cleaner near the mount and I think that got it. Kind of ruined a lot of pictures until I was able to remove it.
Of course I like it better to not to have dust on my sensor but it's pretty easy to fix it in Photoshop with the Clone Stamp Tool. Or in Lightroom. So don't throw any images out just because there's dust spot(s) on them. For me it's seems impossible to keep the dust away from the sensor. So it's clone stamp/rocket blower time pretty often around here

The surfer pic looks actually quite good (at least in the 1024px width you posted) I can see small water droplets in the air around surfer.

And remember that the images people post here are usually the best ones they have. And possibly PP'd to the max with a little added sharpening here and contrast there. And everybody have a lot pics they don't post here because they have missed focus etc.
04-10-2010, 09:54 PM   #26
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QuoteOriginally posted by ovim Quote
The surfer pic looks actually quite good (at least in the 1024px width you posted) I can see small water droplets in the air around surfer.
Thanks... I guess maybe I'm being too critical. When I zoom in (100%-200%) in picasa I see fuzzy borders between colors. Maybe that's normal. I'm just amazed at some of the photo's you guys take, and am trying for similar results. I've still got a ways to go with PP...

The surfer pictures taught me other things about photography. I took one of my boys to school that day, stopped at the beach just to breath the fresh air, and was stunned to see these waves. Normally Cocoa Beach is knee-waist high, but this day was a treat. I always carry my camera with me now, just for such an opportunity. I snapped about 200 shots that day. I have other ones that are MUCH better, but you can tell who the surfers are, and I read that you couldn't use a photo with an identifiable person without a release. I'm probably going to darken the people in a couple and see if the local surf shops want them. What it taught me though was to be thinking about the whole shot. I wanted the apeture as small as possible, but couldn't sacrifice the speed. I was so rushed (excited) I forgot about the ISO for a while. I didn't shoot any RAW either, which I understand gives you more to work with later. I tried a 2x extender for about 50 shots, but they turned out terrible. I didn't use any burst, or tune the WB (it was cloudy) either. All in all I feel lucky to have been at the right place at the right time, but also a little dumb for not getting everything right. These gifts are rare...

Thanks again all...
04-11-2010, 03:07 AM   #27
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QuoteOriginally posted by Snydly Quote
Thanks... I guess maybe I'm being too critical. When I zoom in (100%-200%) in picasa I see fuzzy borders between colors. Maybe that's normal.

You cannot judge a picture by looking at anything larger than 100%. You just get pixelation. Most pictures are not viewed at anything near 100% view.
04-11-2010, 03:19 AM   #28
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Download a pic you admire for sharpness, and do with it what you do with yours, and see if there's a difference?
04-11-2010, 04:02 AM   #29
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I have checked out the shots and the surfer one looks in focus and crisp. The next step is for you to read up on Sharpness post-processing, since all images can benefit from this. Generally I apply two levels of sharpening, but both are subtle. It is so easy to over-do it.

But besides sharpening there are other ways to get your images to have more impact. One of these would be to use a polarising filter, especially useful at the beach.

This article of mine might help: Your Photos -- From Washed Out To Punchy.
04-11-2010, 04:57 AM   #30
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QuoteOriginally posted by Snydly Quote
When I zoom in (100%-200%) in picasa I see fuzzy borders between colors.
A 200% view might be useful for image manipulation at pixel level, but it isn't useful for evaluating sharpness. At 200%, one pixel in the original becomes four pixels the displayed image. Of course, you cannot expect a sharp image.

Even a 100% view of a sharp image will not be as sharp as you probably expect it to be. Note that with the exception of Foveon sensors, most sensors use a Bayer array which captures only one of the RGB components for a pixel at each pixel position. A 10 megapixel Bayer array sensor should rather be called a 10 megadot sensor (where three dots are required to created one RGB pixel).

Please read about Demosaicing, you may have to adjust your expectations about sharpness at 100%.
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