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12-31-2010, 09:26 AM   #1
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Focus problems

Was out today, took some shots with the camera on a tripod using the remote with 3s delay. Liked one, but when I look at it properly the low bushes on the right of the island are far from sharp - in fact they almost look like there are two of everything in the original. The rest is fine and sharpened up well.

The original is a PEF, I used ACR & CS4, the psd is 15 bits, the last two steps were resizing to 1024 pixels wide and then converting to an 8-bit image so I could save a JPG to upload to Flickr.

This has me foxed. Camera shake should have affected the whole image. I have stuff in front and behind the blurry area in focus (I cropped the bottom of the image and there is stuff there that's clearly OK). It wasn't windy, plus there are no leaves on the bush and at this time of year it's all last year's growth that has hardened.

Lens issue? Camera issue? Sensor issue? Shutter blur? Anything other ideas? And what should I do to narrow down what the problem is with a view to fixing it? I might end up wishing I had stuck with my E510.




12-31-2010, 09:58 AM   #2
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other environmental issue (mist, haze) really it's kind of hard for me to tell at the size ond on a cheap work monitor. I do think it is an excellent image though. How does it look printed (which is where i usually make my final judgments on an image)
12-31-2010, 10:00 AM   #3
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If you did everything right and one side of the image is blurry, the lens is probably suffered from optical misalignment which cannot be fixed. Opt for a replacement if possible.
12-31-2010, 10:02 AM   #4
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Steady on, I only took it a few hours ago! Thanks for the compliments, yes overall it's worked well, but those bushes I suspect will look hideous printed.

It was actually RAW+JPG and shows clearly in the JPG from the camera so I could post a 100% crop of that if it would help.

BTW I'm very lucky, this is less than 30 minutes drive from home.

12-31-2010, 10:04 AM   #5
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QuoteOriginally posted by wlachan Quote
If you did everything right and one side of the image is blurry, the lens is probably suffered from optical misalignment which cannot be fixed. Opt for a replacement if possible.
I *think* I did everthing right. I did what worked with the E510. So, maybe I should talk to them next week - it came from a reputable UK supplier not that long ago. Would the misalignment show all the way down that side? This image really only has detail in that one area.

I guess this is where a test chart would be so, so useful...
12-31-2010, 10:10 AM   #6
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QuoteOriginally posted by cats_five Quote
I *think* I did everthing right. I did what worked with the E510. So, maybe I should talk to them next week - it came from a reputable UK supplier not that long ago. Would the misalignment show all the way down that side? This image really only has detail in that one area.
I guess this is where a test chart would be so, so useful...
Not sure what you mean by "all the way down that side". One way to detect optical misalignment is to take 2 identical shots, with 1 the camera being upside down. Then you can compare the 2 shots with identical details. Don't be surprised if there is slight loss of details, but if the difference is too much, redo the tests and also with different scenes. Also, don't fully rely on AF which is not that accurate with wide angles. The loss of detail is also more pronounced with scenery than test charts which are difficult to use well.
12-31-2010, 10:34 AM   #7
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What I meant was would misalighment show as an isolated patch or right down one side of the frame?

Focal length was 77.5mm (from the EXIF) so doesn't count as wide angle. I will see if I can have a go at the upside down thing, though the tripod doesn't lend itself to that.
12-31-2010, 11:01 AM   #8
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This seems pretty obvious, but...ummm....were the bushes something that could have moved due to wind during the exposure, while the rest of the stuff didn't? It's pretty much impossible to say whether there was a problem without full EXIF available, as well as 100% crops, or better yet, the full size jpg.

12-31-2010, 11:17 AM   #9
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QuoteOriginally posted by cats_five Quote
What I meant was would misalighment show as an isolated patch or right down one side of the frame?
The whole side should be blurry, not just a patch. Some higher contrast targets like buildings would be more suitable for tests though as the tree branches aren't that static.
12-31-2010, 11:52 AM   #10
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As one way of eliminating some of the confusion, have you looked at the rocks around and to the right of the "fuzzy" bushes? If they are sharp, then the bushes are the problem, neither the lens nor your technique.
12-31-2010, 12:43 PM   #11
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The EXIF is all at Flickr: Exif | Bishop Hill from Burleigh Sands | Flickr - Photo Sharing!

The basics are:
Exposure 0.004 sec (1/250)
Aperture f/8.0
Focal Length 77.5 mm
ISO Speed 100


There wasn't much wind. The gliding club is the other side of the Loch and it runs a weather station, and it was showing 5 knots tops during the time I was there which is really pretty gentle. Given there are no leaves on the bushes and they are all stiff old growth at present I would expect them to be static - I didn't notice the bush near where I was shooting from moving. In June when there are leaves and new growth then yes, even 5 knots will make them wave around.

Are the rocks OK? Good question, not as easy to answer as one might expect!

The JPG from the camera is 6MB, I can upload it to Flickr as I have a Pro account, not sure you would want to download the whole thing. A selective crop or two might be more useful.
12-31-2010, 12:52 PM   #12
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QuoteOriginally posted by cats_five Quote
The EXIF is all at Flickr: Exif | Bishop Hill from Burleigh Sands | Flickr - Photo Sharing!

The basics are:
Exposure 0.004 sec (1/250)
Aperture f/8.0
Focal Length 77.5 mm
ISO Speed 100


There wasn't much wind. The gliding club is the other side of the Loch and it runs a weather station, and it was showing 5 knots tops during the time I was there which is really pretty gentle. Given there are no leaves on the bushes and they are all stiff old growth at present I would expect them to be static - I didn't notice the bush near where I was shooting from moving. In June when there are leaves and new growth then yes, even 5 knots will make them wave around.

Are the rocks OK? Good question, not as easy to answer as one might expect!

The JPG from the camera is 6MB, I can upload it to Flickr as I have a Pro account, not sure you would want to download the whole thing. A selective crop or two might be more useful.
If you think a crop will help, put it up! But most of us have fast internet these days, so it would sure be easy to look at the full size file if you want to upload it.
12-31-2010, 01:01 PM   #13
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If you do a 1:1 crop of that particular area of the image, we might be able to see something. I suggest a crop of the bush out to the right edge of the image. We could then do our pixel peeking and see if we can see anything. We probably don't need the whole image.
12-31-2010, 01:17 PM   #14
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f8? for landscape? Where was your focus point?
12-31-2010, 02:12 PM   #15
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Focal point was somewhere around the island - the big tree is fine and it's almost the same distance away as the bushes. The background is all fine - the trees on the left sharpened up nicely.

I'll do a crop, do you want it from the PEG or the JPG?
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