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Old Jan 4, 2010, 7:45 AM   #11
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But, again, use the center focus point and see what you get before jumping to any conclusions (and check it using the focus test chart I linked to,, or use a controlled conditions test of some type like books or CD cases staggered at different distances).
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Old Jan 4, 2010, 3:03 PM   #12
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JimC, thanks again for all your efforts to help me with this, I REALLY appreciate it! The camera delivers great results when it works well, and I am really hoping to get the bestevery time.

I made a mistake with the wide angle lens, that one is a Sigma 10mm-20mm, as described here:
http://www.jessops.com/online.store/...5114/show.html

The images - I was trying to work out why the file size showing was different from what I uploaded! (I was able to check the EXIF was intact in the file I sent up). Sorry about that too - I have done a couple of smaller versions, which should be attached to this message.

They may be a bit small to show the soft focus well, it is not an extreme effect.

Is there something specific I should look for in EXIF info? perhaps a field "Did he give it time to focus?"

I'm putting together a plan at the moment. This lunch time I spoke to the shop where I bought it, (some time ago now), and they said they could get the AF checked out for me. This seems a good idea if only to put my mind at rest!

But before doing that, for the next week I intend to do some careful checking of the manuals to make sure I am not doing anything silly, and taking lots of test shots, to see if I can reproduce the issues, (or maybe get rid of them?!?!). I think it best to do this with my standard lens, rather than the extreme wide angle... (I have seen the phonomenon

I have already spotted a setting which should prevent the phot being taken if the camera thinks it's not sharp - it will be interesting to see if that does anything.

Thanks again for your help, it really is a lifesaver!
(Well, perhaps a marriage saver if I end up buying another camera)

Nick.
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Old Jan 4, 2010, 4:29 PM   #13
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I'll take a closer look at them as soon as I can take some time. Right this minute, I'm using an older PC, since it looks like I've got a motherboard failure on my primary PC (won't boot; never gets to post). Swapped PSU, swapped memory, removed unneeded cards, same problem. Grrrrr. I hate it when that happens. :-)

So, I don't have all of my usual software installed to take a look at proprietary maker notes information for anything that may be obviously wrong, although Elements may have stripped it out). I'll see what I can find when I have a bit more time this evening.

But, on the surface, it looks like you may have a focus issue *if* you're using the center focus point (and that's the first thing I'd change to see if that solves your issues). Focus planes are not very flat with an ultra wide lens. ;-)

If not, the best thing to do is check it using something like the chart I linked to and see if you've got a front focus or back focus issue. Then, repeat the test with a different lens to see if it's a lens or camera body issue. Chances are, it's a lens issue if you have a front or back focus problem (and Sigma can recalibrate for you).
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Old Jan 4, 2010, 5:08 PM   #14
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Just a note on shooting panos: you are best using manual focus since autofocus might have one frame focused on something close while the next focuses on something far away.

That is unlikely to fix the basic problem JimC is doing so well figuring out. I would add that you might look in the detailed EXIF data to see if it estimates subject distance (or some other measure of distance). Again, unlikely to address your basic problem, but kinda neat to look at when figuring out focus issues.
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Old Jan 4, 2010, 6:09 PM   #15
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I didn't find any Makernotes in the EXIF data for these, which doesn't make sense unless Photoshop is stripping them out.
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Old Jan 4, 2010, 9:05 PM   #16
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A few things from an A200 user. I have shoot over 18,000 images with it. It is now my backup camera.

1.) When you shooting panorama shots I find the best way to do these is to use the exposure lock button and not let AF take over frame to frame. At least that is how I get the best results on my A200 and let Photoshop Elements 7.0 sitch them together. I get worst results with manual focus and letting AF do it thing frame to frame. My panoramas are mainly of a high school being built and are 4 to 6 frames joined together......

2.) The AF issues you are having. The only time I really had any issues with my camera was using the original kit lens 18 - 70mm which I stopped using about 4 weeks after I got the camera. Did the same thing you speak of.

dave
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Old Jan 4, 2010, 9:07 PM   #17
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I'm not seeing any maker notes in those either (I just looked using more than one software package)

So, Photoshop Elements probably stripped it out. I typically use either Irfanview (in Windows), or digiKam (under Linux) for resizing to prevent that kind of thing.

Anyway, some Exif viewers will tell you the AF area mode and focus point used. For example, PhotoME will give you that info for the A200 (at least the latest beta version of that software, which I just installed in Wine under Linux on this desktop to check those files).

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Old Jan 5, 2010, 3:37 AM   #18
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Quote:
Originally Posted by JimC View Post
I'll take a closer look at them as soon as I can take some time. Right this minute, I'm using an older PC, since it looks like I've got a motherboard failure on my primary PC (won't boot; never gets to post). Swapped PSU, swapped memory, removed unneeded cards, same problem. Grrrrr. I hate it when that happens. :-)

So, I don't have all of my usual software installed to take a look at proprietary maker notes information for anything that may be obviously wrong, although Elements may have stripped it out). I'll see what I can find when I have a bit more time this evening.

But, on the surface, it looks like you may have a focus issue *if* you're using the center focus point (and that's the first thing I'd change to see if that solves your issues). Focus planes are not very flat with an ultra wide lens. ;-)

If not, the best thing to do is check it using something like the chart I linked to and see if you've got a front focus or back focus issue. Then, repeat the test with a different lens to see if it's a lens or camera body issue. Chances are, it's a lens issue if you have a front or back focus problem (and Sigma can recalibrate for you).
Thanks Jim, if it takes weeks to resolve this, I'll still be happy! Been there done that with the PC issues, always a pain...

In the mean time I'll carry on practicing and experimenting.#
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Old Jan 5, 2010, 3:47 AM   #19
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Quote:
Originally Posted by BillDrew View Post
Just a note on shooting panos: you are best using manual focus since autofocus might have one frame focused on something close while the next focuses on something far away.

That is unlikely to fix the basic problem JimC is doing so well figuring out. I would add that you might look in the detailed EXIF data to see if it estimates subject distance (or some other measure of distance). Again, unlikely to address your basic problem, but kinda neat to look at when figuring out focus issues.
Thanks Bill.

I think I'll look fora prog that can pull out all the exif infointo a text file. PSE is a bit of a pain to move between all the options.

I'm used to using auto everything for my panos, worked well with the old camera. (Apart from getting broad banding in clear blue skies). I kind of figure a smooth blend between well exposed and focused images has it's own strengths, though I know that lock everything is the more popular technique.

TCav, I'll try a diofferent program - I coul see that some stuff at least was still there arfter PSE shrunk, I checked it before uploading.

Photo-5, thanks for the input. My prefered stitching tool is PT Gui, which I have been using for some years. In my experience it does a great job, even with no manual tweaking. What were the issues you were getting with the kit lens, and what did you choose to replace it? (I never understood why manufacturers sometimes supply poor lenses with their cameras - itcan only give a bad impression...)

Nick
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Old Jan 5, 2010, 4:52 AM   #20
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Quote:
Originally Posted by starbase1 View Post
I think I'll look fora prog that can pull out all the exif infointo a text file. PSE is a bit of a pain to move between all the options.
Maker notes are proprietary to a manufacturer. IOW, they don't publish the information about the tags they're using. As a result, developers need to reverse engineer them to try and interpret the data (using techniques like changing a specific setting to see what changes in the maker notes). Fun. lol

PhotoME can give you a lot of information about your camera settings (outside of the information you see in the main EXIF section). You may also want to look at ExifTool by Phil Harvey:

http://www.sno.phy.queensu.ca/~phil/exiftool/

There is also a front end called ExifTool GUI designed to work with it (although ExifTool GUI dosn't support all of it's features).

http://freeweb.siol.net/hrastni3/fot...xiftoolgui.htm

But, the first thing I'd do is check your AF for front focus or back focus with that lens. Ditto for the kit lens (if it's off with the kit lens, the camera body may be out of calibration). There are actually some hex screws you can use to tweak the AF sensor position. But, your best bet is to let Sony (or Precision) calibrate it for you if you do have a body problem.

Chances are, the Sigma lens is the issue if you're using the Center Focus point and are careful what you're focusing on. They've got a reputation for QC related problems impacting Autofocus and sharpness, and lenses sometimes need a trip back to the manufacturer for rechipping and/or recalibration.

If you read through some of the user reviews, you'll note that some users had to try multiple copies to get a good one. That's not uncommon with Sigma's 10-20mm. I've seen the same thing with it on other camera mounts.

Note the comments from D-Schap from March 12, 2009, where he discusses that it was soft out of the box and returned it to Sigma and it's much sharper now.

http://www.dyxum.com/reviews/lenses/...asp?IDLens=225

Quote:
There have been at least five other users of this lens that have had the same issue with their NEW purchase. I suggest IF there is any question of this lens' focal performance, return it to SIGMA for adjustment, do not swap it with the retailer, because the chances are ... you'll get back the very same problem. The Manufacturer's focal alignment Quality Assurance is definitely in question.
Most users seem to think it's much better by the time you get to f/8 with it. IOW, don't use it with the aperture wide open, stop it down to f/8 or so instead).

But, if you find it's still soft (and/or AF accuracy is off), I'd probably let Sigma recalibrate it.

http://www.sigmaphoto.com/sigmaonlinemall/service.asp
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