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09-08-2012, 02:19 AM   #16
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QuoteOriginally posted by Fastback67 Quote
Had enough time today for one more quicky... Hope you like it!
Not so sure, Fastback. The lens flare effect is a bit harsh and not really in the right place relative to the shadows. That confuses viewers.
On the plus side, the church looks really nice.

09-08-2012, 02:28 AM   #17
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Thank you kindly, Fastback and Anton!
09-08-2012, 05:32 AM   #18
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QuoteOriginally posted by Anton Magus Quote
Not so sure, Fastback. The lens flare effect is a bit harsh and not really in the right place relative to the shadows.
Anton

The light was meant to be interpreted as a Beacon, as it was in my first image. It was a last minute attempt before traveling, so my apologies, I should have taken a few extra moments and done it right. Next time I'll put an image of the Holy Grail there with the light behind it so there is no confusion. Oh Wicked, Bad, Naughty Zoot!

Traveling now (with camera), so I'll see you all in about a week.
Till then, have fun everyone!
Mike

Last edited by Fastback67; 09-08-2012 at 07:43 AM.
09-08-2012, 07:52 AM   #19
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QuoteOriginally posted by Fastback67 Quote
The light was meant to be interpreted as a Beacon, as it was in my first image. It was a last minute attempt before traveling, so my apologies, I should have taken a few extra moments and done it right. Next time I'll put an image of the Holy Grail there with the light behind it so there is no confusion. Oh Wicked, Bad, Naughty Zoot!

Traveling now (with camera), so I'll see you all in about a week.
Till then, have fun everyone!
Mike
Apologies are complete unnecessary. I am enjoying the entries and the thinking behind them. Its all fun!
Enjoy your travels and return safely in due course.
Tony

09-13-2012, 10:25 PM   #20
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Using gimp...

I played a bit with the small image and I am attaching my result. I used gimp:

1. Rotated the image to straighten it
2. Used Perspective tool to distort image and correct perspective (pulled apart the top corners and brought closer the lower ones)
3. Applied a slight S curve to increase contrast
4. Decomposed HSV
5. Sharpened V layer
6. Recomposed back

That's it. I did steps 3-6 just to try and make it a bit better. This is the first time I am using the perspective tool too.

Now the self criticism:

The original image was tilted and the perspective distortion was quite strong. Correcting the tilting made me lose some corners. I also lost sharpness in the upper part - I could probably get a nicer looking sample by using the full-size image, but I think this attachment gives a better idea of how much I had to pull apart the top of the image to correct the distortion. A better result can be obtained by someone using more finesse with the perspective tool.
Attached Images
 
09-14-2012, 12:50 AM   #21
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Thanks for your entry, Laurentiu. Gimp is a very effective but often overlooked PP tool and it has
certainly worked to correct the perspective distortion in this image. Your entry also shows clearly
how correcting perspective distortion by widening the top part of the image also narrows the bottom part.

There are lessons here for all of us compact camera users to bear in mind.
  1. Photos of tall buildings taken from ground level and close up with a compact camera with the lens zoomed to wide angle will result in perspective distortion.

  2. To correct this distortion in post processing you will lose a chunk of the image from each side at the bottom, plus some of the top and bottom of the image, so allow a wide border of extraneous image around the prime subject that will be lost and cropped off when framing the shot AFTER you have corrected the distortion.

  3. As always, experiment with your own camera to learn how much extra space to allow. You may find that you need a starting image nearly twice the width and height of the primary subject.

Last edited by Anton Magus; 09-14-2012 at 01:26 AM.
09-14-2012, 10:44 AM   #22
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BTW, the issue is not with using a P&S. An SLR would have produced the same problem. There may be more barrel distortion in a P&S lens, but the main problem here is perspective distortion and that only depends on the distance from subject.
09-15-2012, 02:15 PM   #23
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Pretty much just a straight perspective correction without the bells and whistles using photoshop.


Last edited by wildman; 09-17-2012 at 09:31 PM.
09-16-2012, 07:30 AM   #24
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QuoteOriginally posted by wildman Quote
Pretty much just a straight perspective correction without the bells and whistles using photoshop
Thanks for your entry, Wildman. This is a tough image to fix because of the additional tower on the top right with the weather vane on top of that. Correcting the perspective of the main church seems to make the tower bulge outward - which it doesn't. Fastback, Bart and Laurentiu have all come very close to getting it perfect. I really like the rest of what you have done for the image - its much sharper and the contrast is great.
09-16-2012, 09:03 AM   #25
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QuoteOriginally posted by Anton Magus Quote
Thanks for your entry, Wildman
Yea - for me I wouldn't push it much further - too many other trade offs.

Maybe a tad better...

Last edited by wildman; 10-10-2012 at 06:05 AM.
09-17-2012, 05:03 AM   #26
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Hey there, I just got back!

I see a lot of folks posting that they have been using the Perspective tool to make corrections here, so I just thought I'd throw in my 2 cents. Myself, I used the Image/Transform/Distort tool in Elements to make the necessary corrections in the 3 images that I posted earlier, due to the severity of the required corrections. Not all in one go to be sure... a major correction here, a minor correction there, maybe a little tweak here & there.

Mike

Last edited by Fastback67; 09-17-2012 at 04:42 PM.
09-30-2012, 01:45 PM   #27
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Contest #3 Winner

Hi to all the people who entered (and followed) the Compact Camera Post Processing Contest #3.

This was a tough competition because correcting perspective distortion introduces all sorts of problems. First, most software narrows the bottom of the image rather than widening the top, but it also shrinks the top of the image downward. If you have enough free space around the primary subject this is not really a problem, but if you don't then bit get cut off.

The contest was mainly all about getting the church straight and vertical, so that is how I have judged the entries, although I must say that many entries improved the sky dramatically and some made a vast improvement to the sharpness and detail of the overall image.
The biggest problem with this particular image is that the church has a secondary tower sticking out on the right hand side. Just correcting the perspective normally to get the main building looking straight causes this smaller and taller tower to bulge out un-naturally. In addition this church has a flag pole and weather vane on top of the towers, both of which tended to get cut off when the perspective was corrected...
To judge more easily I have superimposed some lines onto the entries so we can really see who got the smaller right hand tower truly vertical.

Here are the results I know you have all been waiting for.
Ari (post #2) bravely went first and certainly gave the overall image a very strong "mood" by introducing a sombre cloudy sky as well as darkening the trees. Unfortunately the weather vane and flag pole got removed in the processing. As far as correcting the perspective, it was pretty good up to the clock level, but then bulged above.



Next up to bat was samtr87 (post #6) with a nice sepia toned effort. He got the left hand side of the church almost perfect but the dreaded "tower bulge" came into play with the right hand side. In addition the flag pole got lost in the processing.



Fastback (Post #10) got the perspective correction almost perfect, concentrating on the top of the tower and accepting a small tapering at the bottom. This was the first entry which met the main objective of properly correcting the pespective distortion and in addition I liked the magic he worked with the sky which not only seemed appropriate for a church, but also pulled the viewers eye to the top of the tower. But very sadly this magic was at the cost of the loss of the flag pole.



Next came Bart (Post #13) with a crisp B&W entry. Bart must have spotted the pitfall of the right hand side tower and seen that Fastback had corrected it. He also concentrated on getting the top of the building, above the clock level, absolutely straight, and succeeded. Without the lines I superimposed this building looks absolutely right to the eye. In addition neither the weather vane nor the flag pole were lost. Consequently Bart is the winner. Well done and congratulations, Bart.



Laurentiu Christofor (Post #20) then submitted an entry backed up with some very valid comments and observations. This entry was the most precise in terms of its correction of the distortion with both sides of the church being perfectly straight. Laurentiu left the image uncropped in order to graphically demonstrate the amount of post processing distortion needed to correct the image. While there was no penalty for this, I did have to deduct some points for cutting off the tops of the flag pole and weather vane.



Wildman (Post #25) deserves a special mention. When I first looked at the image it looked really "wrong". Visually it seems to bulge at the top and somehow it isn't quite right. However, when I superimposed the red lines I was amazed to find that they show the building to be almost perfectly straight. And it has the full flag pole and weather vane.


So why does the image look "wrong" and so different to the one from Laurentiu Christofor? Both images are virtually the same size and identically straight/vertical. As an experiment I loaded both images into photoshop and copied one image into a new layer created above the other image. I then made this new layer semi transparent so I could see Wildman's image with Laurentiu's image superimposed. Surprise! For some reason, while both images are vertical relative to the lines I superimposed, the buttresses in Wildman's image are distorted inward at the bottom.

Laurentiu used Gimp to correct the perspective by widening the top and narrowing the bottom. Wildman used Photoshop. It seems PS has narrowed the bottom much more and widened the top much less, so while they both seem to correct the perspective distortion correctly in terms of measuring the edges relative to superimposed true vertical lines, PS has distorted the internal structure in a way which is visually disturbing.

Perhaps there is a trick to learn out of this. When you correct perspective, strive for what looks good visually, rather than for upright edges that are perfectly vertical. You really just want to get rid of the weird looking "leaning" building effect. A second trick is to add more canvas to the image at the top and simply fill it with the sky color selected with the eyedropper tool. This means that when the top shrinks downward, you don't cut off the top of the building or a flag pole.

So, the winner is Bart and second place is, in all fairness, jointly shared between Laurentiu Christofor and Fastback. Both their entries were right on the button except for cutting off the flag pole. To Ari, Samtr87 and Wildman, sincere thanks for your entries which made the contest all the more interesting. The objective is to have some fun while learning rather than just winning. Hope to see more of your work in future contests. Thanks to you all and I look forward to whatever new challenge Bart sets for us.
09-30-2012, 02:20 PM   #28
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Congratulations Bart!!! Great Job!

Good work from everyone, really!

I realize many folks put perfection aside and went for more of an artistic interpretation of the image, and as long as everyone had fun doing it, that's all that matters!

Mike
10-02-2012, 07:48 AM   #29
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QuoteOriginally posted by Laurentiu Cristofor Quote
BTW, the issue is not with using a P&S. An SLR would have produced the same problem. There may be more barrel distortion in a P&S lens, but the main problem here is perspective distortion and that only depends on the distance from subject.
Or using shift.

This is what view cameras are for
10-02-2012, 09:25 AM   #30
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Wow. That is unexpected.
Thanks, Anton! and Mike.
Now to come up with a new challenge.
I'll have a look
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