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Need Help - How Can I Fix This


D

DawgFather

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You can see the stripe and under the door how it looks choppy. How can I fix this? I have been trying to fix this but just can get it looking good, natural.

Feel free to give it a shot. If you know how I can fix this, I would like to learn how its done as well.

Car_0001_zps74f99376.jpg
 
For the bottom choppiness, I would take the brush or pencil, select the color (alt/opt click). Make sure the brush is set to hard and is the width of the largest reflection. On another layer, click the brush tool at the beginning of the line, then hold shift and click the brush again at the end of the line. Use a mask or eraser at the ends if it looks like it doesn't blend well.

For the stripe, it is going to require use of the pen tool, IMO. Make a path for the section to the right of the "CIVIC;" then make one for the other side. Be sure to stay inside the white stripe; you'll see why in the next couple steps. You can do both of these on the same path layer. Then make another layer above. Select the color of the blue, ctl/cmd click on the path and fill it with the blue color. Now go to layer effects and make a stroke that is the right width and color. If you are very careful about the pen tool path, your outside stripe of blue should remain intact.

If you are not familiar with the pen tool, here is a good chance to learn it. It does take some practice but it is a supremely useful tool.
 
ibclare said:
For the bottom choppiness, I would take the brush or pencil, select the color (alt/opt click). Make sure the brush is set to hard and is the width of the largest reflection. On another layer, click the brush tool at the beginning of the line, then hold shift and click the brush again at the end of the line. Use a mask or eraser at the ends if it looks like it doesn't blend well.

For the stripe, it is going to require use of the pen tool, IMO. Make a path for the section to the right of the "CIVIC;" then make one for the other side. Be sure to stay inside the white stripe; you'll see why in the next couple steps. You can do both of these on the same path layer. Then make another layer above. Select the color of the blue, ctl/cmd click on the path and fill it with the blue color. Now go to layer effects and make a stroke that is the right width and color. If you are very careful about the pen tool path, your outside stripe of blue should remain intact.

If you are not familiar with the pen tool, here is a good chance to learn it. It does take some practice but it is a supremely useful tool.
Click to expand...

Thank you so much ibclare for taking your time to help me on this. I only did a section on the door, it's the easy section. I did the CIVIC letters as well, it needs work. Or I need to work on it. :lol: I will need some practice but I will get it better.

Thanks again for your help. :thumbsup:

Car_0002_zps258100a5.jpg
 
You are experiencing what are called "stair-step aliasing artifacts". As you are finding out, they can require a lot of manual busy work to minimize them once they are formed.

If you want to read a bit more about them, start with these two articles:
http://www.answers.com/topic/aliasing and
http://www.answers.com/topic/antialiasing

This is just the tip of the iceberg -- this is a common problem and there have been thousands of technical articles written on this subject -- just Google {stair step aliasing artifact} and you will get ~600,000 hits.

By far, the best way to get rid of them is not to let them form in the first place.

For photographers, the usual reason they occur is that a high rez image is oversharpened, and then down rez'ed to lower pixel dimensions for emailing, posting to web, etc. The initial oversharpening is almost always done to try to maximize the sharpness of the final image, but this is almost always the root cause of these artifacts. Instead, only do very modest amounts of sharpening to the high rez version, then down rez it, and apply the majority of your sharpening after down-rez'ing. You will likely be astonished at the improvement in image quality.

HTH,

Tom M
 
At the risk of stating the obvious, in addition to the reason given in my previous post, stair-step artifacts can also occur if you attempt to up-rez (ie, increase the pixel dimensions) an image and then attempt to reduce the blurring by sharpening. I doubt this is what happened to this image, but thought I'd mention it for completeness.

T
 
Tom it is very possible this is exactly what has happened to this image. It was shot in 2011 with a COOLPIX L110 so he may have tried to manipulate the image and did not keep the original. And it was 8 bit, I changed it to 16 bit thinking it would be much easier to work with more colors to try and fix it. I still have the 8 bit image that was given to me if that would make it easier to fix it that way.
 
Hi Dawg - The bit depth has nothing to do with these types of artifacts. It's all about changing the pixel dimensions -- both the algorithm you use to do so (eg, bilinear, one of the bicubics, etc.) and sharpening applied.

However, why don't you post the most original version you have (in full rez - don't touch it), and we'll take a look at it.

Tom
 
Yes, I was aware of the res problem, but focused on the fix. Indeed it would be better to start with a better image and not have the problem. But not always possible I see. "Hopefully" the original is in better shape.
 
As far as I know the image in the first post is the only one he has. That is the only one I have to work with. I think what he did was he did some editing and then saved it. Replacing the original with his edited copy. He had been looking for the past 3 months for someone to help fix this for him. No one stepped up so I am giving it a shot for him.
 
Hi Dawg - Thanks for the info on the background of this image. I guess you are stuck trying to repair it. Clare's suggestions are really good and I'll also give some thought to repairing it. FWIW, I already tried a plugin I have called "Anti-Alias" by Power Retouche Pro. It usually works pretty well on edge artifacts that only span a couple of pixels, but it just couldn't handle such large scale stairstepping.

T
 
When the stair steps are occurring along parallel, nearly straight lines, motion blur is a quick way to reduce this artifact. In the image below, I first used Topaz deJPG to reduce all the horrible JPG artifacts in the image, then the patch tool to clear up some of reflections / dent in the door, and then motion blur (masked to include only the nearly horizontal parallel problematic lines/edges).

Cheers,

Tom M

Car_0001_zps74f99376-tjm02_fix_stairstepping-acr0-ps01a_motion_blur-patch-deNoise-crop-8bpc.gif
 
Looks quite good. Lot better than the original. Did you use Tom Mann's suggestion to overcome that problem or did you use some other method? It would be handy to know how you did it. Thanks!
 
Adding: When I zoomed on the image, I found a flaw at the edge of the door. The paint should have a gap there. Then this would become lot better IMO.

Sorry for the 2nd post in succession here. I am new, and do not still know how to edit a post... Thanks again.
 
santoshb said:
Looks quite good. Lot better than the original. Did you use Tom Mann's suggestion to overcome that problem or did you use some other method? It would be handy to know how you did it. Thanks!
Click to expand...

Sorry about that. I should have stated that in my other post. I need to learn proper forum etiquette as well. I'm not a big forum guy. I'm only on just one other forum. lol

Yes I did use Tom Mann's suggestion in post #12. It was a much easier process, for me anyway. I used the Polygonal Lasso Tool to make my selection of the stripes, below the door and the upper window frame.

Thank you Tom for posting what you found to work well, it was a big help. :thumbsup:
With a bit more practice, I think I can do better with your technique. So that I get better results in the future.
 
Glad to have helped. Unfortunately for me, a year or two ago, I needed to do the same sort of repair, so it was pretty fresh in my memory.

T
 
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