goldenyears Loc: Lake Osewgo

I took a photo which has a lot of straight lines. But I neglected to pay enough attention to leveling the image. So the lines have a "stair-step" appearance which I think is Do I have any choice other than to acquire yet another photo editor?

Rongnongno Loc: FL

Yes, go back and shoot again, if you can.

Architect1776 Loc: In my mind

What will change if you shoot it again with the same equipment?

larryepage Loc: North Texas area

I presume he is going to be more careful to level the image and avoid "diagonal" lines. If so, that should eliminant the problem.

Architect1776 Loc: In my mind

What if the image IS level and the lines are not level for numerous reasons including perspective receding lines.

larryepage Loc: North Texas area

Then I guess reshooting might not be the solution he is hoping for.

Rongnongno Loc: FL

In this case, the alignment correction needs to be done before any other edit.

Cany143 Loc: SE Utah

Straight lines are straight lines whether they're horizontal, vertical or anywhere in between. By --as you wrote--having "neglected to pay enough attention to 'leveling the image" we're (I'm) left to assume that either the horizon line is off-kilter or whatever other 'straight lines' your image contains are tilted some number of degrees left or right from where you want them to be, and ultimately that's what you want to 'correct' by making 'level'. Is that accurate, or have I missed something? If so, virtually any software I'm aware of should have several ways of 'tilting', 'leveling', 'rotating', 'skewing', etc., the image incrementally to get it to where you feel it's 'right', or 'level' or whatever, and odds are whatever software you may have has just such a tool or feature, but you may not have come across it quite yet. Is this also an accurate assumption?

NONE of the above, however, has ANYTHING to do with any 'stair-stepped' appearance your 'straight lines' may have acquired. That is, as alluded to in your title, one possible result of aliasing, and in particular, it can be encountered in extremely low resolution, highly compressed 8 bit or less .jpg and/or .gif images, and when seen is often called "having the jaggies". Are there ways to 'correct' --or soften-- the 'jaggies'? Sure, but they're never ideal, and usually result in an unwanted decrease in the perceived sharpness of the image, usually to the point that the image becomes mushy and --unless one has intended some sort of abstraction-- little more than a candidate for the <delete> key.

Maybe you could post an untouched (other than downsizing such that it's postable) example of the image/images that is/are giving you problem? And mention what software you have available?

therwol Loc: USA

Did you resize the picture? I learned early on (This picture was taken in 2005 with a 5 megapixel camera) that if you resize a picture, sometimes straight lines will acquire a "stair-step" appearance. The first picture is the original. The second is the picture resized to 35% of the original. I cannot store the original of the resized photo, so in order to see what I'm talking about clearly, I magnified a portion of the image and made a screenshot. That's the third image. The original doesn't look anything like this. Download it and compare.

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bikinkawboy Loc: north central Missouri

Interesting results. Single strand am ooth hi-tensile wire takes on the appearance of two strand twisted wire.

Keep in mind that more often than not, hi-tensile wire is electrified, which that fence wasn’t. If you see white or yellow plastic or white porcelain insulators between the post and wire, DON’T touch it. If you want to see if a wire is electrified, take a blade of green grass 3-4 inches long. Holding it between you fingertip and thumb, lay the end of the blade of grass on the wire. Slowly reduce the distance between the wire and your fingers. Depending upon how powerful the energizer is, you will gradually start feeling the tingling pulses if the wire is hot. Do it slowly or you’ll get zapped!

bikinkawboy Loc: north central Missouri

That’s supposed to be “smooth”, not am pith. Damn autocorrect!

bikinkawboy Loc: north central Missouri

It changed again!!!

JimH123 Loc: Morgan Hill, CA

The opposite resize works in the opposite direction and smooths out the jaggies.

Also, the angle of the wire, and also thickness, play a role in seeing Maggie's. Running perfectly horizontal, or perfectly vertical will have no jaggies.

If not perfectly horizontal, or vertical, then you can have situations where for every two horizontal pixels, you move 1 pixel vertically, or other such patterns.

Now let's resize by +2x. Now you have 4 times the pixels, with each pixel being 1/4 the size, and the stair stepping becomes less visible. Thus with the 5M pixel original, it becomes 20M pixels, and no visible jaggies.

R.G. Loc: Scotland

More information is needed for a helpful answer. Assuming that it is simply a levelling problem, one of the best methods is to look for a known and reliable vertical that's on or close to the vertical centreline of the image and use that as your reference for straightening. Even if there is considerable perspective distortion in the form of vertical convergence (keystoning), the verticals on or close to the vertical centreline are still good references.

kymarto Loc: Portland OR and Milan Italy

What are you using to level the image? I rotate many images to correct the horizon and have never seen this.