Road photo quality question

[Mergingtraffic]

So all of my sign pics I take with an iphone.  First it was an iphone4 and since October an iphone 6s.  Iphone 6s has great clarity.

I noticed on some sign pics taken with the iphone 6s, the edges are jagged.  Anybody know what causes this or how can it be prevented?  Was it caused by damage to the iphone camera?

an example:

the button copy border at the top on this pic.

[1995hoo]

I was going to suggest maybe you zoomed in too much, but that first picture doesn't look zoomed-in.

[Mergingtraffic]

I was going to suggest maybe you zoomed in too much, but that first picture doesn't look zoomed-in.

the original pic is wider...I screenshot it after for a closer view of the sign.

[usends]

Sometimes this happens when you view an image at a random size; I think it's "noise" created by a mismatch between the image pixels and the screen pixels.  How do the photos look when you view the original images at 100% size?

[Mergingtraffic]

Sometimes this happens when you view an image at a random size; I think it's "noise" created by a mismatch between the image pixels and the screen pixels.  How do the photos look when you view the original images at 100% size?

The raw original image looks better, although I see it a little.  When I zoom in to screenshot it and add photoshop touches to it, the jagged edges look worse.  I also played with my computer's screen res and the lower it is, the more jagged the edges work.  Maybe, the iPhone 6s res is higher?  They look 95% ok on my iPhone 6s screen.  I just want good sign pics lol

[dgolub]

Sometimes this happens when you view an image at a random size; I think it's "noise" created by a mismatch between the image pixels and the screen pixels.  How do the photos look when you view the original images at 100% size?

That's right.  It's called aliasing and happen when you resize an image to a new resolution that isn't a whole number factor of the original resolution.  You won't get this at zooms like 50% or 25% but will at 40% or 60%, for example.  There are also more sophisticated algorithms for resizing an image that let you avoid aliasing at any resolution.  You can get them in a program like Adobe Photoshop.

[vtk]

Taking a screen shot of a picture on your phone, as a means of editing, is guaranteed to reduce the quality in one way or another. If you're going to edit the thing in Photoshop or a similar program on your computer, don't do any editing on the phone first. To "zoom in" on an area of interest in the picture, just use the crop tool, or take the picture with a zoom lens in the first place.

[Mergingtraffic]

Actually I just checked my raw original photos which I have on my computer, (I cut and pasted by right clicking the files from my phone to my computer) and noticed there's some aliasing on the untouched originals.
Could it be I got a "lemon" iPhone?

Obv if I screenshot it or if I sharpen them it looks worse. Thoughts? Thanks for the replies.

Original photo below:
JFX Baltimore, MD

[shadyjay]

Another iphone photo question:

I got an Android a few months ago, but continue to use my IPhone 4S for road photos, as its much easier to handle and take shots while concentrating on the road (yes I know - don't even say it).  Some of my shots I got last year make the signs look transparent.  Here's an example:

91SB-Exit12-11 by Jay Hogan, on Flickr

What would cause this?  Some sort of weird reflection?  The clouds/sun? 

[JREwing78]

I've seen that with morning condensation on signs - the parts of the sign resting against a brace or post heat and cool more slowly. The condensation appears on the other parts of the sign, but not the parts in contact with the post or brace.

[vtk]

Actually I just checked my raw original photos which I have on my computer, (I cut and pasted by right clicking the files from my phone to my computer) and noticed there's some aliasing on the untouched originals.
Could it be I got a "lemon" iPhone?

Obv if I screenshot it or if I sharpen them it looks worse. Thoughts? Thanks for the replies.

Original photo below:
JFX Baltimore, MD

How do I access the original image file on Flickr again?  The best I could come up with was an image that's about 1536×2048, which may or may not be your camera's native resolution.  If it is, then that's all the detail you're ever going to get with that camera unless you can use an optical zoom lens.  Having a camera with optical zoom capability is very handy for roadgeeky photos.  On the other hand, if your camera actually takes pictures with greater resolution than that, I can't offer much help without having access to the actual original files.

Another iphone photo question:

I got an Android a few months ago, but continue to use my IPhone 4S for road photos, as its much easier to handle and take shots while concentrating on the road (yes I know - don't even say it).  Some of my shots I got last year make the signs look transparent.  Here's an example:

91SB-Exit12-11 by Jay Hogan, on Flickr

What would cause this?  Some sort of weird reflection?  The clouds/sun? 

That's a kind of horizontal blurring effect, where light from the bright sky to the left and right of the signs bleeds into the sign faces, except where the thick gantry members are.  You'll notice, if you tilt the camera so the gantry isn't exactly horizontal, the light bleeds more evenly and it won't look like the gantry can be seen "through" the signs.  Anyway, this is caused by the a scratched or dirty lens, with grooves in a vertical orientation.  Clean the lens, and be sure not to rub back-and-forth in the same direction all the time.  If the lens is just dirty, this should clear up your pictures.  On the other hand, if the lens is scratched, perhaps from rubbing too hard while trying to clean it, there's really not much you can do about it.

[Mergingtraffic]

Actually I just checked my raw original photos which I have on my computer, (I cut and pasted by right clicking the files from my phone to my computer) and noticed there's some aliasing on the untouched originals.
Could it be I got a "lemon" iPhone?

Obv if I screenshot it or if I sharpen them it looks worse. Thoughts? Thanks for the replies.

Original photo below:
JFX Baltimore, MD

How do I access the original image file on Flickr again?  The best I could come up with was an image that's about 1536×2048, which may or may not be your camera's native resolution.  If it is, then that's all the detail you're ever going to get with that camera unless you can use an optical zoom lens.  Having a camera with optical zoom capability is very handy for roadgeeky photos.  On the other hand, if your camera actually takes pictures with greater resolution than that, I can't offer much help without having access to the actual original files.

As I right click on the pic on my drive it says "Dimensions 4032x3024.  Width 4032 pixels. Height 3024 pixels.  Horizontal & vertical resolution both 72 dpi.  Bit Depth 24.

[formulanone]

Sometimes this happens when you view an image at a random size; I think it's "noise" created by a mismatch between the image pixels and the screen pixels.  How do the photos look when you view the original images at 100% size?

That's right.  It's called aliasing and happen when you resize an image to a new resolution that isn't a whole number factor of the original resolution.  You won't get this at zooms like 50% or 25% but will at 40% or 60%, for example.  There are also more sophisticated algorithms for resizing an image that let you avoid aliasing at any resolution.  You can get them in a program like Adobe Photoshop.

Taking a screen shot of a picture on your phone, as a means of editing, is guaranteed to reduce the quality in one way or another. If you're going to edit the thing in Photoshop or a similar program on your computer, don't do any editing on the phone first. To "zoom in" on an area of interest in the picture, just use the crop tool, or take the picture with a zoom lens in the first place.

^ Pretty much all of this.

I also have an iPhone 6, and if the camera is not held very steady, the image will "skew" slightly, distorting the captured image into a parallelogram or rhombus shape. It doesn't happen often, but in the environment of a car or a low-light situation, it can happen. Another thing you can do is try to reduce sharpness at the time of the photo and avoid digital zoom, which amplifies edges to make up for more-blurry subjects.

When photographing sign edges, you have to consider the background, sign edge, the border, then a gap, and finally the text or logo...more so for button copy. The image sensor tries to sandwich that all together, but if it's not level-perfect straight, the image sensor will extrapolate the colors with some bit of guesswork, called "aliasing". The varying contrast between all those concentric layers is sometimes mis-interpreted, and it's exaggerated when the sign has a tilt to it.

Your default image width on an iPhone 6 is 4032 pixels; when you want a 800 pixel-wide image, that means dividing up the pixels by 5 and you're still left over with a tiny fraction. The colors of the pixels have to be re-sampled and merged together, and the software makes a pretty good guess at what that next color should be, although it's not always perfect. This increases the contrast a little bit in return...leading to the appearance of jagged edges.

This even happens with nice DSLRs, so it's not just cameraphones. Sometimes I find I have to change or crop the dimensions to something like 3600 pixels and then add a blur and then sharpen (or vice-versa) to get rid of jagged edges that appear where there is great contrast. It can get worse when you shrink the image down, and sometimes Flickr (as well as other hosting sites) creates its own algorithm to size the images as they'd please, or into pre-defined sizes.