White fringe

[mikew_RIP]

The Tammy takes a 95mm, that's not an uncommon filter size... You would be able to find a cheap one (just for testing purposes) for less than $50 USD. A proper one would set you back $300 USD or close to it, that's true; but you knew what you were getting into when you bought the Tamzooka...



Clearly, from the photos, the affected pixels are blown out; so I'm not surprised you can't recover any detail there. I don't think this is a natural phenomena, and by "natural" I mean I don't think this is being caused by light as it is entering the lens. I think this is contrast/edge detection aberration (I'm coining that phrase right now); which means the camera's processing is creating the problem under certain circumstances and, further I'll wager, once this aberration is there, it's going to be next to impossible to remove "globally", like you can with CA.

Methinks if you want to fix it CORRECTLY, you're going to have to learn how to avoid it, which may be impossible on a practical level (unless a CPL knocks it out) or... you're going to have to Zoom in to pixel-level using Photoshop or Lightroom or whatever you use, dial down your Healing Brush or Clone Stamp tool and do "corrective surgery" at that level. It's tedious but I've been known to do it because sometimes that's the only thing that works.
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Think your talking about what i had a crude go at down its chest.

 

[Horoscope Fish]

Think your talking about what i had a crude go at down its chest.

I did some quick and dirty Clone Stamping to the right side as well and though it needs more more attention I think it's a definite improvement:
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...Original...................................................................................................................Clone Stamped
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[J-see]

I did some quick and dirty Clone Stamping to the right side as well and though it needs more more attention I think it's a definite improvement:
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That looks indeed a lot better but considering the amount of shots that suffer it, I'm in for some work. I'm going to test some blending and see if I can get that going.

 

[J-see]

It might have something to do with tone-mapping. I encountered a rather similar problem that is apparently an issue in HDR. High contrast areas there can also trigger halos.

I'll quote something out of the Wiki on the subject:

However, HDR tone mapping, usually using local operators, has become increasingly popular amongst digital photographers as a post-processing technique, where several exposures at different shutter speeds are combined to produce an HDR image and a tone mapping operator is then applied to the result. There are now many examples of locally tone mapped digital images, inaccurately known as "HDR photographs", on the internet, and these are of varying quality. This popularity is partly driven by the distinctive appearance of locally tone mapped images, which many people find attractive, and partly by a desire to capture high-contrast scenes that are hard or impossible to photograph in a single exposure, and may not render attractively even when they can be captured. Although digital sensors actually capture a higher dynamic range than film, they completely lose detail in extreme highlights, clipping them to pure white, producing an unattractive result when compared with negative film, which tends to retain colour and some detail in highlights.

Tone mapping - Wikipedia, the free encyclopedia

Since the fringe is there on load, I suspect it is caused by the tone-mapping done in cam or in editor when it had to press the DR of the scene into the DR of the cam. If it is a tone-mapping byproduct, using curves to compress a part of the range might fix it.

 

[J-see]

I found the easiest method, although easy is relative here.

I replace the colors; I pick a color in the fringe halo, set the range and then adjust the lightness. It takes a couple of times to get enough to make it disappear.
Then I use a copy of the original and brush in those parts affected in the rest of the image.

 

[J-see]

I discovered that playing with the highlights in PS and lowering or zeroing the area and tonal range (which is the Camera Raw plugin I assume) does miracles when it comes to this fringe. It doesn't always completely remove it but at worst it is just a thin outline which is more visible in a scaled version of the shot than the shot itself.

While battling the fringe, I also experimented with sharpening. In fact, with not sharpening. The last two or three days, >90% of my shots I didn't sharpen more than the 25 LR automatically applies. When I check my RAWs, a good shot has some sharpness even when unedited.

Here's two; one sharpening disabled, one with the standard 25 LR applies. It's a reasonable crop.




By limiting my sharpening, I also limit the fringe problem in these kind of shots.

 

[J-see]

I got the contrast fringe about solved.

It gets magnified by two things; sharpening and JPEG conversion.

I quit using sharpening techniques based upon unsharp mask which make it stand out too well and I save my JPEGs to the format they'll be displayed. For here it is 1024*768 and when saved and viewed at that scale, there's hardly ever a problem. In really bad contrast cases it can still show a bit but it's rare compared to before.

It only shows well in the images on the forum itself which are again scaled versions of the JPEG. This scaling triggers the fringe but once the shots are clicked and open in their normal format, all is fine.

All in all the solution is easy once you know what triggers the problem.

 

[Eyelight]

Just wandered across this thread for the first time.

Curious if you see the white fringe on subjects that are entirely front lit?

 

[J-see]

Just wandered across this thread for the first time.

Curious if you see the white fringe on subjects that are entirely front lit?

I'd have to go through my shots but I think most of them, at least the worst, are back-lit shots.

 

[J-see]

Here's one of today. It's not the sharpest but it's the only one I had left that is front lit to a degree. I cropped and doubled a part of the unprocessed RAW.



The part that isn't lit, and is shaded, shows the fringe.

 

[Eyelight]

I'd have to go through my shots but I think most of them, at least the worst, are back-lit shots.

I imagine if the subject is backlit, the fringe will be overexposed compared to the body on any edge except one that is absolutely smooth and not fuzzy (in a microscopic sense).

 

[J-see]

I imagine if the subject is backlit, the fringe will be overexposed compared to the body on any edge except one that is absolutely smooth and not fuzzy (in a microscopic sense).

The fringe is colorless indeed and is purely related to exposure which makes it annoyingly hard to remove. How this exactly happens I wouldn't know. I know photons that are out of sight for the cam can still hit the sensor and in that, trigger more exposure than we'd expect but if that's the reason for these fringes I would not know.

It shows in the RAW from start and this far the only good approach I discovered is to make sure I don't make it worse.

 

[Eyelight]

The fringe is colorless indeed and is purely related to exposure which makes it annoyingly hard to remove. How this exactly happens I wouldn't know. I know photons that are out of sight for the cam can still hit the sensor and in that, trigger more exposure than we'd expect but if that's the reason for these fringes I would not know.

It shows in the RAW from start and this far the only good approach I discovered is to make sure I don't make it worse.

It's a natural thing. Here's an extreme example. We think of a leaf as having a smooth edge, but it's rough enough to catch the light and not block it as much as the rest of the leaf. The result is the edge is overexposed. This is more pronounced because of the dark background.

 

[J-see]

It's a natural thing. Here's an extreme example. We think of a leaf as having a smooth edge, but it's rough enough to catch the light and not block it as much as the rest of the leaf. The result is the edge is overexposed. This is more pronounced because of the dark background.
View attachment 141951

I've been looking at auras and other phenomena to find an explanation for it but didn't find anything which did fit. This fits the problem completely and explains why about anyone using whatever lens suffers the problem. The only difference is the degree to which we suffer it which is a post issue.

Thanks for clearing up this mystery. Do you maybe know the name for this effect?

 

[Eyelight]

I've been looking at auras and other phenomena to find an explanation for it but didn't find anything which did fit. This fits the problem completely and explains why about anyone using whatever lens suffers the problem. The only difference is the degree to which we suffer it which is a post issue.

Thanks for clearing up this mystery. Do you maybe know the name for this effect?

I think most people would call it a halo effect if done creatively. Otherwise, I suppose it's just blown highlights.

 

[J-see]

I think most people would call it a halo effect if done creatively. Otherwise, I suppose it's just blown highlights.

I didn't mean what we call it but if there's a scientific name for the phenomena.

At least now I know there's nothing I can do to prevent it (besides not shooting backlit) and that even a CP filter will not help. And since I also know how to handle it in post, it's one problem less on the list.

Thanks again.

 

[mikew_RIP]

[MENTION=31330]J-see[/MENTION] If you get mixed notifications it because i posted this and then deleted it to move here.

Have you tried this,its shown working on B/W but i have used it on color on occasion,just had a very quick play with your picture,about 30 seconds.

https://www.youtube.com/watch?v=wcOZcwHdqz8

 

[J-see]

@J-see If you get mixed notifications it because i posted this and then deleted it to move here.

Have you tried this,its shown working on B/W but i have used it on color on occasion,just had a very quick play with your picture,about 30 seconds.

Thanks, I'll try it out.

Ian is a very enthusiastic guy isn't he?

 

[hark]

This video showed up in my Facebook news feed yesterday. It identifies a way to sharpen while trying to avoid the fringe or halo effect that sometimes occurs from sharpening. Near the end of the video he edits a building using this method.

 

[mikew_RIP]

This video showed up in my Facebook news feed yesterday. It identifies a way to sharpen while trying to avoid the fringe or halo effect that sometimes occurs from sharpening. Near the end of the video he edits a building using this method.

Thanks,have bookmarked it to watch when i wake up