About three months ago, my Nikon D600 started producing images with a narrowly overexposed arc that swept across the image from top to bottom through the center of the frame.
Initially, I assumed it was a strong flare that came when I shot into the sun and would not be an issue in other situations and, in truth, this curved bright line was not noticeable when shooting indoors and barely noticeable on photos in which there was not a continuous block of color in the composition.
I continued using this camera for some of my event and press work, but when I took the camera and a 35mm lens with me on a beach vacation, I was disappointed to see that many photos, in fact, every photo with a large portion of bright, uniform color (especially blue sky and sand), displayed this same problem.
Upon my return from vacation, I tried the camera with various lenses and the same 35mm lens on different cameras. It became clear that the problem was in the camera. Knowing that, I put the camera on manual and tried shots of the sky at different aperture values and shutter speeds, but it always produced the same arc, the only difference being that at wider apertures, the arc was a bit soft at the edges and at f/11 and above (smaller apertures) the edge of the arc was more defined.
My main concern was that the sensor was damaged and the camera might be irreparable or too expensive to warrant a repair. It was very possible that I damaged the interior with rough use or salt water, but I did continue to use the camera when I was shooting interiors. Eventually I asked some B&H colleagues for their thoughts, and many offered opinions; one idea proffered held some possibility for an explanation—had I used canned air to clean my camera recently? This I had done but was careful to not spray the blast of air directly at the sensor. Of course, many reminded me that the D600 had encountered complaints upon its release, in late 2012, that dust and oil were accumulating on its sensor, and some felt that the release of the D610 just a year later was an admission that something might be wrong with the shutter unit of the D600. Could it be a problem with the shutter? But my camera had worked flawlessly for almost five years and the issue I was facing was not like what had been described in 2013.
Since the arc was in the exact same spot on the image frame and relatively consistent with varying f/stops, shutter speeds and on sequential images,
I was convinced the problem was with the sensor, and I considered just buying a new camera—after all, I had had this camera for almost five years and used the heck out of it. But the time came to consult a professional, so I took my camera to Photo Tech Repair Service, a trusted camera repair shop, just around the corner from B&H. They promised to get back to me within three days with their diagnosis and an estimate on the repair cost. The next day they called and emailed me. Before I go any further with this story, we would like to engage with some of you readers—let us know your expert (or not) opinion on what is wrong with my camera and I will follow up next week with what was ultimately diagnosed by the repair shop.
We’d love to get your thoughts in the Comments section, below, on what’s wrong with my camera, based on the above images.
For the epilog of What's Wrong with My Camera? Part 2, click here.
44 Comments
I see the arc through the photo but also noticed a lot of spots in some of the sky. What is causing that? Interresting article!
Damn! Do you get paid by the word! Get to the point, blah. blah blah!
Glad your camera is fixed.
Okay, so it's a month later. What was the cause of the problem?
My guess is that this is a shutter problem. Many of the vertical shutters I've seen have a mechanism that rotates in an arc (as opposed to a linearly moving part in a straight line). Maybe a pinhole or tear on the shutter blade, or on one of the pivot points between the rotating arm and shutter blade will let extra light hit the sensor.
Thank you very much for this feedback louis.
I know that my comment is unrelated to the problem discussed, but years ago I had problems with two models of Nikon cameras F3 and F100, then waited years for Nikon to come out with their Vibration reduction lenses, so after 30 of using Nikon.....I switched to Canon, problems solved!
Hah....good one frank. I dont think I need to go that length...yet!
Could there be a scratch in the black coating in the mirror box that is reflecting onto the sensor?
No, no scratch. Thanks for the comment Richard.
I need to KNOW!!!!! When is part 2 coming out?
Thanks Need to Know...I am writing it today....
Um, John....
The week has come, and gone, and I'm still hanging here twisting in the wind :-)
Matthew...the article is written, just needs to go through the editorial process, should be published next week. Thanks again for your interest....
Because the aperture of the lens has an effect on the arc, I think it is something between the lens and the sensor and it is something that is closer to the sensor than the back of the lens but not too close to the sensor. Because the effect is steady, it is inside the body of the camera. If it had been something in front of the mirror it would probably had been visible, so it is behind the mirror. Probably it is a reflection on something spherical on one side and in the middle of the height of a wall hidden by the mirror in its down position. This "something" is very shiny and it is its specular reflection that does the arc. Maybe I am wrong, but to me, it seems logical.
Thank you Richard
I had a Canon 1D mkII with a similar problem once. I turned out to be a hole in the shutter - the mech shutter had actually broken but luckily Canon replaced it for free because it had a really low shot count. Not sure if this is the same thing but the result appears to be the same.
Very interesting...thanks for the feedback Alan.
I had this exactly issue myself.. looked exactly the same.. turns out it was a hair on my sensor.. somehow it got in there and was resting on the sesnor itself.. don't rembmer how i got it off.. I think i used my finger and very very gently dabbed the hair to stick to my finger and pulled it out. hopefully whats wrong with your camera is something very similar and an easy fix.. have you actually looked at the sensor yet?
Robert....yes, I did check the sensor and while it was a bit dirty, there was no hair or any major flaw that would have caused the problem. Thanks so much for the feedback.
My I just ask a question of you. This looks to me like a reflection Problem. Do you ware glasses? Are they metal frame glasses?
I had a simular problem when I took pictures on bright sunny days. My glasses left a reflection in the lens. Thats why indoors worked and so did cloudy days and well shaded areas.
Thanks for the reply K -- interesting thought, but no I don't wear glasses. (I'm starting to feel guilty about this...and I dont like to be cagey, but by late next week we'll publish the updated piece, with the diagnosis and fix.)
I'm wondering if it's a faulty SD card interacting with the codec.
Thank you Michael for the feedback, but the SD card is fine.
Thank you everyone for your comments so far. We will leave this post up for another week before I add part II with the official diagnosis and with hopes to get a few more explanations, but in the meantime, I'll address a few of the questions below.
To Mr. Jasiak...yes the arc is still visible in shots taken out of focus and no, I never tested it on video, although I suppose I should have.
To Mr. Owens...yes I did use a lens hood and the arc was still there in the type of shots described in the article.
And finally, just to continue with the cat and mouse game (which I must admit I am enjoying), the sensor was (and is) absolutely fine. Sensor damage or somthing on the sensor was not the problem and the camera has been affordably repaired and is now working fine.
Thanks again for the feedback.
Ah, cruel fate! Left hanging there to twist in the wind for another whole week :-) :-) :-)
LOL. Thanks for the comment Matthew
I noticed that the arc is most obvious in darker images, with sharper edges. In brighter images, the edge is diffuse and the arc contrasts less with the rest of the image. Given these facts and the round shape of the defect, my guess is a light leak from through the viewfinder reflecting off the back side of the mounting ring.
Thanks for response Greg.
Or could it have something to do with the movement of the SLR mirror in conjunction with that of the shutter? Just a WAG... from another fool.
Why not? If a small glittery item on the mirror (it has to receive light) were oriented so as to reflect elsewhere onto the sensor, it might create a diffuse curved path of light across the sensor as the mirror moved through an arc. Welcome to the crew of those who have fallen into Mr. Harris' trap, by the way :-)
Thanks Charlie...from the explanation given to me, it seems like you are on to something. What is WAG, btw?
Oh...he's given us just enough rope to go hang ourselves :-) :-) That said, here I go likely to make a fool of myself by guessing the cause.
Mr. Harris has already done a lot of the investigative work and eliminated the lenses as a source of the problem and restricted the cause to the camera body.
OK. Notice the curvature of the streak. This means something with curvature is involved with it. Sensors are not curved (they'd better not be :-) so that is not so likely to be the source of the problem. Curves in the camera body are largely in the mounting for the lens, which is circular. My guess, therefore, is a very small light leak at the lens-body attachment being internally reflected 'somewhere' in the body and the reflection ending up on the sensor. A second possibility is that the light leaking in is reflected in the circular lens barrel (likely near the optical exit of the lens) and arriving after reflecting off a curved inner surface in the lens. Note that since all lenses have circular construction, any lens would be prone to this, but one might expect that the shape/intensity would vary from lens to lens to some degree. Mr Harris doesn't mention this, so that's why I have my doubts and place this possibility in 2nd place.
Cause of the light leak could be a lot of things. Several come to mind as non-proven hypotheses: some misalignment of the lens mount due to physical shock (Mr. Harris noted hard use of the camera body) or just normal wear and tear or possibly the degradation of a gasket or seal due to harsh conditions (e.g. salt spray).
There. I've made a complete fool of myself. Now it's your turn :-) :-) :-)
I like the logic on the curvarute of the image flaw, however. I'm thinking an unfiltered, unregulated light leak would produce a brighter/ more intense artifact in the image.
I'm going to admit I'm torn between Occam's razor theory[the simplest explainaton is the best] and something spooky like contaminants reflecting off the back of the mirror during its travel. [thinking that would create a different curve pattern though]
Ok: i'm setteling on the theory that the canned air, while it did not damage the sensor, deposited an arc shaped pattern of debris (or a hair) on the sensor creating a differentce in the light reception of the sensor.
Well, Matthew, now we can look foolish together.
Not a bad thought at all. Given the propensity of junk on the sensor to create gray dots and streaks rather than lighter ones (at least that's what happens when I get dust on my sensor), I'd like to expand your idea to include an out-of-focus "something" like a hair blown in and stuck somewhere in the light path in front of the sensor as a potential cause. Thoroughly out-of-focus items, like thin weeds in front when shooting a bird beyond them, can create very soft, curved, lighter-than-the-rest-of-the-picture blurs. So, if we had something thin and hairlike in the camera body, it might be capable of making such a blur.
Mr. Harris probably wouldn't have started this to lure us to our doom if the explanation were mundane, so thinking of weird possible causes, e.g. your reflections during mirror travel, is a worthy enterprise. If you hear hoofbeats behind you, now and again it will be zebras instead of plain old horses :-)
All of the shots in the article are in fairly sharp focus. Just curious - what does the arc look like under the necessary conditions for it to manifest itself when the image itself is purposefully shot out of focus? And does it follow the same pattern of sharp/soft edges during small/wide apertures when the image is deliberately shot out of focus?
Also, is the problem still evident when shooting video?
Just one thing, I am not sure about the half arc you are getting and is it always there, but did you try a lenes shade?
Thank you for the feedback!
He's probably adding that curve on Adobe Photoshop Lightroom or has scraped this curve in his filter to make people think of reasons that are totally to complicated. I like thinking outside the triangle.
I wish I was that deviously clever Caleb...I promise, the answer to the question is coming soon...
I don't think the problem is "the moving mirror" since the mirror is already all the way up (and then not moving) when the shutter opens.
My bet is a leak or an internal reflexion. I it was a leak it sould be mor noticeable with longer expopsures, so the internal reflexion y my most favored guess. I know it is already published, but if I'm wrong, it will be obvious I didn' read the aswwer before writing this. If I'm right y can only swar for my innocence. I'm going to read the answer right now.
Regards an thanks to evrybody.
R.O.
Thanks Mike...nobody would be more foolish than I, had I given up my camera thinking that the sensor was damaged when it wasnt. Appreciate the feedback!
Thanks for the thoughtful response Matthew. I have been reading however about flexible (curvable) sensors....
Hello John...
In my workaday life before retirement, I was a process development engineer in the semiconductor industry, and I've actually worked on integrated circuits (which is what a sensor is) on flexible substrates. The challenges are formidable and I wouldn't hold your breath waiting for a consumer-priced camera-sensor-sized one showing up any time soon. In any case, your camera with the light arc didn't have a curved sensor (unless you really gave it a whack :-)
No doubt camera makers will continue to look into flexible sensors, however. Some technical advantages, such as being able to shape the sensor to fit the curved surface of focus of any lens attached, are not really possible any other way.
You might also look into the most recent issue of "The Economist" (Science and Technology section) to see some other fascinating things going on with sensors...in this case an almost "cameraless" sensor. Again, don't hold your breath, but it's interesting.