Reddish Spot in Center of Image (Flare?)

[Tom V]

Disclaimer: I hate to call this spot thing a full-fledged problem yet. I don't quite understand all the conditions it appears in.

I've noticed in several shots, an unwanted reddish flare in the center of the images from my digital camera. I don't recall ever noticing it before in images made with my film camera. I do not think it is a spot on the sensor (I have dust, but they are grey blobs, much smaller, and move around occasionally. I notice it when I have a dark subject surrounded by lighter areas.

Attached is a sample. I could very easily see it on the S2's LCD after the picture. On my previous motorcycle shots (one of which is detailed here: http://www.s2pro.com/forums/showthread.php?s=&threadid=161), there was a reddish area in the middle of the bike, which my client pointed out to me after the ads ran in magazines. I looked, and found it in a lot of images I have taken. The spot is always reddish. Once it was pointed out to me, I knew what to look for, and I notice it a lot - only with image taken with my 50mm lens. I will have to do tests and specifically look for this flare with other lenses.

In the attached image, depending on your monitor, you may be able to see the reddish area dead center in the image. I copyied and pasted the center section down and to the left in order to outline and emphasize the flare. I outlined the flare as a hexagon, but more likely, the unseen bottom edge would make it a seven-sided shape, the same as the Nikkor 50mm ƒ1.8 lens' aperture that was used.

Flare is unwanted non-image-forming light in the frame. The lens is clean, and the Nikon L37c filter is so clean, I could hardly tell it was on the lens.

All the images I have noticed it on were taken in studio situations, using studio strobes, no ambient light except for the tungsten modeling lamps, and no light falls directly on the lens except that from the subject. There is no hole in the back of the camera that I am aware of. The images were taken at ƒ8 to ƒ13, all at 1/125 or 1/180 in M (Manual) Mode. There is no preflash or TTL monkey business going on.

My gut feeling is that this is caused during exposure by light reflecting off the sensor, back onto/into the rear lens element, then reflecting back onto the sensor - forming the unwanted flare. The 50mm lens has a fairly flat rear lens element. The sensor is a disco inferno of diffracted spectral reflective shine. Maybe, just maybe it is too shiny for its own good.?

Anyone else notice a reddish (or other color) spot in the center of their images?

[Debby1]

No, havent noticed THAT thank god.

thats terrible

Deb

[Kanchan]

Tom,

Had a similar problem, I noticed a red/white on one of my photos. When blown up it turned out to be a dead pixel.

Have you tried Dead Pixel Test, there was a link to it on the Digital Photo Review Site, if you can't find it i'll try and send you a copy if you want.

I contacted Fuji in U.K. They advised me to contact the retailer who replaced my camera.

Regrds John

[Andre]

I notice a similar effect when I use my UV filter. Could be your filter is causing it - maybe reflecting back and forth like you suggest.

[Kanchan]

Tom,
Apologies for earlier post, wasn't until I looked at on my destop that I saw the flare, Far to big to be pixel problems.
John

[Swampy]

I've run into a similar problem, 1 of them I can guess. It's the Sun glaring, but from the angle, I wouldn't suspect it as much, but then again, I'm new to Nikon, new to professional digital. Here's the "sun" glare I'm talking about that probably doesn't have anything to do with what you're experiencing, but it's on a bunch of my pictures from different angles, different zoom levels. Lense was a Nikkor 24-120mm. The next picture is more interesting though.

[Swampy]

Now this one, while it looks like a dead pixel, it isn't. I've got two of the exact same shots (a car drove by just at the right moment on the first time) with the same exact spot (I am on a tripod). Same lens - 24-120mm Nikkor. I blew up the spot that's in the middle of the picture and inset it at the bottom left. NOOOO REALLLY?! :)
At first, I thought someone had a laser pointer up there or something like that. It couldn't be the glare, I was shaded by a house behind me and it was sunrise, as you can see in the previous picture above with the sun directly behind me. I've had similar glares to the first one even when taking long exposures of city lights, but only with this lense.

[Tom V]

I am starting to think that my central, aperture-shaped, reddish flare is caused by my 50mm lens or the filter that is on it. Thre reason I never noticed it before on my film camera is because I very rarely ever used the 50mm on my film cameras.I have only noticed it on severely backlit subjects. Why it is red is a mystery.

Swampy's red hot spot looks very strange. Could it be a shiny nailhead on the wall that caught the sunlight just right? Could it be an anomoly in the file, caused when the RAW file was being processed off the sensor? Could it be a shiny little bug that flew between the camera and the house that caught some direct sunlight? Could I be more wrong? Could it be the alien Predator scoping out the neighborhood?

Swampy: If you don't mind me asking, if you were using a tripod, why is the image so un-level? Wind? or -- is it because the camera is level and the house is tipped?

[Swampy]

Originally posted by Tom Voegeli
Swampy's red hot spot looks very strange. Could it be a shiny nailhead on the wall that caught the sunlight just right? Could it be an anomoly in the file, caused when the RAW file was being processed off the sensor? Could it be a shiny little bug that flew between the camera and the house that caught some direct sunlight? Could I be more wrong? Could it be the alien Predator scoping out the neighborhood?

Swampy: If you don't mind me asking, if you were using a tripod, why is the image so un-level? Wind? or -- is it because the camera is level and the house is tipped?

Especially on the second photo, I don't understand why that red dot would be there twice in the same place. Doubt it would be a nail. 32 year old houses with plenty of coats of paint. :) I'm thinking that the guy who lives in that house is under federal protection and was found out and a sniper was waiting for him to come out on the balcony to look at the damage to his house.

Why the image is crooked. Hmm. It's 7am Tuesday morning. Sunday was my Bday and did some exausting things which also included drinking just a little, hardly any sleep that night, 35-104mph winds kicked in at 10pm that Sunday night, kept going until Wednesday morning relentlessly (as you can see by the two different pictures above). Didn't sleep pretty much from Sunday morning 4am (woke up early for some unknown reason) until Wednesday. I was tired. I heard that we couldn't get out of our neighborhood because of a big tree across the road, so I grabbed my camera, took some pictures of a big limb across the street from me, went around the corner and took another branch (laser pointer picture) (that house got hit twice in 24 hours), then walked a little further to take pictures of the guys chainsawing up the one blocking the road to see if I could send it to one of the main papers to get my name in the paper for the heck of it. My mind wasn't really clear at the time and I was on a slight hill. The other big mistake was the manual setting I used for the chainsaw guys (not to mention I didn't have MY new lens yet and I really hate the Nikkor 24-120mm that I had to use for those shots). I am agreeing with everyone's opinion about that lens. Throw it in a closet and forget about it, especially for backlit situations (the chainsaw guys).

Anyway, I live in a forest of break away trees. Eucalyptus trees to be more precise. I have 50 or so on my property (See http://theswampbbs.com/homechanges.htm) and it's really hard to sleep when all you can hear is howling wind and trees all sounding like they're coming down. Part 3 next post....

[Swampy]

So this one guy, across the street from me, he's like that one guy everyone knows. Everything that can, will go wrong with this guy. For 4 years that I've been here, this guy's house has always been nailed by a tree everytime the winds come up. This wind storm was no exception. He got it twice. He gets hit so much that when the storm hit Sunday night at 10pm, he promptly packed the family up and split at about 10:15pm until the next morning. Yup. He got hit. No biggie, 50 pounds of branch hit the corner of his house and bounced off. The corner of his master bedroom mind you, but still, no visible damage. The next day during the wind storms, he gets it again. Much bigger this time, but believe his luck or not, it doesn't appear to have damaged the house. See picture below (The house is LEVEL, ok???? and NO, the street isn't. One or the other, but you can't have BOTH, OK!? :P).

This guys luck is- I see him packing and basically moving out. I talk to him and he tells me that the water pipe under his kitchen (in the foundation) cracked and is leaking and pushing the foundation up. He just laid some REAL nice wood flooring in that kitchen. Bad luck? Oh no. More. So, 2 weeks go by and the insurance company fixes it (they even put his family up in a hotel for the duration). His grass dies cause it's summer and the water is turned off. Nooo. There's more. They get moved back in and start replacing the windows and sliders and stuff and putting the kitchen back together. 3 days later, he's packing up and moving out again. Talk to him again. Water pipe didn't get fixed right. It broke AGAIN. Didn't he just get the wood flooring back in? Yup. So bad luck over? Nope. He's gone for a while now. A few weeks. And this time I don't see anyone working on the house. I finally see him about a week and a half later than that. Talk to him. Insurance company is disputing the work and won't authorize it to be fixed. Anyway, Bad luck guy has to take the insurance company to court to get them to do it. Court system is slow. Finally, 2 months later, they move back in and, well, all he's been worrying about since is wind storms. Rightly so...

[memobug]

I used to get a similar ruby flare with my e-10 when light bled through the back of the eyepiece and fogged the ccd. Now that camera has a beamsplitter, not a mirrorbox, so s2 should be immune from this, right??

What's that little plastic finder cover that came in the box for then? Hmmmm.

Regards,

Matt

[lightwrangler]

Tom's post in another forum reminded me of this, so I thought that I would share my experience. The attached sample is from a S2 with a Tamron 90mm (non Di). No lens filter. I get the same kind of center spot with the same lens on a D70 only in that case the colour is greenish and not pinky. In terms of lighting, I have used only one softbox overhead and relflectors. All of the out of frame white has been covered with black cloth to remove flare. Yet as you can see I still get it. The interesting thing is that I get this with the 50mm 1.8 too. BUT, I don't get it with the Tamron 28 -75mm Di. My questions are; Could this be flare from the rear element of the two non Di lenses? Light bounces off of the chip and flares off of the rear element? Does the Di lens have a coating on it that reduces this? Although both non Di lenses are sharper than the zoom, I end up using the zoom for things on white due to this phenomena. Any help would be appreciated.

Cheers,
Adrian

[Theo2005]

Just tested my Nikon 50mm/1.8 (made in Japan btw) for this phenomena: nothing found, no reddish centre.

As some of you might remember I never use filters on my lenses, unless really needed in a functional way.

I tested it with and without backlight.

Update: tested it with flash: no difference, no red spot.

Theo

[Igor]

Adrian, I had the same issue only with one of my 100+ lenses, Tamron 90mm f/2.5 AI mount. The reddish spot was on every frame shot with a flash.
I couldn't figure what it was caused with so I sold it.

[lightwrangler]

Well, still a mystery to me. I don't get this spot in other situations; available light, strobe portraits on darker backgrounds, on-camera flash etc, but it is annoying. Products on white no-seam is a fairly regular assignment. So I will sell my 90mm (lightly used, about 4 years old) and look for another macro. Experience tells me that 90mm is about as long as I like to go for a lot of my work, so I am hesitant about a 105mm. I used to have one, but it was an older AI and wasn't S2 compatible. Hmmm, time to go shopping. :baldy:

BTW, my 50mm 1.8 is a Chinese Nikon lens, so there could be a difference there. I may have to look for a Japanese version. :mad2:

Honestly, unlike many people, I would like a minimum number of lenses. I like a small kit, but I guess it's all relative.

Cheers,
Adrian

[Igor]

Yes, it's relative indeed. If I was a pro, I'd cut my stock to 3-5 lenses.
Re. 90mm lens, my Tamron AF 90/2.8 doesn't have this problem.
Vivitar 90mm also works great with any flash/lighting...

[NRA]

My 85mm 1.8 was a pain with the red area in the middle on my S2 and D2x. I cant remember it a problem on my slr/n though. So, it had to go and was replaced with a 85mm 1.4, and so far no problems.

Nigel

[lightwrangler]

Yes, it's relative indeed. If I was a pro, I'd cut my stock to 3-5 lenses.
Re. 90mm lens, my Tamron AF 90/2.8 doesn't have this problem.
Vivitar 90mm also works great with any flash/lighting...

Igor, this is interesting ... the photo I showed you is with my Tamron SP AF 90/2.8. (The same lens as yours?) As I said this is the only situation in which I get the pink spot. So you might try your lens in a similar situation and see if it happens to you.

Damn handy lens this one. I will have to test the Di model, to see if it has the same problem.

Cheers,
Adrian

[Igor]

Adrian, now it seems to me it can be a D70/Tamron 90 problem. Because I had this issue with my late D70 too. Can't check it now, as I don't have a D70 anymore :(

[fujifilmnut]

What red spots? All I see are legs. :) :) :) :) :) :)