Is something wrong with my sensor?

[ariel_green]

<p>I just took this photo on a white piece of paper. I increased contrast so the dust was more visible. I also moved around the camera (D300) so it would not get any paper detail. The aperture was at f22 and it was about a 1 second exposure. There is a lot of dust on the sensor, but I was wondering if anyone knows that that large white spot is on the sensor. I have it marked with an arrow. <br /><br /><br />http://www.flickr.com/photos/greenariel/4560819845/</p>

[Matt Laur]

<p>What lens were you using?</p>

[ariel_green]

<p>Nikon 50mm 1.8. I also took the image with an 85mm 1.8 and got the same results.</p>

[bob_sunley]

<p>Do you have UV filters on the lenses?</p>

 

[francisco_disilvestro]

<p>It could be a stain either from humidity or from oil (lubricant from the camera). It needs cleaning with specialized products. The sensor cleaning function of the camera will not solve it.</p>

[ariel_green]

<p>No I am not using a UV filter on the lens. So I guess I should bring it in for cleaning?</p>

[Matt Laur]

<p>I've seen many examples of the 50/1.8's rear element catching a reflection off of the sensor, and re-refecting it back ... which causes a spot in the center of the image. Try it with a different lens.</p>

[conrad_hoffman]

<p>Yup, the 50mm f/1.8 does that. At least some of 'em. There's nothing wrong with sensor, camera or even the lens. Normally you won't see it, though I've been in situations where it did show up dramatically. I think it was a bright day on the water, and the spot showed up in the sky. It happens on film with that lens design too. It's not related to the filter. There are several variations of 50mm f/1.8 Nikkors with a different radius on the rear element and not all do it. I first saw it with an inexpensive (series E or similar plastic body) one. My older metal and rubber grip AiS doesn't do it.</p>

[akira]

<p>The white spot should be the "hot spot" which always appears in the dead center of the image and can often be observed in the infrared images. It is sort of internal flare.</p>

<p>No dust-off mechanism is perfect: there is no wonder if there are stubborn particles remaining on the sensor. The more you stop down, the clearer the dust will be visible. White paper and stopping down to f22 is the most ideal way to render the dust on the sensor clearly.</p>

<p>In short, I would say that your gears are working just normally and honestly. :)</p>

[walterh]

<p>Did the lens do it or not? Easy to answer - just take the lens off and shoot another image :-)</p>

[bjørn rørslett]

<p>You put the lens in a situation under which flare is almost inevitable. You need to use the longest possible lens hood to shield the front surface from the glare of the surrounding bright areas.</p>

<p>What you observe is a hot spot. Point the lens towards a bright sky, shoot at f/22, and you'll see the similar thing.</p>

<p>Not all versions of the 50/1.8 exhibit this issue. My long-nose early AIS does not (neither in visible light nor in IR), whilst a fairly recent AFD has a weak hot spot in visible light and a fairly bright one in IR.</p>

[jim_momary]

<p>Pretty darn close to dead center, as indicated above.<br>

jim</p><div></div>