Spot in photographs

<p>I have a Nikon D300 with 18-200mm and 70-300mm lenses. I am continually getting an out of focus black spot at the top of the frame in all the photographs. I have checked the mirror & back and front of both lenses and cannot find anything that might be causing this. I have run out of ideas. Any help would be appreciated.</p><div></div>

<p>Take a picture with the lens wide open. My D100 has a few spots on the sensor (filter actually) that start showing up around f8 and up. It could be dirt there.</p>

 

<p>Dust on the sensor. Take a look at <a href="http://www.bythom.com/cleaning.htm">http://www.bythom.com/cleaning.htm</a> for more information.<br>

-mike</p>

<p>It looks as though you have a 20 lb dust-bunny parked on your sensor. Time to give the sensor a cleaning. The bunny looks to be so large that you'd have little trouble seeing it if you remove your lens, set shutter speed to 'B', press and hold-down the release button and peer inside. Best to start with a puff of air from a Rocket Blower. Do not use any type of compressed ('canned') air. Do not touch the sensor with anything unless you know what you're doing.</p>

<p>Sensor-cleaning materials are readily available. Rather than paying someone to do the cleaning it's quite practical and economical to acquire the proper materials, learn how to do it and do the work yourself. Sensor-cleaning is part and parcel with digital cameras and lens-changing. Again, before touching the sensor with anything, learn the proper methods and procedures. Worth repeating: do not use any form of compressed air.</p>

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<p>"<em>The bunny looks to be so large that you'd have little trouble seeing it if you remove your lens..."</em></p>

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<p>It's smaller than you think, about 0.25mm (1/100in) by my calculations. :)</p>

<p>But yes, it's dust on the sensor filter.</p>

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<p><em>I have checked the mirror & back and front of both lenses and cannot find anything that might be causing this.</em></p>

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<p>For future reference <strong>nothing</strong> that is on the reflex mirror, even if it were the size of a baseball, will form an image in your final photos. The mirror is up and out of the path of image forming light when you take a photo.</p>

<p>Also, with the exception of a few lenses with a very short focal length, dust on/in a lens needs to be really bad to cause a distinct "spot" on your photos.</p>

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<p>set shutter speed to 'B', press and hold-down the release button and peer inside.</p>

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<p>The D300 has a mirror-up for cleaning function. I would just use that.</p>

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<p>For future reference <strong>nothing</strong> that is on the reflex mirror, even if it were the size of a baseball</p>

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<p>Just to be sure, do not try to get smthng on your mirror with the properties of a baseball.. :-) , it WILL show on your pictures if you do.. ! ;-)</p>