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Is this dust on a lens?
Took this clip with a SONY HDR-FX7 (HD Camcorder) https://www.dropbox.com/s/sqggchktz9s0n … s.mp4?dl=0 I noticed that there are white specks when out of focus (very beginning of clip), that disappear at the end (when in focus). What are they? I googled for videos of dust on camera lenses but could only find videos on photo camera lens dust, not camcorders. Mar 23 15 01:43 am Link That is something on your lens catching the light and showing up on the video. A good cleaning may be all you need, unless it's scratches or pitting. In any case, using a lens hood can help reduce the appearance of that sort of artifact. Mar 23 15 02:14 am Link I did inspect the lens and didn't visually see any dust or scratches, inside or out. Yes I did use a lens hood, the one that came with the FX7. I couldn't find anything online with regards to dust and lens for camcorders, which is strange? Mar 23 15 02:22 pm Link Sandra Vixen wrote: Always clean your lens before you use it! Mar 23 15 02:32 pm Link It could be dust, but those look like they might be a little deeper. Was it used at the beach or in the desert? Mar 23 15 04:07 pm Link these spots are amazingly in focus --- maybe something on a filter? Mar 23 15 05:47 pm Link I cleaned the outside of the lens a few times, I took another clip yesterday and it still seems to have dust (focus from infinity to 0.1m): https://www.dropbox.com/s/8xycnjj9fm081 … s.mp4?dl=0 Mar 24 15 03:42 am Link The thing I don't get is that they move independent of the background movement. If it was on the lens, they would be the same movement. It's as if you're shooting through glass (beyond the filter and lens). Either way, clean the front and back of the lens, and the sensor. Shoot some stills as well to compare. Mar 24 15 05:45 am Link I'm not 100% sure either, I noticed the movement too. The FX7 does have NL1 and NL2, and I think it was switched on to NL2. But I had nothing in front of the camcorder's lens other than a lens hood. What about image stabilization? Could that affect it? On board the camcorder, I set it to "standard". Mar 24 15 02:47 pm Link If it was on the sensor, you'd see it constantly. It also shouldn't have anything to do with the stabilization. I'd swear it was dust/smudges on a UV filter. It appears when the sun is at a particular angle (which makes sense) and when the focal point is as far in as it can get (which also makes sense). What did you clean with? Examine the lens (and any filters) at various angles to a light source and see if you can spot anything. Mar 24 15 03:53 pm Link Based on 50 years of experience with both still and motion cameras, I would have to say YES . . . you had some small dust particles on the front surface of the lens. They appear prominently at the beginning when the lens is focused closely and pointed up into the sky (a large light source) and then they disappear as the sun is shaded off of the lens as the camera is being tilted downwards away from the light source. A good lens shade and a clean lens will solve your problem KM Mar 24 15 04:04 pm Link What I noticed is that you began with the camera angled toward the sky, and as you lowered it and brought it into focus the spots seemed to disappear but they actually are not gone, the lighting is just darker so they appear to fade. If you follow a few of them from the light to the dark you will see that they are still there. Clean your lens and what doesn't move is dust or scratches on the lens. Mar 24 15 05:04 pm Link Jamez wrote: True. If you plant your cursor on any spot and play the video you can really see the independent motion. Mar 24 15 05:54 pm Link Ken Marcus Studios wrote: Ken, how did you accumulate 50 years worth of experience with dust artifacts on lenses? After the first ten or twenty years I probably would have cleaned the lens. Mar 24 15 05:56 pm Link NothingIsRealButTheGirl wrote: LOL! and I thought *I* was a procrastinator! Mar 24 15 06:02 pm Link Having looked at it again (and paying attention to the camera model this time), I believe that what you are seeing is related to the image stabilization (especially in the second clip). I could be wrong, but I don't think the lens on this model is removable. So this may be an even bigger problem than originally thought if it was a DSLR shooting video. What's the history of the camera? It's pretty strange to have dust on an inside element of a non-removable-lens camcorder. Edit: I also see a lot of moisture in that second clip. Was the unit ever in the rain? When the second clip was shot; was the camera moved in/out of high humidity differential? My guess is that this camera has seen a few rough moments, and has developed some kind of crack letting in the dust and humidity. Mar 26 15 06:33 am Link |
