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|| SportsShooter.com: Member Message Board
Dust on the field
Larry Lawson, Photographer
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Portland | OR | USA | Posted: 11:37 PM on 09.05.09 |
->> Having started shooting ncaa football, I'm finding well over half the shots contain what I'll say is 'dust?' on the images. The lenses are clean, and the only thing I can think of is that it's just 'dust' of some sort coming up off the astroturf.
Anyone else have this happen? Some shots with the 300 2.8 are immaculate, others have so much dust/tiny white spots I almost want to just toss 'em, except some are gorgeous tack-sharp. It's frustrating, that's for sure. |
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Dave Prelosky, Photographer
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Lower Burrell | Pa | US | Posted: 11:49 PM on 09.05.09 |
->> Larry,
Two possibilities come to mind:
A. Most current trurf seems to be embedded with ground rubber "beads" about the size of a BB. They seem to kick up at the end of plays when athletes come to a stop of fall hard.
B. Equally possible is a dirty sensor in your camera. Is the "dust" more pronounced at smaller apertures? That's the tell-tale.
Post one somewhere, and I'm sure someone else will offer an opinion. |
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Mark Loundy, Photo Editor
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San Jose | CA | USA | Posted: 3:36 AM on 09.06.09 |
->> Dust on your lenses will not show up as spots on your images. The only place dust can create a hard outline is at the focal plane. The dust is almost certainly on your sensor.
--Mark |
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Tim Casey, Photographer
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Gainesville | FL | USA | Posted: 3:52 AM on 09.06.09 |
| ->> The new synthetic turf fields have sand and tiny bits of rubber to make the surface perform more like grass. Just like you would get dirt or grass flying up behind someone as they run, the rubber and sand gets kicked up as they run. It often adds dramatic effect to the images. |
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Paul Alesse, Photographer
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Centereach | NY | USA | Posted: 4:18 PM on 09.07.09 |
| ->> Can we seem some examples? |
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Daniel Putz, Photographer
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Paul Alesse, Photographer
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Centereach | NY | USA | Posted: 3:22 PM on 09.08.09 |
| ->> I know what the pellets look like when they kick up. I'm just trying to determine whether the dust that Larry is referring to are the pellets or convection current disturbances most noticed in the bokeh. |
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Brad Mills, Photographer
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Falls Church | VA | USA | Posted: 3:37 PM on 09.08.09 |
->> You mention the spots are white. Most Field-turf fields used old tire rubber that is black.
This photo has "white spots" which are water. For field hockey the turf field is watered prior to the match.
http://dbradmills.com/temp/09/UM_FH/images/700_3322.jpg |
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David A. Cantor, Photographer, Photo Editor
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Juliann Tallino, Photographer, Photo Editor
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Port Townsend/Seattle | WA | USA | Posted: 4:49 PM on 09.08.09 |
->> Just a guess without seeing the image, but could it be sweat off the players? I have shots with white specks and it's sweat. Here's an example, I was shooting night football with flash so the light froze the sweat mid air.
http://www.sportsshooter.com/tallino/whitespots/pages/1.html |
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Bradly J. Boner, Photographer, Photo Editor
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Jackson | WY | USA | Posted: 6:11 PM on 09.08.09 |
->> We have a new soccer field and a new football field, and both have these little rubber bits. My understanding is that it's recycled, chopped up tires to give the artificial surface a "springy" feel.
It makes it almost impossible to use a long lens to shoot soccer on a hot day because the heat radiated from it gives far-away objects (like players) a wiggly, "mirage" look. |
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George Bridges, Photographer, Photo Editor
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Washington | DC | USA | Posted: 6:22 PM on 09.08.09 |
->> Since the original post said the spots were white it's not the rubber "dirt" flying up off the artificial turf. Unless the particular field you are talking about has white rubber "dirt" rather than black.
Larry, can you post an example for folks to look at? |
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Philip Bowen, Photographer
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Kampala | UG | Uganda | Posted: 6:32 PM on 09.08.09 |
->> Is this one of those lateral thinking puzzles? "Seven men are in a cabin in the woods, how did they die..."
If you're shooting shutter priority in variable light, that can definitely swing your aperture enough in both directions so sensor dust appears in some images and not others. That mythical white sensor dust. |
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Mark Loundy, Photo Editor
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San Jose | CA | USA | Posted: 1:00 AM on 09.09.09 |
->> Philip,
Spots caused by dust on the sensor are not affected by changes in aperture.
It is possible to see dust on the front surface of a lens with small apertures -- particularly with shorter lenses.
--Mark |
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Kevin Leas, Photographer, Assistant
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Rochester | NY | USA | Posted: 1:46 PM on 09.09.09 |
| ->> Mark - if sensor dust isn't affected by aperture, what is? Whenever I clean my sensor, I always snap the same shot at a few apertures - usually somewhere around 4, 11, and 16. The spots get increasingly dark and defined as I go smaller, and it doesn't matter what lens is on the camera. What am I seeing there if it isn't sensor dust? |
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Jeff Mills, Photographer, Photo Editor
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Columbus | OH | USA | Posted: 2:14 PM on 09.09.09 |
->> Mark, are you sure about your comment "Spots caused by dust on the sensor are not affected by changes in aperture." ??
I don't about your sensors, but the more I stop down the more dust I see on mine.
I usually shoot wide open or close to it most of the time so I never realize how dirty my sensor gets until I have to stop down for a group photo or landscape shot and then see just how dirty it really is.
Point your camera at a wall or sky, take a shot at F2.8 and then a F22 and I think you'll see a lot more dust specs with the smaller aperture. |
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Larry Lawson, Photographer
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Portland | OR | USA | Posted: 11:56 PM on 10.28.09 |
->> Finally got to look back at these - both are from a 30D, same iso, same lens, same aperture, relatively new body & lens, etc. Even though I'm not shooting with it anymore, this dust has appeared from both my 50d and the 1DmkIII.
Example with dust is http://www.millerstreet.net/Dust_ex_1.jpg
without dust is http://www.millerstreet.net/Dust_ex_2.jpg
Sorry it's taken awhile to get these examples up. Again, all comments/suggestions welcome! |
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Mark Peters, Photographer
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Highland | IL | USA | Posted: 12:09 AM on 10.29.09 |
| ->> Sweat |
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Isaac Ginsberg, Student/Intern, Photographer
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Seattle | WA | U.S.A | Posted: 1:24 AM on 10.29.09 |
| ->> yep, 100% sweat off the players. |
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Alan Stewart, Photographer
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Corydon | IN | USA | Posted: 10:37 AM on 10.29.09 |
| ->> I'll go with crap flying up off the turf. I know players sweat, but I've never seen it fly like that before. |
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Jody Gomez, Photographer
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Murrieta | CA | USA | Posted: 11:32 AM on 10.30.09 |
| ->> I don't see the spots on the second image. If it was something on your sensor, it would be in the same place on every file. I think it's something coming up off the turf. Did you check the color of the grass infill? It could be a light color, or it also could be sand. |
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Eric Canha, Photographer
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Brockton | MA | United States | Posted: 11:54 AM on 10.30.09 |
| ->> Sweat or water coming off the jersey. By the end of the first quarter most of those guys are wearing a quart of water/Gatorade down the front of their uniforms. You see the same thing (at least I do) with hockey, and it's either shaved ice or the 1/2 gallon of liquid that has missed their mouth during the game. |
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Paul Nelson, Photographer
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Temperance | MI | USA | Posted: 2:00 PM on 10.30.09 |
->> When was the last time you did clean the sensor? On a 30D I have, I seem to need to clean it after only a few days of using it....the sensor is like a magnet for dust. Depends on how frequently you switch lenses as well.
After reading about this site - "Copperhill" method - (http://www.copperhillimages.com/index.php?pr=tutorials), I've cut down on the issues ten fold over the old methods I've used (always re-buying sensor swabs). I picked up the magnifier tool that has a light on it(just the right size to use on cameras) when I ordered and now it's really easy to check the sensor for dust and SAVE the time cleaning if I can't see anything wrong. I hate to keep shooting many test shots to validate what I can see with the magnifier.
In my mind, nothing worse than having an excellent shot screwed up by a dust spot. Until I replace my older bodies, I'll have to keep cleaning them by hand frequently... |
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Bruce Omori, Photographer
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Hilo | HI | USA | Posted: 11:03 PM on 10.30.09 |
| ->> I think dust spots on the sensor are always dark because they block light, so it looks like dust from the turf to me. |
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