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OK camera smart guys, what are these spots on one of my Bachmann combine images? I first noticed them when I was cleaning up my pix in Photoshop Elements 5.0. First, the white background paper came out muddy looking. But second--and most important, there were these awful spots! My first thought was "sensor dust," but somehow in the final image, the background turned out white and no spots were visible. I won't even ask, "How come?' Instead, I just want to know if this is a dirty sensor, or some other artifact? Now, if I did this right, youse can see the two images. If not, have a nice day.
 

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Well... you seem to have a mobile spot as well. On the side of the coach under the first two windows.. it seems to move down and to the left between the first and second shot.. This is obviously an ektoplasmic manifestation of a spirit that has passed but yet to move on... aka a ghost. Kidding.. It's most certainly some artifact in the image. I'd guess either sensor dust as you mentioned ot it could be that your CCD has some issues and is unevenly responding to light. Seeing as how the one spot "moved" you may have some software issues handling the finished files..

Does you camera have the ability to shoot in RAW format? Try to take a few shots in .jpg or .gif (whatever your default is) then shoot a couple in RAW. Compare the finished images between formats. If the issues are the same then you can elimainte the software, you've got hardware problems..
 

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Dave, yeah, I got RAW. I don't usually shoot it for MLS stuff, but I can--and do when working professionally. Anyway, thanks for the input.

BTW, what's strange is that one photo came out as intended (white background), while the other looked all muddy. I don't know what I did. I have Elements, Lightroom 2, which I did not use for this, and Photoshop 3, which I have yet to load. I waited until a got a new computer, 'cause I would have choked my old one. But now I'm too chicken to load it into my new rig so Photoshop is sitting on the shelf.
 

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Dave, I went back into my file and found a shot taken handheld at about f 8 and about 4 tenths. It was short on depth of fiedl, because the coach is so long, and thus, not too sharp and showing signs of motion. However, I was able to fix most of that in Elements (thanks Adobe) so the edited image don't look too bad. Interestingly, there is little or no sign of any spots, which makes me wonder if it's dirt on the lens, which became noticeable after I stopped the lens down to f 22 and shot using a tripod. Hmm, since it was a slow speed, do you think the spots are noise? Nah. I vote, dirty lens. How about you? Here's the latest image--I hope.
 

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I am a bit confused... (So what else is new?)...
Are both those images from one snap of the shutter and edited on your computer or are they two photos taken in succession?

If two photos (as I now suspect) I figure you took the first one without letting the camera settle on the automatic exposure settings. Press the shutter button "half way" down and hold for a second or so, then press it the rest of the way to actually register the photo. This will ensure the camera is done deciding on all the automatic settings before storing the image. My camera is sometimes slow making up its mind and I am trying to learn to press lightly, hold, press the rest of the way. Sometimes my camera beeps when it is ready (or is it that it beeps if it doesn't think it will take a good photo... never figured that out!) :)
 

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C.T. the first two shots, of which this last one is an example, were taken in succession (exposure set at meter reading, tehn one stop over, as determined by turning the little exposre compensation wheel on the back of my Canon 20D dslr. After examining the shots on screen (by blowing them up) I decided I needed more depth of field, so I got out my crappy tripod, set the camera against it (the clamp didn't fit properly) and held the camera steady while using the camera's self-timer to squeeze off a steady exposure. Then I sent the whole batch to Photoshop Elements 5.0 and fixed one of the tripod exposed images, which are the ones with the spots.

Later, after chatting with you, I went to one of the hand-held images, "Shopped" it for sharpness, etc, and posted same.

BTW, I looked at the rear element of my 10-22 Canon wide angle zoom (this translates to a 16-35 mm when used with your normal, small sensor Canon) and found numerous dirt fleks, which I attempted to clean off.

Now you know as much as I do, which in my case, ain't a lot.
 

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Dust/dirt on the lens. Is this an SLR? I assume from your remarks and the raw abilities. Check the rear glass mostlikely thats were it resides. I did have some dust inside the OEM cheap lens that came with the 20D but that was returned to Canon for cleaning.
 

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Jason, yes, it's a digital slr (now refered to as a DSLR). The lens is a Canon too. In case you were posting while I was replying (see above) I did find some dirt on the rear element.
 

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Joe,

I think it is on the lens. Do you have a UV filter over the lens? if so, there is an outside chance that it picked up something from an oblique angle, particularly if not shaded. Given the artifacts don't seem to be present when you stop it down, that would also suggest dirt on the lens or filter. if you happen to have a photo gray or mid tone background and your lens is a zoom, try this: Take an image at about the mid point of your lens f8 and mid point of the zoom. Zoom a quarter turn. Then on Elements zoom into an artifact that is not in the center of your image. If the artifact has moved, it is a lens issue. If it has not, then it is probably sensor dust.

Hope this helps,
Mike
 

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Mike,

I think you are right about it being "a lens issue." I noticed that on one of the photos--taken at the wide setting--the two spots were toward the left, while on the shot taken at a longer focal length, the spot seems to have moved over onto the side of the coach (as C.T. pointed out). I used my squeeze- bulb brush and blew a few dust specs off the rear element, which will suffice for now. But before I get into any serious photography I think I'll take my 20D and the 16-35 zoom to Canon and have it professionally cleaned.

Now then, if I had $1295, that Canon 50D would be in my camera bag. Also maybe the brand-new Canon 29-320-mm zoom ($700), which is only 6-1/2 inches long. :)
 

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Often spots in photos are related to paranormal activity, often when there is an exchange of energy from an energy source (humans, power lines, batteries, etc) to the entity.

Check for EMF energy in the area where you are taking photos if such spots or orbs appear in your photos. If the EMF is high, this is your cause, or if there is other paranormal activity in the area.

We have had the same problem sometimes in our photos, and I started checking on the net for this a few years back. As our house is haunted, we were able to make sense of the situation.
 

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If it was dust on the chip it would be sharp not blurred.
Take the filter off if you have one on, I suspect that you have a UV fitted.
The optics of digital cameras are far smaller than 35mm and the dust on a filter can almost be within the DOF sometimes.
Also, the lighting is dull and lacks definition which the camera is trying to compensate for.

More light
No dust
No filter
Proper tripod
Less compression
 

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Yeah,Paradise, you make some good points. I did dust off the lens (Canon 10-22 acting as a 16-35 with the mutiplication factor of 1.6) and found a few specks. I may take it to Canon, along with my 20D. However, my understanding is they clean the body for free, and I'm guessing, charge to clean the lens. That's OK, if it's a few bucks (say $20), but if ya go over $50 (I'm just supposing here), then I get payer's remorse. The 16-35 is my favorite lens and I use it 90-percent of the time 'cause I am a wide angle guy. Also, a wide guy, but let's not go there. :)

BTW, I also have a rea; 16-35, from my film days, but never use it. I'm saving it for when I can finally afford a full-size sensor camera like the 5D. IMHO, this is a better piece of glass if sturdiness and heft mean anything.
 

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Ive had spots due to the sensor in the camera getting dirty. I have a place locally that services Canons and i bought a package of 3 cleanings for $40 bucks. I can deal with that based on how much I use the thing.
 

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Posted By joe rusz on 12/28/2008 12:00 AM
Dave, I went back into my file and found a shot taken handheld at about f 8 and about 4 tenths. It was short on depth of fiedl, because the coach is so long, and thus, not too sharp and showing signs of motion. However, I was able to fix most of that in Elements (thanks Adobe) so the edited image don't look too bad. Interestingly, there is little or no sign of any spots, which makes me wonder if it's dirt on the lens, which became noticeable after I stopped the lens down to f 22 and shot using a tripod. Hmm, since it was a slow speed, do you think the spots are noise? Nah. I vote, dirty lens. How about you? Here's the latest image--I hope.




There are two areas where dirt is problematic on a DSLR - the sensor, and the REAR lens element of the lens. A dirty rear element is more likely to cause spotting than a front element. Generally front element imperfections aren't seen by the "film" as discrete problems (but may cause a haziness), unless they are large and completely opaque. Having said that, you did stop down the lens a lot which *might* make front lens dirt begin to resolve, especially if the lens is designed with some amount of macro capability, or, that was enough to bring rear dirt into the depth of field of the sensor plane (not the same as DOF out at your subject, but related). Clean your lens back and front and shoot some tests on a even surface at f22 or even smaller if you have it. Sensor cleaning is VERY tricky - follow the manufacturer's direction explicitly. Not all sensor cleaning methods can be used on all sensors. They are VERY fragile.

The gray/white background issue is a contrast/brightness/gamma adjustment and if the camera was on auto exposure, the position of the metering sensor on the subject likely accounts for the difference. If the sensor is pointed at the white background it will try to set the exposure to make the white sheet 18% gray (about the gray that's right at the car under the windows in the first picture. The rest of the sheet is slightly lighter because the car itself is dark - averaging, remember). That's what the photo sensor does (which it did). The sensor tries to make the overall brightness of the scene represent an 18% gray luminance. For accurate metering, make sure the center of your viewfinder is sitting on a subject area of medium brightness (grass green, grey tree bark, etc). If the meter is on the extremes - black and white, it'll try to make them gray. The Ford principle - any colour you want as long as its grey :). If your shutter has a "press and hold" feature for locking exposure, then point the viewfinder sensor at a "gray" area of the subject, press and hold, then re-align the composition to what you want and then continue to press down to take the picture. Most SLRs have some variations of this procedure.
 

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The new SLR's seem to handle the dirt far better than the first couple of generations. One of the simple steps to help cut back on dirt within the camera (both on the sensor and lens element) is to turn the camera off before you change the lens. While the camera is on the sensor tends to have a electro static charge and will attract dust like a magnet. If the spots are always in the same location of your image then it is either dust or dried condensation mark. The ccd's tend to generate heat and in the right environment will build up small drops of condensation (a much bigger problem on the first few years of digital backs.) I have been totally digital since 1996 professionally (advertising and catalog only) and the cameras today are a dream to work with compared to when it all started. Unless you really know what you are doing I would always recommend having your ccd (sensor) cleaned by the manufacturer or authorized dealer. There are some really good brushes on the market that will collect the dust and special sensor cleaners that work really well. The trick it to keep the dirt out as much as possible to start with. Turn camera off before changing lenses and change lenses in a clean an environment as possible. Otherwise have fun and shoot away. If you do get the odd dust spot photoshop will have no problem removing the dust.  My Fuji S2 pro still will develop dried condensation marks on the sensor no matter how careful I am, luckily the S5 eliminated almost all the dust problems along with the Nikon D3 and I am sure other new bodies have done likewise.  
cheers
 

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Thanks, Canadians. You guys sure are thorough. I always turn off the camera when changing lenses. I also keep the rear cap handy so I can quickly cover up the exposed elemnet of the lens I'm switching to/with. So far, I've seen no more spots, but I'll wait until I show my "work" photos to my art director. Those fellas can find anything that's amiss.
 
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