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MickeyCT
27th of December 2009 (Sun), 21:13
I'm hoping you folks won't object to my posting a question about a Panasonic P&S. I didn't know where else to turn.

I bought my daughter a Panasonic DMC-TS1 for Christmas and many of the pictures have white or colored circles, or more correctly pentagrams, making them unusable. I've tried to find a pattern to help figure out what's causing it but no luck.

Any ideas? Is there something wrong with the camera or is this something fixable?

I'm considering returning the camera to Panasonic and getting something else. Here's a link to one of the pictures.
http://api.photoshop.com/home_4a20fa23f4c741d59885e9ff217c4b11/adobe-px-assets/25d4acc28ef74959a7946e02de8db4ef

Mark1
27th of December 2009 (Sun), 21:22
Looks like a dirty camera to me.

nardes
27th of December 2009 (Sun), 21:43
It’s difficult to tell from the small photo, but looking at a couple of the artefacts, they appear to show the pattern of diffraction rings? There appears to be a central spot surrounded by concentric 5 petalled “rings”? If the iris is a 5 blade diaphragm this might explain the 5 petalled “rings?

I have seen (round) diffraction patterns (using telephoto lenses) from very bright, point sources in the background of photos, but nothing quite like this?

Can you post an enlargement of a couple of the clearer patterns?

Cheers

Dennis

MickeyCT
27th of December 2009 (Sun), 22:37
Does this help?
http://api.photoshop.com/home_4a20fa23f4c741d59885e9ff217c4b11/adobe-px-assets/81e309cae3e7475a8a69d27d99b55f5a

Jon
28th of December 2009 (Mon), 06:00
You're only seeing it with flash, right? You're seeing the flash reflected off dust in the air. Not the camera's fault.

nardes
28th of December 2009 (Mon), 06:56
These patterns look very much like the diffraction patterns produced by out of focus point sources.

Here is a photo I took of a Pelican and the water in the background had bright, point like reflections which appeared as diffraction patterns.

When you look at out-of-focus stars through a telescope, you can see similar patterns. The objective lens of a telescope is round so the diffraction rings appear round and concentric. At sharp focus, you only see the point like star (simplistically) but as you approach focus and then pass through it, you would see the concentric diffraction rings. The out-of-focus diffraction rings in my photo appear octagonal, suggesting that the iris has 8 blades, whereas in your lens, there appear to be 5 blades?

So, at face value, a candidate for these shapes are out-of-focus point sources somewhere in the optical train, although I have never seen so many, so widely dispersed, both in front of and behind the main subject?

Cheers

Dennis

MickeyCT
28th of December 2009 (Mon), 12:59
Jon: So, if these are caused by dust particles in the air, then how come none of the other cameras used during the day have the same issue. (Yes, it seems to occur only when flash is used.) This was Christmas Day and 20 people in the house and quite a few different P&S cameras of different makes and complexity, plus my 20D. It's only her new camera that had the issue. She even switched to her old camera Fuji Finepix F10 for a while and that had no problems either.

Dennis: I assume your comment about "out-of-focus point sources somewhere in the optical train" might also refer to dust particles.

Is there anything we can do about it? House had been recently dusted and vacuumed. :)

Why would this camera pick this up when others don't?

Mickey

Jon
28th of December 2009 (Mon), 13:12
The closer the flash is to the lens, the more likely it is to happen. It's like "red-eye" in that. And looking up that camera, I'd have to say that yes, the flash is very close to the lens.

dwminer
28th of December 2009 (Mon), 14:06
Well the pentagrams shape is a product of the iris and/or shutter. As for as the spots go and these are only thoughts, water spots on the lens, particles in the air close to the lens, but these have already been suggested.

nardes
28th of December 2009 (Mon), 15:51
It does seem odd that only 1 camera is picking up these patterns? The colours of the out of focus pentagrams are a little puzzling. Your cropped enlargement appears to show a red, green and blue diffraction pattern whereas all mine on the pelican shot appear white (RGB combined).

The sensor (chip) has does have a built in RGB array of filters (the Bayer Matrix) – is there a connection here? Surely these “particles” aren’t so close to the sensor such that they only illuminate the pixel below each R, G or B filter of the Bayer Matrix?

Another thing that puzzles me is that I’ve seen these patterns mostly on long focus lenses (+200mm), whereas it looks like you were shooting at the wide angle end of the lens?

Cheers

Dennis

MickeyCT
28th of December 2009 (Mon), 15:51
Thanks for all the help and suggestions as to cause.

Now, do I return the camera and try to find a waterproof P&S with the flash further from the lens or is there some post processing trick that might easily remove this, sort of like the red-eye fix in Photoshop and Elements?

Jon
28th of December 2009 (Mon), 16:00
I don't know of any easy post-processing trick, since they're going to be between the camera and the subject so any fix would mean trying to recreate whatever was behind them. So I think your choices are to live with it (maybe try some shots in another location and see if it happens or if there might have been something about the environment that was a contributor) or find another camera that's "waterproof". From the Panasonic site, with a 10' depth limit, I don't think I'd call that "waterproof" - more "splash-proof", you might want to look for something with a deeper limit. Canon's PowerShot D10 has a 33 ft (10 meter) limit. I believe Pentax makes some waterproof, or at least splash-proof models, too.

hnikesch
28th of December 2009 (Mon), 16:03
I agree with Jon, I have has similar issues with dust in the air close to the camera. My camera also has the flash close to the lens. I get this about 4 or 5 times a year

tkbslc
28th of December 2009 (Mon), 16:39
It is out of focus dust reflecting flash light back to the sensor. I have had cameras that are worse for that problem than others - like my second digital camera (back in 2002) - the Fuji A201. Could not shoot it indoors for that reason. My CAnon SD1100 does it more than my Casio Z70 or Fuji S700 did, but still not very often. The old fuji A201 was literally 95% of indoor shots. So I feel your pain. I ended up getting rid of it because I did not feel confident using it indoors with flash. Honestly, I would return it because it won't get better.

MickeyCT
28th of December 2009 (Mon), 16:45
Update - I just talked with Panasonic and pointed them to this thread to see the pictures. They think it is dust or particles in the camera itself and they are going to replace it for me.

I'll keep you posted. Thanks for all the help.

sue.t
28th of December 2009 (Mon), 17:02
If the house had been recently dusted and vacuumed that could be part of the problem ... both of those activities stir up the dust and get it floating everywhere!

One of my Canons with on-board flash picks those dust particles up easily, whereas the other one with a Speedlite attached doesn't. Same house, same housekeeping.

CameraLens
28th of December 2009 (Mon), 19:22
You have amoebas on the camera sensor! :mrgreen:

Tim Kostka
28th of December 2009 (Mon), 19:28
It is very easy to see if the problem is being caused by dust or something else. Take the same picture twice and if the spots change position, it's most likely dust. Doesn't seem to be what's happening here.

Jon
28th of December 2009 (Mon), 19:29
It is very easy to see if the problem is being caused by dust or something else. Take the same picture twice and if the spots change position, it's most likely dust. Doesn't seem to be what's happening here.He's only posted one picture and a crop from it.

MickeyCT
28th of December 2009 (Mon), 20:52
I don't have the camera as my daughter took it home with her and I've now told her to pack it up. but, I went through the pictures that were taken on Christmas and do have a few that were taken right after each other so they are very close to the "same". I cropped them to approximately the same area which coincidentally is about the same area of the image frame I cropped in the earlier picture. These are near the right edge of the image and I'm really not happy with the quality as I see more distortion than I would expect, however, she's liking the camera except for these spots.

You can see the distortion in some of these pictures. That's me in the red shirt holding my 20D. I'm not sure my brother nor my son would be happy if they saw these either. :)

http://api.photoshop.com/home_4a20fa23f4c741d59885e9ff217c4b11/adobe-px-assets/f4d56fc0b8dc44f69b06b192dd91a7a6

http://www.photoshop.com/accounts/4a20fa23f4c741d59885e9ff217c4b11/px-assets/8f619b7f11f4425484321ec46063460b

http://www.photoshop.com/accounts/4a20fa23f4c741d59885e9ff217c4b11/px-assets/2d62956aaf7f4c62bd42a07cc4cc0348

http://www.photoshop.com/accounts/4a20fa23f4c741d59885e9ff217c4b11/px-assets/660e886e89444bf6a2f5cfba1a7cde9d

MickeyCT
28th of December 2009 (Mon), 20:56
http://api.photoshop.com/home_4a20fa23f4c741d59885e9ff217c4b11/adobe-px-assets/2d62956aaf7f4c62bd42a07cc4cc0348

http://api.photoshop.com/home_4a20fa23f4c741d59885e9ff217c4b11/adobe-px-assets/8f619b7f11f4425484321ec46063460b

http://api.photoshop.com/home_4a20fa23f4c741d59885e9ff217c4b11/adobe-px-assets/660e886e89444bf6a2f5cfba1a7cde9d

MickeyCT
28th of December 2009 (Mon), 21:05
One more thing, house had been dusted and vacuumed, but it was a few days prior to Christmas so things should have settled by then I would think.

Jon
28th of December 2009 (Mon), 22:01
If they were crops from the same area, the spot-causes were definitely moving around. People can stir up dust that you may not have noticed, or that they created themselves (pet dander, dandruff, lint from fibrous clothes, etc.).

Bernoulli
28th of December 2009 (Mon), 22:10
Get a sheet of white paper (I use typing paper) and illuminate it well with a desklamp. Set your camera on a high f ratio, no flash. Hold it just close enough that the entire sheet of paper fills the viewfinder and shoot. The paper will be way out of focus, but that's what you want. Turn the paper a quarter turn and do it again, maybe even four times.

When you view the pictures on your computer, use whatever photo software you have and turn the contrast up and you'll see if those spots are on the sensor or not.

You'll usually find at least a few on any camera sensor, and you can't clean them on a point and shoot. I once returned a brand new SD990 for just that reason.

MickeyCT
28th of December 2009 (Mon), 22:32
Well, camera's going back at this point regardless. I'll try to white paper test with the replacement if we see the same problem.

thanks again, everyone.

pierrot
29th of December 2009 (Tue), 05:58
Droplets on the front of the lens ?