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Archive 2016 · Does anyone know what this is???

  
 
billsamuels
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p.1 #1 · p.1 #1 · Does anyone know what this is???


I was out taking some photos with my Canon EOS 5DSR, came back and after reviewing the photos, found THIS (see photo below).

Does anyone know what it is?

My first question is, does this look like a sensor problem? It's a fairly new camera and I've only had it for a couple of months. It certainly doesn't look like any dust I've ever seen.

Second, if it's not, what is it and how do I get rid of it?

Last thing, it's in every photo I took today in the same place and looks relatively the same. This photos below was cropped significantly so you can see it better. I'm also including the regular photo it was in.

Thanks for your input.
Bill





Cropped photo taken at ISO 500, F/8, 1/800, EF 24-100mm F/4L USM lens







Original photo - the spot is in the right tree limb at the top of the main branch before it spreads out




Jan 21, 2016 at 08:33 PM
EB-1
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p.1 #2 · p.1 #2 · Does anyone know what this is???


I see a hot red pixel. Is that what you mean?

EBH



Jan 21, 2016 at 08:41 PM
Monito
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p.1 #3 · p.1 #3 · Does anyone know what this is???


It's a hot pixel and I think you can map it out somehow with instructions from the camera manual.



Jan 21, 2016 at 08:43 PM
UCSB
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p.1 #4 · p.1 #4 · Does anyone know what this is???


I think Canon bodies can self fix this problem .... but, can't remember how. I think it was something like initiate a manual self cleaning. You might check the manual or call Canon.


Jan 21, 2016 at 08:46 PM
Ferrophot
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p.1 #5 · p.1 #5 · Does anyone know what this is???


I don't think it is dust or something on the sensor. It looks like some kind of processing artifact. I see similar things on some of my shots if I blow them up to 100 or 200%, especially those processed from jpegs. Be aware that the sky is not always a constant blue hue. moisture, temperature gradients often cause differences in tone. Even distant flocks of birds can be mistaken for sensor dust.
The halos around some of the limbs and fork in the tree suggest some processing adjustment is needed.

edit. I was looking at the wrong thing. yes looks like a hot pixel. I have one on my 6D, but as i rarely see it I don't worry about it. I think these can be mapped out in camera.

Edited on Jan 21, 2016 at 08:53 PM · View previous versions



Jan 21, 2016 at 08:48 PM
Monito
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p.1 #6 · p.1 #6 · Does anyone know what this is???


See Appending Dust Data page 375 of the manual. It doesn't mention hot pixels, but I think that is it. It might only work on Raw images processed by Canon DPP.



Edited on Jan 21, 2016 at 08:55 PM · View previous versions



Jan 21, 2016 at 08:52 PM
EB-1
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p.1 #7 · p.1 #7 · Does anyone know what this is???


UCSB wrote:
I think Canon bodies can self fix this problem .... but, can't remember how. I think it was something like initiate a manual self cleaning. You might check the manual or call Canon.


Like this.



EBH



Jan 21, 2016 at 08:53 PM
billsamuels
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p.1 #8 · p.1 #8 · Does anyone know what this is???


But should I have a hot pixel on a new camera?


Jan 21, 2016 at 10:34 PM
scalesusa
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p.1 #9 · p.1 #9 · Does anyone know what this is???


A hot pixel can be one that is turned on all the time, or one that only appears when shadows or dark areas are boosted greatly.

Generally, when shooting raw, Adobe lightroom will remove them for you, a little NR will do it as well. If you are seeing them on jpeg images, you can try to get the camera to map them out.






Jan 21, 2016 at 10:42 PM
billsamuels
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p.1 #10 · p.1 #10 · Does anyone know what this is???


scalesusa wrote:
Generally, when shooting raw, Adobe lightroom will remove them for you, a little NR will do it as well. If you are seeing them on jpeg images, you can try to get the camera to map them out.


Yes, those were jpgs. I haven't checked the memory card with the raw images yet to see if they also had them as well (real nice to have a camera with dual memory cards).

Anyway, I'll have to see if the owner's manual has the instructions to map it out.



Jan 22, 2016 at 12:01 AM
billsamuels
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p.1 #11 · p.1 #11 · Does anyone know what this is???


Wow, what would I look for in the Canon owner's manual


Jan 22, 2016 at 12:04 AM
UCSB
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p.1 #12 · p.1 #12 · Does anyone know what this is???


EB-1 wrote:
Like this.



EBH


Yes, that is it.




Jan 22, 2016 at 12:37 AM
billsamuels
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p.1 #13 · p.1 #13 · Does anyone know what this is???


I did this before so it's not that. I'll call Canon in the morning.


Jan 22, 2016 at 01:30 AM
dhphoto
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p.1 #14 · p.1 #14 · Does anyone know what this is???


Hot pixels have been around since the first digital cameras, you have 50 million pixels, one or two are bound to fail

If you use Lightroom to process your RAW files they will be mapped out automatically.

It's certainly not a camera fault



Jan 22, 2016 at 02:43 AM
Gochugogi
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p.1 #15 · p.1 #15 · Does anyone know what this is???


All my new cameras shipped with a few hot pixels. My FF had the most and the croppers less. You cam map them out in DPP too if your choice 'o poison.


Jan 22, 2016 at 03:39 AM
Chuck Brittain
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p.1 #16 · p.1 #16 · Does anyone know what this is???


I probably have a dozen hot pixels on my 40D. They show up most on long exposures or if I push the shadows. I've yet to see any on a properly exposed shot.


Jan 22, 2016 at 04:34 AM
jimmy462
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p.1 #17 · p.1 #17 · Does anyone know what this is???


billsamuels wrote:
>snip<

Does anyone know what it is?

https://www.fredmiranda.com/forum/ufiles/44/1246544.jpg

>snip<
Bill


Hi Bill,

I'm suspecting that this red spot is looking a bit worse than it actually is due to the heavy-handed over-sharpening in that cropped image...the white haloes around all the dark branches when viewed at pixel-level are a "dead give-away". Any chance we can see a SOOC crop of this same section? It'll help identify just how bad the (likely) hot pixel is actually affecting things!

Thanks!



Jan 22, 2016 at 07:45 AM
Imagemaster
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p.1 #18 · p.1 #18 · Does anyone know what this is???


jimmy462 wrote:
Hi Bill,

I'm suspecting that this red spot is looking a bit worse than it actually is due to the heavy-handed over-sharpening in that cropped image...the white haloes around all the dark branches when viewed at pixel-level are a "dead give-away".



Good call, Jimmy.

Tony



Jan 22, 2016 at 11:56 AM
gdanmitchell
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p.1 #19 · p.1 #19 · Does anyone know what this is???


My first thought was "hot pixel." It presents virtually all of the symptoms: a primary color (either red, blue, or green), in the same spot in every photograph, etc.

The one confusing thing, though, is that if we are looking at a 100% magnification crop the pixel should occupy exactly one pixel in the image — but this one seems larger and longer in the vertical direction. That seems a bit more like an optical thing, especially if it is near the edge of the frame.

To make sure, make an exposure in raw mode, perhaps shooting a monochromatic, featureless subject, and then look at the file in your raw converter without applying any sharpening or other post-processing. If that turns this into a single-pixel artifact, you have a hot pixel.

Normally, most raw conversion software (and certainly that from Adobe) will map out these pixels and you'll never notice them again. I don't know what the current policy is, but it has always been the case that manufacturers (of sensors, computer screens, etc.) set a certain maximum number of acceptable bad pixels, below which they won't replace the unit. If so, make sure that you are set up to have your post-processing software manage it and you'll be fine.

One more thing. Underexposing high ISO exposures can make such similar noise issues more visible. I didn't check your file, but could this play a part?

Dan



Jan 22, 2016 at 12:06 PM
Monito
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p.1 #20 · p.1 #20 · Does anyone know what this is???


gdanmitchell wrote:
The one confusing thing, though, is that if we are looking at a 100% magnification crop the pixel should occupy exactly one pixel in the image — but this one seems larger and longer in the vertical direction.


The coding-decoding process of JPEG smears out single pixels. This is not ordinarily noticed because almost all pixels are near similarly coloured pixels. But with a hot pixel the JPEG smearing is more noticeable.



Jan 22, 2016 at 12:21 PM
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