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Archive 20095D2: what is going on here???
p.3 #15D2: what is going on here???
Geofn wrote:
Looks to me like when the mirror started up it caught an image of the sun, previously outside of the frame but included in the lens' projected circular image, and reflected it into the viewfinder (hence the flash) and the reflection of the sun off the bottom of the pentaprism then traced the arc-shaped flare onto the sensor through the 50% transmissive mirror. Just a guess, but it's the best explanation I can come up with. All the angles would have to be just right (wrong?) for this to happen, so my guess is that you'll likely never see it...Show more →
I think you're right about the flash OP saw in the viewfinder, but aren't the partially silvered parts of the mirror only in front of secondary mirrors that direct light to AF sensors? The mirror can send odd reflections through the finder as it moves, but not to the sensor. Besides, the shutter wouldn't open until the mirror is out of the way. The artifacts in the file are more likely related to the extreme brightness within the frame and the demosaic effects discussed in the link above.
Looks to me like when the mirror started up it caught an image of the sun, previously outside of the frame but included in the lens' projected circular image, and reflected it into the viewfinder (hence the flash) and the reflection of the sun off the bottom of the pentaprism then traced the arc-shaped flare onto the sensor through the 50% transmissive mirror. Just a guess, but it's the best explanation I can come up with. All the angles would have to be just right (wrong?) for this to happen, so my guess is that you'll likely never see it...Show more →
I think you're right about the flash OP saw in the viewfinder, but aren't the partially silvered parts of the mirror only in front of secondary mirrors that direct light to AF sensors? The mirror can send odd reflections through the finder as it moves, but not to the sensor. Besides, the shutter wouldn't open until the mirror is out of the way. The artifacts in the file are more likely related to the extreme brightness within the frame and the demosaic effects discussed in the link above.
Sep 13, 2009 at 05:17 PM
p.3 #25D2: what is going on here???
I was shooting a wedding using film, and had a bright light in the viewfinder. Ruined the frame (overexposed) and never did figure out what happened. I thought it was somebody's flash, but I was the only one in the area with a camera, and it was dark. Really really dark.
The camera never did it before that, and never did it after that.
The camera never did it before that, and never did it after that.
Sep 13, 2009 at 05:36 PM
p.3 #35D2: what is going on here???
Maybe you would have seen it in the VF if you hit DOF preview, meaning the flare was maybe too diffuse to notice when the aperture was open..?
Sep 13, 2009 at 06:07 PM
p.3 #45D2: what is going on here???
Photon wrote:
Besides, the shutter wouldn't open until the mirror is out of the way.
Yeah, you're probably right about the shutter. I guess the sun's reflection couldn't have reached the sensor after all. Weird phenomonon, for sure.
Besides, the shutter wouldn't open until the mirror is out of the way.
Yeah, you're probably right about the shutter. I guess the sun's reflection couldn't have reached the sensor after all. Weird phenomonon, for sure.
Sep 13, 2009 at 06:58 PM
p.3 #65D2: what is going on here???
^^^ A thread killing question that left 2 people scratching their heads? 
Sep 14, 2009 at 08:55 PM
p.3 #75D2: what is going on here???
slrl0ver wrote:
Daan,
Based on this site:
http://www.insflug.org/raw/guis/
These are two free Mac OSX GUI programs that use dcraw:
http://raifra.fh-friedberg.de/Mac/index-en.html
http://www.chocoflop.com/download_en.html
If you don't mind using the command-line, you can download a OSX dcraw binary and try the options manually.
- slrl0ver
Thanks I will have a look when I can find some time...
Daan,
Based on this site:
http://www.insflug.org/raw/guis/
These are two free Mac OSX GUI programs that use dcraw:
http://raifra.fh-friedberg.de/Mac/index-en.html
http://www.chocoflop.com/download_en.html
If you don't mind using the command-line, you can download a OSX dcraw binary and try the options manually.
- slrl0ver
Thanks
I will have a look when I can find some time...Sep 15, 2009 at 12:56 AM
p.3 #85D2: what is going on here???
When I have had images that were not what I expected, I was able to solve the problem by taking off the uv filter that I had on for protection. I once had a issue using my Canon 85L f1.2. I no longer use UV filters except as lens caps.
Sep 15, 2009 at 05:33 AM
p.3 #95D2: what is going on here???
omarlyn wrote:
+1 ...The internal reflections would undoubtedly be different and could (potentionally) cause flare that would not otherwise be seen with the mirror down. I wonder if you might be able to repeat this phenomenon by setting up a similar shot and switching back & forth from live-view to see if you create the same type of flare.
HTH,
Omar
I think this is correct. Only to add to this idea, more correctly, I think it was the mirror that eliminated the sunlight (flare) that was seen in the photo.
When light is reflected off the mirror, some of the intensity is lost (I think it's a half-silvered mirror, that means it's 1/2 the intensity). Also, dependent on the grains on the mirror, light of certain direction will be more affected and not viewable by your eyes. This fraction is still available to the sensor later of course. When the camera takes the picture, the mirror is flipped up, there is no other optical component that is in the way to the sensor. Thus, the sensor would see the full intensity coming in from the lens.
I think it is a coincidence that you're in the right place with the right angle.
U.C. wrote
When the mirror is down, there are other reflections inside the box than with the mirror up.HTH,
Omar
I think this is correct. Only to add to this idea, more correctly, I think it was the mirror that eliminated the sunlight (flare) that was seen in the photo.
When light is reflected off the mirror, some of the intensity is lost (I think it's a half-silvered mirror, that means it's 1/2 the intensity). Also, dependent on the grains on the mirror, light of certain direction will be more affected and not viewable by your eyes. This fraction is still available to the sensor later of course. When the camera takes the picture, the mirror is flipped up, there is no other optical component that is in the way to the sensor. Thus, the sensor would see the full intensity coming in from the lens.
I think it is a coincidence that you're in the right place with the right angle.
Sep 15, 2009 at 07:34 AM
p.3 #105D2: what is going on here???
A shiny golf ball flying by? But that has to fly so fast that it would probably shoot down a plane. 
The grid like effect looks like when videocam is panned too hard, it may be just the effect of very fast "motion" "seen" by the sensor.
The grid like effect looks like when videocam is panned too hard, it may be just the effect of very fast "motion" "seen" by the sensor.
Sep 15, 2009 at 09:46 AM
p.3 #115D2: what is going on here???
I think it has been said, but the flare looks like a coincidence of timing and angle to the sun and the grid pattern is most likely the result of the demosaicing algorithm. Process the file with a different program as recommended and the pattern will likely disappear. I have a few images taken recently with a CV 15mm heliar on an E-P1. I converted to DNG...viewed in Lightroom, I see the same exact pattern as in your image. Viewed in Photoshop/ACR (which had already been updated to officially support the E-P1), it was fine.
Sep 15, 2009 at 01:09 PM
p.3 #125D2: what is going on here???
Daan B wrote:
What is going on here? Could this be due to internal lens reflections? And what is the grid pattern about? Is it the sensor?
Thoughts?
This maze pattern problem with the 5D2 has been reported several times on dpreview. I believe one user got a new camera from Canon..
What is going on here? Could this be due to internal lens reflections? And what is the grid pattern about? Is it the sensor?
Thoughts?
This maze pattern problem with the 5D2 has been reported several times on dpreview. I believe one user got a new camera from Canon..
Sep 15, 2009 at 08:29 PM