What are those red dots?

sajah · 04-09-2009, 12:59 PM

After further testings, I found out that this thing occurs with my other lenses too. So this is definitely not a problem with the Helios lens but my *istDS sensor. Sorry for the misleading and thanks for all the kind answers.

@quension: the traffic light is the one which is composed of a lot of smaller red lamps, I'm not sure it correspond to old or new one in your term.

Quension · 04-09-2009, 03:55 PM

Originally posted by sajah

@quension: the traffic light is the one which is composed of a lot of smaller red lamps, I'm not sure it correspond to old or new one in your term.

Hm, I haven't seen that kind. It sounds like a newer LED type though.

Glad you found where this effect is happening, even if not what's causing it.

my_photography · 04-09-2009, 04:23 PM

Interesting finding. Does the "llight" shows up very often or only under certain condition?

sajah · 04-09-2009, 09:46 PM

Originally posted by Quension

Hm, I haven't seen that kind. It sounds like a newer LED type though.

Glad you found where this effect is happening, even if not what's causing it.

Yeah looks like a lot of LEDs.

Originally posted by my_photography

Interesting finding. Does the "llight" shows up very often or only under certain condition?

It seems that it shows up all the time.. From all the pics I took yesterday at a traffic cross, the only reason I didnt always got the effect is because the red tail lights weren't always on, just when the drivers hit break pedal (I only tested during daylight)

AndrewG NY · 04-13-2009, 02:56 PM

Originally posted by sajah

One more thing, when I open the image in photoshop, I notice that the red spots have almost white color in red channel and absolutely black in the green and red channel. Thoughts?

Nice observation, but not at all surprising. I assume you meant black in green and blue channel. A bright full, even red like that would be pretty close to RGB(255, 0, 0).

sajah · 04-13-2009, 11:20 PM

Eh yea, my mistake

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04-09-2009, 12:59 PM	#16
sajah Senior Member Join Date: Mar 2009 Location: South Korea Photos: Gallery Posts: 275 Original Poster	After further testings, I found out that this thing occurs with my other lenses too. So this is definitely not a problem with the Helios lens but my *istDS sensor. Sorry for the misleading and thanks for all the kind answers. @quension: the traffic light is the one which is composed of a lot of smaller red lamps, I'm not sure it correspond to old or new one in your term.

04-09-2009, 03:55 PM	#17
Quension Senior Member Join Date: Feb 2009 Location: west coast USA Posts: 206	Originally posted by sajah @quension: the traffic light is the one which is composed of a lot of smaller red lamps, I'm not sure it correspond to old or new one in your term. Hm, I haven't seen that kind. It sounds like a newer LED type though. Glad you found where this effect is happening, even if not what's causing it.

04-09-2009, 04:23 PM	#18
my_photography Inactive Account Join Date: Feb 2009 Posts: 22	Interesting finding. Does the "llight" shows up very often or only under certain condition?

04-09-2009, 09:46 PM	#19
sajah Senior Member Join Date: Mar 2009 Location: South Korea Photos: Gallery Posts: 275 Original Poster	Originally posted by Quension Hm, I haven't seen that kind. It sounds like a newer LED type though. Glad you found where this effect is happening, even if not what's causing it. Yeah looks like a lot of LEDs. Originally posted by my_photography Interesting finding. Does the "llight" shows up very often or only under certain condition? It seems that it shows up all the time.. From all the pics I took yesterday at a traffic cross, the only reason I didnt always got the effect is because the red tail lights weren't always on, just when the drivers hit break pedal (I only tested during daylight)

04-13-2009, 02:56 PM	#20
AndrewG NY Veteran Member Join Date: Dec 2006 Location: Chappaqua, NY Photos: Gallery Posts: 688	Originally posted by sajah One more thing, when I open the image in photoshop, I notice that the red spots have almost white color in red channel and absolutely black in the green and red channel. Thoughts? Nice observation, but not at all surprising. I assume you meant black in green and blue channel. A bright full, even red like that would be pretty close to RGB(255, 0, 0).

04-13-2009, 11:20 PM	#21
sajah Senior Member Join Date: Mar 2009 Location: South Korea Photos: Gallery Posts: 275 Original Poster	Eh yea, my mistake

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