Small lines and bubbles in Photo, whats wrong?


Status
Not open for further replies.

takafan

Senior Member
Nov 26, 2008
1,000
6
38
Bedok
#1
As below in the pic. Anyone has any idea?


Settings was 85s, f13. There are 2 fine white lines, and bubbles. I'm sure there were no stars when i took the shot, so the 2 lines couldn't be stars.



This was taken about 5mins earlier:
Settings were 70s, f13



Please enlighten me :)
 

Last edited:

cmeptb72

New Member
Nov 25, 2006
379
0
0
West
#3
The lines are likely to be hot pixels. This happens when the sensor heats up due to long exposure.

Do you have the same problem when taking shots as normal shutter speeds?
 

takafan

Senior Member
Nov 26, 2008
1,000
6
38
Bedok
#4
Nope, normal shorts no bubbles or the small white lines..

Just that i was trying long exposure, then it happened.
 

cmeptb72

New Member
Nov 25, 2006
379
0
0
West
#5
Hmm. It's hot pixels then - I've got the same problem with my 40D when taking long exposures too.

Guess the alternative solution is to clone out the affected area.:)
 

takafan

Senior Member
Nov 26, 2008
1,000
6
38
Bedok
#6
Hmm. It's hot pixels then - I've got the same problem with my 40D when taking long exposures too.

Guess the alternative solution is to clone out the affected area.:)
Even those big big bubbles are hot pixels ????
 

cmeptb72

New Member
Nov 25, 2006
379
0
0
West
#7
The bubbles are definitely not hot pixels. I'm not sure what they are :sweat:
 

Jer

New Member
Aug 26, 2003
807
0
0
West
jer6263.multiply.com
#8
The big bubbles could be dust on the sensor and they show up since u are shooting at f13. Try shooting against a white background using f13 or f16 and see if the same spots appear
 

Sep 8, 2009
615
0
0
Choa Chu Kang
#9
Big bubbles are dust, most prob on sensor
The dust are in the same spot on both pictures ...

Small white lines are light trails from stars - though they may not be obvious on taking the picture, long exposure will pick out tiny bits of light .... ;)

Hope that helps !!!
Keep shooting !!! :D
 

takafan

Senior Member
Nov 26, 2008
1,000
6
38
Bedok
#10
Thanks for the replies. I have tried the methods and it's starting to improve a little ~
 

daredevil123

Moderator
Staff member
Oct 25, 2005
21,636
59
48
lil red dot
#11
The white bright lines are stars la. and they move in the sky slowly because the earth is turning. So when taking long exposure, they look like lines.

The "bubbles" can be many things. Dust on lens or sensor or filter, stains on the lens/filter. It could also be condensation, or water drops. Clean your lens, filters and blow your sensor. Check again at small aperture F29 or something shooting a whilte wall.
 

takafan

Senior Member
Nov 26, 2008
1,000
6
38
Bedok
#12
The white bright lines are stars la. and they move in the sky slowly because the earth is turning. So when taking long exposure, they look like lines.

The "bubbles" can be many things. Dust on lens or sensor or filter, stains on the lens/filter. It could also be condensation, or water drops. Clean your lens, filters and blow your sensor. Check again at small aperture F29 or something shooting a whilte wall.
Thanks a lot for the advice. I will do another thorough cleaning and checking :thumbsup:

But the thing is that, i shot at lower exposure timings, there were no bubbles...
 

agentxq49

New Member
Jun 1, 2009
505
0
0
Sembawang
#13
Thanks a lot for the advice. I will do another thorough cleaning and checking :thumbsup:

But the thing is that, i shot at lower exposure timings, there were no bubbles...
at long exposure, esp with small apertures, more things are in focus. when using a large aperture, the DOF is thinner, thus the dust is more out of focus in a sense, and thus goes invisible.
 

daredevil123

Moderator
Staff member
Oct 25, 2005
21,636
59
48
lil red dot
#14
Thanks a lot for the advice. I will do another thorough cleaning and checking :thumbsup:

But the thing is that, i shot at lower exposure timings, there were no bubbles...
Of course. diffract some light, thats how you see them. The light is weak, so if the ambient light is bright, you won't see it. The aperture is big, you won't see it either.
 

Status
Not open for further replies.