Small lines and bubbles in Photo, whats wrong?

[takafan]

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

 

[voxies09]

i guess, your lens' dust?

 

[cmeptb72]

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]

Nope, normal shorts no bubbles or the small white lines..

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

 

[cmeptb72]

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]

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]

The bubbles are definitely not hot pixels. I'm not sure what they are :sweat:

 

[Jer]

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

 

[driveanegg]

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 !!!

 

[takafan]

Thanks for the replies. I have tried the methods and it's starting to improve a little ~

 

[daredevil123]

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]

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]

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]

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.