Light pollution

D

Daz9681

Messages
20
Name
Darran
Edit My Images
Yes
Been out and about testing my Sigma SD14, and playing with shutter speed priority to get motorway light trails.

Problem is with such long shutter speeds it picks up a lot of light pollution making the sky look yellow. Is there any way to get rid of this on camera rather than in PP as i'm not great with PP just yet.

Example:
SDIM6200.jpg


Thanks
:help:
 
Or shoot in RAW and play with WB.
 
Always shoot in RAW.

I dont know much about filters so no idea what an ND grad is, guessing grad means gradual or graduated
 
If you google using nd graduated filters. there are some very good tutorials. They mostley refer to using them in the day time. But the principals apply equaly well at night.
 
Last edited:
For me its a night shot you dont need a filter for a start, shoot in Bulb Mode,cable release on a tripod, F8/16 ISO100, focus manually maybe on the blue sign, take a shot about 30 secs see what you get,so you dont blow the head lights so much, then use that as a custom WB (that will reduce the LP) and adjust the shutter time to what you want to get out of the shot, what ever you do dont use a ND filter thats only going to prolong the length the shutters open, looking at that Id go for 30 to 90 secs
 
Last edited:
Shot was taken at 30 seconds. ISO100. On tripod.

Unsure what F it was but lens was a F2.8 :/ possible it was taken at F2.8 as i only set it on manual shutter speed not full manual.

Camera only has a 5 point AF and as i was using that it stuggled to focus until a passing car lit up part of the road.
 
Daz9681 said:
Shot was taken at 30 seconds. ISO100. On tripod.

Unsure what F it was but lens was a F2.8 :/ possible it was taken at F2.8 as i only set it on manual shutter speed not full manual.

Camera only has a 5 point AF and as i was using that it stuggled to focus until a passing car lit up part of the road.
Click to expand...

F2.8 is way to shallow DOF, F8 through to F22 is what you should use, prob thats why everything is OOF in your shot
 
Thanks everyone, pointers taken on board and i will get out again soon and post the results to see if i have improved
 
A lot of it has already been covered but basically the best time to shoot is between 15-45 minutes of sunset, this will give you some nice colours in the sky, and allow you to also pick up the nice movement in clouds (y)

Turn IS off and try and shoot at a minimum of f/8 I've actually found the optimum to be around f/16 for getting the most out of the red trails and the sky while stopping enough of the light from head lights to avoid really blowing out them...

Taking the light pollution out of the OP's image I would suggest a digital ND Grad if shot in raw with the white balance cooled down on the grad as if you take down the entire scene in white balance you'll start to get blue headlights, I'd also suggest that you've used far to much highlight reduction on that shot, finally it's rather soft from either camera shake or IS still being on would be my best guess?

Check out my signature for my guide on light trails, it may be of assistance to you (y)

Matt
MWHCVT
 
Just Dave said:
Matt Im surprised you say a grad thats one thing Ive never done, but if you say it works it probably does, (y)
Click to expand...

A digital grad works quite nicely it tends to be close to neutral on the exposure front doing it only really for the colour effect
 
Just Dave said:
Oh right you mean in PP not an actual grad on the lens
Click to expand...

Indeed mate, I've been known to use real NDG's in the past but you need to know exactly the right position/angle to be at to avoid nasty flare issues so would not recommend it to someone just starting out ;)
 
Went out and tried again with a bigger f number, as i'm still a total newbie it's a good learning curve for me.

this was f5.0 as i was still learning manual settings

482636_10152602216760387_1699556143_n.jpg


Once i'd sorted it out (that will teach me to be a man and not read a manual) the sun was almost down.

This is using f11
313359_10152602606615387_1121989500_n.jpg


But minimal light meant colour of the tree's is lost :(


But thanks for all the advice
 
Have to admit that I prefer the last one Darran. The loss of detail in the trees (to me) removes a conflicting area of interest, leaving just the light trails
 
Second one for me too Darran. In the first one the sky is too much like daylight. You could even go a bit darker (ie later) with the sky in the second shot. Btw you need to sort the chromatic aberration out, at least in the first one (the purple fringing near the tree branches)
JohnyT
 
Last edited:
Thanks guys.

Johnny i have no idea what that is or how to remove it
 
Another tip that i like to try with traffic trails is to shoot in bulb mode, and have a piece of matt black card with me. If at any time during the exposure the traffic quiets, place the black card in front of the lens without touching it. Remove the card whenevr more cars are coming. This should cut down on a lot of the unnecessary light pollution
 
You must log in or register to reply here.
Back
Top