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OREN
27th of May 2005 (Fri), 06:24
Hi.
Am in need of some expertise from anyone who has any advice regarding Aerial photography.

I'm sure its the same old question people have heard before...
How do I get rid of haze and other meteorological (including pollution) effects whilst shooting aerial photography?

Appreciate that weather, time of year and time of the day has to be taken into consideration, however am trying to grab any information I can on aerial film and filters that really work for true colour reproduction with good contrast, whilst loosing any effects of haze and the orange/red mask that I usually come back with.

-Are polarising filters the only answer?
-Infra red film..will this give me atmosphere-less (ie. no haze) images?
-Aerial negs...extended red senistivity with a blue mask for haze reduction?

Any advice will be greatly appreciated. Thank you.

Oren.

RbnDave
27th of May 2005 (Fri), 07:35
I cut and pasted this from a thread that was running last week. It should help you out.

Re: Airplane pics from the dust bin

--------------------------------------------------------------------------------

Chris,


Don't know how to save your pic. I never have any luck with air to air photos.

My trick for cityscapes is to sharpen way way more than I would for a normal pic. Before I do anything to the photo I run it though unsharp mask two to four times. The first time I set the levels to amount 150, radius 1.5, threshold 1.0. Those numbers are huge, but it works. I then sharpen it again at amount 20, radius 50, threshold 0. After that I may sharpen it one more time depending on how the pic looks. It is an art. Experiment. If you screw up just hit the undue button.

After sharpening, I crank up the contrast. I am extreme with the contrast too. I'll set the slider anywhere from +20 to +40. It all depends on the photo. Play with it a bit.

The last step is to play with the colors and levels. Most the pics I take out the window have a strange color cast and the levels are all wrong. I've found that most of my pics need the midtones and shadows darkened and the highlights lightened. This is also an art and totally depends on the photo. One of the strange things I've found is that I have to add a lot of red in either the midtones or shadows. If you can't figure out why your pic doesn't work try adding red. Same goes for reducing green. Sometimes taking out a little green makes a huge difference. As for the highlights, they are different. I find they need blue added to make things look natural. A lot of times the highlights will have a slightly red or green cast that needs to be removed.

If the picture has a lot of trees or water, use the magic wand tool to select the trees or water and then correct those colors seperately. I've found tree need lots of green added. Water is a nightmare. Good luck with that.

After doing all this, I will try auto levels. If you did things right, when you hit the auto levels comand only slight changes will be made. I find the auto levels smooths out the rough edges and makes the pic look more natural. Why not just hit auto levels to start with? Most of my pics from the air are so screwed up that auto levels doesn't have a clue what to do to fix things. Auto levels really doesn't help until you have your photo fixed manually.

Hope that helps.

Take your camera on every trip.

Dave

Chris,

Here's a before and after so you can see the massive amount of editting that goes into my cityscapes.

Before: http://www.pbase.com/rbndave/image/43483440
After: http://www.pbase.com/rbndave/image/36933356

I forgot the most important part. You have to start with a fixable photo. Make sure the sun is front or side lighting the buildings. Also, haze is the killer. If it's hazy don't even bother getting out your camera. I get my best pics in the morning and evenings shortly after cold frontal passage.

Another trick is to use your sunvisor to block out glare. On the CRJ our sunvisor is detachable. I take it off the slider and hold it under the camera at the base of the window to shield any out any reflections. Before I figured out this trick I had a bunch of pics with reflections of approach plates or glare from the latches on my flight bag. The sunvisor trick made this Chicago photo possible. http://www.pbase.com/rbndave/image/42048657

OREN
27th of May 2005 (Fri), 09:55
...Thanks ever so much for the past n' post, really appreciate your time.
Will certainly be trying out some of the post production suggestions.

Oren

mdmedicgod
27th of May 2005 (Fri), 15:22
Forget meteorlogical factors. First things first. What type of aicraft will these shot be taken from. I have tons of aerial photos some good and some with good teaching mistakes to show.

2nd what type of aerial photography.

Tom Reid
27th of May 2005 (Fri), 20:39
I fly a helicopter for a living. About 30% of my flights are spent with a photographer. We pick our days carefully. Nothing can be done about Mother Nature. Photoshop and lots of time may clean some photos up but you must pick your days for aerials else you'll be spending too much time in front of the puter. If anyone thinks otherwise please share. I'm always willing to learn, both in flying and photography!!

Pekka
28th of May 2005 (Sat), 05:25
For aerial shoot haze removal there is a special PS plugin in Realtexture Tools by CGSD, see http://www.cgsd.com/texture/tools.html . Very good.

The Dehaze Tool is only in Pro kit (expensive), but it might be worth it if you do lots of aerials. Better try the 10-day trial first. They might also sell it separately - mail them.

dentoman
29th of May 2005 (Sun), 20:52
Have you tried a UV filter?

Pyromaniac
29th of May 2005 (Sun), 23:01
We pick our days carefully. Nothing can be done about Mother Nature.

I have to agree with Tom. If you have alot of haze and othe atmoshperic conditions that are going to result in bad pic's do it another time. The day after it has rained is almost always a good day for aerial work. It clears the haze and polution from the air and after the front has moved through you will have relatively calm air with very mild turbulance.

The other thing that is important os the type of aircraft you'll be using. Generally a high wing Cessna is good for both air to ground and air to air.

embdude
30th of May 2005 (Mon), 01:34
Hi Oren,

First, what will you be shooting?

Air to ground:

Defined area subjects like Landmarks, real-estate etc...
Or
Broad vistas like mountains, islands, coastlines, etc...

Air to Air:

Aircraft, clouds, etc...

I have been shooting from airplanes since 1988, Some general advise...

1. Don't shoot through the aircraft windows. Open them, remove them or the door, or use a plane with special cutouts for photography.

Nowdays I fly in mostly airliners, and am forced to shoot through the windows. I have a hell of a time trying to get things right in post process. Dave's advice sure helped, but it is only a band-aid when often surgery will be required, Save yourself the trouble and dont shoot through the windows!

2. The more vertical the shot, the less the haze. This works great for surveying and real-estate type shots but wont for others...

3. Haze is reflected glare from air particles from sunlight. This reflection is different depending on the angle of the sun to you, it will change with the time of day, location of the particles, and your altitude. No haze at night! Not much arial photography either!!!

-Chris

Rendezvous
2nd of June 2005 (Thu), 02:43
You don't get haze at night, but you still get reduced visiblity.
The best days are the crystal clear crisp winter mornings you get in NZ. I can't really comment on other locations! My job is to fly the plane, not take the photos. But taking photos if fun too...

RbnDave
5th of June 2005 (Sun), 15:29
Check out this thread I started. Don't fight the haze. Work it.
http://photography-on-the.net/forum/showthread.php?p=585818#post585818