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Long Exposures

PostPosted: Sun Aug 21, 2011 4:36 pm
by skoker
I've had my Canon Rebel T2i for a while now and I love using it in conjuncture with the EOS utility, but I can never seem to get quality to be anywhere near what I would like it to be. The photos usually have so much noise its not funny.

Re: Long Exposures

PostPosted: Sun Aug 21, 2011 5:07 pm
by BigTruck
Make sure your ISO is at it's lowest setting.  The more ISO, the more noise.

Also, often times shots like the one you posted for an example are numerous exposures layered into one. 

Re: Long Exposures

PostPosted: Sun Aug 21, 2011 5:47 pm
by expat
Truck is right, a low ISO, down to around 50 if you can. The other thing is a very hight F stop otherwise the aircraft lights will burn the shot at the first pass. Really the only way to do a picture like this is patience and "BLF"

Matt

Re: Long Exposures

PostPosted: Sun Aug 21, 2011 8:14 pm
by BigTruck
I was going to mention fstop too but I wasn't positive, thanks Matt.

Re: Long Exposures

PostPosted: Sun Aug 21, 2011 8:40 pm
by skoker
I always leave my ISO at 100 and usually use F22 or so in my aperture, it still gives me lousy results. :-/

Re: Long Exposures

PostPosted: Sun Aug 21, 2011 11:05 pm
by f-35simpilot
Look at the settings I used for this night shot http://www.flickr.com/photos/hornethunt ... tostream... A few quick tips, do not underexpose, use the lowest iso possible as well as find the most sturdy surface possible (tripods are great but if it is windy it is useless)

Re: Long Exposures

PostPosted: Mon Aug 22, 2011 4:26 am
by expat
I always leave my ISO at 100 and usually use F22 or so in my aperture, it still gives me lousy results. :-/


What exposure times are you using. The example picture is in the region of 30 minutes maybe more judging by the star trails. Also are you using any filters? And I hate to ask ( :-[), but you are using a tri-pod

Re: Long Exposures

PostPosted: Mon Aug 22, 2011 11:28 am
by machineman9
A careful consideration with a small aperture... You will start to pick up the dirt from the lens and the sensor in your images.

In your camera you will have options for automatic noise reduction, and in Digital Photo Professional you'll also have a section to enable and control noise reduction. By the way, be sure to shoot in RAW format ONLY! You'll have so much more control over the images, which will make it far easier to post process and control exposure/noise reduction, etc.

Furthermore, you may be able to get away with a wider aperture if you buy a neutral density filter. They're basically filters that are just dark, and their main property is forcing your camera to prolonge the exposure. Your lens isn't the sharpest when it is at it's minimum aperture, they're usually sharpest about 2-3 stops down from their widest setting. DXOmark and personal testing should be able to provide you with graphs and results for the sharpest settings for each of your lenses.


But as mentioned, post some images!

Re: Long Exposures

PostPosted: Wed Aug 24, 2011 1:06 pm
by Mictheslik
Don't use any in camera noise reduction. Do it all in PP

Shoot RAW...more flexibility in terms of colour balance at night

To get the least noise possible I'd shoot a series of 30 second exposures rather than one that's 30 minutes long. Noise is created by the sensor heating up. If it's continuously processing data for 30 minutes it gets very hot.

Photos can easily be merged in freeware programs designed for star trails. :)

.mic