Free Shipping on ALL Products
camera reviewsbest cameraslens reviewsphotography tipscamera forumvideo toursphotography bookssupport me
It is currently Fri Apr 18, 2014 9:28 am

All times are UTC




Post new topic Reply to topic  [ 9 posts ] 
Author Message
PostPosted: Sat Dec 31, 2011 4:37 am 
Offline

Joined: Fri May 27, 2011 4:10 pm
Posts: 398
Location: Ras Al Khaimah, UAE
I've noticed on my Canon 550D that if I'm doing long exposures, say 30 seconds, that they take AGES to save and was wondering why.

Just done a quick test and its taking about 30 seconds to save a 30 second exposure.

I have a fast-ish card in there (Scandisk Extreme 16Gb 30MB/s x10)

Anyone know whats going on?

_________________
Canon EOS 550D (with Magic Lantern)
18mm - 135mm Kit Lens, 50mm f1.8, Sigma 30mm f/1.4 EX DC HSM
430EX II Flash with Phottix Strato Wireless Tigger Set
Manfrotto 190CXPRO3 with 496 Ball Head. Gorilla Pod SLR
Canon Powershot A720IS with CHDK and intervalometer script. Pentax Optio W90

My Blog - http://www.ianganderton.wordpress.com


Top
 Profile  
 
 Post subject:
PostPosted: Sat Dec 31, 2011 9:03 am 
Offline

Joined: Mon Jan 18, 2010 3:52 pm
Posts: 2173
Location: The Netherlands
The camera substracts a Dark frame to reduce noise. Turn Long exp. noise red. off in the custom menu to disable it.

_________________
Ruben

Panasonic DMC-FZ18, Panasonic DMC-FZ28, Canon G5, Canon 350D, Canon 50D + BG-E2N
Tamron 17-50 2.8, Canon EF 70-200mm f/4L USM,
Canon 18-55 II plus lots of Minolta MD/M42 lenses and bodies


Top
 Profile  
 
 Post subject:
PostPosted: Sat Dec 31, 2011 9:37 am 
Offline

Joined: Fri May 27, 2011 4:10 pm
Posts: 398
Location: Ras Al Khaimah, UAE
Ahhhhh, cool, thanks Ruben, that info is much appreciated. I'll do a couple of trials to check the difference to see if the wait is worth it

_________________
Canon EOS 550D (with Magic Lantern)
18mm - 135mm Kit Lens, 50mm f1.8, Sigma 30mm f/1.4 EX DC HSM
430EX II Flash with Phottix Strato Wireless Tigger Set
Manfrotto 190CXPRO3 with 496 Ball Head. Gorilla Pod SLR
Canon Powershot A720IS with CHDK and intervalometer script. Pentax Optio W90

My Blog - http://www.ianganderton.wordpress.com


Top
 Profile  
 
 Post subject:
PostPosted: Sat Dec 31, 2011 1:09 pm 
Offline

Joined: Mon Jan 18, 2010 3:52 pm
Posts: 2173
Location: The Netherlands
Longer exposures with higher temperatures and higher ISOs, yes, there will surely be diffrences. But, 10 degrees/15 degrees, 100-200 ISO, no, it wont be that impressive the Dark frame substraction gives you.

_________________
Ruben

Panasonic DMC-FZ18, Panasonic DMC-FZ28, Canon G5, Canon 350D, Canon 50D + BG-E2N
Tamron 17-50 2.8, Canon EF 70-200mm f/4L USM,
Canon 18-55 II plus lots of Minolta MD/M42 lenses and bodies


Top
 Profile  
 
 Post subject:
PostPosted: Sat Dec 31, 2011 1:24 pm 
Offline

Joined: Fri May 27, 2011 4:10 pm
Posts: 398
Location: Ras Al Khaimah, UAE
Actually I read somewhere after googling 550d Long Exposure Noise Reduction following your answer that the noise reduction works best on lower ISO's and that with higher ISO's it can actually make it worse.

Here in the middle east if it gets below 20 deg its considered a bit chilly, its been down as low as 15 recently and everyone has been complaining bitterly!! Temperature induced noise and whether there is anything I can do about it is something I'd like to work out.

Here's the link re higher ISO's and increased noise with LENR http://www.imaging-resource.com/PRODS/T2I/T2IA5.HTM

Quote:
Long Exposure noise reduction can be performed for exposures one second or longer, and works by taking a second "dark frame" of equal duration with the shutter closed, and then subtracting it from the first frame. This reduces or eliminates most noise generated by the sensor during long exposures at low ISOs, but can make noise worse at higher ISOs (at ISO 1,600 and above)

_________________
Canon EOS 550D (with Magic Lantern)
18mm - 135mm Kit Lens, 50mm f1.8, Sigma 30mm f/1.4 EX DC HSM
430EX II Flash with Phottix Strato Wireless Tigger Set
Manfrotto 190CXPRO3 with 496 Ball Head. Gorilla Pod SLR
Canon Powershot A720IS with CHDK and intervalometer script. Pentax Optio W90

My Blog - http://www.ianganderton.wordpress.com


Top
 Profile  
 
 Post subject:
PostPosted: Sat Dec 31, 2011 2:02 pm 
Offline
User avatar

Joined: Thu Mar 27, 2008 6:48 am
Posts: 2879
Location: Nikonia California
Maybe because its taking a long exposure. You can't wait a minute for a photo??

_________________
WHO I AM BLOG, WHAT I DO BLOG
Facebook
*most of my photos nowadays come with a blog post. Please take some time and stop by :)


Top
 Profile  
 
 Post subject:
PostPosted: Sat Dec 31, 2011 2:07 pm 
Offline

Joined: Fri May 27, 2011 4:10 pm
Posts: 398
Location: Ras Al Khaimah, UAE
Palkaboy- ha ha, of course I can wait a mo. The query was because I was wondering why and it turns out there was a reason (on exposures longer than 1 second its actually taking 2 exposures!!) so the question was worth asking!!

_________________
Canon EOS 550D (with Magic Lantern)
18mm - 135mm Kit Lens, 50mm f1.8, Sigma 30mm f/1.4 EX DC HSM
430EX II Flash with Phottix Strato Wireless Tigger Set
Manfrotto 190CXPRO3 with 496 Ball Head. Gorilla Pod SLR
Canon Powershot A720IS with CHDK and intervalometer script. Pentax Optio W90

My Blog - http://www.ianganderton.wordpress.com


Top
 Profile  
 
 Post subject:
PostPosted: Sat Dec 31, 2011 3:29 pm 
Offline

Joined: Fri Sep 25, 2009 7:59 pm
Posts: 135
Location: west coast of Norway
one thing to remember would be to disable it if your doing extremely long exposures :P
i did a 17minute exposure with the 500D i had earlier, and it ended up taking another 17minute exposure for the noise reduction.
it ended up using probably 75% of the battery.

_________________
DeviantArt
Flickr
Canon 1D MK3, 5D MK3
Canon 50mm 1.4 USM, 100mm F2.8 USM, 70-200 F2.8 L IS II,
16-35 F2.8 L 24-105 L IS USM

Sigma 300mm F2.8

Canon Pixma PRO-9000 MKII

and a 17-40 F4L in a hundred little pieces


Top
 Profile  
 
 Post subject:
PostPosted: Sat Dec 31, 2011 3:52 pm 
Offline
User avatar

Joined: Sun May 25, 2008 12:48 pm
Posts: 7997
Location: UK
Generally I would turn it off, unless you're only doing "shorter" long exposures where it doesn't have much impact on shooting time. Hot pixels are usually handled quite well with modern raw converters anyway, and if needed for special applications (astrophotography) you could separately do a dark frame subtraction instead.

_________________
Canon DSLRs: 7D, 5D2, 1D, 600D, 450D full spectrum, 300D IR mod
Lenses: EF 35/2, 50/1.8, 85/1.8, 135/2+SF, 28-80 V, 70-300L, 100-400L, TS-E 24/3.5L, MP-E 65, EF-S 15-85 IS
3rd party: Zeiss 2/50 makro, Samyang 8mm fisheye, Sigma 150 macro, 120-300 f/2.8 OS, Celestron 1325/13
Tinies: Sony HX9V.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 9 posts ] 

All times are UTC


Who is online

Users browsing this forum: Bing [Bot], Yahoo [Bot] and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  

All words, images, videos and layout, copyright 2005-2012 Gordon Laing. May not be used without permission.
/ How we test / Best Cameras / Advertising / Camera reviews / Supporting Camera Labs

Webdesign by Alphabase IT
Powered by phpBB® Forum Software © phpBB Group