Frejoh466
Posts: 32
Joined: Sat Jun 29, 2013 5:09 pm

Camera way too dark?

Fri Sep 27, 2013 5:53 am

So I'm trying out the camera and on a bright day with lights on I get very dark pictures. With just the lamps on, the picture is almost entire black. With lamps and close to the window, I get a picture, but it's like a picture with a regular camera in a slightly too dark room.

I found "raspistill -ex night -br 85 -sh 100 -co 80 -q 100 -o /var/www/picture/`date +'%Y%m%d%H%M%S'`.jpg -w 1180 -h 860 -t 0" to get almost a normal picture, the "-ex night" does nothing by the way. And the pi has the latest updates from 13-09-03.

Anyone know if there is something I can do to fix this?

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
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Re: Camera way too dark?

Fri Sep 27, 2013 8:11 am

ednl wrote:"-t 0" might be the culprit. It means: take zero time to take the photo... First try it without any parameters except the output file name: "raspistill -o test.jpg" then go from there. Time setting of less than a second (one second is "-t 1000") will probably give bad results in low light.
That will be the problem. The camera needs to measure stuff over a few frames to get its exposure right. -t 0 doesn't give enough time for that to happen.
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Frejoh466
Posts: 32
Joined: Sat Jun 29, 2013 5:09 pm

Re: Camera way too dark?

Fri Sep 27, 2013 9:25 am

Ah, it's brighter. But I can't get the commands to work. "raspistill -ex night -br 75 -sh 100 -co 80 -q 40 -o /var/www/picture/test.jpg -w 1180 -h 860" gives me a good picture. (Remove "-ex night" and "-sh" does nothing)

Remove the,
"-br" and it's black, (obviously why)
"-co" and it's way to bright, (obviously why)
"-ex night" does nothing,
"-sh" does something, can't see differences but file is bigger. Might be sharper, but might also be a placebo.
"-br" "-co" and it's like normal, and too dark. (roughly 65% darker then if I would look with my eyes)
Remove all, and it's the same as "-br" "-co"

"-ex" is exposure, and ether I have no clue what "night" stand for, or it doesn't work.

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 26650
Joined: Sat Jul 30, 2011 7:41 pm

Re: Camera way too dark?

Fri Sep 27, 2013 9:52 am

Start with the basics,

How well does the following command work?

raspistill -o fred.jpg

EDIT: There is a very recent change to the code to fix sa problem with the -ex command (and will also fix other stuff). I think its has now made it to userland, so

sudo rpi-update

I think will get the latest version of the raspistill app with the fix in.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 26650
Joined: Sat Jul 30, 2011 7:41 pm

Re: Camera way too dark?

Fri Sep 27, 2013 10:05 am

Ah, apologies, the fix won't make it in until this weekend sometime.

In the mean time you can compile it yourself if you are desperate! But I'd suggest starting with minimal options and adding extra ones as you need them.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

Davinci
Posts: 10
Joined: Sun Jul 22, 2012 11:02 am

Re: Camera way too dark?

Sun Sep 29, 2013 5:06 pm

Does anyone know when the -ISO flag will be implemented on the raspvid command?

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 26650
Joined: Sat Jul 30, 2011 7:41 pm

Re: Camera way too dark?

Sun Sep 29, 2013 6:46 pm

Davinci wrote:Does anyone know when the -ISO flag will be implemented on the raspvid command?
It already is.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

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