Canon Digital Photography Forums  

Go Back   Canon Digital Photography Forums > 'Equipment Talk' section > Small Flash and Studio Lighting
Register Rules FAQ Members List Search Today's Posts Mark Forums Read



Reply
 
Thread Tools Display Modes
Old 8th of August 2012 (Wed)   #1
North Dude
Member
 
North Dude's Avatar
 
Join Date: Nov 2010
Location: QC, Canada
Posts: 319
Question please help me with my L-358

Hi all,

I have a sekonic L-358, and read the manual many times. Exposure compensation on the meter is set to 0, and calibration is also at 0. I'm using it in Auto-reset cordless flash mode, I'm setting iso at 200, shutter at 1/200 and adjusting my strobes to get f8.0. I'm using the meter with the lumisphere out and pointed towards the lens. After adjusting the strobes and once I get the correct value, I fire the strobes a couple of times to make sure I have a constant exposure, I get 8.0 each time. But when I shoot the image with my camera in manual mode set at iso 200, 1/200 and f8.0 I seem to get an underexposed image. Here are two tests images, the first one is at f8.0 and the second one is at f5.6, (without changing the power or position of the strobes) I created the jpg files in LR3.6, the only thing I changed is that I used the camera standard profile and enabled the lens correction. I did not touch any of the exposure parameters. When I chimp, I also notice that the histogram seem to indicate underexposure. I shot this with my 70-200, I also tried with my 18-135 and got the same results.

Am I doing something wrong here? What do I don't understand?
Attached Images
File Type: jpg iso200f8.0.jpg (104.5 KB, 142 views)
File Type: jpg iso200f5.6.jpg (117.5 KB, 142 views)
__________________
7D | Σ 70-200 2.8 OS | Σ 10-20 4-5.6 | Σ 17-50 2.8 OS | Σ 50 1.4 | Σ 1.4x | Extension tubes | 580 EX II | Some lights / triggers | Manfrotto 055XPROB / 498RC2
North Dude is online now   Reply With Quote
This ad block will go away when you log in as member
Old 8th of August 2012 (Wed)   #2
s2kennyc
Member
 
s2kennyc's Avatar
 
Join Date: Aug 2009
Location: Sourthern CA
Posts: 790
Default Re: please help me with my L-358

When you say strobes...I'm assuming you mean more than 1?

If so, just for testing purposes, can you just use 1 strobe and see if you can get a correct exposure with one? Just want to eliminate some variables here.
__________________
"I'm a pixel peeper...there, I said it!"

-Ken
flickr | Gear List
s2kennyc is offline   Reply With Quote
Old 8th of August 2012 (Wed)   #3
North Dude
Member
 
North Dude's Avatar
 
Join Date: Nov 2010
Location: QC, Canada
Posts: 319
Default Re: please help me with my L-358

I'm using two strobes.
__________________
7D | Σ 70-200 2.8 OS | Σ 10-20 4-5.6 | Σ 17-50 2.8 OS | Σ 50 1.4 | Σ 1.4x | Extension tubes | 580 EX II | Some lights / triggers | Manfrotto 055XPROB / 498RC2
North Dude is online now   Reply With Quote
This ad block will go away when you log in as member
Old 8th of August 2012 (Wed)   #4
Bob_A
Cream of the Crop
 
Bob_A's Avatar
 
Join Date: Jan 2005
Location: Alberta, Canada
Posts: 7,960
Default Re: please help me with my L-358

Hi Ian.

Sounds to me like you're using the correct approach.

Without being there it's pretty hard to tell if the first image is under-exposed or if the second image is over-exposed Any chance you could repeat the shot with a grey card and white card framing the stuffed animal?

Also try what Ken suggested. Starting simple can help get to the bottom of things.
__________________
Bob

Bob_A is offline   Reply With Quote
Old 8th of August 2012 (Wed)   #5
North Dude
Member
 
North Dude's Avatar
 
Join Date: Nov 2010
Location: QC, Canada
Posts: 319
Default Re: please help me with my L-358

Quote:
Originally Posted by imorisse View Post
I'm using two strobes.
And my 580 for hair light. (in manual mode)

The first tests I did, I did not have the 580, but I got the same results. I did not try it with only on strobe.
__________________
7D | Σ 70-200 2.8 OS | Σ 10-20 4-5.6 | Σ 17-50 2.8 OS | Σ 50 1.4 | Σ 1.4x | Extension tubes | 580 EX II | Some lights / triggers | Manfrotto 055XPROB / 498RC2
North Dude is online now   Reply With Quote
Old 8th of August 2012 (Wed)   #6
North Dude
Member
 
North Dude's Avatar
 
Join Date: Nov 2010
Location: QC, Canada
Posts: 319
Default Re: please help me with my L-358

Quote:
Originally Posted by Bob_A View Post
Hi Ian.

Sounds to me like you're using the correct approach.

Without being there it's pretty hard to tell if the first image is under-exposed or if the second image is over-exposed Any chance you could repeat the shot with a grey card and white card framing the stuffed animal?

Also try what Ken suggested. Starting simple can help get to the bottom of things.
Here is a test shot with a grey card and a piece of white cardboard...
Attached Images
File Type: jpg facebook-2645.jpg (125.7 KB, 133 views)
__________________
7D | Σ 70-200 2.8 OS | Σ 10-20 4-5.6 | Σ 17-50 2.8 OS | Σ 50 1.4 | Σ 1.4x | Extension tubes | 580 EX II | Some lights / triggers | Manfrotto 055XPROB / 498RC2
North Dude is online now   Reply With Quote
Old 8th of August 2012 (Wed)   #7
s2kennyc
Member
 
s2kennyc's Avatar
 
Join Date: Aug 2009
Location: Sourthern CA
Posts: 790
Default Re: please help me with my L-358

Try it with one strobe first to make sure that your meter is functioning correctly. Post up the result so that we can see that.
__________________
"I'm a pixel peeper...there, I said it!"

-Ken
flickr | Gear List
s2kennyc is offline   Reply With Quote
Old 8th of August 2012 (Wed)   #8
Bob_A
Cream of the Crop
 
Bob_A's Avatar
 
Join Date: Jan 2005
Location: Alberta, Canada
Posts: 7,960
Default Re: please help me with my L-358

Quote:
Originally Posted by imorisse View Post
Here is a test shot with a grey card and a piece of white cardboard...
When I look at the image in ACR it appears to be 1/2 to 3/4 stop under-exposed. Here it is bumped up by 0.75 so that the whites just start to clip:
Attached Images
File Type: jpg facebook-2645.jpg (149.7 KB, 127 views)
__________________
Bob


Last edited by Bob_A : 8th of August 2012 (Wed) at 21:14.
Bob_A is offline   Reply With Quote
Old 8th of August 2012 (Wed)   #9
Bob_A
Cream of the Crop
 
Bob_A's Avatar
 
Join Date: Jan 2005
Location: Alberta, Canada
Posts: 7,960
Default Re: please help me with my L-358

Ian, does the L-358 have an ISO 2 setting that can be used for "filter compensation"? If it does, and you have it set up that way, is it set to zero? My L-558R has that feature.
__________________
Bob

Bob_A is offline   Reply With Quote
Old 8th of August 2012 (Wed)   #10
110yd
Member
 
Join Date: Jan 2005
Posts: 590
Default Re: please help me with my L-358

How are you triggering your strobes? If you are using a wireless trigger to fire your strobes, is there any chance that you are not firing the strobes at the right time? I recently had a situation where I set up two lights with a trigger, and used another trigger to fire the camera. Everything worked fine on day one. On day two I set the equipment up, but I managed to get the TX units swapped. The photos were under exposed, and I was stumped for a minute. Eventually I figured out that the transmitters for the triggers got swapped.....The lights were firing, but they were not synchronized with the shutter on the camera.

Hope this helps,

110yd
110yd is offline   Reply With Quote
Old 8th of August 2012 (Wed)   #11
Ron McQueen
Junior Member
 
Join Date: Dec 2010
Posts: 23
Default Re: please help me with my L-358

You may also be doing nothing wong. Your 358 and 7d may not be with the same calabration zone. if you caint find any thing wong try seting up 1/2 to 2/3rd hotter than you want to shoot. York it from there untill you find the spot that it maches up. you can test this with a friends 358shooting side by side and see if they match.
Ron McQueen is offline   Reply With Quote
Old 9th of August 2012 (Thu)   #12
North Dude
Member
 
North Dude's Avatar
 
Join Date: Nov 2010
Location: QC, Canada
Posts: 319
Default Re: please help me with my L-358

Quote:
Originally Posted by Bob_A View Post
Ian, does the L-358 have an ISO 2 setting that can be used for "filter compensation"? If it does, and you have it set up that way, is it set to zero? My L-558R has that feature.
Yes there is an iso 2 setting, but the way I understand it, is when I press the iso2 button after my measurment, I shows me the equivalent fstop with that iso.
__________________
7D | Σ 70-200 2.8 OS | Σ 10-20 4-5.6 | Σ 17-50 2.8 OS | Σ 50 1.4 | Σ 1.4x | Extension tubes | 580 EX II | Some lights / triggers | Manfrotto 055XPROB / 498RC2
North Dude is online now   Reply With Quote
Old 9th of August 2012 (Thu)   #13
North Dude
Member
 
North Dude's Avatar
 
Join Date: Nov 2010
Location: QC, Canada
Posts: 319
Default Re: please help me with my L-358

Quote:
Originally Posted by 110yd View Post
How are you triggering your strobes? If you are using a wireless trigger to fire your strobes, is there any chance that you are not firing the strobes at the right time? I recently had a situation where I set up two lights with a trigger, and used another trigger to fire the camera. Everything worked fine on day one. On day two I set the equipment up, but I managed to get the TX units swapped. The photos were under exposed, and I was stumped for a minute. Eventually I figured out that the transmitters for the triggers got swapped.....The lights were firing, but they were not synchronized with the shutter on the camera.

Hope this helps,

110yd
I'm using FR603's to sync, but I aslo tried connecting a sync cable to my meter and having my other strobe on optical slave, I got the same results...
__________________
7D | Σ 70-200 2.8 OS | Σ 10-20 4-5.6 | Σ 17-50 2.8 OS | Σ 50 1.4 | Σ 1.4x | Extension tubes | 580 EX II | Some lights / triggers | Manfrotto 055XPROB / 498RC2
North Dude is online now   Reply With Quote
Old 9th of August 2012 (Thu)   #14
North Dude
Member
 
North Dude's Avatar
 
Join Date: Nov 2010
Location: QC, Canada
Posts: 319
Default Re: please help me with my L-358

Quote:
Originally Posted by s2kennyc View Post
Try it with one strobe first to make sure that your meter is functioning correctly. Post up the result so that we can see that.
Ok, I"ll try this tonight
__________________
7D | Σ 70-200 2.8 OS | Σ 10-20 4-5.6 | Σ 17-50 2.8 OS | Σ 50 1.4 | Σ 1.4x | Extension tubes | 580 EX II | Some lights / triggers | Manfrotto 055XPROB / 498RC2
North Dude is online now   Reply With Quote
Old 9th of August 2012 (Thu)   #15
North Dude
Member
 
North Dude's Avatar
 
Join Date: Nov 2010
Location: QC, Canada
Posts: 319
Default Re: please help me with my L-358

Quote:
Originally Posted by Ron McQueen View Post
You may also be doing nothing wong. Your 358 and 7d may not be with the same calabration zone. if you caint find any thing wong try seting up 1/2 to 2/3rd hotter than you want to shoot. York it from there untill you find the spot that it maches up. you can test this with a friends 358shooting side by side and see if they match.
This is what I think I have to do, I was just wondering if it was normal...
__________________
7D | Σ 70-200 2.8 OS | Σ 10-20 4-5.6 | Σ 17-50 2.8 OS | Σ 50 1.4 | Σ 1.4x | Extension tubes | 580 EX II | Some lights / triggers | Manfrotto 055XPROB / 498RC2
North Dude is online now   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 19:36.


Powered by vBulletin® Version 3.6.12
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
This forum is not affiliated with Canon in any way and is run as a free user helpsite by Pekka Saarinen, Helsinki Finland. You will need to register in order to be able to post messages. Cookies are required for registering and posting. HTML in messages is not allowed, plain website addresses are automatically made active by the board.