Tutorial for Sekonic L-758DR: How to create a custom profile

Hi Curt,

Creating the profile for Ambient light is done exactly the same way and does need to be done with controlled lighting. We naturally think of going outdoors to use natural ambient light but that is not the correct method. If you use the same setup as you used for strobes but just used the modeling lights on full power and obviously much closer you should be fine. But you can use any form of artificial ambient light that does not change.

Regarding the settings for Ambient profiling. Just as you determined that, for example, f/8 was your standard exposure before, you would set up so your starting settings are f/8 and 1/30 second (1/30 is recommended by Sekonic. I don't know why this value is used). Then you take the subsequent shots by increasing and decreasing the shutter speed and end up with frames shot at 1/4, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, always adjusting for f/8.

TMR Design wrote in post #5039788
Hi Curt,

Creating the profile for Ambient light is done exactly the same way and does need to be done with controlled lighting. We naturally think of going outdoors to use natural ambient light but that is not the correct method. If you use the same setup as you used for strobes but just used the modeling lights on full power and obviously much closer you should be fine. But you can use any form of artificial ambient light that does not change.

Regarding the settings for Ambient profiling. Just as you determined that, for example, f/8 was your standard exposure before, you would set up so your starting settings are f/8 and 1/30 second (1/30 is recommended by Sekonic. I don't know why this value is used). Then you take the subsequent shots by increasing and decreasing the shutter speed and end up with frames shot at 1/4, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, always adjusting for f/8.

Thanks for all your help. I think have almost everything. I'm going to use two halogen lamps I have for my modeling lights (I had to look that up. Nothing like a little learning) on each side of the target at 45 degress. I take it I would then set the Sekonic to F8 and then move the lights to get 1/60 shutter speed? Do I set the camera to the same value or whatever shutter speed that centers the meter. For the other shutter speeds, when you say aways adjusting, I got lost. For each exposure, I was planning on leaving the camera at F8 and adjusting the shutter speed as you specified. What else would I adjust? I would think you would leave everything else constant so you would get When I change ISO, I would go back to F8 and move the lights to get 1/60 again.

I actually used my Sekonic for its real purpose today. I took a number to readings off various light and dark area in my landscape scene and pushed the AVE. to get my shutter speed. It's a lot easier than just using the camera when you shoot Manual mode.

Curt

Stoffer T4105C transmission wedge

Received the Stoffer T4105C transmission wedge. Now to follow your tutorial. For anyone trying this method of calibration, instructions on how to photograph the wedge are here:
http://www.imatest.com​/docs/q13.html (lightbox near the bottom of the page)
and here:
http://forums.dpreview​.com …rum=1022&messag​e=27000481

-jts

Hi jts,

Are you doing the profile with the old version 1 software or the new version 2?

TMR Design wrote in post #5141888
Hi jts,

Are you doing the profile with the old version 1 software or the new version 2?

I saw your mention of a 2.0 version of the software so I downloaded it. The documentation is improved and it looks like entering data will be a log easier.

Question: Would it be better to set the camera (D3 in my case) to save tiff files or run them through Photoshop without any adjustments? I always do raw so I don't know how or if it's possible to turn off all the in camera adjustments/post processing for tiff output.

Curt

cortes wrote in post #5150321
I saw your mention of a 2.0 version of the software so I downloaded it. The documentation is improved and it looks like entering data will be a log easier.

Question: Would it be better to set the camera (D3 in my case) to save tiff files or run them through Photoshop without any adjustments? I always do raw so I don't know how or if it's possible to turn off all the in camera adjustments/post processing for tiff output.

Curt

I found out the hard way that the Data Transfer software wants the profile settings in full stops and tenths, not half or third. Be sure to set your 758 accordingly. I suppose there may be a way to translate them, but I'm not aware of it so I'm going back for my fifth or sixth shooting. I keep messing up one step of another.

cortes wrote in post #5150321
I saw your mention of a 2.0 version of the software so I downloaded it. The documentation is improved and it looks like entering data will be a log easier.

Question: Would it be better to set the camera (D3 in my case) to save tiff files or run them through Photoshop without any adjustments? I always do raw so I don't know how or if it's possible to turn off all the in camera adjustments/post processing for tiff output.

Curt

Hi Curt,

No reason to shoot those massive TIFF files. You can shoot RAW and technically you can shoot JPG as long as you set it to be completely neutral, no NR, no D-Lighting, zip.

I always did the previous profiling with RAW files that were then converted to JPG in Photoshop.

In checking out Version 2 I say that when you select images you can only select JPG which means that ultimately that's what you want to end up with so the software can use the images.

cortes wrote in post #5150505
I found out the hard way that the Data Transfer software wants the profile settings in full stops and tenths, not half or third. Be sure to set your 758 accordingly. I suppose there may be a way to translate them, but I'm not aware of it so I'm going back for my fifth or sixth shooting. I keep messing up one step of another.

The software is based on the same concept as version 1. Working with whole stops is nothing new but there's not reason to change your meter. You take your test shot(s) accordingly so that you're shooting whole stops.

TMR Design wrote in post #5150534
The software is based on the same concept as version 1. Working with whole stops is nothing new but there's not reason to change your meter. You take your test shot(s) accordingly so that you're shooting whole stops.

I never made it through the first version so I don't know how it worked. I had to change the meter option 3 to be whole stops as I usually use thirds.

cortes wrote in post #5150800
I never made it through the first version so I don't know how it worked. I had to change the meter option 3 to be whole stops as I usually use thirds.

OK unless I am missing something I don't believe you have to change your meter at all. You can take all the necessary and do your metering without making that change?

Can you tell me why you believe you have to do that?

TMR Design wrote in post #5150864
OK unless I am missing something I don't believe you have to change your meter at all. You can take all the necessary and do your metering without making that change?

Can you tell me why you believe you have to do that?

When I go to the Measure Value step in the profile wizard advanced mode where you enter the shutter speed, aperture, and tenths the given aperture values are whole stops.

I was setting the lighting to give an incident reading of 1/30, f/5.6, and some tenths. When I did the reflected reading, I would some times get f/6.7 as the value. The software doesn't have f/6.7 as a value. Is there an option somewhere I'm missing or am I doing this all wrong.

Curt

Sorry Curt. I think you're missing something or overcomplicating this. There is nothing about this procedure that you can not do with your meter set as it was. Just because it is reading 1/3 stops or 1/10's of stops doesn't interfere or hamper your ability to take meter readings, fine tune your lights for the appropriate readings and use those results.

TMR Design wrote in post #5152642
Sorry Curt. I think you're missing something or overcomplicating this. There is nothing about this procedure that you can not do with your meter set as it was. Just because it is reading 1/3 stops or 1/10's of stops doesn't interfere or hamper your ability to take meter readings, fine tune your lights for the appropriate readings and use those results.

Robert you may be right. If my meter reading was 30s, f/6.7, and some odd seconds what value would I enter? When I follow the steps below the possible values in the range of f/6.7 are 4.0, 5.6, 8.0, 11. I can't select 6.7. I can adjust the lights to give a full stop reading in Incident, but reflected reading is sometimes off by a half stop when you don't take the tenths into account. Would f/6.7 and 0/10's just be f/5.6 and 5/10's?

Open Data Transfer Software 2.0
Click Create New Profile
Click Advanced Mode
Select Exposure Profile Target and click Next
Select Ambient and click Next
Select ISO Sensitivity
Select Incident Shutter Speed, Aperture, and 1/10 using the values that I took with the meter in Incident mode
Select Reflected Shutter Speed, Aperture, and 1/10 using the values that I took with the meter in Reflected mode

Hi Curt,

Are you trying to input the values for Ambient Reflected?

Sekonic recommends using 1/30 as the base shutter speed. In setting up the lights the idea is to position and distance them from the card so you get the desired meter reading. The software wants to work with whole stops so you obviously don't want readings that are anything other than full stops. This means you need to move your lights, whether closer of further away, to get the full stop reading.

Unless I've misunderstood the conditions you've outlined it sounds like you just need to move your lights.

One thing I would like to clarify from your last post. You indicate you got a meter reading of f/6.7. Without sounding cocky... are you sure you are displaying f-stops and not EV value? If it's set to f-stops then you would see full, half or third stops, followed by a decimal value, whereas if you're displaying EV then 6.7 is really f/8 + .7

Please check the mode you are using.

I should correct myself.

If you're displaying 1/2 stops you could be seeing f/6.7 but I didn't think you were.