A New Bare Bulb Flash Arrives

@Robs how does this influence the colour temperature?

mmmfotografie wrote in post #16904014
@Robs how does this influence the colour temperature?

I was asking you the question!!

Robsphoto wrote in post #16904129
I was asking you the question!!

For the stated aperture, the distance and power setting is of importance and that aperture was measured by me with a lightmeter. Using a lightmeter made it a lot easier for me to have well lit target at the first go. As stated before I was foremost interested in the Kelvin value.

So you don't have to read to much into that (distance) and it is more like a bonus.

If you use the colorchecker passport like it suppose to used (every light change and location) it won't make a difference on the color of the strobe output.

abbadon31 wrote in post #16904760
If you use the colorchecker passport like it suppose to used (every light change and location) it won't make a difference on the color of the strobe output.

I started the test because I first saw a Kelvin value of 7500 for the 180 degrees modifier and this could give problems when using more than one flash with different light modifiers.

If you want an accurate test your going to want to make sure everything around the colorchecker needs to to be neutral or your going to get a color cast. I see its on a wooden table top and that will cause color bounce.

If the colorcheck captures a even mixer of light from both strobes it going to give you the right balance. If one takes just from one source and add the other one in later with out a new capture the color will be off. When using a colorchecker one needs to always take a new picture of it when anything changes in lighting (power levels, distance or location change).

abbadon31 wrote in post #16906232
If you want an accurate test your going to want to make sure everything around the colorchecker needs to to be neutral or your going to get a color cast. I see its on a wooden table top and that will cause color bounce.

If the colorcheck captures a even mixer of light from both strobes it going to give you the right balance. If one takes just from one source and add the other one in later with out a new capture the color will be off. When using a colorchecker one needs to always take a new picture of it when anything changes in lighting (power levels, distance or location change).

That is why I taped colorchecker on a box so it would stick out in front of the wooden top.

I was not going for an 'real' Kelvin value. I would then need a neutral or absolute black surrounding and the Kelvin value measured by me should be lower when I look at the specifications stated by Godox. I just wanted to know the differences between the modifiers.

mmmfotografie wrote in post #16906288
That is why I taped colorchecker on a box so it would stick out in front of the wooden top.

I was not going for an 'real' Kelvin value. I would then need a neutral or absolute black surrounding and the Kelvin value measured by me should be lower when I look at the specifications stated by Godox. I just wanted to know the differences between the modifiers.

I get what your saying just making sure everyone else understands. The colorchecker i can see in the images is still to close to the wood. Example like green grass is at a subjects feet in an image, it will still pulls a color cast up past the subjects knees.

But what I see in the image is a not so black monitor and wood. Even the color off the not so black monitor is going to cause a color cast. If you want a true reading your going to want to setup a non reflective black or neutral white that covers the whole area of your light beam/path. If the beam spread is 15" then you need to cover around 18" and if your beam is 7' feet wide you need around 10' covered. (boxed)

I'm not attacking you on your testing or trying to start anything. All true testing need to be in controled environment. Like f/stop testing need to done in a pitch black room with no effective surfaces to get a true reading.

abbadon31 wrote in post #16906585
I get what your saying just making sure everyone else understands. The colorchecker i can see in the images is still to close to the wood. Example like green grass is at a subjects feet in an image, it will still pulls a color cast up past the subjects knees.

But what I see in the image is a not so black monitor and wood. Even the color off the not so black monitor is going to cause a color cast. If you want a true reading your going to want to setup a non reflective black or neutral white that covers the whole area of your light beam/path. If the beam spread is 15" then you need to cover around 18" and if your beam is 7' feet wide you need around 10' covered. (boxed)

I'm not attacking you on your testing or trying to start anything. All true testing need to be in controled environment. Like f/stop testing need to done in a pitch black room with no effective surfaces to get a true reading.

I have to check and clean the studio, sadly not mine, after today a group used it for making a video so I will run the test again with the same setup so I have a correction value to my earlier findings.

The studio is huge with a neutral white background+floor and 100% dark so ideal to test this. I can use the black cloth to even exclude any reflected light by the walls and floor.

Love these flashes
Yesterday's shoot sunny day in Paris
CL180 At full power in 22"BD, 5dmkii 85mm F2.5 50isos whith nd4

Beautiful shot and welcome to POTN!

Nice image grafikastudios. And welcome.

BamPhoto wrote in post #16907440
Beautiful shot and welcome to POTN!

thanks

SamFrench wrote in post #16907470
Nice image grafikastudios. And welcome.

thanks !!

This is a continuation on this topic by me: Colorchecker test different modifiers

I did more tests in the studio today when I was there and it was on black underground, black sides and a black background.

The colour temperatures are more stable and around 6400 Kelvin. This measured by a colorchecker and measured in RAW converter for Photoshop.

Bare bulb was 6050 Kelvin and in the more neutral setting it is 6450 Kelvin.
Standard reflector was 6350 Kelvin and in the more neutral setting it is 6400 Kelvin
180 Degrees modifier was 6950 Kelvin and in the more neutral setting it is 7300 Kelvin.

So the 180 degrees modifier that I got is probably this the first version with to much green in it and underneath you find two histograms.