Something new and *very* useful for Einstein users ...

m.shalaby wrote in post #13659032
... it just seems like a lot of work for nothing. ...

Fine. But, Matthew, PLEASE explain how swapping a speedring insert is "a lot of work".

And speaking of 14" x 55" strips:

Mathew want to share a shot of the inside of your strip box with your reflector mod? I didn't think off doing that. This way will be much simpler if it works like you say.

m.shalaby wrote in post #13659592
...
Here is a shot of my Photoflex 14x55 used as a main light on subject with "my" mod in place:

Yes, we've seen these images many times already, Matthew. They really do not serve to prove your point because you do not offer a "control" group of images made with the same setup and the same modifiers but without your mod. The meter readings you cite are more meaningful.

You do realize, don't you, that a 6" metal disk placed 1.5' - 2.0" from the flashtube blocks more light than a strip of material on the back of the inner baffle. In fact, it blocks all direct light.

I really wish you wouldn't call me "dude". That moniker should be reserved for Jeff Lebowski.

Dave F.

tetrode wrote in post #13659329
Even without the deflector, it's apparent that the Kacey adapter has, for all practical purposes, killed the central hotspot so evident when a standard AB insert is used. So, yes, "my method" will indeed even out the hotspot.

Dave F.

That's a good test and the adapter appears to be doing exactly what I'd expect it to do. I'm impressed by this thread because there are several people that are really understanding even-coverage in practice. There's no way to test for it by lighting random "real-life" objects because there's no accounting for parallel planes and any light source can evenly cover a subject if placed at a far enough distance. The true test for the capability of a light source to provide even-coverage in practice is to see how balanced the light appears at the shortest distances possible from the subject while both planes are parallel to each other.

thanks man.

Ross J wrote in post #13661093
The true test for the capability of a light source to provide even-coverage in practice is to see how balanced the light appears at the shortest distances possible from the subject while both planes are parallel to each other.

?
How do you compare "bad" coverage vs. "good" coverage on a real subject w/ those conditions?
Or are we back to taking photos of the front of softboxes and walls again

Ross J wrote in post #13661093
The true test for the capability of a light source to provide even-coverage in practice is to see how balanced the light appears at the shortest distances possible from the subject while both planes are parallel to each other.

Actually the best way to measure the evenness of the light from a modifier is to take a flash meter reading with the meter directly against the fabric. You can see it done by a professional here to discuss the evenness of the light of the El Octa (skip to 2:25).

http://www.youtube.com​/watch?v=6yp9dzzZiM0

If you hold your meter further away from the surface of the fabric, it starts to "see" more of the front of the softbox and you lose the ability to meter the difference. This is especially true if you have the dome up because it "sees" in a 180 degree field of view and averages the result.

kenyee wrote in post #13661262
?
How do you compare "bad" coverage vs. "good" coverage on a real subject w/ those conditions?
Or are we back to taking photos of the front of softboxes and walls again

Lame as they are, a photo of the front of a softbox is at least a good visual representation of what the meter readings would tell you. By underexposing the image, you can easily see the differences in brightness across the diffusion fabric. Of course if you blow the image of your softbox out to pure white you can't see any differences at all.

Going back to your point about how much difference all this makes in terms of real image making.... not much. Even comparisons of totally different types of modifiers are nuanced, and ultimately a photo is judged on its content, not the softbox used. Of course we all like to have our tools be as effective as they can possibly be, right?

The one area I do see this making a difference in is specular highlights on skin. Your subject's skin will reflect your modifier back at the camera, giving you a faint representation of exactly what the front of your softbox looks like. Nice evenly lit softbox = nicer specular highlight on skin. Uneven softbox = uneven specular highlight.

Ross J wrote in post #13661093
That's a good test and the adapter appears to be doing exactly what I'd expect it to do. I'm impressed by this thread because there are several people that are really understanding even-coverage in practice. There's no way to test for it by lighting random "real-life" objects because there's no accounting for parallel planes and any light source can evenly cover a subject if placed at a far enough distance. The true test for the capability of a light source to provide even-coverage in practice is to see how balanced the light appears at the shortest distances possible from the subject while both planes are parallel to each other.

Sheldon N wrote in post #13661459
Actually the best way to measure the evenness of the light from a modifier is to take a flash meter reading with the meter directly against the fabric. You can see it done by a professional here to discuss the evenness of the light of the El Octa (skip to 2:25).

http://www.youtube.com​/watch?v=6yp9dzzZiM0

If you hold your meter further away from the surface of the fabric, it starts to "see" more of the front of the softbox and you lose the ability to meter the difference. This is especially true if you have the dome up because it "sees" in a 180 degree field of view and averages the result.

Lame as they are, a photo of the front of a softbox is at least a good visual representation of what the meter readings would tell you. By underexposing the image, you can easily see the differences in brightness across the diffusion fabric. Of course if you blow the image of your softbox out to pure white you can't see any differences at all.

Going back to your point about how much difference all this makes in terms of real image making.... not much. Even comparisons of totally different types of modifiers are nuanced, and ultimately a photo is judged on its content, not the softbox used. Of course we all like to have our tools be as effective as they can possibly be, right?

The one area I do see this making a difference in is specular highlights on skin. Your subject's skin will reflect your modifier back at the camera, giving you a faint representation of exactly what the front of your softbox looks like. Nice evenly lit softbox = nicer specular highlight on skin. Uneven softbox = uneven specular highlight.

agreed with you both!

m.shalaby wrote in post #13661201
Here are two shots

2nd: both inner and outer diffusion layer

IMG NOTICE: [NOT AN IMAGE URL, NOT RENDERED INLINE]

This is too much exposure to see the distribution. Anything exposed like this will look good. I'm not saying that your mod doesn't work, just that this image does not show that it does.

Sheldon N wrote in post #13661459
Lame as they are, a photo of the front of a softbox is at least a good visual representation of what the meter readings would tell you. By underexposing the image, you can easily see the differences in brightness across the diffusion fabric. Of course if you blow the image of your softbox out to pure white you can't see any differences at all.

No disagreement on how to measure evenness. I've done it myself w/ the Plume which many believe is one of the best softboxes ever made...and on which I found unevenness (the thinner profile is great though).
My comment was just that evenness (within some delta assuming it's not something ridiculous like 2 stops in spots) won't be noticeable in real photos...nowhere near the type/size of modifier you used for the photo.

Sheldon N wrote in post #13661459
The one area I do see this making a difference in is specular highlights on skin. Your subject's skin will reflect your modifier back at the camera, giving you a faint representation of exactly what the front of your softbox looks like. Nice evenly lit softbox = nicer specular highlight on skin. Uneven softbox = uneven specular highlight.

Up really close, I'd agree you might be able to see the difference, at least in theory
I'd still like to see a non-contrived A/B blind test comparison on real subjects...

So, I'm currently waiting for my Einsteins to arrive, I've ordered 6 PCB speedrings, but obviously now I'm questioning some things...

1) I've read a lot about the teeth/clamps (that hold the speed rings/softboxes to the actual strobe) not being able to fully lock onto certain types of speedrings (including older models from PCB) because of the depth of the actual ring itself...

(please be gentle, I'm very new to strobes/modifiers and studio lighting)

Will this new ring completely remedy this issue?

if so, is there any reason for me to keep my PCB ones at this price, and not order a few from Kacey if I get both; a full lock, AND this improved light distribution?
Cause to me, it doesn't sound like I want to keep my PCB speedrings at all!

-Thanks, Eddie!

Sheldon N wrote in post #13661459
The one area I do see this making a difference in is specular highlights on skin. Your subject's skin will reflect your modifier back at the camera, giving you a faint representation of exactly what the front of your softbox looks like. Nice evenly lit softbox = nicer specular highlight on skin. Uneven softbox = uneven specular highlight.

kenyee wrote in post #13662560
Up really close, I'd agree you might be able to see the difference, at least in theory
I'd still like to see a non-contrived A/B blind test comparison on real subjects...

I dont get it . Sheldon explained what you would be looking for.

Sheldon N wrote in post #13661459
Actually the best way to measure the evenness of the light from a modifier is to take a flash meter reading with the meter directly against the fabric. You can see it done by a professional here to discuss the evenness of the light of the El Octa (skip to 2:25).

I've always found it curious that people take these measurments with the meter right against the fabric. You are always going to have your model at least 1' away from the softbox, so it seems that it would be the only measurement that is relavant anyway.
Measuring the fabric makes as much sense as shoving your meter right inside the softbox against the tube itself, i.e. no sense at all.

DerekW wrote in post #13663250
I've always found it curious that people take these measurments with the meter right against the fabric. You are always going to have your model at least 1' away from the softbox, so it seems that it would be the only measurement that is relavant anyway.
Measuring the fabric makes as much sense as shoving your meter right inside the softbox against the tube itself, i.e. no sense at all.

For the purpose of measuring evenness of illumination from the front baffle of the softbox, it makes perfect sense. It's a totally different goal than metering light on your subject for the purposes of taking a picture. The farther away your meter is from the diffusion fabric the more you are metering the softbox as a whole rather than the actual evenness of the distribution of the light within the softbox.

It's totally different than measuring light on a subject, and is not comparable to sticking the meter on the flash tube at all.

We're not trying to measure the amount of light falling on a specific subject area, and this isn't about the angle of coverage coming out of the softbox. This is about getting a nice evenly illuminated softbox so that the softbox is more effective at wrapping the subject (a more evenly lit softbox is effectively a larger source) and so that the specular highlights refelecting off the subject are smooth and even.

I feared jumping into this, but here I go...
And I'm playing the devils advocate here, but really measuring the fabric for differences is really irrelevant if at normal working differences, the crossover from hot spot to edge makes little difference as it does blend together. I can see in a long strip box how it may come make some difference in a full body shot, but considering in most cases the softbox is feathered across the subject, what "real world" difference does it make?
I'm all for science and knowledge, but it does seem more like measuring for the sake of measuring.