Avoiding reflections...?

[JCDowdy]

Yes, it is fascinating. We've talked about floral iridescence from conical cells here and there in the forum. Bjørn has an interesting UV video of floral iridescence posted somewhere. It appears as though the flower is flashing signals in UV as the breeze moves it.

 

I was thinking a UV video while rotating an iridescent specimen might be interesting.

[cmoody]

If the iridescence is due to a diffraction type structure then you should use direct lighting not diffuse, the latter "Lambertian source" can result in no iridescence being visible.

 

But I want no iridescence, so I should use diffuse lighting :D

[Andrea B.]

Chris, I wonder if achieving a complete "no iridescence" is possible even with diffuse lighting?

You might instead have to present photographs of your iridescent specimen from multiple angles?

It is also possible that you could "stack out" the iridescence by layering photographs made from multiple angles using the Darker Color mode in Photoshop?

 

Please do let us know how your diffuse lighting is working out with regard to my first comment in this post. It would be very interesting to see a small example if you should get the time to post one.

[Shane]

But I want no iridescence, so I should use diffuse lighting

It can be difficult to completely eliminate diffraction induced iridescence even with diffuse lighting because most diffuse lighting setups still have some directionality to them. Peacocks still appear pretty spectacular even on very overcast days.

[cmoody]

 

Please do let us know how your diffuse lighting is working out with regard to my first comment in this post. It would be very interesting to see a small example if you should get the time to post one.

 

I will do my best. It's a bit frustrating that there is a blanket copyright enforcement on the images I am taking at the museum. The only specimens I can put on the internet are ones we've had donated to us, but we have a few glossy and iridescent ones...give me a few weeks and hopefully there might be some I can put up!

[JCDowdy]

But I want no iridescence..........

 

If the goal of your work is to document the collection then shouldn't the iridescence of iridescent specimens be documented?

[Andrea B.]

Cmoody wrote: ....blanket copyright enforcement on the images I am taking at the museum.

 

Understood, of course. I didn't mean to imply any 'pressure' - it is just my curiosity wanting to see how the UV looks. :D

 

You will have gained some very valuable experience with this work. Perhaps you can eventually write up a little summary of the work and any tips you might have?

 

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John wrote: If the goal of your work is to document the collection then shouldn't the iridescence of iridescent specimens be documented?

 

Agreed.