Argynnis paphia

Images taken in a controlled environment or with a posed subject. All subject types.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

Gérard-64
Posts: 256
Joined: Mon Jun 02, 2008 7:16 am
Location: Pyrénées atlantiques-France
Contact:

Argynnis paphia

Post by Gérard-64 »

Image

Stacked with Zerene.

rjlittlefield
Site Admin
Posts: 23561
Joined: Tue Aug 01, 2006 8:34 am
Location: Richland, Washington State, USA
Contact:

Post by rjlittlefield »

Argynnis paphia -- one of the Fritillary butterflies -- very nice.

This image seems to have a strong blue cast. The natural color of these butterflies is usually rich orange, with the lighter parts being more neutral gray. But in this image the orange seems muted, and the palps and light-colored scales around the eyes are tinged in blue. How did you illuminate this and set the color balance?

--Rik

Gérard-64
Posts: 256
Joined: Mon Jun 02, 2008 7:16 am
Location: Pyrénées atlantiques-France
Contact:

Post by Gérard-64 »

Rik,the background was a black cardboard,color balance was on Auto,light from the sun,the insect was covered by a plexiglass tunnel.See enclosed image.
Image

I think that the strong blue cast is due to the reflexion of the sky in the windows..

rjlittlefield
Site Admin
Posts: 23561
Joined: Tue Aug 01, 2006 8:34 am
Location: Richland, Washington State, USA
Contact:

Post by rjlittlefield »

Gérard,

Thanks for the follow-up image showing your setup. It's both helpful about the color and very interesting by itself.

From this pair of images, it's clear that the closeup is much too blue.

In the image of your setup, the black cardboard has only a slight blue cast. Using Photoshop to sample a spot in front of the camera, I see RGB values of 42,53,59.

But in the closeup, a sample of the background is RGB = 10,31,76. Much less red, some less green, and even more blue.

I have never seen this much blue cast caused by just being in shade, illuminated by blue sky and reflections from the surroundings. It looks more like what happens when I accidentally set white balance on incandescent and then shoot daylight or flash. (I am embarrassed to admit how often I do this.)

So I am thinking that either AWB on your camera did something very odd, or that perhaps the camera was actually set for incandescent and not auto.

In any case, I recommend to use custom color balance whenever there is question about the lighting. What I do is to set up the specimen and lighting, then temporarily set the camera to auto exposure, hold a white index card in front of the specimen, and take one picture. The auto exposure meters the white card as if it were gray, so the image comes out gray with some color cast. Then I set custom color balance from that image. This removes the color cast from later images shot with the same lighting. Of course I also have to remember to set the camera to actually use the custom white balance. Another mistake that I make all too often is to go through the process of calibrating a custom white balance, and then leave the camera set on something else like incandescent!

Switching subjects, I am interested in your setup. It appears to me that you have created a homemade screw-driven focus slide from wood and clamps. Is this correct? If so, it is a thing of beauty! Can you tell us a little more about how it is built and how it works?

I also notice on the wall, just above your monitor, what appears to be a stereo pair of some green object -- your avatar, perhaps? If you like stereo, then I suggest playing around with the synthetic stereo capabilities in Zerene Stacker. Of course I'm biased because I wrote the thing, but quite frankly I've been surprised by how well it works and I've been having great fun re-processing old stacks into stereo pairs. See HERE for examples. The added sense of depth is very enlightening in some cases.

Hope this helps!

--Rik

Wayne Baker
Posts: 47
Joined: Wed Nov 26, 2008 10:39 pm
Location: Melbourne, Australia
Contact:

Post by Wayne Baker »

Most likely the AWB. I had this problem when I had my 5DmkII set to AWB. Once I switched to daylight, under the bright white LED's that are somewhere around 5500K, I get much better results that require almost no adjustment in camera raw... Worth doing a custom white balance setting under those tungsten halogen lights....

:D

rjlittlefield
Site Admin
Posts: 23561
Joined: Tue Aug 01, 2006 8:34 am
Location: Richland, Washington State, USA
Contact:

Post by rjlittlefield »

Gérard, thanks for the detailed illustrations of your interesting and elegant setups.

I have split that post off into a topic of its own, over in Macro and Micro Technique and Technical Discussions. It fits better over there, and will be easier to find later.

See HERE.

--Rik

Gérard-64
Posts: 256
Joined: Mon Jun 02, 2008 7:16 am
Location: Pyrénées atlantiques-France
Contact:

Post by Gérard-64 »

Thanks Rik.

Post Reply Previous topicNext topic