Lepadella

[bernhardinho]

Hi everbody

welcome to 2007!!

Here is Lepadella ovalis. Brightfield and oblique l., flash:








Bernhard

[ralfwagner]

Hello Bernhard,

well defined details in these shots. The last picture is my favorite one because it shows the ciliae (or cirri or what else is the correct word?) very clear.

[MacroLuv]

Very nice!
Wondering why that kind of microscopy photographs often looks like a hand - draws. Maybe because of milky white or creamy background.
By the way folks, how you get that butter creamy milky backgrounds?
Don' take in bad part for ignorant but benevolent and honest person like me.

[gpmatthews]

Nice images - I like the last one especially

[rjlittlefield]

By the way folks, how you get that butter creamy milky backgrounds?

Nikola, I'm not sure what you're asking.

With brightfield and oblique illumination, the color of the background is just the same as the illumination light, of course as filtered through many pieces of glass and then interpreted by the camera. The exact color as it appears in postings is determined mainly by the "white balance" setting of the camera. White balance for microscopy can be more challenging than most ordinary photography. That's because with many scopes, turning down the brightness is done by reducing voltage to a light bulb filament, which can drop the color temperature a lot, more than some cameras are prepared to handle. Many cameras don't balance this light to exactly gray (R=G=B), but instead to a yellowish tint. If I read correctly, these shots of Bernhard's are flash, probably with lots of blue in the illumination, but the same principle holds -- the color in the pic is the color of the illumination, as interpreted by the white balance of the camera.

There are many other types of microscope illumination that put colored or polarizing filters in the light path. For those, the background color can be much different from the color of light provided by the illuminator.

If you're asking about the smooth texture of the background, well, it's just all out of focus!

--Rik

[bernhardinho]

Hi Nicola

Rik already explained it very well. I'm not very experienced in flash fotography yet. So when using the flash I set the camera white balance to the preset flashmode. The pics then turn out to be rather yellowy in brightfield and a bit more grey in oblique light (esp. in higher mag). Search me, why!!


Bernhard

[bernhardinho]

Hello Bernhard,

well defined details in these shots. The last picture is my favorite one because it shows the ciliae (or cirri or what else is the correct word?) very clear.

Hi Ralf

to my knowledge, cilia should be correct.

Bernhard

[svalley]

Very nice. I'm going to have to try my hand at this if I ever get time.

[beetleman]

Lots and lots of details in these pictures Bernhard. All three are great.

[MacroLuv]

Rik and Bernhard, thanks for explanations. It sounds very reasonable.
I have no experience in microscopy. I only noticed some photos with more milky background and others much more grayish or colorless (like water itself).

[rjlittlefield]

Nikola,

White balance is a tricky subject. The camera that I mostly use for microscopy is Canon SD700 IS. See this article in dpreview for a little discussion of how strangely it handles color balance. Mostly I try to remember to custom white balance or use the incandescent preset, but sometimes still I end up going into Photoshop and using level adjust to match the RGB humps in the histogram. These approaches all produce neutral gray, R=G=B, not the more yellow "milk" color that sometimes looks better.

Bernhard,

It's interesting that switching to oblique changes the color balance. I've only played with oblique a little, and I did it by putting in little obstructions like darkfield stops but smaller. I didn't notice color shift with that approach. Does your setup insert a printed filter, and if so, could the transparent portion be a little bluish?

--Rik