All My Blogs

Dendrobates leucomelas,  a lso known as the bumble bee poison arrow frog. I have written numerous blogs on the poisonous skin of amphibians (cane toad, rough-skinned newt, etc).  The toxins contained in the skin itself or in cutaneous glands can be formidable.  Most of the time, the active chemicals are produced by the animals themselves and are only toxic when ingested.  Neither point is true for members of Dendrobatidae (poison dart frog group). The poisons of the Dendrobatidae are somewhat varied but are all alkaloids.  Alkaloids as a group are potent chemicals, many with familiar names such as nicotine, caffeine, cocaine, and strychnine.  They are all nasty chemicals that affect parts of the nervous system and can cause organ failure and death in sufficient doses.  Most alkaloids come from plants, such as members of the nightshades. Poison dart frogs do not create their own poisons.  They get them from the invertebrates they eat.  But the...

Click on the links below to take you to the blog.  More below. 1.  Which axis to shoot along:    https://blogsbyericsvendsen.blogspot.com/2025/08/macro-photography-part-1-which-access.html 2.  Using a macro lens:    https://blogsbyericsvendsen.blogspot.com/2025/08/macro-photography-part-2-macro-with.html 3.  Reversing a lens:    https://blogsbyericsvendsen.blogspot.com/2025/08/macro-photography-part-3-reversing-lens.html 4.  Reproduction ratios:    https://blogsbyericsvendsen.blogspot.com/2025/08/macro-photography-part-4-understanding.html 5.  Focus stacking:    https://blogsbyericsvendsen.blogspot.com/2025/08/macro-photography-part-5-focus.html 6.  Macro flashes:    https://blogsbyericsvendsen.blogspot.com/2025/08/macro-photography-part-6-macro-flash.html 7.  Camera settings for macro:    https://blogsbyericsvendsen.blogspot.com/2025/08/macro-photography-part-7-camera-settings....

Blue tobacco hornworm - Left:  White background.  Right:  No background but with "halo" lighting. As reproduction ratios increases, depth of field decreases.  As you approach a 1:1 ratio, the depth of field becomes critical.  At f/4, a 1:1 reproduction ratio has less a depth of field less than 0.2 mm.  At f/16, that depth of field increases to about 0.6 mm.  At f/64, about 2.5 mm.  (note:  the apertures given are effective apertures and not actual). If you are stacking there is less of an issue as lower apertures means the background will be visible but highly blurred.  However, if you shoot at small apertures to maximize depth of field, the background will be pitch black for anything at distance.  This is assuming that you are not shooting with a very high ISO.  To keep from getting the black background, you have to make some changes. I love using white paper plates; they are bright white, stiff, and readily available....

Orchard Mason Bee approaching grape hyacinth.  Nikon D70, 105 mm, f/29, macro flash used. Insects have always been something that has fascinated me.  They are everywhere; it's hard to go a day without seeing them, with the possible exception of winter time.  As a child, I used to catch all sorts of invertebrates, both terrestrial and aquatic.  I read books on them and was filled with an insatiable curiosity.  Then, after graduating high school, I decided to follow my passion and did a degree in zoology. It was as a young adult that everything came together for me.  School cemented my great passion for living creatures.  I also joined a school newspaper as a photographer and my love affair with cameras grew exponentially.  This was in the early 80's when computing was still in its infancy; I found that I could work with codes and became handy at working with them.  The combined interests of creatures, cameras, and code was the exact elixir nee...

Rose weevil on wild rose flower.  Nikon 7200, 105 macro, f/45 @ 1/250 and ISO 200  We know that depth of field is affected by numerous factors including focal length, aperture, and point of focus (there are others as well, but these are the ones the photographer has direct control over in camera).  We also know that reproduction ratios correlate to depth of field in that the greater the magnification, the less depth of field there is.  What's cool though is that at any magnification, regardless of what lens is involved, and regardless of what accessories are used with it, depth of field is a constant for that magnification or reproduction ratio (given a constant aperture between all values). Let's look at three different macro lenses; a 60 mm, 105 mm, and 200 mm macro.  If each lens is focused on a subject giving the exact same field of view (same area at point of focus), the reproduction ratio for each lens would be the same.  The depth of field is also th...

Closeup of moth using bellow and reversed 50 mm lens.  Approximate reproduction ratio of 4:1. Getting reproduction ratios greater than 2:1 requires specialized equipment.  There are numerous ways to do it that range from bellows, microscope objective lenses, specialized macro lenses, and various different microscopes.  What they all have in common is the need for good quality optics.  Herein lies the rub.  It can be very expensive if you want to do it well. A second factor is that working distance tends to be measured in centimeters, sometimes millimeters.  Lighting your subject also is difficult because of that narrow working distance.  Lighting can only be done from the side as there is little room to put relatively large equipment in.   There are solutions, but often you will have to be inventive and adapt whatever stuff you have.   I can tell you that any one photo represents a lot of time invested.  There is equipment setu...

Golden stonefly nymph ( Hesperoperla pacifica ) photographed with 105 mm macro + extension tubes. Camera equipment and water don't play well together in several ways.  First off is the likely destruction of expensive items and second is the difficulty in getting decent shots of anything.  As a result, most of my aquatic macro work is done indoors (usually my trailer) with a simple but reliable setup. Aquatic creatures can be very small; many of them can really only be photographed using a dissecting or light microscope.  I will go into this on another blog.  A 1:1 reproduction ratio may not be enough to do the job for many organisms, so more magnification will be needed. Extension tubes are an excellent addition to any macro setup.  These metal cylinders have no glass; their purpose is to move the lens farther away from the camera.  You can use extension tubes on almost any lens, but where they really shine is with a macro lens.  This boots reproductio...