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Sigma Sd Quattro, applications for Palaeontology

Sigma Sd Quattro macrophotography fossil photography

The image quality of the Sigma SD Quattro has been a real surprise for me. I tried it in a professional context and the camera revealed as an excellent tool for palaeontological documentation. I explain here how and why.

Main features, pros and cons of the Sigma SD Quattro have already been extensively described in many sites and here on Nikonland byMauro Maratta in his  articolo, that I recommend reading (it's in Italian Language by the way) . 
I will not repeat them  here. I will instead show how this unusual camera surprised (and enthralled) me as a tool for my work, giving me a very special user experience.
I am a vertebrate Paleontologist and my field of interest are fossil reptiles of the Triassic (roughly 250-200 million years ago) . I published over sixty scientific papers and also have a lot of teaching and popular education activities in my University Department. 
 
No need to say that photography  plays a fundamental role in Palaeontology both for illustration of one's studies and for didactic purposes.
 
Since fossils are amongst the most quiet things (along with rocks) in the natural world, the main shortcomings of the Sigma Dp Quattro, concerning ISO, reaction times and so on, become irrelevant. With a good stand or tripod and right lights, one can take photos at 100 ISO with proper apertures and exposure time,s without any worry. Thus, the shortcomings are gone, but the good qualities are still there.  Mainly, as we will see later, the richness of detail and the perception of three-dimensionality that  the camera gives to images. Something I believe can be obtained only with much more expensive or bulky (or both) equipment.
 

Immagine Allegata: ammo.jpg

 

A Jurassic Ammonite

 
 
However, what renders the photos taken with the Sigma Dp Quattro really different (and useful)  for my work,  does not concern photographs of complete specimen to be published on scientific journals (where, given the requested sizes, any good or decent DSRL will do the job) but rather the great sharpness of fine details, and the usability of even the biggest crops.  This is a plus both for research and for teaching. 
 
 
I take a photo of this Ammonite that still has the shell preserved. a rather uncommonevent. The specimen is about 4-5cm in diameter. I photographed it with the Sigma  50mm f1.4 ART and the Achromatic close up lens Marumi 3x, because a 105mm macro Sigma wasn't available for the test. Note: all photos have been taken with the 50mm f1.4 ART with or without the Marumi according to need.
 

Immagine Allegata: ammonitesutr.jpg

 

 

Below, the 100%crop:

 

Immagine Allegata: sutures.jpg

 

 

And here comes the first surprise:  You can clearly see the broken shell layers, the sutures (those arborescent lines) and the sediment that filled the shell cavity. I never saw it so well in a photo, especially in a huge crop, taken with a camera of this price level. Surely the crop can't be printed, but its more than good for didactic purposes, in fact I used it in my power point for my lesson on fossil cephalopods last Friday.
 
 
Section of another Ammonite. This one is pyritized (that is, it is  encrusted by iron sulphide, due to a reaction that occurs in anoxic sea bottoms often by action of bacteria).
 

Immagine Allegata: piritizzazione.jpg

 

 

Again, a 100% crop:

 

Immagine Allegata: incrostazione.jpg

 

Again, I was stunned by seeing the "step" in thickness between the black pyrite encrusting and the shell septa. This one has also been used  for my lesson.
 
Now,  Bivalves:
 
 
 
 
 
 
 
 
 
 

Immagine Allegata: bivalvi.jpg

 

Would you like to see the growth lines? Here they are:
 

Immagine Allegata: strie.jpg

 

 

 

 Carboniferous Fern leaves:
 
 

Immagine Allegata: felci.jpg

 

 

you can see the little creases of the leaflets:

 

Immagine Allegata: foglie.jpg

 

 

Please take in mind that all the photos have been taken with a standard (as focal lenght) lens, with a  true macro there may have been much less need of cropping, greatly enhancing image quality and usability. As for the following examples.
 
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