Tadpoles are beautiful

This is not because I have processed the photo in a special way.  The vibrance of the colour depends very much on light that falls on the subject. I photographed this tadpole using flash, and the colour is original. Well, of course, I added saturation in postprocessing – maybe even a little too much, compared to other my shots of tadpoles. Anyway, I was surprised how beautiful tadpoles actually are. We, people, don’t notice it when we are looking at these little creatures in muddy water.

Image

Source: Nature Images by Arthur Tiutenko: Pelophylax lessonae / Pool Frog

Close focus wide-angle lenses for SLR cameras

For an article on herp photography that I am currently preparing I have reviewed all wide-angle lenses with minimum focus distance below 20 cm.

Sigma 10mm f2.8 EX DC HSM Fisheye

With only 13.5 cm this lens has the closest focus among SLR wide-angle lenses. As all other Sigma lenses, this one exists for Canon, Nikon/Fujifilm, Sony, Sigma, Olympus, but unfortunately it is for APS-C cameras only, i.e. it would produce a smaller image on full-frame. The Canon version has an EF-S type mount and is not compatible with full-frame cameras.
Due to smaller APS-C sensor, the Sigma 10 mm will draw a similar image as a 15 mm fisheye lens would do on full frame. I don’t know if the shorter focusing distance would be of advantage. Anyway, if I had an APS-C camera, I would have preferred this lens for small amphibians and reptiles, and for large invertebrates.

AF DX Fisheye Nikkor 10.5mm 1:2.8 G ED

Naturally this lens is available only for Nikon, and for Fujifilm cameras that have the same mount. The focusing distance is remarkably short — 14 cm, but a little greater than on Sigma mentioned above. Like the Sigma 10 mm, it is supposed to be used with APS-C sensors. Unlike Canon’s EF-S, Nikon’s DX lenses can be used with full-frame cameras but will result in reduced frame. The image captured with this lens would look as if the focal length were about 15 mm in full-frame equivalent, i.e. the field of view would be narrower. Since I use Canon cameras, I can’t tell anything concrete about this lens. To me it looks like Nikon’s counterpart to Sigma 10 mm fisheye.

Sigma 15mm F2.8 EX DG Diagonal Fisheye

It focuses at 15 cm and is the lens of preference by many herp photographers. I own a copy of it, too, and have used it frequently. It is a great quality lens that provides excellent IQ and is a unique lens for full frame. As of time of writing, it was out of competition: There are no alternatives for Nikon/Fujifilm and Sony because their own fisheye lenses focus minimum at 20 cm. For Canon there is a fisheye zoom lens discussed below, but the Sigma 15 mm is more value for the money unless someone really needs a shorter focal length that the Canon zoom offers. For close-up wide-angle photography of reptiles and amphibians this is the best lens among fisheyes — both for APS and APS-C sensors. Therefore, I have to recommend it without too many reservations to everybody who is interested in herp photography. Personally, I don’t like the bokeh of this one and actually of all Sigma lenses that I have seen so far. The other minor problem is that you have to set the exposure manually because cameras tend to overexpose when used with this lens.

EF 8-15mm 1:4 L Fisheye USM

The Canon EF 8-15mm 1:4, after it was released in 2011, was a unique lens among lenses SLR cameras because it was the first fisheye zoom ever made for APS sensor. (Note: The Tokina zoom lens mentioned above is supposed to be used with APS-C cameras.) For nature photography, it is usable only at the long end — 15mm. Then it is equal to the Sigma and has the same minimum focusing distance — 15 cm. Obviously, it is a Canon-only lens, unparalleled in other brands, but Sigma fisheye lenses for Canon are less expensive and provide similar or, as primes, even better image quality. Thus, only someone who strongly believes that Canon lenses are the best and for whom money isn’t an issue would prefer this lens to Sigma 15mm f2.8 EX DG Diagonal Fisheye.

Tokina AT-X 107 DX AF 10-17mm f/3.5~4.5 Fisheye

This is currently the only zoom fisheye lens optimized for APS-C sensors. Like Sigma 10 mm it focuses at 14 cm but can provide a narrower view field if set to greater focal length than 10 mm. Setting this lens to 17 mm significantly reduces the huge barrel distortion of a fisheye lens. Like Sigma fisheye lenses the Tokina AT-X 107 is a favourite lens of underwater photographers. For herp photography the greater focal length is more interesting because it helps to reduce the distortion with optics and not through cropping in software. Thus, if I had an APS-C camera and this lens I would use it at 17 mm all the time.
The images produced by this lens did not impress me when I saw them in reviews. My impression is that this lens is less sharp than the 10 mm and 15 mm primes made by Sigma. Reviewers also complain about chromatic aberrations that this lens is prune to. The images coming from my Sigma 15 mm are almost free of CA.

Carl Zeiss Distagon 2.8/25 t*

Zeiss Distagon focuses not so close as the fisheye lenses discussed above, but it appears to be a unique lens of its kind because it is a moderate wide-angle lens. Usually such lenses have a minimum focusing distance of 25 cm and more but this one can focus as close as 17 cm — only 2 cm farther than a fisheye lens. As for the time of writing, Carl Zeiss was producing the Distagon 2.8/25 T* only for Nikon, Pentax and M42 (screw) mount. However, any of these versions can be used on Canon with an adapter. The drawback is the need to set the aperture manually on the lens because even the best adapters do not transfer information from the camera. Therefore, I preferred the older version of Distagon 2.8/25 T* which has a separate aperture control ring.
The Distagon 2.8/25 T* has at least two advantages over the fisheye lenses: First, the extreme barrel distortion characteristic for fisheye lenses is absent in the images produced by it. Second, this lens is compatible with 58 mm filters, hence graduated and polarizing filters can be used with it. It is a very useful capability in herp photography because the upper 2/3 or 3/4 in an image that was captured with a fisheye lens are often overexposed when the exposure was measured on the subject — a frog or lizard on the ground. A graduated ND filter may help to solve this problem.
As in all Zeiss lenses, the image quality that this lens delivers is superb. The images have typical for Zeiss lenses smooth bokeh, excellent contrast and natural-looking colours. In terms of imaging performance and build quality it is the best lens in the line-up of close focusing lenses presented here.
The 2 cm greater focusing distance of Distagon compared to Sigma fisheye lens may be of disadvantage when the photographed subject is very small. However, a greater focal length may compensate this. Like all Zeiss lenses, the Distagon 2.8/25 T* is a manual-focus-only lens. However, it is not an issue when this lens is used for herp photography because for a close-up wide-angle shot of a reptile or amphibian any lens usually has to be focused manually.

Sigma 24mm F1.8 EX DG ASP Macro

This is the second non-fisheye wide-angle lens that I am aware in the league of lenses with minimum focusing distance of less than 20 cm. Though it focuses at 18 cm, it is still close enough for most subjects in herp photography. As all Sigma lenses this lens is being produced for Canon, Nikon/Fujifilm, Sony, Sigma and Olympus. There appears to be a consensus among reviewers of Sigma 24mm F1.8 EX DG ASP Macro that it is inferior to the rest of lenses in this list both in image and in build quality. Probably the most interesting in this lens is its maximum aperture of f/1.8 that is certainly of advantage if this lens used for low-light — not in herp photography, however, where a greater depth of field is important.
I am mentioning the Sigma 24mm F1.8 EX DG ASP Macro here for completeness and not for recommendation as a herping lens. However, it is inexpensive and someone who already has this lens may try to use it for herp photography.

Carl Zeiss Distagon 2/24 t* ZA

This is a specific lens for Sony Alpha. With 19 cm, it has the biggest focusing distance among the lenses in this line-up, but still it is less than 20 cm. Therefore I mention it here for the sake of completeness. For herp photography with a Sony Alpha camera a Sigma 15mm f2.8 EX DG Diagonal Fisheye should be a more suitable and even less expensive alternative. For the time of writing, the only existing Sony fisheye lens — SAL-16F28 16mm f/2.8 — had the minimum focusing distance of 20 cm and wasn’t an option at all.

We should remember that the focus distance is measured from the sensor plane to the subject. In real world the distance between the subject and the front of the lens — i.e. the so-called working distance — is what matters. To know this distance, we have to subtract the length of the lens and probably also the depth of the camera body from the official minimum focusing distance value. If, for instance, the length of Carl Zeiss Distagon 2.8/25 T* is 90 mm and the sensor is at least 2 cm behind the rear element of the lens, then the working distance is only about 5-6 cm. This is very close indeed if you consider that the subject in front of the lens may be a dangerous snake.