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Ultra wide lenses

Lenses Ultra wide angle lenses are one of the groups that have fun and practical uses, in confined areas. An ultra-wide lens can absorb a subject and its surroundings because of its large viewing angle. And by using facial images taken from a close distance from the subject, she distorts the appearance of people to the extent that they become unrecognizable.

This is due to the aberrations common with ultra-wide lenses, and cylindrical aberration
of them in particular. In most cases, this can be detected by looking through
The lens is connected to a camera: the straight lines at the edges of the field appear curved and curved outward.
Besides, ultra-wide lenses give the photographer an enormous depth of field.
Because of its very short focal length, foreign objects in the lens can come out as sharp as the background.

"Canon" 20 mm / f / 2.8

This "Canon" lens may be far from the financial means of some, but the price is worth paying. This lens has received the highest level of importance, in this selection because of its wonderful resolution power and good workmanship.

This lens has a viewing angle of 95° skew, 62° vertical, and 84° horizontal. As for its marine composition, it is based on ten elements in nine groups, with its cylinder of 58 mm length x 76 mm diameter, it weighs 305 grams.

For use with filters. The lens accommodates 72 mm Threatis threads. The interface element diameter is only 40 mm in length, although ample space around the lens's viewing angle is reserved to counteract vignetting.

Zuiko 18mm f/3.5
This compact and light 18mm lens is typical of the OM series lenses. It weighs 250 grams and measures 42 mm in length x 62 mm in diameter.
What is immediately striking about it is its large camber front element.
This allows for a viewing angle of 100 degrees for the lens. At the same time, we find this challenge vulnerable to damage, that is, to scratches, fingerprints, rain, and so on.
As for the optical structure, it is based on eleven elements in nine groups, and the lens has an automatic correction mechanism that helps to treat focus deviation from a close distance.
The work of this lens is very good in general. Its only drawback was its high price, although it gives wider coverage than coverage

"Canon", not much equal to Tokina's coverage - much cheaper.

- Sigma 16mm f/2.8
From an optical point of view, this Sigma differs from the previous two lenses in that it is a fish-eye lens for a full frame that covers a viewing angle of 180 degrees, and unlike the circular image of fish-eye lenses, we find the full frame here and it does not give a circular image in the middle, with a diameter of 24 mm or equivalent. Instead it produces an image that fills the 24 x 36 mm rectangular structure.

Its aperture ranges from f/2.8 to f/22, with f/stops clicking each half-stop for more accurate exposure.

This Sigma lens comes with four 22.5mm filters that are attached to the lens barrel's screw-on housing. It comes with ultraviolet, red, orange and yellow filters, rated as normal (Y 52), (056), (R 60) and
The UV filter comes already attached to the lens. As for


The other one is placed in a plastic case located above the lens bag, and it is installed with a locking button bag on the front section of the lens, and this is rotated 60 degrees counterclockwise to remove the filter.
An ultraviolet filter can then be seen at the back of the front section, then it is screwed out to install the desired filter, then the two halves of the lens cylinder are reconnected again. This simply involves aligning the red signals on the cylinder and rotating the front 60 degrees clockwise. When this is done, the front and rear sectors are in place.

It comes with the lens as well as a special cover for it.
As expected, this sigma lens showed extreme cylindrical aberration. However, this can be attributed to its different optical design and wider viewing angle.

- “Tarmon” 17mm f / 3.5 It is the lens with the adaptable mount system (2) from
Lenses series - Tamron.
With this 17mm lens, you can get an adapter - not included with the price of the lens - to hold almost any lens.
This ultra-wide lens has four built-in filters: ultraviolet, (80B) blue transfer for color films, (81B) yellow used to reduce color temperature, and (Y2).
The filter loop is the one closest to the interface element.

The candidate is placed in his position by aligning the selected candidate with the white guide badge
at the end of the cylinder.
As for the aperture range, it is f / 3.5 - f / 22 with the same stops Tikka when half the pause / F.
We get to the visual achievement.
Here, a slight abbreviation occurred at the edge with the maxillary aperture. Clarity was good, but it is not sharp as in other lenses.

- "Tokina" 17 mm f / 3.5

It happened to this Tokina 17mm f/3.5 lens that it attracted attention due to its reasonable price compared to the rest of the lenses.
Its high score in the field of what it offers to the consumer reflects a wonderful clarity that was less than clear
Canon, by a small amount at the maximum aperture, but this was expected because the Tokina covers a wider viewing angle.

The lens has 67 mm filter threads. It is also easy to use, with a weight of 280 grams.
In addition, this Tokina lens comes with most of the usual mounting accessories.
Thus, the specifications and achievement it offers makes this lens a reliable choice⏹