Tasco Essentials 8x42
| Magnification | Lens diameter | Angular field of view | Prisms | Eye relief | Weight | Price |
|---|---|---|---|---|---|---|
| 8 | 42 | 123/1000(7o) | BaK-4/roof | ? mm | 729 g | 299 PLN |
| Real front lens diameter |
Left: 42+/-
0.05 mm Right: 42+/- 0.05 mm |
8 / 8.0 pkt | ||||
|---|---|---|---|---|---|---|
| Real magnification | 8.05+/- 0.05x | 3/3.0 | ||||
| Transmission | 61.4+/- 1.5% | 3/25.0 | ||||
| Chromatic aberration | Medium in the centre, high on the edge. | 3/10.0 | ||||
| Astigmatism | Moderate. | 6/10.0 | ||||
| Distortion | The distance of the first curved line from the field centre compared to the field of vision radius: 25% +\- 5% | 2/10.0 | ||||
| Coma | Appears more or less in the distance of 70% of the field of vision radius and is huge on the very edge. | 5.8/10.0 | ||||
| Blurring at the edge of the FOV | The blur occurs in the distance of 80% +\- 5% from the field of vision centre. | 5/10.0 | ||||
| Darkening at the edge the FOV | Average. | 2.6/5.0 | ||||
| Whiteness of the image | More than a dozen percent of difference between red and blue light. The image is grey-brownish-yellowish. | 3/5.0 | ||||
| Collimation | Perfect. | 5/5.0 | ||||
| Internal reflections |
|
2.9/5.0 | ||||
| Housing | Quite big and not especially stylish, looking far from solid to boot. Slippery and smelly rubber padding which comes off near objectives. Rubberized and regulated eyecups. Produced in China. | 3.5/8.0 | ||||
| Focusing | Significantly big and ribbed central wheel with the working range of 560 degrees. It moves very unevenly, sometimes being heavy to turn sometimes working more loosely. Individual focusing on the right eyepiece done by a comfortable ring which moves the outer lens. | 2.3/5.0 | ||||
| Tripod | There is an exit hidden beneath a screw which also secures objective caps. | 2.5/3.0 | ||||
| Interpupilary distance | from 56.8 to 75.7mm | 5/6.0 | ||||
| Closest focusing distance | 4.05 metres | 0.5/2.0 | ||||
| Eyepieces FOV | Apparent field of view of 54.4 deg (according to simple formula) and 51.1 deg (according to tangent formula). | 7/20.0 | ||||
| Field of view | Measured by us amounted to 6.80 +\- 0.03 degrees and it was a bit narrower than stated in the specifications. Not a very impressive field of view for such a class of equipment. | 4/8.0 | ||||
| Quality of the interior of the barrels | Black but shiny inner tubes. Grey bottom. Some specks of dust on both prisms. | 3/5.0 | ||||
| Vignetting |
|
3.5/8.0 | ||||
| Prisms quality | Good quality BaK-4. | 8/8.0 | ||||
| Antireflection coatings | Bluish on the outer lenses of the objectives and eyepieces (look like single-layer ones). On the prisms and the inner part of the objective there are no coatings. Part of air-to-glass surfaces in eyepieces seem not to be covered as well. Medium intensity. | 1.5/5.0 | ||||
| Warranty [years] | 1 | 1/6.0 | ||||
| Final result | 47.9% | 91.1 / 190 pkt | ||||
| Econo result | 0pkt. |
Summary
Pros:
- sensibly controlled astigmatism,
- moderate coma,
- prisms made of BaK-4 glass.
Cons:
- very weak transmission,
- badly corrected chromatic aberration,
- high distortion,
- noticeable light fall-off on the edge of the field of view,
- truncated exit pupils,
- ugly and smelly rubber on the padding,
- focusing wheel has some slack,
- sharp image from the distance of over 4 meters.
 |
What can be written in the test’s summary of such a pair of binoculars? Is it really necessary to tear apart a piece of equipment which costs just below 100 Euro? The price itself already indicates that the results cannot be good; accordingly the binoculars’ performance is such that you could have tormented it long and hard. We don’t intend to do so. Let’s just focus on a transmission graph, presented below…
 |
It shows unambiguously what class of instrument we are dealing with here. A classic Porro device with the same parameters would have reached a better transmission level even without one single coating. Here, despite single-layer coatings on some air-to-glass surfaces the transmission is still very weak. All of this makes spending alomst 100 Euro on this pair of binoculars a very bad decision. You would make a much better use of that money trying to buy a 8x40 or 8x42 set of Porro binoculars.
 Tasco Essentials 8x42 and Fujinon 8x42 MF |
