Triplet-69-3 4/40. Review from the reader Radozhiva.

Rodion Eshmakov prepared a review of the fixed lens Triplet-69-3 4/40 (BelOMO) of the «Viliya-Auto» camera, which was transplanted to the EF mount especially for Radozhiva.

This overview will be brief because there is almost nothing to review.

Triplet-69 is a standard lens of Viliya scale cameras, with which many began to get acquainted with photography. More than 3 million cameras have been produced, the lens is extremely affordable and widespread. Moreover, it is non-removable, i.e. rework is required for use on modern cameras.

Triplet-69-3 characteristics: Optical design: triplet Focal length: 40 mm Relative aperture: 1: 4 Field of view: 55 degrees (for 35 mm film) Aperture: lens, square, automatic Features: fixed lens, aperture separated from the lens unit , built-in central shutter.

Features of adaptation and constructive T-69-3.

It would seem, what surprises can await after the T-43 during the alteration of his «brother» T-69? It turned out – there are enough of them. Despite the general idea of ​​adaptation with the T-43, a number of peculiarities surfaced while working on this lens.

And the first one is a lens diaphragm, which is controlled by automation. When reworking, there is absolutely no place for it – it is simply not clear where and how to place it, how to manage it. Therefore, it was decided not to bother and, for testing, make a lens without a diaphragm. It’s a pity – it would be interesting to get photos with his native square aperture.

The second problem was the helicoid, the stroke of which is rather small, and the thread pitch is large – in this case, the lens unit can make a maximum of half a turn, and (taking into account the absence of the MDF stopper), it will have to be caught further, which is very inconvenient. In the T-43, the helicoid has a small thread pitch, due to which such a problem does not arise – you have to twist the lens with great enthusiasm so that it falls out.

The third feature, on the contrary, is positive: the lens has an unexpectedly large back section, which makes it possible to adapt for full-frame SLR cameras! With a T-43, such a license plate will not work – its rear lens sticks out very far. Strictly speaking, it was this feature that caused the desire to get something from this small lens.

It can be noted that the lens cannot be fully converted for SLR cameras (with aperture and a convenient focuser) without significant investment and effort, unlike the LOMO T-43. However, this lens can be used on full-frame DSLR cameras, unlike the T-43, which is a decisive plus. Adapting both the T-43 and the T-69 to mirrorless cameras is almost equally simple

Optical properties of T-69.

As the simplest anastigmat for cheap cameras, the T-69 at an open aperture forms a sharp image only in the center of the frame. Even on my 600D, the edges are drowning in chromatic, coma and astigmatism. It’s a shame that due to the lack of aperture, you won’t even be able to try to get a sharp image across the field. The presence of vignetting is also clearly visible. The contrast can be assessed as satisfactory.

But the bouquet of aberrations inherent in the T-69 can be interesting in the field of art photography. Due to optical imperfections, the lens has an interesting twisted

0 replies

Legg igjen et svar

Want to join the discussion?
Feel free to contribute!

Legg igjen en kommentar

Din e-postadresse vil ikke bli publisert. Obligatoriske felt er merket med *