Lens review: The Porst Color Reflex MC Auto 50mm f/1.4 G

This review is about the Porst Color Reflex MC Auto 50mm f/1.4 F lens. I must admit that I hadn't heard of this specific lens before I was doing research on its bigger brother, the Porst Color Reflex MC Auto 55mm f/1.2 F lens. As it happens, an eBay seller had both the 55mm f/1.2 (early f/22 version) and 50mm f/1.4 for sale. The f/22 version of the 55mm/1.2 went for € 139. I was however intrigued by the 50mm/1.4 so I bid on it and was able to purchase it for a mere € 56.

Like its bigger brother this lens was made in Japan for the German Photo Porst chain of camera stores. I have since managed to find that the Porst lenses in K mount were actually produced by Cosina, thereby confirming my hunch. It is no surprise that both lenses have the same kind of style, the later f/16 version of the 55mm/1.2 and this 50mm/1.4 look very much alike. 

The 50mm/1.4 has a nice solid feel to it. You can tell that these were lenses that were made to last. 

Specifications:

Focal length:                        50mm

Minimal focus distance:        0.5 meters

Aperture:                             f/1.4 - f/22

Aperture blades:                  8

Lens elements:                    7

Diameter:                            49mm

Mount:                                Pentax K

Manufacturer:                     Cosina

Built:                                  1970s-1980s

Use

This lens is equipped with the Pentax K mount. As with the 55mm/1.2 its focus ring turns to the left towards infinity. Again this may seem a bit unnatural at first for Pentax users as the Pentax lenses turn to the right.

Focusing is smooth and in general, the lens has a nice feel to it. I've used this lens with Pentax film cameras and with a digital Canon EOS camera via an adapter. Due to the design of the K mount these lenses will not fit APS-H and full frame EOS cameras, the mirror will hit the back of the lens. K mount lenses will only work on EOS cameras with an APS-C sensor (much like the EF-S mount). 

Images

The images you see below were shot with a Canon EOS 90D set at ISO 200. These images were converted from RAW to JPEG, slightly cropped (to just show the chessboard) and resized. No other actions were taken in Photoshop.

f/1.4

f/2.8

f/4

f/8

f/16

As you can see at f/1.4 subject isolation is great! Wide open it also shows chromatic aberration (CA) which disapears when the lens is stopped down. At f/4 it is almost gone and at f/8 there is no sign of it. Wide open there is also some vignetting, although this does not show on these slightly cropped images. As with the f/1.2 version I found it hard to focus with this lens on the EOS 90D which shows, the f/2.8 and f/4 shots are slightly out of focus. When using these lenses solely on AF cameras I do recommend getting a split-image focusing screen for better accuracy.

In the field

I fitted the Porst Color Reflex MC Auto 50mm f/1.4 G to my Pentax LX, loaded it with Fomapan 100, teamed up with fellow photographer Joeri van Veen and headed out for some shots. 

Photo: Joeri van Veen

In the field the lens is easy to operate, the fact that it focuses the 'other' way round did not hinder me in any way. And as for the results, judge for yourself:

The harsh winter light posed no problems for this lens. Only when shooting directly into the sun the back light bleached out the subject somewhat as can be seen below.

All in all I found this lens to be a solid performer, both wide open and stopped down. When using it with the Pentax LX I found focusing no issue at all, whilst using it with a digital camera without a split-image focusing screen was sometimes challenging wide open. For the price this lens is a fine performer for as far as I am concerned, this is a keeper.