The Asahi Pentax 50mm 1.4

I’ve been trying a few vintage 50mm lenses on my Sony a7r3 recently. I use a cheap adapter I found on amazon. There are no contacts, the adapter is there purely so that the focal plane of the lens is exactly on the sensor. The mount of a mirrorless camera is much closer to the sensor than the film was on the reflex cameras the lens was made for so the adaptor allows to change any mount (here a m42 screw) to the sony FE mount while placing the lens at the correct distance from the body.

The barrel of the Pentax lens is about 4cm long whereas the sony 50mm 1.4 in FE mount is nearly 11cm long. If you count the adapter, that adds 3cm, the total length is about 7cm. That is 7cm vs 11cm : a real gain in size. It actually places this combo at around the length of the sony FE 55mm 1.8 lens. The Pentax Asahi 1.4 is manual focus whereas the sony FE 50mm 1.4 is an autofocus lens and logically bulkier too.

Let’s talk about image quality a little. For me, the 50mm focal length is a great all round lens. I use it a lot for portraits but also for street and travel photography.

Sony A7RIII with Asahi Pentax 1.4 at f/1.4

I like the colours and the pop I get out of this lens. The photo looks nice and sharp until you zoom in 100% (but who does that ?)

Screen Shot 2018-05-12 at 15.31.48

You can see that the eye is in focus and pretty sharp but there is a dreamy quality to the picture. As I understand, these are spherical aberrations because the light passing through the outer portion of the lens wide open refracts differently to the light that passes through the centre of the lens. So when you close the diaphragm, the lens seems sharper.

To be honest though, I don’t mind this dreaminess and you wouldn’t notice it on a print.  Another portrait :

Sony A7RIII with Asahi Pentax 1.4 at f/1.4

On both these portraits, I like the bokeh on the background. On this second photo, taken at a photography exhibition, you can see sturdy metal grids with photos hanging off them. A busy background to blur out and I like the result.

So how it is for outdoor, more candid photography? Well, the only thing to master is the focusing. All the photos in this article were taken at f/1.4. Why get a 1.4 lens if you can’t use it at this aperture? That doesn’t mean to say you should always use a lens wide open, quite the contrary in fact, but if it works at f/1.4 then I can use it at any aperture.


It is a difficult task to photograph someone moving, even in a predictable way with a manual focus lens. On a small screen this photo looks roughly ok but a 100% crop shows a severely blurred image.

Screen Shot 2018-05-26 at 16.15.19

If we look at another one :


This one looks much better, the man was shuffling forward quite slowly. The 100% crop shows a lack of sharpness on the sharpest part of the photo :

Screen Shot 2018-05-12 at 15.24.19

I could get away with this one I think. The last photo I have taken during my test is nice and sharp, the subject however wasn’t moving. I still had to take the photo as quickly as possible before she moved away.


I really like the background blur, I find that the lens has a real 3d pop to it.

Some conclusions: 

  • It is a great lens, I love the rendering, especially for portraits.
  • Bokeh is very nice, even on difficult backgrounds
  • The transition from sharp to out-of-focus is smooth. This gives the lens a nice three dimensional look.
  • Focusing is difficult on moving subjects when the lens is wide open. I had more failed attempts than successful ones. I know that sharpness isn’t everything, but standards have changed a lot since the 1960’s and a reasonably in focus subject is mandatory in my mind.

So if you find one second hand in a flea market that looks in good condition, get one! You won’t regret having such a tiny lens that has so much character!







Faces of …. Thailand

Last november, I posted a photoessay called Faces of … Rajasthan, a series of portraits I took with the Fuji x-t1 and the 56mm f/1.2 (85mm equivalent) while visiting India. In october, I went to Thailand. I took the x-t2 and the 90mmf/2 lens (135mm equivalent).

Faces of Thailand 1
Fuji X-T2 + XF90mmF2 @ f/2.8 + 1/900s + ISO 200

I was easy to engage people to take portraits although I speak no Thaï and English is not widely spoken. In that respect, I enjoyed India more because I could chat with local people. I used sign language and got along fine.

Fuji X-T2 + XF90mmF2 @ f/2 + 1/125s + ISO 800

The 90mm focal length is a different beast to the 56mm. I got mainly headshots standing at a couple of metres back. From a distance of conversation with the 56mm you have the choice to step back and get a head&shoulders or step forwards and get a headshot. With the 90mm, if you don’t move, you get a headshot. If you want a wider shot, you have to move back several step and I find this a bit awkward, it looks as though you are moving far away from the person you are shooting.

Fuji X-T2 + XF90mmF2 @ f/2.5 + 1/550s + ISO 200

The shutter speed is much less forgiving than with the 56mm, at 1/125s, the eyes are not always tack sharp. A slight movement of the subject or the photographer is all it takes. At 1/250s I get more consistant results. I will know next time… live and learn!

Fuji X-T2 + XF90mmF2 @ f/2.5 + 1/640s + ISO 200

I met some fabulous people, the two guys above are friends and were chatting in a park in Bangkok. I went up to ask them if and where the komodo dragons were (yes, they live freely in the park!).
The following pictures are from a tribe village in the north, near Chiang-Rai. A controversial visit to be sure, but the people were friendly to those who tried to communicate a little.

Fuji X-T2 + XF90mmF2 @ f/2 + 1/125s + ISO 800


Fuji X-T2 + XF90mmF2 @ f/2 + 1/750s + ISO 200

Next is a little girl I photographed in Chiang-Mai. She was with many others at the foot of a temple, dressed up in traditional costume to ask for money of tourists.

Fuji X-T2 + XF90mmF2 @ f/2 + 1/1500s + ISO 200

This lady was also at the temple, selling flowers. She was very friendly and has a great smile.

Fuji X-T2 + XF90mmF2 @ f/2 + 1/1250s + ISO 200

A kind man I met at a temple in Chiang-Mai who was keen to chat (he speaks good English) and give us all the best places to visit. He works at an Elephant sanctuary and was visiting Chiang-Mai himself.

#58 A
Fuji X-T2 + XF90mmF2 @ f/2 + 1/140s + ISO 200

A burmese monk visiting the golden triangle where the Mekong meets Laos and Burma. He was visiting with other monks, taking photos of everything and got a few selfies with our children!

Fuji X-T2 + XF90mmF2 @ f/2.8 + 1/500s + ISO 200

The Thai are a great mixture between traditional and modern. As the county was in official mourning after the death of the king, most people were wearing black or dark clothes. A strange sight indeed.

Fuji X-T2 + XF90mmF2 @ f/2.8 + 1/125s + ISO 640

We visited some small villages in the north of Thailand. The tourist trade helps bring some revenue to an otherwise poor region.

Fuji X-T2 + XF90mmF2 @ f/2.8 + 1/420s + ISO 200
Fuji X-T2 + XF90mmF2 @ f/2 + 1/1250s + ISO 200
Fuji X-T2 + XF90mmF2 @ f/2 + 1/1900s + ISO 200

This lady was weaving at her house, a little of the main street. Her husband was peeling palm tree bark and chewing it. I went up to see and his made me taste. It is very bitter!

Fuji X-T2 + XF90mmF2 @ f/2.8 + 1/125s + ISO 250

A labourer working to clean around a temple before a royal visit. He was using a large wooden tool to stamp the ground to make it firm. He let me try and had a good laugh!

Fuji X-T2 + XF90mmF2 @ f/2.8 + 1/480s + ISO 200

This lady was sitting at a geyser pool in water nearly 70°C. Good for the joints apparently. It nearly burned the skin off me!

Fuji X-T2 + XF90mmF2 @ f/2 + 1/550s + ISO 200