Mamiya 120mm f4 Macro Lens (Digital)

I am getting a lot of use out adapted Mamiya 645 lenses on my Fuji GFX 50s ii. I have considered getting into DSLR scanning for my film work. It is supposed to be better than a flatbed scanner and faster but I find that hard to believe. My understanding anyway is that it is best to have a true 1:1 macro lens. There are two choices for the Mamiya 645, the 120mm f4 and the 80mm f4 macro with extension tubes. The 120mm gets great ratings in terms of lens quality and the extra trouble of extension tubes ruled out the 80mm f4 lens. I may have some trouble with scanning as a longer lens which will mean my copy stand will have to rack up higher but not far as the minimum focus distance is about 16 inched (40cm). 

Mamiya 645 120mm f4 Macro Lens

The other factor I began to consider was that this could be a new general use lens. I already get a lot of use out of my 150mm f3.5 Mamiya lens. It is great for intimate landscape and can be coupled with a 2x teleconverter for a longer focal length. I reasoned that 120mm is very close and the macro lens is only 1/2 stop slower. (There is a Mamiya 150mm f2.8 lens but then I digress!) I could use this as a regular carry lens and replace my 150mm f3.5 prime. I would get very closeup capability to add to the repertoire. 

I looked around eBay and found the better lenses were available in Japan. I ordered a reasonably priced one for about $400 + $38 shipping. The UK added 20% VAT. Not a bargain but I have had very good luck with Japan vendors. It took about 3 days to get here, and the lens was immaculate. In fact, it is hard to see that it has ever been used. I am very pleased in this regard. 

The lens is about 1/2" longer and quite a bit heavier than the 150mm f3.5 lens. Fully extended, it is much longer of course. The only thing that distinguishes a macro lens is the focus can extend further. (I am sure there is more to the optics for retro-focused lenses in macro applications, but this is the essential idea.) 

My first impression of the Fuji GFX 50s ii is that the lens is higher contrast. This is apparent when using focus peaking. Some lenses show lots of peaking, and some do not. My Olympus 135mm f2.8 for instance is brilliant in this regard. The Mamiya 150mm f3.5 not so much so. The new 120mm lens seems much better in this regard as well. This makes critical focus much easier. 

Below are some random images of my first time out with the lens. All of these are JPEGs are directly from the camera with no sharpening.

St Mary's Church
 Manual Focus 120mm f4 at f11

Focus detail (7x)

The steeple on the church became a point for checking focus. I manually focused using the Fuji focus zoom and peaking with the lens wide open at f4 then stopped down to f11. 

Random willow tree focused on foreground limb.

Hemingford Grey Church Tower

Church tower detail at f11

Reeds on river

First Signs of Spring Hawthorn Flower

The lens is nicely sharp. (I think this is the byproduct of making a good macro lens.) The hawthorn flower is a true macro shot and with the wind blowing and failing evening light I could tell I was in a whole other world which was much like large format work. You really need a tripod and no wind. The depth of field is very shallow, so the temptation is to think of focus stacking. Which of course I had to try. 

My subject here is a small ceramic fish sculpture. I set up a tripod and focused and shot a series of 9 images at f4 with each focused further down the line of the fish mouth. I then put it into Affinity Pro Version 1 and ran the focus merge. 

First mage of focus stack at f4

Final focused stacked image. 

Kind of fun for my first try. 

A quick test indicates the lens has a good coverage circle on my shift adapter and shows little vignetting. I will test this more thoroughly later.