I used four M lenses with my Sigma FP. Here is a write up on their performance.

Disclaimer: This is not a full review of the Sigma FP. This write up is restricted to the ‘stills’ mode and more specifically the performance of M lenses on the Sigma FP.

Sigma FP philosophy: The FP is NOT meant to be a full fledged, all frills, stills camera. It is meant to be a modular cine camera with a very good sensor and thus can be used for stills also. It does an extremely good job in rendering still pictures but lacks certain very basic features which are almost a given in modern mirrorless cameras. I would have loved an articulating screen and some sort of EVF, at least as an attachment, but it lacks both, which reinforces the fact that it was not intended to be a full time stills camera.

M Lenses on the FP: The small form factor of the FP yields itself to small M lenses very well. The balance is right and the kit is innocuous, which is a boon while shooting street and candid weddings. With any other AF lenses in the L Alliance, the kit becomes front heavy and beastly. It also looks ugly.

The Camera has no way of reading the lens profiles so you’ll have to remember what you used when.

The Adapters: I used the M lenses with two adapters, the Leica M to T/L adapter and the Novoflex M to L adapter. Both adapters are extremely good, well built and fit snugly without any play.

The Lenses: I used the Voigtlander 21mm Ultron, 7 Artisans 28mm f1.4, Leica Noctilux 50mm and Leica 75mm Summilux.

Manual Focus Aid: Focus Peaking works extremely well on this camera. I hardly had shots with shifted focus. Focus peaking nails focus every time. Obviously when used wide open it is easier to achieve critical focus than when used with a narrow aperture and wide angle lens and it is red all over. 

EIS: Electronic Image Stabilization cannot be switched when shooting DNG therefore it is useless if you are using the FP for a professional shoot.

The viewfinder accessory when attached enlarges the view, has diopter correction and shields the LCD from ambient light. It is highly recommended. On the flip side it increases the length of the camera and you can shoot only from eye level.

Leica 75 Summilux: This lens performs the best. The rendering of the 75 lux is legendary and its brilliant on the FP too. Here are some pictures where only brightness was adjusted, no retouching done. Lens profile of the Leica 75 Noctilux was applied in Photoshop.

WB: Auto

No Flash: Only modeling lamp was used for studio shots

Picture Profile: Standard

ISO: Mentioned on each picture

Some pictures which were fully edited and retouched:

 

Leica 50 Noctilux: Again, the rendering is fantastic. There is a vignette wide open but focus works perfectly wide open with focus peaking and the colors and contrast are beautiful, just like using on a Leica camera. None of these pictures are processed or retouched. Only brightness was adjusted. Lens profile was chosen in Photoshop.

WB: Auto

 

Voigtlander 21mm/7 Artisans 28mm: On both these lenses there is slight corner smearing. Leica sensors have algorithms to take care of the light hitting the corners but even though they are part of the L Alliance, there seems to be no impact to take care of this anomaly. 

21mm Ultron lens profile applied in Photoshop. A green cast is clearly visible in the corners.

WB: Auto

Unedited pictures

7 Artisans 28mm f1.4: Leica 28 summilux profile was applied in Photoshop. Color cast clearly visible in the sides/corners.

 

I love the form factor and ease of use so I will be using the FP as my second camera for Weddings alongside the brilliant Panasonic S1 and since both have the L Mount I can use all my lenses.

Here is a full album shot with the FP and S1. The file names starting with SD are with the Sigma and P with the Panasonic. http://www.thirdeyestudio.net/album/goa-wedding-of-dhriti-and-sharan/

Here is a blog on how M lens perform on the Fuji GFX 50R

Leica M lenses on the Fuji GFX 50R