Fuji GFX sensor & lens IQ

[chrismuc]

1. I did a comparison between the Fuji GFX 50s (with Fuji GF 63f2.8) and Sony A7RII (with Zony FE 55f1.8) using base iso raw test pics from imaging resource. I opened both in ACR and scaled them up to 200% directly in ACR (no sharpening applied). Look at the crops: The GFX upscaled pic is so much sharper than the A7RII pic. It's quite amazing what Fuji succeeded to squeeze out of the 44x33mm Sony sensor (and the 63mm lens is very sharp of course).





2. Enclosed a pic from today: GFX + GF 110f2 @ f2. Focused with small out-of-center focus point, the AF perfectly catched the boy's eye. The lens is tack sharp at open aperture and zero longitudinal aberation (the ear in the unsharp zone behind does not show any green color fringing). Few other lenses like Otus or the Art 135f1.8 or maybe also the Batis 135f2.8 are on that level, possibly quite no other medium format portrait lens.

 

[ErikKaffehr]

Hi Chris,

Thanks for your samples, explanation and analysis.

Jim Kasson has done a lot of tests on the GFX lenses and found that they were either excellent or very, very good. He compares with the Otuses he has.

Jim has done a lot of systematic and "scientific" testing regarding longitudional chromatic aberration, and the GFX lenses indeed did very well.

It seems that 100MP is around the corner, question is how long it takes to get there. Ming Thein is director of strategy at Hasselblad now and he sort of indicates that next generation X#D is 100MP. So, it must be nice to have lenses that shine on 50MP and so will do on 100MP.

Best regards
Erik

1. I did a comparison between the Fuji GFX 50s (with Fuji GF 63f2.8) and Sony A7RII (with Zony FE 55f1.8) using base iso raw test pics from imaging resource. I opened both in ACR and scaled them up to 200% directly in ACR (no sharpening applied). Look at the crops: The GFX upscaled pic is so much sharper than the A7RII pic. It's quite amazing what Fuji succeeded to squeeze out of the 44x33mm Sony sensor (and the 63mm lens is very sharp of course).

View attachment 132524

View attachment 132525

2. Enclosed a pic from today: GFX + GF 110f2 @ f2. Focused with small out-of-center focus point, the AF perfectly catched the boy's eye. The lens is tack sharp at open aperture and zero longitudinal aberation (the ear in the unsharp zone behind does not show any green color fringing). Few other lenses like Otus or the Art 135f1.8 or maybe also the Batis 135f2.8 are on that level, possibly quite no other medium format portrait lens.

View attachment 132526

View attachment 132527

 

[Ben730]

1. I did a comparison between the Fuji GFX 50s (with Fuji GF 63f2.8) and Sony A7RII (with Zony FE 55f1.8) using base iso raw test pics from imaging resource. I opened both in ACR and scaled them up to 200% directly in ACR (no sharpening applied). Look at the crops: The GFX upscaled pic is so much sharper than the A7RII pic. It's quite amazing what Fuji succeeded to squeeze out of the 44x33mm Sony sensor (and the 63mm lens is very sharp of course).
View attachment 132525

The cyan square and the wall look sharper in the Sony picture. Do both pictures have the identical plane of focus?
Regards,
Ben

 

[daf]

1. I did a comparison between the Fuji GFX 50s (with Fuji GF 63f2.8) and Sony A7RII (with Zony FE 55f1.8) using base iso raw test pics from imaging resource. I opened both in ACR and scaled them up to 200% directly in ACR (no sharpening applied). Look at the crops: The GFX upscaled pic is so much sharper than the A7RII pic. It's quite amazing what Fuji succeeded to squeeze out of the 44x33mm Sony sensor (and the 63mm lens is very sharp of course).
View attachment 132525

The cyan square and the wall look sharper in the Sony picture. Do both pictures have the identical plane of focus?
Regards,
Ben

I agree, the sony shot looks out of focus on the bottle... would be interesting to have the raws files

 

[ErikKaffehr]

Hi,

If we upsize an image past it's native resolution it will always suffer. Also, the aspect ratios between the GFX and the A7rIII differ, so if we crop for the vertical dimension, the GFX will have a more significant advantage than if we crop for width. 50MP vs 42 MP doesn't seem to be a lot of a difference, but it will be a larger difference comparing the short dimension.

So, I don't think the A7rIII image is out of focus, more that is going past native resolution.

It seems that that the Fuji lenses are extremely good, mostly. At least it seems so according to Jim Kasson's testing.

Best regards
Erik

I agree, the sony shot looks out of focus on the bottle... would be interesting to have the raws files

 

[chrismuc]

The cyan square and the wall look sharper in the Sony picture. Do both pictures have the identical plane of focus?
Regards,
Ben

good point
maybe very slightly different
here are the links to the raw files
Sony:
https://www.imaging-resource.com/PRODS/sony-a7r-ii/A7R2hSLI000100NR0.ARW.HTM
Fuji:
https://www.imaging-resource.com/PRODS/fuji-gfx/GFXhSLI000100NR1.RAF.HTM

 

[DB5]

The Sony definitely looks back focussed. Or it could just be that it has a little more depth from equivalency.

All these internet testers are pretty useless, IMO. DPR in particular are very inconsistent and sloppy.

 

[dchew]

The Sony definitely looks back focussed. Or it could just be that it has a little more depth from equivalency.

All these internet testers are pretty useless, IMO. DPR in particular are very inconsistent and sloppy.

We are at the point in resolution where a setup like this is not adequate for sharpness evaluation. Too little depth of field in the image to evaluate anything except the actual focus point, wherever that was. The scene has to be totally flat (and how often do we get that - or want that - in the field?). I've been driving myself crazy evaluating a new lens and recalibrating my STC after adjusting the tightness of the sliding back. Oh the things we can see in an image at 100%!

Dave

 

[daf]

good point
maybe very slightly different
here are the links to the raw files
Sony:
https://www.imaging-resource.com/PRODS/sony-a7r-ii/A7R2hSLI000100NR0.ARW.HTM
Fuji:
https://www.imaging-resource.com/PRODS/fuji-gfx/GFXhSLI000100NR1.RAF.HTM

I've quicly played with the raws, and definitly they are not focus on the same spot.
if you look at the fabrics on the left up on the the pencil, the sony is so much sharper ... Well we can only agree that now all thoses system are so good that it is very dificult to test them correctly.

 

[ErikKaffehr]

VFA targets more suitable for lens evaluation

Hi,

The studio scene is not a constant configuration. For lens evaluation the VFA target is more optimal:

https://www.imaging-resource.com/PRODS/sony-a7r-iii/A7R3hVFAI000100.ARW.HTM

https://www.imaging-resource.com/PRODS/fuji-gfx/GFXhVFA000050.HTM

But, in real life, you would need a very large test target for proper tests, as proper tests are often done at 40-50X focal length. So a 176x132 cm target is needed for 44x33 mm.

Jim Kasson say that most of the Fuji lenses he tested are extremely good, while the 63 mm prime is just excellent. Just to say, Jim has tested a lot of lenses.

Best regards
Erik

 

[DB5]

I downloaded a few of the shots from this imaging resource site and I have to say i am really quite impressed by how the Sony A7R III relates and compares with the Medium Format offerings.

The Fuji GFX certainly has the edge over the Sony but the only thing that is really significantly better is the Phase One XF100.

 

[Mark C]

...the only thing that is really significantly better is the Phase One XF100.

At almost six times the price of the GFX I'll stick with the Fuji, thanks.