X2D, GFX manual focusing accuracy

[JimKasson]

In an earlier thread, I posted results of manual focusing on a Siemens star with the 38mm XCD on an X2D 100C and a GF 45mm on a GFX 100S. The GFX yielded more accurate results with less scatter.

I was asked to run a test with the same lens on both cameras. I have done so, using the Zeiss Otus 55mm f/1.4. I set the lens to f/4. My first run with the GFX was with one of my usual focusing setups: red lo peaking, max magnification. I then reduced the magnification to approximately match the XCD magnification, and turned off the peaking.

Here are the stats for all three series, for both horizontal and vertical edges.




MTF50 in cycles per pixel. This is a decent metric for sharpness. Higher is better.

The GFX with peaking is both more accurate and has a lower standard deviation (std) than the X2D with magnification on. But the difference is not as great as before. I think that's because the Otus has a much longer focus throw than the XCD 35.

When I lowered the magnification and turned off peaking on the GFX, I got worse results than with the X2D.

My conclusion is that there's nothing wrong with the X2D's finder resolution. It is probably better than the GFX 100S. But without peaking, critical sharpness will be more elusive than with the GFX 100S.

I see no reason why the X2D can't add peaking in a future firmware release.

Jim

--

the last word the last word - Photography meets digital computer technology. Photography wins -- most of the time.

Photography meets digital computer technology. Photography wins -- most of the time.

blog.kasson.com

 

[Laci55]

Sorry for a question about the GFX 100s here...

Where in the menu could I choose the peaking level sensitivity on the GFX 100s? I can not find this option...

 

[Stan Disbrow]

Hi,

Yep. What I always call a Simple Matter Of Programming. Or, SMOP for short.

That always drove my Software Engineering compatriots into fits of conniption, of course. Cries of It Ain't That Simple and whatnot.

Then I'd take 20 minutes and add what I wanted to the source code and recompile and load. Instant new feature or, far more likely, a software bandaid on a hardware problem. But a code work around is far faster than a board turn.

Note, though, all niceties such as comments in the code wasn't happening. A true hack job, to be sure.

All grumbling ceased and was replaced by looks of horror. The manager of software development gave me Mr Yuck stickers to put on all my diskettes (I have been at this a long time, back to the days of 8" hard sectored diskettes).

No one wanted to grab any of my junk by mistake! And, I don't blame them.

And I won't describe similar efforts at mechanical engineering by what was seen as an electrical engineer. But I grew up in a machine shop and learned all that mechy stuff first. Besides, so much is a combination of mechanical and electrical and anyone who is purely in either is bound to have issues due to not understanding the other side.

It all has to come together. So, I see Hassy adding features in future firmware releases, and this is just one of those.

Stan

--
Amateur Photographer
Professional Electronics Development Engineer
Once you start down the DSLR path, forever will it dominate your destiny! Consume
your bank account, it will! Like mine, it did!

 

[JimKasson]

Sorry for a question about the GFX 100s here...

Where in the menu could I choose the peaking level sensitivity on the GFX 100s? I can not find this option...

It's one of the choices in the standard Q menu set up.

 

[colinsurprenant]

Thanks for testing this. Hopefully focus peaking will make it soon on the X2D. I really like the fact that Hasselblad iterates on their firmwares and listen to the community (unlike others ... *cough* Sony *cough*).

Off topic but out of curiosity, which adapters are you using for the Otus on the X2D and GFX?

 

[JimKasson]

Thanks for testing this. Hopefully focus peaking will make it soon on the X2D. I really like the fact that Hasselblad iterates on their firmwares and listen to the community (unlike others ... *cough* Sony *cough*).

Off topic but out of curiosity, which adapters are you using for the Otus on the X2D and GFX?

Fotodiox for the Hassy, Steelsring for the GFX.

 

[spilla]

It seems like this test is user dependent. Jim, assuming you are the user, it seems possible that others less experienced with critical focusing may have different results, I expect favoring the GFX focus peaking further.

 

[Laci55]

THX Jim! I am not able to find this option but I do not want to torture You with this kind of basic questions.

 

[JimKasson]

THX Jim! I am not able to find this option but I do not want to torture You with this kind of basic questions.

If it's not there, add it to the Q menu.







--

the last word the last word - Photography meets digital computer technology. Photography wins -- most of the time.

Photography meets digital computer technology. Photography wins -- most of the time.

blog.kasson.com

 

[Laci55]

THX a lot Jim! I choose; red low... I suppose this is how it should be...

 

[JimKasson]

THX a lot Jim! I choose; red low... I suppose this is how it should be...

Whether you want low or high sensitivity depends on your lens and the contrast of the subject. You want the lowest sensitivity you can use and still see red specks in the image. The low sensitivity setting is not nearly as low as it should be, IMHO.

 

[Laci55]

Thank You so much Jim. When I saw the high and low choices at the different colors I thought it just was about the intensity of the color and not about the focus sensitivity... My own stupidity... Tested it now with low setting and it is working beautifully... Thank for all Your help!

 

[Erik Kaffehr]

Thank You so much Jim. When I saw the high and low choices at the different colors I thought it just was about the intensity of the color and not about the focus sensitivity... My own stupidity... Tested it now with low setting and it is working beautifully... Thank for all Your help!

We all learn, all the time

Best regards

Erik

 

[Erik Kaffehr]

It seems like this test is user dependent. Jim, assuming you are the user, it seems possible that others less experienced with critical focusing may have different results, I expect favoring the GFX focus peaking further.

I would call peaking at magnified live view an essential tool for making best use of a lens.

Best regards

Erik

 

[Laci55]

Yes, it is the very truth, specially for me...lol...

Have a nice evening