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GFX 50S: Autofocus Points????


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One thing I haven't seen anywhere is what the distribution of AF points across the viewfinder the GFX 50S has.

 

Is it better than the Pentax 645Z:

 

645z_vf_zpsstrpiwvq.jpg

 

I appreciate there are no PDAF points, and it is all CDAF, but I am curious to know if it has more than the one AF point of the Hasselblad X1d. 
 

Edited by Sator-Photography
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BTW I already know the answer to this question.

 

There is fairly extensive AF point coverage on the GFX 50S, and it is similar to that found on the X series. Yes, I know it is CDAF, not PDAF. Yes, I know there are no PDAF points on the Sony 4433 sensor. No I never said there were any PDAF points on there. Yes, I do know that the GFX 50S is a mirrorless and doesn't have a dedicated off-sensor PDAF autofocus sensor like the 645Z (and which is limited in size thus restricting the PDAF points to the centre of the viewfinder). 

 

Yes, there still is a point to the question of CDAF autofocus point coverage because the Hasselblad X1d has only ONE (yes, one!) AF point, though there are apparently plans to improve this in an upcoming firmware upgrade.

 

CDAF points do not necessarily always cover the entire viewfinder. Here for example the Sony a7, which has CDAF autofocus points that covers much but not all of the viewfinder:

 

a7FocusPoints_zpsoxu55wuv.jpg

 

These CDAF autofocus points are not small, well defined points or crosses, but they are usually called points nonetheless. If others want to come up with their own preferred terminology, that is 100% fine by me :)  

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This is a bit like asking how much gas fits into an electric car. ;)

 

There are no physical CDAF focus points in mirrorless cameras, it's all software. So there are as many focus frames as we (or Fuji) likes, and they can come in all shapes and sizes. Current X cameras offer up to 325 AF frames. They could also offer 700 or 1500 frames, it's just a matter of changing the firmware. The maximum number of frames in the GFX is still unspecified, current working samples simply run the X-T2 firmware. Obviously, the entire sensor can do CDAF, and the GFX will work just like any previous X camera, where CDAF frames cover almost the entire sensor area.

 

I assume there will be feedback from X photographers who will do beta-testing. There will also be feedback from me once I get a sample that offers more features than the current working samples.

 

After 5 years of hard learning, Fuji knows how to implement fast and accurate CDAF focussing and focus tracking, and they have a very capable processor. IIRC, the GFX will also offer face / eye detection focus.

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BTW that's Sony that's calling them CDAF "points" in that quoted diagram. Whether they are software based, based on the main sensor, or on a dedicated autofocus sensor, they are still commonly called "points". Hasselblad too are talking about increasing the number of CDAF "points" on their X1d from having just one point smack bang in the middle! If you want to insist that they be called something else that's fine by me. I promise not to be upset  :lol:

 

The thing is that because of limitations in processing, as formats get larger, the CDAF coverage over the viewfinder often becomes proportionately less and less with every increase in sensor size. That's why the question this post started with is still a perfectly reasonable one. But I've already answered my own question: CDAF coverage is widely distributed across the viewfinder as on X series models and not just restricted to a single point in the centre as it is currently on the X1d. 

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Well, base on Kai's video, it has 91 focus points. 

 

 

 

It was simply set to 91 points with the X-T2 based beta firmware that was on the working samples. So what? The actual GFX firmware wasn't on the working samples, as it would have revealed specs that Fujifilm wants too keep confidential for now.

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I just wish if GFX has both PD and CD AF.

 

Without a Sony sensor that supports PDAF, this is unfortunately exactly what you imply: wishful thinking. The second generation GFX will probably be named GFX 100S and sport a faster Sony CMOS 100 MP sensor with (hopefully) PDAF pixels. Toshi clearly hinted at future models and that the lenses are ready for 100 MP.

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When Sony developed the current 50MP 33x44 and 100MP "full 645" sensors, the market opportunity was SLR systems that had used CCD sensors and relied on their own PDAF module for AF. Now that Hasselblad and Fuji have introduced mirrorless systems, it is much more likely that Sony will include PDAF points in the next 33x44 sensor.

 

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Without a Sony sensor that supports PDAF, this is unfortunately exactly what you imply: wishful thinking. The second generation GFX will probably be named GFX 100S and sport a faster Sony CMOS 100 MP sensor with (hopefully) PDAF pixels. Toshi clearly hinted at future models and that the lenses are ready for 100 MP.

 

 

Fuji does not use Sony sensor. Fuji said GFX using quite different sensor than Pentax, Hasselblad, and Phase one are using. 

 

http://www.popphoto.com/fujifilms-medium-format-gfx-50s-digital-camera-first-impressions-and-frequently-asked-questions#page-4

Edited by Sunshine
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Fuji does not use Sony sensor. Fuji said GFX using quite different sensor than Pentax, Hasselblad, and Phase one are using.

 

http://www.popphoto.com/fujifilms-medium-format-gfx-50s-digital-camera-first-impressions-and-frequently-asked-questions#page-4

Designing a sensor is not the same as making one. Sony most definitely makes Fuji sensors, Fuji just adds their special sauce to the raw design Sony provides. As does Nikon for instance... Specs the sensor doesn't have natively, can't be added though, like no pdaf pixels for instance in this case.

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the sensor is the same Sony sensor for everybody... Fujifilm just "designed" a special microlens on the surface of the sensor

 

that's at least what I read in this dpreview interview: http://www.fujirumors.com/fujifilm-gfx-dpreview-interviews-fuji-manager-toshihisa-iida-design-challanges-future-adapters-lot/

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