Pages: 1 ... 3 4 [5]   Go Down

Author Topic: GX 100 returned as it could not match my GFX 50S  (Read 3951 times)

Rand47

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1606
Re: GX 100 returned as it could not match my GFX 50S
« Reply #80 on: January 06, 2020, 03:09:12 pm »

You really need to have optimized work flows for the two cameras to compare them with final prints. One might require a different oprimized workflow than the other. Are you certain you oprimized both images to their best?

Youre absolutely right.  And my answer to your question is yes. 

Rand
Logged
Rand Scott Adams

nazdravanul

  • Full Member
  • ***
  • Offline Offline
  • Posts: 108
    • Stefan Iacob - visual artist
Re: GX 100 returned as it could not match my GFX 50S
« Reply #81 on: January 07, 2020, 07:01:42 pm »

While I appreciate all the testing and research you pixel peepers do, I have to just shrug and go shoot.  ;D

Sharon

 Good call ;D Have fun!
Logged

George_Cleansman

  • Newbie
  • *
  • Offline Offline
  • Posts: 11
Re: GX 100 returned as it could not match my GFX 50S
« Reply #82 on: January 08, 2020, 01:58:49 am »

As a very satisfied H6D-100c user I like to say that the biggest advantage of 100 MP in contrast to 50 MP is not the possibility of larger prints, but an important increase of oversampling regarding the demosaicing process with less artifacts. The GF and HC/HCD medium format lenses from Fuji by the way are very good, so this is not an issue regarding 100 MP.
« Last Edit: January 08, 2020, 02:15:53 am by George_Cleansman »
Logged

Jim Kasson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2281
    • The Last Word
Re: GX 100 returned as it could not match my GFX 50S
« Reply #83 on: January 08, 2020, 10:08:58 am »

As a very satisfied H6D-100c user I like to say that the biggest advantage of 100 MP in contrast to 50 MP is not the possibility of larger prints, but an important increase of oversampling regarding the demosaicing process with less artifacts. The GF and HC/HCD medium format lenses from Fuji by the way are very good, so this is not an issue regarding 100 MP.

I agree with what you're saying, except that I wouldn't call what's going on more oversampling. In fact, where artifacts show up it's because of undersampling. Increasing the sampling frequency by 40% reduces -- but does not eliminate -- the undersampling. Another way to eliminate it is to stop waaay down, but that has negative consequences as well.

I define oversampling as sampling at a higher frequency than the Nyquist frequency. I define undersampling as sampling at a lower frequency than the Nyquist frequency.

Jim

JaapD

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 270
Re: GX 100 returned as it could not match my GFX 50S
« Reply #84 on: January 09, 2020, 01:07:29 am »

Hi Jim,

I would define oversampling applying a sample frequency (pixel pitch) at more than twice of the sampled analogue bandwidth (the light from the lens projected on the sensor).
I would define undersampling applying a sample frequency at less than twice of the sampled analogue bandwidth.
The by you mentioned Nyquist frequency (Fs/2) is part of the digital domain, not the analogue domain.

Im sure you already knew this, right  ;)

Regards,
Jaap.

Logged

Lust4Life

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 705
    • http://www.shadowsdancing.com
Re: GX 100 returned as it could not match my GFX 50S
« Reply #85 on: January 09, 2020, 09:32:03 am »

While I appreciate all the testing and research you pixel peepers do, I have to just shrug and go shoot.  ;D

Sharon

Sharon, as in all things in life, there must be a balance.
I have images that I have taken where the light was perfect, the scene moved me spiritually and the camera took the shot.
Upon examination, the shot sucked but the visual at the time the shutter was clicked was magical.

I try to balance the "tool" I am using with what I consider to be just a wee bit more than adequate for the moment in time and price.

As I said before, the 500cm and Leaf 45+ was quite adequate and produced one of my very favorite image.

But being the Beast that I am, I had to just "stick my toes in the water" to see if there 100 would give me what I want in the manner I JUDGE the "tool" I want to use.

I am now going to define IF the GFX 50S, which I have already defined the 100 does not do it for ME, surpass the Hasselblad H4D 60 that I have on my desk.  I just bought a HC 28mm with less than 2K clicks on it and deliver is this afternoon.

Not a difficult task to guess where I will be at this afternoon - back shooting the pond that I tested the 50S against the 100!

In short, do you think if I was a watercolor painter I would be comfortable using brushes I got at Sherman Williams paint store, or would I sample what it at Blick?

I'm still sampling ....... and just having fun doing that.  Please don't take this thread too seriously, I'm not.
Just a learning and sharing tool in my mind.

Jack

PS:  Yes Jim, I know of Alvy and his work, but thanks for the reminder that he is "still out there!".  :-)
Logged
Jack

Jim Kasson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2281
    • The Last Word
Re: GX 100 returned as it could not match my GFX 50S
« Reply #86 on: January 09, 2020, 09:35:14 am »

Hi Jim,

I would define oversampling applying a sample frequency (pixel pitch) at more than twice of the sampled analogue bandwidth (the light from the lens projected on the sensor).
I would define undersampling applying a sample frequency at less than twice of the sampled analogue bandwidth.
The by you mentioned Nyquist frequency (Fs/2) is part of the digital domain, not the analogue domain.

Im sure you already knew this, right  ;)


I agree with your definitions of over and undersampling, which are the same as mine. The Nyquist frequency is a particular sampling frequency. Sampling frequencies are completely valid in the analog world (I prefer to reserve the word "domain" for something else). For example, if the highest spatial frequency in the input (analog) image is 0.2 cycles/um, then the Nyquist frequency is 0.4 cycles/um.

Jim

George_Cleansman

  • Newbie
  • *
  • Offline Offline
  • Posts: 11
Re: GX 100 returned as it could not match my GFX 50S
« Reply #87 on: January 10, 2020, 05:53:38 am »

I agree with what you're saying, except that I wouldn't call what's going on more oversampling. In fact, where artifacts show up it's because of undersampling. Increasing the sampling frequency by 40% reduces -- but does not eliminate -- the undersampling. Another way to eliminate it is to stop waaay down, but that has negative consequences as well.

I define oversampling as sampling at a higher frequency than the Nyquist frequency. I define undersampling as sampling at a lower frequency than the Nyquist frequency.

Jim


I'am sorry I am not so a high sophisticated expert like you Jim, but I understand what you like to point out. My experience is that when I get with 100 MP an technical advantage in that case of better scanning with more details in the image I also must accept a disadvantage of less f-stop with less DOF. Thats life.

George
Logged

Rob C

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 23311
Re: GX 100 returned as it could not match my GFX 50S
« Reply #88 on: January 10, 2020, 02:32:54 pm »


I'am sorry I am not so a high sophisticated expert like you Jim, but I understand what you like to point out. My experience is that when I get with 100 MP an technical advantage in that case of better scanning with more details in the image I also must accept a disadvantage of less f-stop with less DOF. Thats life.

George


Makes me smile when I think back to the 60s, and using 4x5 film, and stopping waaaay down...

Ironically, that was before I hung out my shingle, after which it was only 135 and 120 films, and the most I was inclined to stop down was to about f8. That was because of the nature of my work, and today's super 135 format digital cameras would have made larger formats not so important. I guess I could have lived my life at a pretty sweet f5.6 or f6.3 but that wouldn't have solved the problem of the 135 format being too tall for almost any of the vertical shots I had to make. A nice 36mm x 36mm format would have replaced both the formats I found myself using with a single camera system.

Perhaps, for young photographers, that may happen one day.

ErikKaffehr

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 11274
    • Echophoto
Re: GX 100 returned as it could not match my GFX 50S
« Reply #89 on: January 11, 2020, 04:23:54 am »

FYI:
I have been shooting the GFX 50S since it came out primarily with their 23mm and the 32-64.
Landscapes as only topic.

Purchased the GFX 100 from Adorama just before Xmas and finally had some time this
week to do some critical testing against the 50S for landscapes.

Was looking forward to it improving my results after all of the "test reviews" I've read about it.

Ran my own tests of a landscape scene with the 100 against the 50S.
Tripod, same lens, identical SS and A on both cameras.
2 Second timer used.
All shot in RAW with the GFX 100 at 16 bits.

Shot of couple dozen identical frames on each of three different scenes.

MY conclusion:  I shipped back the GFX 100 yesterday.

Reason: 
1.)  I saw NO improvement in Dmax, none!  Also NO improvement of banding if I push the sliders too far trying to pull back skies.
2.)  The GFX 100 was not as sharp at 100% as the 50S.  Actually quite a difference.

Now, don't want to start a "Range War" here, just saying to be sure to run some serious real world test before you let the return period expire.  That's all. 

Not what I wanted, but not a big surprise either when you think about it.  Jamming 102MP on the same size silicon as the 50S has got to give somewhere.

Hi,

Two observations and a half...


  • The first one is that if you view a 100 MP image at 100% magnification and a 50 MP image at 100% magnification the 100 MP image is viewed at 41% higher magnification.
  • The GFX 50S/R has undersize microlenses. So, the pixel aperture is approximately the same size on both the 50S and the GFX 100. So sharpness, which is decided by pixel aperture may be the same.
  • I don't really expected that DR would be higher on the GFX 100, except when dual gain conversion kicks in. Developement in DR is pretty slow.
  • To that comes diffraction. Stopping down beyond say f/11 diffraction may be the main limit on sharpness.

Best regards
Erik

Logged
Erik Kaffehr
 

ErikKaffehr

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 11274
    • Echophoto
Re: GX 100 returned as it could not match my GFX 50S
« Reply #90 on: January 11, 2020, 04:36:47 am »

Jim, I'm ancient in the world of digital so my age is showing!  LOL!
Guess I need to update my language skills to how Dmax is expressed today.

I used to develop software on the super computers Cray/SGI platform for 12 years before I dropped out at 46 to continue my own studies.
Put together a small team of kids out of MIT and GA Tech as a SGI Power Series VAR and developer.

That took me into working in many areas of digital, initially 3D realms, but lead me into a relationship with Eikonix when it was embryo and building it's first digital camera.  We expressed Dmax as the maximum spread of visual that could be distinguished from the Eikonix array. 

I then worked with "Leaf" in developing drivers for the Leaf 45 scanner, and later to the Howtek HiResolve 8K drum scanner, Nikon and Hasselblad's (very short relationship with Hassie as they suffered from NIH syndrome - not invented here) first digital cameras.

We always expressed how many stops of dynamic range we could "pull out of an array" as "Dmax".  It's just the number of stops of range from maximum distinguishable white to black.  When we passed a Dmax of 7 (7stops) I got rid of all my film gear and went totally digital with a P45+ mounted on a 500cm and 100 T* lens on the nose.  It took the P45+ back at 39MP to beat anything I could pull out of film and get a decent scan on my Howtek 8K scanner - I had my own Wing Linch processor and developed routines to really pull the film to give me what I wanted. 

Have never gone back to film.

So, what term should I update my "little gray cells" to use to represent what I call Dmax?

PS:  Eikonix was purchased by Kodak in an attempt to keep film alive and kill digital.  (At the time of the buy out, Eikonix was headed by a very bright chap named George Helms that I respected.)  It worked for a while but ..........

Hi,

I don't think DMAX is correct for sensors. DMAX is essentially maximum absortption. So Velvia that has a DMAX around 4 absorbs about 99.99 of the light. A photographic paper with D-MAx of 2.3 absorbs 99.5 % of the light.

With sensors we have Full Well Capacity (FWC), that is how many electron charges a pixel can hold. We also have a readout noise. Essentially the standard of deviation of the output of the sensor after a dark exposure.

FWC divided by readout noise gives the dynamic range, DR. DR is a measure how dark an image still holds some detail.

These posting provides some hands on demos: https://www.dpreview.com/forums/post/58984278

Best regards
Erik
Logged
Erik Kaffehr
 

Lust4Life

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 705
    • http://www.shadowsdancing.com
Re: GX 100 returned as it could not match my GFX 50S
« Reply #91 on: January 12, 2020, 08:31:02 am »

Erik,

Good to see you are still vertical and haunting the threads here!

Yes, Dmax as I used it in my post is not valid today, as I mentioned earlier in a reply to Jim, just a habit of mine.

In the realm of digital, my little gray cells go back to 1980 to 82 or so, and Dmax is what we called the "maximum density range" we could pull out of an array (now called a sensor, as you just used).  We didn't know what we were talking about as we had no foundation of a historical language in a digital imaging sense.

One area of the cameras hoped for market was archival of fine art in digital format at the museum level.  I spent some time on that sector, it went no where.  The push back was strong as the insight of that market had no foundation to what it could do and was very conservative.

But it was a fun time and experience.  As I remember, the camera was EXTREMELY sensitive to any fluctuations in the electrical source you plugged it into which present major problems in getting consistent results!  But that was eventually overcome. 

As I sit here with the GFX 50S and the H4D 60 on the corner of my desk, this thread has brought back many memories of fun times experimenting with the Eikonix.   

PS:  I was never able to find a buyer in my market for it, most thought it was a gimmick and could not see the future.  But Nikon became aggressive in producing their first unit and the rest is history.

PPS:  For anyone wondering just WHO started the Mega Pixel Race, this site has an interesting video of the "Inventor":
https://www.diyphotography.net/worlds-first-digital-camera-introduced-man-invented/

And this site:
http://www.cameramuseum.ch/en/N5902/.html

And this is were we are NOW:
https://youtu.be/b8dsssSi4Aw

(For the purist, this thread had drifted a long way from my decision to keep my GFX 50S and send back the GFX 100.  I'm partly responsible for the "drift" off topic - sorry about that!  I'm sticking to my decision of dumping the GFX 100 BUT I admit I have go wonder IF I had a poor sample....... doubt it.)





« Last Edit: January 12, 2020, 10:31:56 am by Lust4Life »
Logged
Jack

ErikKaffehr

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 11274
    • Echophoto
Re: GX 100 returned as it could not match my GFX 50S
« Reply #92 on: January 13, 2020, 12:13:09 am »

I just did icuts of the screen for each of the camera for anyone that wants to see what I experience between the 50S and the 100.

Sharpening was stopped at the point going any further only degraded the respective images.

Capture One v. 20 used for both.  Both zoomed in 300% in C1 before icut was done.

Jack

Hi Jack,

I took your GFX 100 image, downsized to 71% in Photoshop and copy pasted parts of the GFX 100 image into the GFX 50 image. See attachement.

My first guess was that there may be something wrong with your GFX 100. Now, I don't think so.

Best regards
Erik
Logged
Erik Kaffehr
 

Martin Kristiansen

  • Sr. Member
  • ****
  • Online Online
  • Posts: 1392
    • Martin Kristiansen
Re: GX 100 returned as it could not match my GFX 50S
« Reply #93 on: January 13, 2020, 12:38:54 am »

The pasted in pieces are head and shoulders above the background image. Im surprised at how big a difference I see
Logged
Commercial photography is 10% inspiration and 90% moving furniture around.

Lust4Life

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 705
    • http://www.shadowsdancing.com
Re: GX 100 returned as it could not match my GFX 50S
« Reply #94 on: January 13, 2020, 06:27:12 am »

Erik,

I agree when you go in only 70% with the GFX 100 and yet 100% with the GFX 50S.
Why those particular ratios did you choose to use to evaluate the respective cameras?
Based on the 100 pitch being .7 compared to the 50S per Jim's comment back on page one?
« Last Edit: January 13, 2020, 06:33:29 am by Lust4Life »
Logged
Jack

ErikKaffehr

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 11274
    • Echophoto
Re: GX 100 returned as it could not match my GFX 50S
« Reply #95 on: January 13, 2020, 06:52:25 am »

Hi Jack,

100MP / 50MP -> 2

sqrt(2) -> 1.41

100% / 1.41 -> 71%

So, downscaling a 100 MP image to 50 MP needs rescaling to 71%. That will deliver approximately the same feature size as the 100% sized 50 MP image.

Best regards
Erik

Erik,

I agree when you go in only 70% with the GFX 100 and yet 100% with the GFX 50S.
Why those particular ratios did you choose to use to evaluate the respective cameras?
Based on the 100 pitch being .7 compared to the 50S per Jim's comment back on page one?
Logged
Erik Kaffehr
 

macfly

  • Newbie
  • *
  • Offline Offline
  • Posts: 9
    • Andrew Macpherson
Re: GX 100 returned as it could not match my GFX 50S
« Reply #96 on: January 15, 2020, 02:55:12 pm »

So the GFX100 is the clear winner here. This whole thread wasn't making sense to me, and finally in seeing this I'm left scratching my head?

Logged
Andrew Macpherson

LA CA USA

Jim Kasson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2281
    • The Last Word
Re: GX 100 returned as it could not match my GFX 50S
« Reply #97 on: January 15, 2020, 03:15:16 pm »

So the GFX100 is the clear winner here. This whole thread wasn't making sense to me, and finally in seeing this I'm left scratching my head?

It's explained on the first page of this thread. Sharpness isn't much difference, but aliasing sure is.

Jim

Christopher

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1491
    • http://www.hauser-photoart.com
Re: GX 100 returned as it could not match my GFX 50S
« Reply #98 on: January 16, 2020, 03:16:35 pm »

As I said countless times before the GFX100 is absolutely amazing I would never ever consider going back to my 50s.
Logged
Christopher Hauser
[email=chris@hauser-p
Pages: 1 ... 3 4 [5]   Go Up