Michael's Pentax 645z Review

[Ken R]

Hi, here is a quick Dynamic Range test by Mahesh / http://starvingphotographer.com using the 645z.

http://starvingphotographer.com/pentax-645z-real-world-dynamic-range/

He underexposed severely to save highlight detail. Probably more than is required in this case but even so the result is impressive. On a side note, the Pentax 25mm lens seems to be lacking a bit in sharpness (specially close to the borders) and has noticeable CA and some distortions. I found that I needed to sharpen the file a heck of a lot more than my IQ160 files but the end result in the resolution department is good. The file felt a LOT like a tad larger D800E file but with an average lens.

Maybe Michael can chime in and expand on this.

[michael]

I guess I don't understand what he means when he says that he "underexposed by two stops". Underexposed from what, based on what?

There is only one proper exposure to maximize DR, and that's ETTR.  Since the 645z has real-time exposure warning in Live View that almost exactly matches Lightroom's raw histogram readings, it should be simple to do an optimally exposed shot.

In the end though, I agree with him. The 645z's DR is among the best I've ever seen.

Michael

[deejjjaaaa]

I guess I don't understand what he means when he says that he "underexposed by two stops". Underexposed from what, based on what?

based on the content of the scene

let us use FRV ( http://www.fastrawviewer.com/ ) and simulate what will be if we are to add 1 stop more to exposure



so he was trying to protect quite useless highlights in those areas, those might be painted by ACR/LR algorithms quite nicely... red (magenta actually) = clipping in 1 channel, blue = clipping in 2 channels, black = in 3 channels

and what if we add 2 more stops = still pretty much not a problem



using LR or ACR to evaluate clipping ? gimme a break !

[pedro39photo]

amazing what those 35mm and MF exmor sony sensors can capture, the bar its very high for all the next brand sensors.

[Theodoros]

Word.

Bottom line on the Pentax is this.

If you work in commerce and your shooting 6 figure projects 9.999 times out of 10 you'll use a phase or a leaf if the job requires medium format.

Pentax played their hand with the  D having virtually no tethering, a tiny buffer  and no immediate solution for any professional processing suite.

Now with the Z, tethering is in the future, professional support isn't mentioned.

For some that's fine, for me that's not.

I hear Pentax will do this, will do that, set up this, offer that, but that's not today and today most of us are working for a living.

And BTW::  Having a good dealer for Leaf and Phase doesn't mean the products are faulty or lack maturity, it just means you have a true professional to assist you and all of us or only as good as who we work with.

EVERY camera company has had issues.  Even deep pockets Nikon, Canon and Sony have pushed stuff out too soon.

Example:   (One of many)

Steve Hendrix has helped me source equipment at 9pm  at night.  When I bought my S2 from him, I got goofy and tried to put an old tilt shift on the contax adapter (bad move) the night before the shoot.  It jammed and I called Steve who was on his roof clearing his gutters.

The next day I had a new adapter.   That's the service professionals need.

I own broncolor HMI's, the blue ones.   Nobody has them, nobody in the U.S. knows anything about them.  If I want a part, a fix, another one . . . Steve finds it.  So yea, a good dealer is priceless and when it comes time for me to buy a new medium format anything, Steve is first on my list,
second would be Doug and Lance.

I just wish CI sold motion equipment because they'd get all of my business.

I'll tell you I don't understand why everyone loses their mind over the price of professional cameras, especially medium format.  Phase/Leaf/Hasselblad/Leica don't have supenoa power, they just offer a product and it's up to the buyer to make the decision.

If you think there price is too high, don't buy.  If you're mad that they won't sell you a $26,000 camera for 8 grand, go a different direction.  There is more to costs than upfront.

My ancient Phase backs are still very viable, produce a unique look and the service I get from Capture Integration is the same today as it was when my backs were new, the software is improved every year.

That's a professional requirement that has made me money for a lot of years and I have no worries using it today, or tomorrow and btw:   my phase backs have never had one single service.  Not even a loose screw.   With Leaf I loved the look, some of the best work in my life with their backs, the ONLY issue was way back then with their software which they fixed a billion years ago.  Yair is one of the most honest and stand up guys on the planet and will go to extraordinary lengths to save your ass.

So for anyone to get mad at the dealer system is just damn silly.  These a pros that should be rewarded for their efforts and none I know are driving 911's or moving into 5,000 sq. ft. beach houses in Malibu.

_____________________

Now in regards to my comments on RED, I don't care who uses an Arri.  I know a lot of operators and dps that prefer Arri, none (absolutely none I know) own one as the production company sets the budget and arranges for the equipment.  Most DP's own a dslr or a small black magic pocket cam for fun.
 
Though the dps I know that don't like RED uses them when their shooting on their own money, so it can't be that bad.

Me, I hate renting,  I buy.  

My RED's (two R1's and the Scarlet) work reliably and professionally,  make me money and have never had a repair after going around the world multiple times.  I've had one break on a Rocket Card and one EVF had some issues, other than that their bulletproof and my RED rep helps me whether I'm in our London, Dallas or LA facility.

Maybe Arri does also, I'll probably never know because an Alexa is 80 grand my reds were about 24k a body and the Alexa weighs twice what the RED's do, so for my style of work, the Alexa is too big.

And though I work around the world, use equipment from every company, I'm kind of proud that the RED's are made in America.  No other pro camera is.

Also I never said RED made a still camera to equal medium format, or even a mid range dslr, but I did say they make cameras for the new media world where motion and still content come together in an electronic pallet.  But honestly if the "special frame" is more compelling from the motion grab than the still shot a client will always pick the most compelling image.  

_____________________

We have an upcoming print ad that we co op with another company that will run in CA.  Today I'm doing concepts,   This is my studio's money, the media buy is as much as a Pentax the production costs even more and I know I'll probably shoot it with my ancient Phase backs.

Since this is my face to the world and probably the most important imagery we produce I could use anything.


IMO

BC

P.S.  And for a disclaimer, nobody gives me anything for free.  I don't ask because knowledgeable people and companies should be compensated for their services.

Do you expect anybody to read all this just to reply or quote on it on a forum? 

[Theodoros]

I guess I don't understand what he means when he says that he "underexposed by two stops". Underexposed from what, based on what?

There is only one proper exposure to maximize DR, and that's ETTR.  Since the 645z has real-time exposure warning in Live View that almost exactly matches Lightroom's raw histogram readings, it should be simple to do an optimally exposed shot.

In the end though, I agree with him. The 645z's DR is among the best I've ever seen.

Michael

He obviously considers not the maximum DR, but to protect HLs to the maximum because he considers extra LL information to be useless in the scene... I also do that in some cases, it's a matter of choice on what one thinks as most important on a scene... ETTR, may give max DR, but it also means that in certain scenes one may get HLs blown just to have useless information (to his judgement) present in LLs...  In such a case, one may consider to ignore the extra info in LLs, just to protect HLs as much as possible. ETTR is a technical matter, photography is ...a photographer's matter.

[bcooter]

Do you expect

I expect Peace, Love and my own aqua blue Gulfstream.

Maybe my expectations are too high.

IMO

BC

[Theodoros]

I expect Peace, Love and my own aqua blue Gulfstream.

Maybe my expectations are too high.

IMO

BC

Your peace, love, or Aqua blue gulfstream, are not mentioned in the post that I quoted.... (see? ....you made me read it!  )

[ErikKaffehr]

BC,

You are optimistic on the Peace part. The other two I guess you either already have or may achieve.

Thanks for posting anyway! Yes, your writing may be a bit on the long side, but it is good information from someone who has been there and done that. I really enjoy your posting!

Best regards
Erik

I expect Peace, Love and my own aqua blue Gulfstream.

Maybe my expectations are too high.

IMO

BC

[peterv]

Do you expect anybody to read all this just to reply or quote on it on a forum? 

I, for one, really enjoy BC's posts. I find it very interesting to read his opinions and I learn a lot from him.

[MrSmith]

 I can relate to those (BC's posts) more than the all the handwringing, angst and aggressive fanboyism.

[studio347]

I think commercial pros' point of view is very important since they appreciate the high efficiency of the camera system because of the high demanding shooting condition. But at the same time, commercial-pros view is not necessarily more important than non commercial-pros view.
I assume that in this forum, each group should maintain relatively similar importance.
I think it's an important aspect to have almost highest IQ without spending too much money with this new system.

I'm wondering the quality of Pentax lenses compared with Hassel HCs especially 120mm macro which I understand relatively well.
Without understanding the available lenses, the final IQ is difficult to tell, I guess.

[ndevlin]

I expect Peace, Love and my own aqua blue Gulfstream.

Maybe my expectations are too high.

IMO

BC

Maybe 'cause you don't use the word "Nyquist" enough in your posts. 

[MrSmith]

Nyquist?  Are they a grunge rock band from Seattle?

[LKaven]

Nyquist?  Are they a grunge rock band from Seattle?

Either that or a nighttime liquid cold remedy.

[Theodoros]

I, for one, really enjoy BC's posts. I find it very interesting to read his opinions and I learn a lot from him.

Me too, It was a joke about the size of it! 

[ErikKaffehr]

Hi,

Thanks for making that clear :-)

Best regards
Erik

Me too, It was a joke about the size of it! 

[eronald]

Fastrawviewer seems a wonderful aid for such discussions. However, I disagree with your pov that highlights in those areas *in this image* are useless because they can be rebuilt, the human eye is extremely sensitive to slight hue changes close to "white" and you need to get these exactly right in an image, it makes all the difference for the perception of the sky and thus the ambience. I used to spend my time clicking around like crazy in the cloud edges to find the right white point for the rest of the image - the differences don't show up that much on a normal print, but if you enlarge to 44" the eye becomes really sensitive to sky tone variations especially for the highlit clouds. For a normal image, or viewed at small size btw, I would agree with you.

Who knows, maybe if we chant "Nyquist" or "ETTR" enough, peace will descend on the middle east, Ukraine and the location the artist now known as Cooter lives. Now, before the todler comes back and starts yelling, I am going to take myself out for coffee and a stare at the girls showing off their summer legs in the autumn sun, and I wish all ye merrymen a good day


Edmund

based on the content of the scene

let us use FRV ( http://www.fastrawviewer.com/ ) and simulate what will be if we are to add 1 stop more to exposure



so he was trying to protect quite useless highlights in those areas, those might be painted by ACR/LR algorithms quite nicely... red (magenta actually) = clipping in 1 channel, blue = clipping in 2 channels, black = in 3 channels

and what if we add 2 more stops = still pretty much not a problem



using LR or ACR to evaluate clipping ? gimme a break !

[deejjjaaaa]

Fastrawviewer seems a wonderful aid for such discussions. However, I disagree with your pov that highlights in those areas *in this image* are useless because they can be rebuilt, the human eye is extremely sensitive to slight hue changes close to "white" and you need to get these exactly right in an image, it makes all the difference for the perception of the sky and thus the ambience. I used to spend my time clicking around like crazy in the cloud edges to find the right white point for the rest of the image - the differences don't show up that much on a normal print, but if you enlarge to 44" the eye becomes really sensitive to sky tone variations especially for the highlit clouds. For a normal image, or viewed at small size btw, I would agree with you.

we can probably do an experiement - bracket, supply you with "underexposed" raw, collect your xmp and see what "overexposed" raw looks like... but just in case with untwisted profiles if we are talking about ACR/LR