Michael's Pentax 645z Review

[michael]

Hello Michael,

While buying a 645z is way out of my league, I read your review with great interest. Having used various film and digital Pentaxes for the last 9 years, I was curious about how their (generally) excellent handling was transcribed in the MF digital era. Seems like they did it right again!

Well, anyway, I wrote here to comment on your ETTR remark. Having dabbled a little bit with that technique on their K DSLR line, the obvious setback that everyone quickly encounters is indeed the histogram being based on the JPG...

But (don't know if you stumbled on this on your investigation about the matter) there is a mean to get a near-real RAW histogram on the Pentaxes by using the UniWB trick!

Steps are easy:
- go to M mode, be sure to completely overexpose a picture (completely white pic).
- go to the white balance settings, custom WB, and use the shutter to snap a (fully white!) WB reference pic.
- go to the image settings, chose "muted" and customize it with low contrast and a slightly brighter setting (you can even use the advanced contrast setting to fine-tune the highlights and shadow contrasts).

By following these steps, the camera will be tricked by the custom WB and will apply a 1-1-1 ratio on the bayer matrix, instead of pushing up the reds and blues to balance with the doubled green photosites.

I voluntarily left out the exact image settings (contrast, brightness, etc), as it greatly depends on the sensor used. You have to play with them and compare resulting on-camera histograms with the actual RAW histogram (from Rawnalyze for instance)...

Only drawback : any JPG preview you get from the camera will be greenish and washed out, so forget about OOC JPGs...
But an easy way out of this is to assign these settings to a User custom mode only, so this way the camera will behave as usual in every mode except for this "UniWB" User mode...

Hope this helps...

Interesting suggestion, but there's an easier way.

Use the red blinkies in Live View. As I mentioned in the review, they perfectly show highlight clipping that matches LR and RD histograms.

Even if one is shooting with the viewfinder, just popping into LV for a moment to confirm optimum exposure is all it takes.

Michael

[torger]

Could be worth noting that the smaller color gamut of sRGB and AdobeRGB is typically not the main problem for JPEG histogram inaccuracies. It's only a problem when highlight colors are saturated, and highlights is most often not so saturated. Oh well, if you photograph colorful flowers the smaller gamuts are a problem. But otherwise the main source of inaccuracy is instead the difference in white balance. The cameras generally see white as green, while the white balance is set to render white as white, and this is what the UniWB trick is intended to correct.

I've tried the UniWB trick on my Canon, and indeed it works, but I've also found that by getting a feeling for how the camera renders JPEGs one can expose well anyway so I don't use it any longer.

The true raw clipping indicators in liveview on the 645z sounds like a really nice feature though for the the tripod-mounted landscape shot, so one can decide the exposure directly without having to make a test shot.

[dlacoutu]

Hummmm, it's strange that the liveview blinkies behaves differently from the Pentax K line, as the 645z innards are quite similar (if not identical) to the K3.

From experience, they are still taken from the "on-the-fly" conversion done by the Liveview (as it still reflects your WB and image settings), and thus do not reflect the actual RAW data.
And they only show brightness clipping, individual channels  clipping are not shown (from memory, so take with a pinch of salt).

A simple test would be using vastly different WBs (say, tungsten and shadow), and note their effect (or lack thereof!) on the liveview red blinkies... But I bet you'll get different results.

[michael]

Possibly.

But I use Daylight WB 90% of the time, and that matches nicely.

Frankly, I'm a pragmatist, and while I have a technical bent, my primary interest is in producing images, not playing with settings (appearances to the contrary).

When I find that something works well for me, I simply use it, and leave the theoretical and marginal case stuff to those that enjoy experimenting and have the time to do so.

Michael

[John Nollendorfs]

Michael:
When you go to that meeting with the Pentax folk, could you ask them if they are considering a new "mirror-box-less" design? It seems to me, such a revolutionary medium format design concept would make a lot of sense.
--much smaller, lighter camera.
--less chance of mechanical failure (6x7 Pentax was great for that!)
--no mirror slap to dampen leading to sharper images
--much quieter
--cheaper? ;-)

[ecarmel]

Hi Michael thanks for the informative review and for your real world use observations. I have also used the D800E and Hasselblad H5D50 cameras and sold both after getting the 645Z, for many of the reasons you mention. First and foremost the high iso / image quality combo can't be beat for landscape work - it is so nice to not be a victim of the wind anymore, especially during wildflower season. I have a few things I am wondering about the camera: I have turned on the diffraction correction feature that is provided and still feel that diffraction is occurring noticeably at f22 - I am shooting mostly at f16 to avoid this and still get DOF. I do find I need to focus stack on some shots to get everything in focus. What are your thoughts on the diffraction correction feature and smaller apertures on this camera? Maybe worth a discussion with them at photokina since I can't find any info online about it.  Also I am wondering if iso 200 is the base iso of this camera and not iso 100, in the interest of getting every last grain of quality from the files. On some tests I ran it seemed that iso 200 looked better than iso 100. Also have you done any tests on shutter shake and determined that there are certain shutter speeds to avoid when doing tripod mounted / mirror up shooting? This was not an issue with the Hasselblad leaf shutter lenses but feel it needs to be looked at with this camera.

I am currently preparing an online review for my blog of the 645z and will share a link here when complete.

Elizabeth Carmel
https://www.elizabethcarmel.com

[ErikKaffehr]

Hi Michael,

A good review, thanks very much! I hope Pentax sells lots of them!

Best regards
Erik

We have just published my in-depth Pentax 645z review.

I have started this thread as a place for discussion about the review and as a place where I can answer any questions.

Michael

[ronniemac]

We have just published my in-depth Pentax 645z review.

I have started this thread as a place for discussion about the review and as a place where I can answer any questions.

Michael

Of the many camera reviews I have read (and watched), this is by a long way, the most engaging, informative and useful I have had the pleasure to read.  What is particularly reassuring is that you liked it enough to buy it, and that you retracted a comment you made in your first impressions review.  It takes a big man to do that!

Clearly it is the review of an experienced landscape photographer, rather than a salesman or lab technician (absolutely no disrespect intended to these two parties who do fulfill a valuable role!).  Your review tells us what it is like to use the 645z and it clearly implies that you enjoy the experience of and results from this camera.

I'm still using film for MF (Pentax 645 N), but hopefully one day I'll make the jump to Z - got plenty of good lenses in waiting. 

Really enjoyed your review, Michael, thank you for writing and sharing it.

p.s. I also did enjoy your video "The Mirrorless Revolution" which addresses the other end of photography when a quick lightweight quality camera is needed. (If only Pentax would bring out a ff mirrorless!)

[bcooter]

When someone talks to Pentax, ask them about their tethering suite, time of delivery, will it process or just shuttle?

Shuttle is fine as long as it's quick, but until it tethers it'll be DOA on most professional sets.

IMO

BC

[eronald]

I think RED is going to be the next new entrant in the still photo field.

Exciting times.

Edmund

[Ken R]

I think RED is going to be the next new entrant in the still photo field.

Exciting times.

Edmund

They have tried to push their current camera for stills for years but even the current Red Dragon sensor, while awesome, is still too wide aspect (30.7mm x 15.8mm) and too small to compete with the look of the larger formats (although very fast lenses help). The camera also is made to be used with the sensor horizontal and even though RED sells a nice grip w/ battery and EVF the camera needs to be rigged up quite a bit for most uses. Also, I believe flash sync is limited to 1/60 due to the electronic shutter (if it works). RED definitely has the capability to make an amazing stills camera but I do not know if they want to.

I have used the RED One Mx and EPIC Dragon so I have some first hand knowledge of the cameras but I am sure DC or someone else can provide more info.

Regarding the 645z (back on topic ) I would love for Pentax/Ricoh to provide MUCH faster and better service (that is the  main reason I let go of the 645D) and also would love to see a wider range of lenses and with better build and feel to at least match the camera body which is very nice. A 19mm rectilinear super wide angle would be awesome for Architecture interiors and also a 28mm Tilt/ Shift with 82mm filter thread. A 100mm f2 lens would be awesome also.

[michael]

I think RED is going to be the next new entrant in the still photo field.

Exciting times.

Edmund

A Pils at Koln during Photokina says they won't.

Michael

[torger]

Michael,

if a Phase One system with IQ250 and corresponding lens lineup would cost the same or even a bit less, would you still prefer the Pentax?

When I read your review it seems to me that the Pentax 645z is the current best match for your shooting style (taking the print-making into account too) even if we drop the cost factor.

I'm struck with how much the shooting style is integrated into the camera choice, and of course it should be like that. It's sometimes easy to forget, especially in medium format land where image quality often seems to be number 1, 2 and 3, forgetting about how useful the system is to make pictures with the shooting style one prefer.

[JV]

Michael,

One question I have been wanting to ask and I hope you don't take offense in me asking it.

In the past and up till very recently you have been very vocal about closed systems, especially with regards to Hasselblad.

Obviously the Pentax 645Z is a closed system system as well and in their case the back is (as far as I know) even non-removable.

Did you change your opinion in any way about closed systems? 

Thanks, Joris.

[michael]

There is a difference between a closed system that is closed because the manufacturer is afraid of losing component sales to the competition, and a product which is closed because it is a logical impossibility for it to be open. That's like complaining that a car isn't a boat.

In any event, Hasselblad recently announced that anyone can now buy a H5X (without a trade in) and so the system is open once again.

I wonder what the state of Hasselblad would be today if they hadn't closed the system some eight years ago. Would Phase still be top dog?

Michael

[deejjjaaaa]

Obviously the Pentax 645Z is a closed system system as well and in their case the back is (as far as I know) even non-removable.

645z is a dSLR with a big sensor...

[michael]

Michael,

if a Phase One system with IQ250 and corresponding lens lineup would cost the same or even a bit less, would you still prefer the Pentax?

When I read your review it seems to me that the Pentax 645z is the current best match for your shooting style (taking the print-making into account too) even if we drop the cost factor.

I'm struck with how much the shooting style is integrated into the camera choice, and of course it should be like that. It's sometimes easy to forget, especially in medium format land where image quality often seems to be number 1, 2 and 3, forgetting about how useful the system is to make pictures with the shooting style one prefer.

Well, that's obviously a hypothetical. If my grandmother had wings, she'd be an airplane.

But seriously, the answer is – probably not. My shooting needs have changed over the past few years.

Given money no object my choice right now would be a Leica S and all of their lenses first, with the Pentax system second. But I'd much rather eat for the next 5 years, so the Pentax is my real-world choice.

Photokina is now just 10 days away. Let's see what it brings.

Michael

[eronald]

Photokina is now just 10 days away. Let's see what it brings.

Michael

Jet engines for grandmother?
A larger Sony MF sensor and Phase and Hassy announcements?
The oft-promised digital Xpan?
A truly open Hasselblad body system compatible with all old Hassy and Phase backs?
Yet another Phamiya refresh?
A slew of MF compacts from Sony, Mamiya and Fuji ?
Decent software for the Sigma?
A cigarette-pack sized 4/3 camera with EVF?


Edmund

[JV]

In any event, Hasselblad recently announced that anyone can now buy a H5X (without a trade in) and so the system is open once again.

It is the H4X that is now available again without trade in.

There are Photokina rumors about a Hasselblad H5X:
http://photorumors.com/2014/09/03/new-photokina-rumor-hasselblad-to-open-their-h5-system-for-3rd-party-digital-backs/
but who knows…

If Leica could price its new CMOS S body around $15K I am convinced that they would take a lot of business away from Phase One and Hasselblad.

If they keep current prices (which I suspect they will or perhaps slightly lower at around $20K) then Pentax over time might become the main player…

That is if Sony or Fuji don't step in… It's all good and interesting!

[photodan]

(snipped from original message)... If my grandmother had wings, she'd be an airplane...
...Photokina is now just 10 days away. Let's see what it brings.
Michael

Huh? I would have thought if grandmother had wings she'd be an ... angel!.  I think Michael may be subconsciously thinking of a discounted way to do the Drake Passage airplane flyover :-)

Ok, maybe a poor attempt at humor.

However, if someone like Sony or Fuji announced a medium format mirrorless version of the Sony Rx1r or A7 series, or Fuji XT1 or digital version of a scaled down Fuji GW690, at a price point below the Pentax 645Z then I'd sure be flying high!