Greetings - 645z owner

[gavincato]

Hi guys

Just saying hello. I'm a new 645z owner. Was searching for medium format forums and found here.

I wrote up a review of the 645z here ;

http://www.gavincato.com.au/the-pentax-645z-a-wedding-photographers-medium-format-dream/

And am having good results using the lovely hasselblad 110mm f/2 on it for weddings/portraits.

cheers

Gav

[flashfredrikson]

Great write up on your blog Gav, thanks for that!

I am considering the 645z myself right now. I own and use a Hasselblad H5d 40 but would like to get the new sensor and the upgrade for my blad would be more than the Pentax with two or three lenses!
Do you ever use tethering with the Pentax? If so, does it work well? I heard mixed things... Tethering is sort of important for me shooting fashion with clients and crew on set...

thanks,
martin

[voidshatter]

The dynamic range mania 

[JohnBrew]

Excellent review and the images are all top notch. Pentax should thank you.

[gavincato]

Hi martin - I've never tried shooting it tethered - I haven't been in a studio for years. Just an outdoor shooter mostly

[Hans Kruse]

Once again the medium format myth: The depth of field is beautiful. On smaller sensor systems the DoF drops off near instantly when using fast aperture tele lenses. On medium format you just get this beautiful roll off to the out of focus regions. I just can’t get enough of this look. I don’t say this to disparage 35mm based systems – Canon & Nikon both make some absolutely beautiful glass. But the way the medium format looks is just more what I am after when shooting people.

There was a recent discussion on this and as I remember it the DOF drop off was dismissed as not existing like it was said in the above statement. It probably comes down to placebo and the differences between lens designs....

[NancyP]

There's only one plane that is maximally "in focus" - all the others have larger circles of confusion. Enough for theory. Question is, how big can a COC get before it is deemed "out of focus". The practical definition of DOF depends on degree of magnification to final size print, viewing distance, etc, as well as the usually specified field of view, focal length, aperture.

So, Hans and others, you could be entirely correct, or, just plain wrong, depending on the specific conditions of the comparison. I suppose that the real question is, does the depth of field "roll off" (whatever that means - presumably the increase in COC in planes close to the in-focus plane) matter under your particular viewing conditions.

https://en.wikipedia.org/wiki/Depth_of_field

[Hans Kruse]

There's only one plane that is maximally "in focus" - all the others have larger circles of confusion. Enough for theory. Question is, how big can a COC get before it is deemed "out of focus". The practical definition of DOF depends on degree of magnification to final size print, viewing distance, etc, as well as the usually specified field of view, focal length, aperture.

So, Hans and others, you could be entirely correct, or, just plain wrong, depending on the specific conditions of the comparison. I suppose that the real question is, does the depth of field "roll off" (whatever that means - presumably the increase in COC in planes close to the in-focus plane) matter under your particular viewing conditions.

https://en.wikipedia.org/wiki/Depth_of_field

Yes, I'm sorry to say pretty basic, but you have not addressed the issue of differences due to different sensor size

[Hans Kruse]

There's only one plane that is maximally "in focus" - all the others have larger circles of confusion. Enough for theory. Question is, how big can a COC get before it is deemed "out of focus". The practical definition of DOF depends on degree of magnification to final size print, viewing distance, etc, as well as the usually specified field of view, focal length, aperture.

So, Hans and others, you could be entirely correct, or, just plain wrong, depending on the specific conditions of the comparison. I suppose that the real question is, does the depth of field "roll off" (whatever that means - presumably the increase in COC in planes close to the in-focus plane) matter under your particular viewing conditions.

https://en.wikipedia.org/wiki/Depth_of_field

There was a similar discussion on this thread http://forum.luminous-landscape.com/index.php?topic=100851.40
and at least one post regarding DOF rolloff.

[alatreille]

Hi Gavin,

Wonderful review, that mirrors much of my experience with the camera.
Though Architecture doesn't tend to move around as quickly as your subjects do.

Cheers

Andrew

Hi guys

Just saying hello. I'm a new 645z owner. Was searching for medium format forums and found here.

I wrote up a review of the 645z here ;

http://www.gavincato.com.au/the-pentax-645z-a-wedding-photographers-medium-format-dream/

And am having good results using the lovely hasselblad 110mm f/2 on it for weddings/portraits.

cheers

Gav

[gavincato]

Once again the medium format myth: The depth of field is beautiful. On smaller sensor systems the DoF drops off near instantly when using fast aperture tele lenses. On medium format you just get this beautiful roll off to the out of focus regions. I just can’t get enough of this look. I don’t say this to disparage 35mm based systems – Canon & Nikon both make some absolutely beautiful glass. But the way the medium format looks is just more what I am after when shooting people.

There was a recent discussion on this and as I remember it the DOF drop off was dismissed as not existing like it was said in the above statement. It probably comes down to placebo and the differences between lens designs....

Hi Hans,

Well I'm either crazy or seeing things. Even my wife who couldn't care less about camera gear noticed it and commented on it completely unprompted.

I have not done proper side by side tests but I have shot at a wedding at similar times with a canon 135/2 on a 1Dx then a few minutes later on the 645z with pentax 150/2.8 - the DoF rolloff, or whatever you want to call it looked a lot nicer to me on the 645z.

But I've noticed a "nicer" dof across most lenses even the humble 55mm.

[ErikKaffehr]

Hi,

I have shooting with a Hasselblad 555/ELD and a Sony Alpha 99 for something like two years. I have very few shots that are comparable, but I would say that I see very little difference whenever I shoot under comparable conditions. Let's say both cameras on tripod, Sony at f/8 and Hasselblad at f/11 same distance and same field of view, I see very little difference.

So, I would agree with Hans on this issue.

Just so you know, Hans was instructor on one of the Phase One workshops, so he had proper access to Phase One equipment. I would say that both Hans and I would acknowledge that the resolution advantage is there with MFDB, we just don't see the magic…

The Pentax 645 is a fine camera, with a state of the art sensor that is probably very similar to the one in the latest Niko, Sony and Pentax cameras. A larger sensor has some advantages, like less noise and higher MTF at a given feature size if all other things are constant, but that is more like physics than magics.

Best regards
Erik

Hi Hans,

Well I'm either crazy or seeing things. Even my wife who couldn't care less about camera gear noticed it and commented on it completely unprompted.

I have not done proper side by side tests but I have shot at a wedding at similar times with a canon 135/2 on a 1Dx then a few minutes later on the 645z with pentax 150/2.8 - the DoF rolloff, or whatever you want to call it looked a lot nicer to me on the 645z.

But I've noticed a "nicer" dof across most lenses even the humble 55mm.

[yashima]

Beautiful work Gavin.

Could I pls ask what is your post workflow to add the sunlight flare across the whole images like this, really beautiful:

http://www.gavincato.com.au/wp-content/uploads/2015/06/09-4000-page/sam-erin-wedding0031.jpg

Ya

[Telecaster]

There's a gentle rendering character to many Pentax lenses that in my experience works well with higher resolution films & sensors. The 77/1.8 Ltd. is a favorite of mine on Sony's A7r for this reason. The A series 100/2.8 is another. In the 645 range the 75 & 150mm f/2.8s, in particular, have this character. They provide enough spatial resolution (for me anyway) without any hard/harsh qualities.

-Dave-

[gavincato]

Hi Erik - I do doubt that at small apertures you could see a difference but personally I see a difference at wide apertures - as a wedding guy I generally shoot at fairly fast apertures.

If I didn't see a difference i would stick with my canon gear

Having said that this is the first medium format I've owned. Maybe it is the lenses? All I know is I'm liking the results a lot better then on my fast canon lenses.

Cheers

[gavincato]

Hi there - that's just the beautiful way the 110mm handles flare, it's great.

Beautiful work Gavin.

Could I pls ask what is your post workflow to add the sunlight flare across the whole images like this, really beautiful:

http://www.gavincato.com.au/wp-content/uploads/2015/06/09-4000-page/sam-erin-wedding0031.jpg

Ya

[ErikKaffehr]

Hi Gavin,

Good point! You are right that I am mostly shooting medium apertures, both on the Sony and the Blad.

Best regards
Erik

Hi Erik - I do doubt that at small apertures you could see a difference but personally I see a difference at wide apertures - as a wedding guy I generally shoot at fairly fast apertures.

If I didn't see a difference i would stick with my canon gear

Having said that this is the first medium format I've owned. Maybe it is the lenses? All I know is I'm liking the results a lot better then on my fast canon lenses.

Cheers

[Hans Kruse]

Hi Hans,

Well I'm either crazy or seeing things. Even my wife who couldn't care less about camera gear noticed it and commented on it completely unprompted.

I have not done proper side by side tests but I have shot at a wedding at similar times with a canon 135/2 on a 1Dx then a few minutes later on the 645z with pentax 150/2.8 - the DoF rolloff, or whatever you want to call it looked a lot nicer to me on the 645z.

But I've noticed a "nicer" dof across most lenses even the humble 55mm.

I'm not doubting what you see. Most likely there are several things at play here: The different rendering of the high resolution 645Z sensor relative to the low resolution 1Dx and the lenses that are different. It would be interesting for you to try the new Canon 5Ds in a similar setting with the Canon lenses and to test it against the 645Z. I'm sure it would still look different but I think that you would find the 5Ds quite different from the 1Dx. I haven't tried the 5Ds yet, but the differences in rendering from the Phase One IQ160, the Nikon D800E and D810 and the Canon 5D mkIII and 1Ds III were all quite visible. In addition the different lenses I have had for the Canons and Nikons all rendered differently. So what exactly makes the difference is in my opinion a lot of factors and not just the sensor size. I may be wrong, but then so be it

[Ken R]

I'm not doubting what you see. Most likely there are several things at play here: The different rendering of the high resolution 645Z sensor relative to the low resolution 1Dx and the lenses that are different. It would be interesting for you to try the new Canon 5Ds in a similar setting with the Canon lenses and to test it against the 645Z. I'm sure it would still look different but I think that you would find the 5Ds quite different from the 1Dx. I haven't tried the 5Ds yet, but the differences in rendering from the Phase One IQ160, the Nikon D800E and D810 and the Canon 5D mkIII and 1Ds III were all quite visible. In addition the different lenses I have had for the Canons and Nikons all rendered differently. So what exactly makes the difference is in my opinion a lot of factors and not just the sensor size. I may be wrong, but then so be it

Yea.

The thing is no camera or lens work by themselves. The image is a result of the filters>lens>camera/sensor>software/processing. On can isolate each component and evaluate but ultimately one works with a set of components to make an image. The are thousands of possible combinations but some are only possible with certain systems. (you can't process native 645z raw files using C1Pro for example or use leica lenses on the 645z)

[gavincato]

Very true guys. Thanks for the interesting read