Phase One DF+ Focus Performance

[lance_schad]

We have been receiving positive reviews from the clients that have taken delivery of their DF+ upgrades/new units from us.

In particular here is a quote from a large rental studio here in NYC that took delivery this week and is using it on a big job right now:

"The focus (on the DF+) is actually remarkably better, not only does it focus fast, but it has not trouble finding it.
There is no back and forth like on the H system."

Please keep a look out for a more detailed review that is being worked on.

Lance

[evgeny]

Which H? Version 3, version 2 or older? 

[lance_schad]

Just emailed him and he said:

"H2/H4X. The longer lenses on H have trouble finding the focus and can take forever to nail down"

Lance

[evgeny]

I cannot understand why testers compare the newest DF+ to an old H2 and special edition H4x (x for extended), which is made for users who want to upgrade their H1/H2/H2F to H4x camera with True Focus. You know that the H4x is not an equivalent of the H4D.

Why not compare the new DF+ with the new H5D, or at least with the previous H4D generation. It would be a more competent test, isn't it.

Regards
Evgeny

[Doug Peterson]

Most comparisons made by individuals/companies are going to be against what they know/use or are considering rather than based on what the most direct/generationally-similar comparison would be.

Since the H2 is far more prevalent in the rental markets we serve than the H4D is that would be the comparison we'd hear most often.

I absolutely 100% agree with you the more journalistically fair comparison would be to an H4D. The H5D is not yet shipping (AFAIK) but once it's shipping in volume that would be an equally direct comparison.

If anyone with an H4D would like to make an appointment to come to our office we'd gladly let them use a DF+ for them to make their own comparison and write freely about their experience. If you make the appointment on a slower day we can probably even walk around NYC together for a broader range of subject matter than the studio provides.

My personal 2 cents are that I'm surprised the improvement between the DF and DF+. When Phase One announced it they didn't make a big deal of the AF improvements so I was not expecting much, but it seems to me they've under stated it a bit. It's still not a Canon 1Dx or anything, don't get me wrong - you won't be shooting fast moving sports with it anytime soon. But it's pretty darn snappy with very little "searching".

[FredBGG]

......

It's still not a Canon 1Dx or anything, don't get me wrong - you won't be shooting fast moving sports with it anytime soon.
.......

But it's pretty darn snappy with very little "searching".
........

It would be nice to have a MF camera with focusing as good as a Canon Rebel   The Pentax 645D would be the closest..... but still no on sensor AF.

"Pretty darn snappy"....

How does it really compare with the DF? A side by side video would be interesting.

However speed is not the only issue.

Only three centered focus points that are also not well defined are a significant limitation for any wide open use without the target of what
you want focused being in the center of the composition.
Adding more speed isn't going to solve this issue.
Lets say you are doing a full length shot from head to toe whit the model leaning forward.
You point the center focusing point at the models eyes. When you recompose to shot the focus moves to the ears.
Pretty much makes AF for shooting wide open far form adequate.
Rather unfortunate that this has not been addressed when MF is often touted for it's shallow depth of field look.

I find that not adding more focus points is a real limiting factor.

Adding more speed isn't going to solve this issue.

[bcooter]

Maybe it's all personal taste, but I don't have many issues focusing my Contax, either auto or manual and do a lot of focus then recompose.

With autofocus the Contax is slow but still usable though not near as good as the DF or the Blad.  With the contax I can manuall focus well, which I find more difficult with the DF.

The thing I hate about multiple focus points in 35mm, is in horizontal mode they really don't cover the whole 35mm frame so your always doing some form of focus, recompose, or your tempted (too tempted) to compose where the focus point reaches, which really isn't the best way to frame a photograph.

I assume that someday we'll have phase detect focusing where we push on a screen and that area will snap into focus and track but today 35mm or medium format both have their own autofocus compromises.

IMO

BC

[FredBGG]

Maybe it's all personal taste, but I don't have many issues focusing my Contax, either auto or manual and do a lot of focus then recompose.
IMO

BC

Hi BC
Using a center focusing point and then recomposing when shooting wide open and not with a long lens will lead to focus moving forward or back depending on the re composition.
It's a well documented issue. It is however more of an issue with shorter focal lengths where the angle changes more during re composition.


From the Hasselblad True focus white paper.

Are you shooting wide open with a fast lens?

Here is a test done with the Mamiya DF to illustrate the focus and recompose problem.

Shot with the 80mm at f2.8 and on a panoramic head to keep the distance locked and locked better than any hand held re composition.

The first photo shows the extent of the re composition that is actually quite minor.
About what one would do to do a potrait with a "rule of 1/3rds" composition.



Here is a crop of the feature before recomposition:



Here is a crop after the re composition:


One can clearly see the focus shift. This would result in blured eyes.

It isn't because of the slightly lower sharpness furthur away from the sweet spot of the lens as you can see from the increase in detail
indicated by the red arrows due to the focus shift.




Here are the two crops animated on top of each other to see the difference clearly



This problem gets way worse when shooting with a 50mm.

This type of problem is resolved with certain limitations with Hasselblad True Focus.
You just have to be really careful not to move at all during re composition and to do it slowly enough for the angle (motion) sensor True focus to work.
Also I have seen that any significant vibration like loud music base or a truck going by will kill precision of the motion detector.
Use short focal lengths. True Focus can't measure the smaller angles involved in re composition with longer lenses as precisely. This is
an issue as the depth of field of longer lenses is razor thin.

It will be interesting to see how well this works in the new True Focus II

Here are two shots that would have been problematic with the auto focus limitations of the DF or a Hasselblad without True Focus
due to the  focus and re composition that they would require.





One I shot using the outer most focus point and then very little re composition

The other I shot with live view and no re composition.

[FredBGG]

With the contax I can manuall focus well, which I find more difficult with the DF.
IMO

BC

I agree. While the screen of the DF appears brighter it does not snap into focus as well as the old contax screens.

Also for the Contax Maxwell Optics does a modification/custom mod to the screens that make them work even better.
It's also nice to use the Contax with the waist level finder.

[FredBGG]

The thing I hate about multiple focus points in 35mm, is in horizontal mode they really don't cover the whole 35mm frame so your always doing some form of focus, recompose, or your tempted (too tempted) to compose where the focus point reaches, which really isn't the best way to frame a photograph.
BC

Just resist the temptation What is more important is that you can still use the closest focus point and then only have to make a very small re composition that does not introduce much focus shift.
Also nearly all modern DSLR cameras can do liveview focusing right up to the corners of the frame. You can even use face detection with the D800 if you want to compose all over the place
and have the camera chase the face around the frame. It works remarkable well.

With live view focus (d800) you can also select a small or large focus point. You can also quickly move this focus point around the screen with the joy stick.
There is a second joy stick on the vertical grip too. Also the focus position can be moved around with software on a laptop and very soon on an android phone or tablet
so an assistant to could move that around while the photographer concentrates on the subject.

Also with 35mm DSLR cameras if you are going to shoot with MF aspect ratio you can get the focus points right to the lateral edge of the frame.



With the D800 that's still 30MP

[Gandalf]

It would be nice to have a MF camera with focusing as good as a Canon Rebel   The Pentax 645D would be the closest..... but still no on sensor AF.

I have never used a Rebel, so can't comment, but I'll say this: In my very limited experience, the DF was a great reason to buy a D800. The DF+ is a great reason to buy a new digital back. Focus doesn't hunt and is very quick and responsive considering the mass of glass it's moving. I've never shot with a H-series Blad, but I like to. In some seat of the pants testing, I would say that it is as fast an early Canon DSLR. Nothing earth shattering, but quite an improvement over the DF, which reminded me of an old Nikon 8008s.

How does it really compare with the DF? A side by side video would be interesting.

I don't think a video would show anything and if it did you would write it off as dishonest marketing. If you have them both in your hand, there is no question the DF+ is faster, more accurate and more responsive. Not by a little, but by a real amount. What I am curious about is whether it will focus track anything, and I don't think that it will though I have not had the opportunity to test that. Perhaps Doug would be willing to do that. I'm not talking about shooting race cars, just people walking/jogging/running diagonally toward the camera or across the frame.

The DF+ is a vast improvement over the DF in autofocus and responsiveness, there is no change that I could tell in any other part of the camera and it still feels like an evolutionary improvement over the Mamiya AFD. If you liked the DF you'll love the DF+. If you hated the DF, the DF+ probably won't change your mind and I still can't wrap my mind around how that camera is worth $6,000.
 

However speed is not the only issue.

No argument there. The DF+ is an evolution, not a revolution, but it is a very nice improvement and one that makes medium format much more of a consideration for some of us than it was a few weeks ago.

[bcooter]

Are you shooting wide open with a fast lens?

Sure, I shoot some wide open at f2, 2.4, 2.8 etc. depending on lens, but not that much.  Very little commercial, even editorial work is shot at F2 and even then it's for that dreamy, eyes only in focus portrait look and I don't do a whole lot of dreamy, eyes only in focus portrait work.

This is more the exception rather than the rule for me.



The thing is all cameras have their plus and minuses.  Could I do the work I do with my Contax and use a Hasselblad or a DF?  Sure.  Might go about it slightly different, but  . . . sure.

The other thing is I also use 35mm, when 35mm is required and not because of pixels, though I just like using a medium format camera sometimes. 

Actually would 95% of the time if it wasn't for the pressures of commercial work and shooting in compressed production days.

Few people will argue that 35mm is usually easier and easier is usually faster.

The real thing I don't like about digital 35mm is the vertical crop.  Regardless of the red lines I still see a skinny frame but for horizontal work FF 35mm makes sense. 

The second real thing I don't like about 35mm digital is unlike 35mm film cameras, actually make that 90% of all film cameras, 35mm digital is hard to manually focus.  There is something small and very weird about 35mm digital optical ground plastic.

I've tested this about 100 times shooting background plates, but the focusing screen in 35mm digital cameras shows more focus than the actual file.  I don't know why, just know it does with all of  my nikons and canons.

It's an easy thing to test out.   think about shooting a background in different degrees of out of focus.  Look though the optical viewfinder and you can read a sign in the background, but  the actual file becomes much more out of focus . . . much more.

At least with my Contax and probably the blad and phase, what you see in the optical viewfinder gets much closer to matching what I shoot, at least in the viewfinder-to-file.

Anyway, to me most of this is a mute point.  Sure there is some focus change in recomposing, but I adjust manually and do so it's not a big deal, takes no time.

BTW:  Fred, I don't really see any of this as a Nikon vs. MFD world.  For some maybe, but for most probably not.  I understand you had your issues with Phase and I know better than most that Phase can be challenging when dealing with them directly, though I am sure if you have purchased your DF/phase from one of the two dealers on this board it would have been resolved in a much better way.  I know them both and the Atlanta dealer just helped me with an HMi purchase in a way that no dealer I work with in L.A. could do and not just in cost but service and knowledge of the product.

IMO

BC

[FredBGG]

The second real thing I don't like about 35mm digital is unlike 35mm film cameras, actually make that 90% of all film cameras, 35mm digital is hard to manually focus.  There is something small and very weird about 35mm digital optical ground plastic.

I've tested this about 100 times shooting background plates, but the focusing screen in 35mm digital cameras shows more focus than the actual file.  I don't know why, just know it does with all of  my nikons and canons.

IMO

BC

The default focusing screens in 35mm DSLR cameras are not optimized for manual focusing. Canon does make special a special screen that is slightly less bright than
the default one, but it produces a better depth of field preview and focusing comes in and out with more of a "pop" to it.

Here is a guide to Canon focusing screens.
http://www.learn.usa.canon.com/app/pdfs/quickguides/CDLC_FocusingScreens_QuickGuide.pdf

That said for really good preview of focus on background matte photos nothing beats liveview on a dslr or HDMI output on a large screen.

[FredBGG]

BC



Is this the full frame or a crop? Also can you tell us the focal length/lens