Technical camera obsolete? (keystone correction vs. shift)

[voidshatter]

When the IQ3 100MP was released some of us believe that with the Schneider 35mm LS blue ring we could get rid of the technical cameras and just rely on keystone correction in post processing.

There are advantages of technical cameras, such like size and weight. Below shows the Schneider 35mm LS blue ring vs Rodenstock 40mm HR-W blue ring side by side:





And this is a comparison of camera sizes among Alpa 12 STC, Phase One XF+ and Nikon D810A:



The DSLR style cameras are heavy and bulky, but more durable (weather resistant, solid), with auto-focus.

What's the image quality difference?

Below shows a comparison between the two following setups from the same location (both shot at f/8 with the IQ3 100MP):

Left: Schneider 35mm LS blue ring (35LS) shooting upwards with keystone correction in post processing;
Right: Rodenstock 40mm HR-W blue ring (40HR) shifted 12mm with LCC correction in post processing.



Region (1) is at the center of the 35LS image circle, but a bit far away from the center of the 40HR image circle. The 35LS is a tad sharper here (Left: 35LS; Right: 40HR):



Region (2) is near the edge of the 35LS image circle, and near the center of the 40HR image circle. The 40HR is a tad shaper here (Left: 35LS; Right: 40HR):



Region (3) is at the edge of the 35LS image circle, and at the edge of the 40HR image circle. Due to pixel re-sampling during keystone correction, the 35LS is softer in the top corner (Left: 35LS; Right: 40HR):



I have no doubt that the DSLR style cameras such like the XF+ system can produce satisfactory results for almost all clients. For tech geeks the technical cameras still have an edge for corner sharpness.

 

[stephengilbert]

Gotta love the energy. Another day, another sky is falling thread.

 

[PeterA]

You aren't comparing a camera with shift to a non shift camera though are you? You are comparing post shot processing between one type of lens and another...



*apologies - I just noticed that you do state that you used 12mm shift ...

 

[Don Libby]

I guess we've moved on to yet another Phase One issue. Wake me up when he starts talking about the camera strap or did I miss that one ?

 

[DougDolde]

Damn what a toy box !

The ones shot with the HR 40mm do look more detailed to me.

 

[stephengilbert]

Tech cams don't need straps.

That's what makes them cost competitive.

 

[torger]

Voidshatter may express himself in a more provocative way than this forum can handle, but fact is that he does provide us with very interesting and relevant test results and I'm very grateful for that.

That tech cams may be obsoleted by cameras like the XF is not that provocative, I've even seen it hinted by Phase One dealers. The thing is of course that the new CMOS has 1) so high resolution that cropping and keystone correction becomes more feasible than it was with lower resolution sensors, and 2) the tech cam lens compatibility leaves things to be desired. Additionally, Schneider has discontinued their Digitar lens line, Copal shutters have been discontinued for some time and many of us believe that Rodenstock have made their last tech lens. Making lenses as much retrofocus as the new CMOS really requires I think will make the lenses unreasonably large and will require focal plane shutter or new tech leaf shutter, or they will need to simplify optical design making them perform no better than Phase One XF lenses, or probably worse if you don't have lens corrections applied.

So it's not uncontroversial to expect that there will be a move from tech cameras to systems like the XF and Hasselblad H in the coming years. This makes a test like Voidshatter's here extremely interesting.

I've seen the opposite too, users that say their own gear is oh so excellent and never complain about a thing, and suddenly they're using some other system and selling off their old gear and we never got to know what the reason was. I think a main aspect about a forum like this is to share technical aspects about camera gear so we can make informed decisions. Of course we will have different opinions on what's important and what's right for me is not necessarily right for you, but when someone like Voidshatter shares the hard data like here we can see for ourselves.

And from the data we still see that the 40HR has a clear edge for pixel peepers, but we also see that the keystone option is not that bad and provides a real alternative to anyone that can accept that type of post-processing workflow.

To me, a key thing about tech cams is to be able to create the image in a traditional photographic way and use my digital back just as a drop-in replacement of a film back. I want to minimize post-processing work. That is I have an interest in how the creative process is, not just the end result. This means that I would prefer using a tech cam even if the result would be slightly less sharp. The small and light lenses is also an important factor to me as I'm carrying many lenses as I prefer not having to crop much, that is be as close to the end result as possible when I look at the ground glass.

I also know from data shared in this forum that the IQ3 100MP is not for me, as tech cam lens compatibility is not satisfactory to me, as color stability/fidelity, symmetrical lens support and movement flexibility is more important to me than megapixels, dynamic range, high ISO, long exposure and live view (which indeed is much better on the CMOS). Thanks to data shared I know exactly what trade-offs I'm making, and using dealers for that where I live (the closest dealer is 1000km away and knows nothing about tech cams) is simply not feasible. So please let people share valuable information without getting a flood of negative comments.

 

[tjv]

I actually think this is an interesting comparison. A 40HR with 12mm shift VS the new 35mm LS with no shift but keystone corrections applied.

To my eye the 40HR looks dramaticlaly better on points 2 and 3 but slightly worse (minimal) on point 1. It'd be interesting comparing the RS 32mm HR to the 35mm LS, all be it cropping the former to match the later this time. Seeing this however, it seems pretty clear to me that using a tech cam with excellent lenses produces significantly better results than relying on software. But we're talking about 100mpx captures here. You can afford to throw away some pixels!

I think this kind of test is interesting because sometimes, despite loving what I'm using, I do wonder if I'm beating a dead horse or am some kind of photo-masochist.

 

[Pradeep]

Awww guys, give him a break.

I don't seen him bashing Phase in this thread, if anything he is saying it may be just as good or better to use it compared to a tech camera. If you can get by with software correction instead of using TSE then it opens up a lot more opportunities with so many camera systems. I find this a very interesting post, and IMHO quite useful.

And yes, he does seem to have a lot of energy and passion for what he believes in. That is not such a bad thing is it?

 

[mjr]

I think this is far more interesting than the whole 3100 has an issue because it won't do 30 min exposures without dark frame very well. I have always considered the use of a tech cam to correct perspective etc. at the time of capture to be far better than stretching pixels in post, something has to give if you are doing large corrections, it doesn't actually look too bad but as has been said, with 100mp you have plenty of latitude for reducing if necessary and still having an excellent file.

I think that for people with a tech cam then it's a non issue, for those without, it's interesting to see the differences, I don't think anyone would spend the money needed for a decent tech cam kit if they already own an XF and 3100 with a 35mm but for those with lower mp backs, I feel the tech cam still has a lot to offer.

Mat

 

[tjv]

The most interesting question in my mind is really what the technical camera makers and Rodenstock as sole surviving tech lens maker will do from here. Considering current pixel / sensor architecture I'd say something has got to give.

Perhaps we'll see XF / H mount SLR TS lenses soon? If the sensor stays the same and pixels keep getting smaller, what other options are there for the last of us die hard tech users?

 

[mjr]

Film!

 

[etrump]

Thanks for the post, I'm not sure any of this is a new revelation but nice to see how well the 3100 handles the shift. In reality these images could be made much closer (both ways) with post processing. The issue in my mind is not the 3100 but the 3150 or 3200, eventually something is going to give. I've used extreme shift for stitching and the LCC correction on the edges gives a much worse smudging problem for me than the issues brought on by panning.

 

[Thomas Erskine]

No, with photography, It's always better and easier to do things that the time of capture.

If you do keystone correction in post production you have to deal with all these problems.
-more time spent in post production
-Much sharper corners
-what you see, is not what you get. (If you get the framing wrong, it destroys your photograph)
-all your lenses are longer because you have two allow for Keystone correction.

Is MF Digital + Alpa better that Canon or Sony a7 with Canon TS-E lenses? Is the Alpa worth the extra money? That's probably different for every photographer.

 

[Paul2660]

Ed, you beat me to it, thanks to Void for taking the time to do this, and it does show @ 12mm the 40mm HR-W can do a very good job on shifting, cleans up very nicely.

A few other thoughts.

1. I like the picture comparisons, with the 35LS and 40 HR-W, the 35LS is a great lens, but it's heavy and add to an already heavy XF, and you have quite a bit of camera to carry all day. Optically as shown in Voids testing however it's a great piece of glass. I sure would have liked Phase to add weather sealing to both the XF and the Blue ring lenses.

2. The amount of softness on the 35LS, more than likely would sharpen right back up with Picture + or similar software, enough that I don't feel it would show in a print.

IMO an excellent comparison. I agree keystone correction in post can take a while and it took me longer than it should have to learn it in C1, but once you understand the logic it does a great job. LR's newest tool set makes this much faster.

Paul C

 

[Jamgolf]

Obsolete in the sense that it been replaced by something better?
I don't think I can agree with that - not yet, at least.

Post processing tools have improved but there is certainly a cost. Throwing away pixels to do keystone corrections means:
(a) a wide angle lens becomes not-so-wide
(b) throwing away resolution that we paid $$$ for.
Personally I am unwilling to do that and do not think that is better.

I agree they are on an end-of-life path based on facts Anders Torger already stated but I don't think technical cameras are *obsolete*.

 

[stngoldberg]

My technical camera allows rise and fall, shifting as well as tilt (in my opinion the most important feature) with a variety of focal lengths.
I really value this combination of features.
Stanley

 

[f8orbust]

@OP - great post - no idea why some folks jumped on you - this is a useful test that no one else has done (AFAIK) and that no dealer is going to do publicly (for obvious reasons).

'Obsolete' is a bit harsh right now, since as someone pointed out there's still a thing called film (though most folks getting into that are shooting LF or ULF). But, in terms of 'digital' it's not far off the mark; a couple more generations of (almost) unshiftable DBs, compounded by a couple more generations of mirrorless MF, compounded by S/K (and R/S?) stepping aside ... yes, I can see the appeal (and thus availability) of this type of camera declining significantly.

Interesting that Linhof & Studio in the UK have decided to sell the X1D...

Jim

 

[drevil]

Perhaps we'll see XF / H mount SLR TS lenses soon?

Considering how large the 35mm blue ring is already, what beasts would those TS lenses be? :bugeyes:

If my dream of changing my profession to architecture photography in the future, i will still go the tech cam route for sure.

 

[Geoff]

Considering how large the 35mm blue ring is already, what beasts would those TS lenses be? :bugeyes:

If my dream of changing my profession to architecture photography in the future, i will still go the tech cam route for sure.

A while back, did a similar kind of test with a Leica MM. Local dealer lent a 28PC Schneider (from the R series, via adapter) to be compared with his newer 21 SEM lens. The 28PC was shifted 11mm on the diagonal, to compare with a cropped-to-match image from the 21. In a 17 x22 prints, there was very little difference. I'd guess in larger prints, loss of resolution would have been an issue for the 21.

This falls under the "crop with newer lenses and with more resolution" for PC, vs. shifting an older PC lens. Note the 28PC is subject to variations in quality - this one seemed pretty good, but its not equal to a good view camera lens shifted. OTOH, the 21 is a real gem. Can post images if interested.