Luminous Landscape Forum

Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: ryandutch on February 17, 2013, 08:25:10 pm

Title: too strong colorfridging with Phase one P65+ shooting architecture
Post by: ryandutch on February 17, 2013, 08:25:10 pm
Hello , i recently bought a p65+ ...thinking it would be better then my Hasselblad 50MP

when shooting on a Cambo Rs with a 28 mm XL schneider with the nice centre filter , and 12 mm of shift to the right ...i get ...

a huge purple fringing ...  

and i thought mmmm

so i made a test setup at home camera fixed .. f 11    shot my LCC shot ,

then i changed backs to Hasselblad 50 Mp

did the same , no changes for the rest

and what did i see ...no purple extreme color fridging with the Hasselblad...  


since everybody is so into Phase ...   maybe share some experiances or help

here are the original files , and some tifs renderings to compare

because of the strong LCC correction , all the reds on the right side of the image are suppressed...


this doesn't look good for the P65...

i am very disappointed.

here are the original files , you can download as you like ....

also 2 tifs to directly compare...

i have no idea...

greetings Rien.



http://rvanr.com/filechute/2%20tifs%20.zip
http://rvanr.com/filechute/H3d-50%20at%20home.zip
http://rvanr.com/filechute/phase%20p65%20at%20home.zip
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 17, 2013, 11:21:00 pm
Here are the tiffs:

(http://farm9.staticflickr.com/8516/8484813482_ecc9c50506_o.jpg)
Hasselblad 50

(http://farm9.staticflickr.com/8392/8483718953_e8bb21a6ed_o.jpg)
Phase 65+

On the right hand side of the frame....
Not only are the reds subdued, but so are the greens.
Neutrals seem to be a bit off too. Greenish shift.

Here is the uncorrected Phase One P65+.

(http://farm9.staticflickr.com/8372/8484893062_13a405b052_o.jpg)

Shows how much it needs to be corrected.

Here is the LCC
(http://farm9.staticflickr.com/8387/8483821003_eac558aa15_c.jpg)

Looking that the problem area the levels are really crushed so there are few values that can be used
to make an accurate correction.

Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 18, 2013, 12:56:17 am
A 12mm shift with the rear element so close to the sensor actually results in quite a high angle.
The difference in sensor design and how light hitting the sensors at such an angle effects the capture.

A retro focus lens design would reduce the angle at which the light hits the sensor, but then the 12mm shift would result in less
distortion correction.

It would be worth while seeing how good the P65+ is by not using lens shift and then correction the perspective distortion
in post..
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: ErikKaffehr on February 18, 2013, 02:47:45 am
Hi,

Just an observation, I would guess that a retrofocus lens would work much better. I think some of the Rodenstock HRs are retrofocus designs. All Hasselblad wide angles are retrofocus lenses except the SWC.

Shifting the lens exaggerates the problem.

The problem is that the light from the lens hits the sensor at very large angles, and that is causing a lot of problems. Retrofocus lenses (Distagons in "Zeiss speak") project the light at a much smaller angle and reduce problems.

Best regards
Erik
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: yaya on February 18, 2013, 04:35:35 am
Hello , i recently bought a p65+ ...thinking it would be better then my Hasselblad 50MP

when shooting on a Cambo Rs with a 28 mm XL schneider with the nice centre filter , and 12 mm of shift to the right ...i get ...

a huge purple fringing ...  

and i thought mmmm

so i made a test setup at home camera fixed .. f 11    shot my LCC shot ,

then i changed backs to Hasselblad 50 Mp

did the same , no changes for the rest

and what did i see ...no purple extreme color fridging with the Hasselblad...  


since everybody is so into Phase ...   maybe share some experiances or help

here are the original files , and some tifs renderings to compare

because of the strong LCC correction , all the reds on the right side of the image are suppressed...


this doesn't look good for the P65...

i am very disappointed.

here are the original files , you can download as you like ....

also 2 tifs to directly compare...

i have no idea...

greetings Rien.



http://rvanr.com/filechute/2%20tifs%20.zip
http://rvanr.com/filechute/H3d-50%20at%20home.zip
http://rvanr.com/filechute/phase%20p65%20at%20home.zip


What happens when you shift the Hassy another 3mm so to get the same AOV as the Phase One?
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: ced on February 18, 2013, 04:41:51 am
Rien here is a test you can make yourself.
I think the Correction File looks very dark so follow the manufacturer's recommendation on the exposure required.
That is the 1st step to try. Keep the same grey balance setting for both the image and correction file.

Another test you can try is to remove the centre filter take your shot then the second shot for the correction use your translucent perspex sheet and capture the file about 2 stops brighter than the main exposure but using time not f-stop and again respect the same grey balance on both then process and see what the results are I guess you have some option control over the amount of correction in the processing software.  Would love to hear if this is any better or worse than what you have now.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 18, 2013, 12:09:09 pm
What happens when you shift the Hassy another 3mm so to get the same AOV as the Phase One?


The problem with the P65+ is more than 3mm (on the sensor) from the right edge so I don't think that is the issue.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Paul2660 on February 18, 2013, 01:40:53 pm
On the P65+ or IQ160, if you have that much fringing, you have lost too much color and or detail that I don't think it's going to be recoverable with a LCC.

The Schneider 28mm has trouble with the P65+ on up from Phase with a shift much past 8mm.  You have another option, the Rodenstock 28mm, which will easily shift to about
10mm with none of this problem.  You will start to hit the outer edge of image circle, and get a hard vignetting which ruins the image in another way.  I have always called this
"the disc"  shows up in all the Rodenstocks eventually but on the 28mm with it's 70mm circle you hit on a shift "left and right" at about 7mm.  Rise and Fall you can get about 10mm
before this shows up, due to the sensor layout.

The best solution would be the 32mm Rodenstock if you have the budget.  You should get 12mm to 14mm before you hit the disc and the lens will be sharp all the way across the frame.

Paul Caldwell
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Paul2660 on February 18, 2013, 01:45:31 pm
Cambo might need to restate that.   It's the lens.  and the IQ180 is even more limited than the 160. 

The P65+ and higher will easily shift to 15mm to 20mm it's very dependent on the lens being used.  The Schneider 28mm is not one that will work well with these backs.

My experience: from various lenses I own.  This is all left and right shift.

Rod 28mm,  8mm max (limited by the disc) not the sensor or lens, it would easily make 10mm
Schneider 35mm, 12mm max, even here there is pretty harsh magenta cast but most times LCC will take it out.  Blue sky is an exception
Schneider 43mm, 18mm max here slight color fade, but recoverable very little magenta cast
Schneider 60mm, 25mm max.  slight color shifts but details at F16 are still strong and image is very good.

Paul Caldwell

Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Paul2660 on February 18, 2013, 02:11:11 pm
No bashing of brands intended, just difference in results.  Not an architecture shooter so I am only speaking for landscapes.  However I can see where rise and fall are very important for this type of work.

Interesting on your results as I had the same issue with casts on the 28mm Rodenstock, until I added the physical CF.  It made a huge difference for me, however it does limit you as in many areas, filters for one.  I see no loss of details but a huge gain in both color and cast.  Plus the fact that it balances out the frame so well.    I still find the 28mm Rodenstock to be my sharpest lens, and just wish it would shift to 10mm (again only limitation I see is the disc which gives the hard corner vignetting).

More good reading on both the 28's here:
http://www.getdpi.com/forum/lens-accessory-reviews/34991-rodenstock-28mm-hr-vs-schneider-super-digitar-28xl.html (http://www.getdpi.com/forum/lens-accessory-reviews/34991-rodenstock-28mm-hr-vs-schneider-super-digitar-28xl.html)

I don't think it's the image circle, but instead the retrofocus or non-retrofocus design.  It's always a trade off as the Schneiders have less distortion, but more cast.  

Curious, have you looked at the Hcam and one or both of the Canon TS-E's?  Here is a link where a good discussion was on this site.

http://www.luminous-landscape.com/forum/index.php?topic=75282.0 (http://www.luminous-landscape.com/forum/index.php?topic=75282.0)

You have the Rod 32mm, which is supposed to be the very best even on the IQ180.  I have never worked with it, just too expensive and heavy.

Paul Caldwell


Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: yaya on February 18, 2013, 02:48:52 pm
Hi Rien,

Since you already own the Rodenstock 32mm then perhaps you can use that one with the P65+ as it'll give you more or less the same AOV as the 28mm (with the 50MP back) and more or less the same perspective control (i.e. amount of useable shift). That way you will still enjoy the extra resolution and portability at the cost of a heavier lens

Just a suggestion...

Yair
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: mjon on February 18, 2013, 04:40:21 pm
A perhaps strange suggestion: rotate the back by 180 degrees and check if this makes a difference. I had a Dalsa sensor back which showed uncorrectible files in one orientation and usable ones in the other one, both with the SK 28 and SK 43 and extreme movements.

Mjon
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 18, 2013, 10:26:54 pm
A perhaps strange suggestion: rotate the back by 180 degrees and check if this makes a difference. I had a Dalsa sensor back which showed uncorrectible files in one orientation and usable ones in the other one, both with the SK 28 and SK 43 and extreme movements.

Mjon
Very good suggestion. To some extent all wide angles with shift used with digital sensors will preform better in one direction than the other, hence the
rumors of some lenses having a bad corner or something.

For example look at the Canon 17mm TS. While the problem is not lens color cast, there is a difference depending on how the light hits the sensor.

Shift to -12mm
(http://media.the-digital-picture.com/Images/Lens-Tests/ISO-12233/Canon-TS-E-17mm-f-4-L-Tilt-Shift-Lens/Crop3/2009-07-01_09-13-35.jpg)

compared to shift +12mm
(http://media.the-digital-picture.com/Images/Lens-Tests/ISO-12233/Canon-TS-E-17mm-f-4-L-Tilt-Shift-Lens/Crop3/2009-07-01_05-34-39.jpg)

I once saw a guy shooting with the canon 24mm TS with the camera upside down...... at first I wondered what the hell he was upto...
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: julienlanoo on February 19, 2013, 04:30:58 am
Mhm thats it, the Dalsa s don t work well with shift, i ve hot a P45+ i want and can buy bigger but at phase one its only Dalsa now :(, so as i love the phase one software i ll stay with that,..
Or might go to the hassy 50,
Question is who s still developping Kodak sensors on MF?..
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Paul2660 on February 19, 2013, 07:08:45 am
Dalsa's do fine with shift as I posted before.  They are just more dependent on the lenses used.  They don't like the wider Schneiders i.e. the 24mm, 28mm.  If you want 15mm of shift on a wide with a P65+  you have to look to the Rodenstocks preferably the 32mm.  The 60mp Dalsa's from Phase one have quite a bit more leeway with shift once you get to the 43mm Schneider or the 40mm Rodenstock both of these lenses can shift to 15mm.  I often shift my 43mm Schneider to 18mm. 

If you get up to the IQ180, then the list of wide lenses that handle shift well, gets much shorter. 

Paul Caldwell
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: BernardLanguillier on February 19, 2013, 07:30:56 am
If you get up to the IQ180, then the list of wide lenses that handle shift well, gets much shorter.

I know I am not helping, but I wonder sometime whether some MF users would not be sharing a form of masochism...  ???

Pay 40,000+ US$ to get an amazing sensor you hope to mount on the most delightfully exotic 10,000 US$ LF camera... only to find out that you can't get the colors right with some of the best 4,000 US$ MFD lenses on earth. ;)

There must be a common sense black hole nearby.

Cheers,
Bernard
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Paul2660 on February 19, 2013, 08:55:25 am
I agree it does make you wonder at times.   :)

Paul Caldwell
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 19, 2013, 12:27:36 pm
I agree it does make you wonder at times.   :)

Paul Caldwell

In part it is about the sensor supplier and what field they are in principally.

Dalsa is part of Teledyne that is principally a military, scientific and industrial equipment supplier.
There isn't really much of a military or scientific need for lens shifting so it's not a priority in their designs.

Kodak, Canon and Nikon/Minolta-Sony are companies that have a long history in the visual art of photography
so their approach is different.

MFD is unfortunately limited by the sensors available in MF sizes and neither Phase, Hasselblad or Sinar have the resources to develop their own sensors.


 

Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Doug Peterson on February 19, 2013, 12:30:59 pm
I know I am not helping, but I wonder sometime whether some MF users would not be sharing a form of masochism...  ???

Pay 40,000+ US$ to get an amazing sensor you hope to mount on the most delightfully exotic 10,000 US$ LF camera... only to find out that you can't get the colors right with some of the best 4,000 US$ MFD lenses on earth. ;)

There must be a common sense black hole nearby.

In my opinion you should never be "finding this out" only after the purchase. Any dealer worth a darn is helping you at every stage of your decision making progress pick out the best back for your needs. This is like saying that you buy a Nikon and a View Camera with dSLR and then "find out" that the mirror-box/chassis/flange-distance severely limit your range of movement and lens selection.

Every combination of camera equipment has inherent advantages/disadvantages. A good dealer aligns them with your budget and priorities, and makes sure you have the option to TEST it in a real world scenario whenever applicable.

If you upgrade from a standard sedan to a porche you may also need to upgrade your tires. It's even possible that the porche would do less well than the standard sedan if you tried to use the same tires.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Doug Peterson on February 19, 2013, 12:33:17 pm
In part it is about the sensor supplier and what field they are in principally.

Dalsa is part of Teledyne that is principally a military, scientific and industrial equipment supplier.
There isn't really much of a military or scientific need for lens shifting so it's not a priority in their designs.

Kodak, Canon and Nikon/Minolta-Sony are companies that have a long history in the visual art of photography
so their approach is different.

MFD is unfortunately limited by the sensors available in MF sizes and neither Phase, Hasselblad or Sinar have the resources to develop their own sensors.

I find much of this post very misleading. I don't have enough time or patience to make a complete reply. But suffice to say that implying Dalsa's sensor designs are less photographically oriented because their parent company has many areas of business is complete BS. Do you know how many non-photographic endeavors Kodak, Canon, and Nikon/Minolta-Sony are engaged in??

Ask 100 photographers who have used both Dalsa and Kodak sensors in a variety of situations for an extended period of time: "which sensor do you find more photographically pleasing, with more natural tonality and better color" and see what you get. Or just google "dalsa vs. kodak".
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Doug Peterson on February 19, 2013, 12:58:06 pm
that is the reason why they invented technical camera's ...for perspective ...
 
all we need now is a manufacturer that doesn't forget to test their chips for
side way adjustments...

the kodakchip  is better for architecture , simple .

Great consideration is given to the design benefits/drawbacks of microlenses and pixel size at both Dalsa and Phase One as products are developed. The idea that Phase One doesn't "test for sideway adjustment" is just crazy wrong. Tech cameras are in fact a heavy design emphasis for Phase One and it's a heavy part of testing from development all the way past release.

So much so that the tech camera market is dominated by Team Phase One with features like an onboard battery (P/P+/IQ), in-camera application of LCC (Aptus II), custom metadata entry (Aptus II), two axis level (IQ/Credo) including autocorrection in C1 for being off-kilter, no-wakeup required sync (P40/P65/IQ/Credo/Aptus-II), long exposure (P+ excluding 40/60), great 100% review (Aptus II, IQ, Credo), super fast interface for in-camera review (IQ/Credo), ability to review the last 10 images from the back when shooting tethered (IQ/Credo), Live View (with limitations, IQ/Credo).

What you're seeing here is what's thoroughly documented by myself and others on the forum, Phase One on their Knowledge Base, and discussed by any good Phase One dealer with a client that is using (or might consider in the future) these kinds of lenses/bodies/backs: 6 and 5.2 micron backs (P40/P65/IQ140/160/180/Credo) do better with the mild retrofocus design of Rodenstock's lenses. The P65+ works very well with the 43XL on up, and pretty well with the 35XL, and even does very well with the 28XL straight on, but will not sustain 12mm of shift. If you came to me when purchasing and told me that shifting 12mm on a 28XL and using the edge of the frame then I would not sell you a 65+. I would instead send you a sample image of a 32HR with 12mm of shift and explain your options:
- a back with a larger micron size (e.g. P45+)
- or a lens like the 32HR with less extreme angle of light (which provides better sharpness, great microcontrast, very little color cast, but comes at the price of added cost, weight, and distortion).

All that said, I think you are overstating the difference compared to your H4. The images you've posted look of comparable quality to the edge of the H4 frame. The IQ, being a larger sensor, allows you to see further towards the edge of the 28XL image circle where color cast becomes more severe. Likewise if you slapped an IQ140 on there you'd find that there was very little color cast at 12mm of shift, but only because you'd have effectively cropped out the potentially problematic area.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Rob C on February 19, 2013, 01:22:01 pm
Remember film? Linhofs, Sinars, DeVeres, Deardorffs, Super Angulons...

Just kiddin'!

;-)

Rob C
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: julienlanoo on February 19, 2013, 04:05:45 pm
Just to know, not at all bashinh on Dalsas, are there any brands still developping on Kodak sensors?... Just to enrich my knowledge ...

What i ve also remarked is that one could find much more specialized backs i.a multishot and achromatic, based on kodak sensors ( the 39mpix one and the 50mpix one) than on Dalsas, is there a reason for that ?...
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 19, 2013, 09:15:57 pm
All that said, I think you are overstating the difference compared to your H4. The images you've posted look of comparable quality to the edge of the H4 frame. The IQ, being a larger sensor, allows you to see further towards the edge of the 28XL image circle where color cast becomes more severe. Likewise if you slapped an IQ140 on there you'd find that there was very little color cast at 12mm of shift, but only because you'd have effectively cropped out the potentially problematic area.

I don't think he has overstated the problem.
Here are the two uncorrected shots overlaid on each other.
It is clear that even if you were to crop them the same the P65+
has significantly more lens cast color artifacting and saturation problems.
Just look at the color of the books. Not even close to comparable to the edge of the H4 50.
The color cast is even visible on the arm chair.
Also the right side is crunched down and darker with the P65+ despite the
exposure being brighter inb the center of the image.
Both shots are without the LCC applied.

(http://farm9.staticflickr.com/8085/8490411056_0a5db0112c_o.gif)
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: siebel on February 19, 2013, 09:19:36 pm
Frankly, this whole thread is a little annoying. All the "problems" discussed here are well documented and have been discussed ad-infinitum here and in numerous other places for a long time.
I am a pro architectural shooter who shoots 98% of my work on an Alpa tech cam with an IQ180. It has limitations. I knew about them when I bought this setup because I did my research and did my testing first, as should you have. I had a P65+ before getting my Aptus 12 and the the IQ180 and back then, the problems with the 28mm SK were well known. Frankly, if you are going to have a go at a manufacturer, you should have a chat to SK about the 28mm. They have stuck their head in the sand in their adherance to their lens design methods, when the issues with lenscast on CCD sensors has been there all along. As pixel size decreases, lenscast gets worse. Sensor development was not going to stop because they insist on symmetrical lens designs. The laws of physics don't change because you want them to. You bought your back without doing enough homework. Suck it up and deal with it. Don't blame Dalsa and Phase. It is normal in photography that as you make changes to major items of kit, a few others might need to be changed too. When I went from the P65+ to the two 80MP backs, my SK 35XL went from 'favourite lens' to 'paperweight'. I understood that this would happen, so I dealt with it in the normal way - I sold it and got a 23HR and 40HR Rodenstock. This was expensive, but a consequence of MY decision to upgrade my back.
Personally, I dont see why massive lens-shifts are seen as such a sacred cow. There is more than one way to skin a cat. I shoot more with my 23HR than anything else and it has barely 3mm shift. I've done what photographers have done since the beginning of photography - I adjusted my methods to accommodate the strengths and weaknesses of the gear I choose to work with. Slightly less available shift has not diminished what my clients think of my work one bit, nor has it tied my hands on shoots.
Sorry if this seems a little blunt, but sometimes someone has to speak up and call a spade a spade.

Siebel
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: ChristopherBarrett on February 19, 2013, 10:16:56 pm
I guess this was never much of an issue with me because I feel that that much shift on that wide of a lens just looks like crap in the first place.  Honestly, the perspective ends up feeling so exaggerated that I believe that it's a poor imaging choice.  Sure, I used to shoot a 65mm on 4x5 and shift it to the edge of the image circle to get the top of a building in... and I did achieve the composition, but it always looked just awful to me.  I don't carry anything wider than the Schneider 35mm with my P65+ and I don't even use the 35 that often.  The 43 almost always just feels right to me... but so did the 115 on 4x5.

Huh... I'm beginning to sound a bit curmudgeon-y now that I'm in my 40's...
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 19, 2013, 11:26:09 pm
I find much of this post very misleading. I don't have enough time or patience to make a complete reply. But suffice to say that implying Dalsa's sensor designs are less photographically oriented because their parent company has many areas of business is complete BS. Do you know how many non-photographic endeavors Kodak, Canon, and Nikon/Minolta-Sony are engaged in??


Not what I said at all. I'm simply pointing out that Dalsa's focus is not on the visual art of photography and that their products are far more focused on
scientific and industrial use. While Kodak comes from a long history of making film that has been used by professionals with tilt shift lenses
Dalsa comes from an industrial, medical, and military "machine vision" background.

Just taking a look at the Dalsa website at their Imaging markets and applications page:
http://teledynedalsa.com/imaging/markets/ (http://teledynedalsa.com/imaging/markets/)

Here is what's listed:
Machine Vision & Inspection
Defense & Security
Medical & Life Sciences
Aerospace
Intelligent Transportation Systems
Scientific

or in more detail....

Machine Vision & Inspection
Semiconductor
Electronics
Flat Panel Displays
Solar Panel
Postal and Parcel Sorting
Food and Packaging
Automotive
Pharmaceutical
General Manufacturing
Web Inspection
Industrial X-Ray / NDT
Explore Machine Vision & Inspection
Defense & Security
ISTAR and RSTAR
Threat Detection
Situational Awareness
Night Vision and Enhanced Vision
Explore Defense & Security
Medical & Life Sciences
Orthopedic and Surgical Radiography
Dental Radiography
Mammography
Bone Densitometry
Ophthalmology
Explore Medical & Life Sciences
Intelligent Transportation Systems
Toll Management
Safety Monitoring
Traffic Flow Control
Speed and Red Light Enforcement
Access Control
Road/Rail/Vehicle Inspection
Explore Intelligent Transportation Systems
Scientific
Crystallography
Microscopy
Astronomy
Spectroscopy
Ultra-High Speed
Explore Scientific

Aerospace
Multispectral
Hyperspectral
High Resolution Panchromatic
Explore Aerospace

Not one mention of MF photography. It is obviously not a priority or focus of the company. And that's Dalsa, not even the parent company Teledyne.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: yaya on February 20, 2013, 02:10:41 am
When we started using Philips (now Dalsa) sensors in MF backs in 1998 they've already made a commitment to develop and make sensors for the photographic market. See http://www.teledynedalsa.com/imaging/products/sensors/area-scan/FTF3020C/ (http://www.teledynedalsa.com/imaging/products/sensors/area-scan/FTF3020C/) and http://www.epi-centre.com/reports/9906cs.html (http://www.epi-centre.com/reports/9906cs.html)

The first larger than a thumbnail Kodak sensor appeared much later.
Ever since 1998 there were more MF backs produced using Dalsa sensors than any other vendor and right now there are more backs being used on view/ tech cameras that are equipped with a Dalsa sensor of 22 or more megapixels compared to other sensor vendors

The 43x32 17MP chip was a custom design, as were/are the 44x33 (28MP and 40MP), the 56x36 (56MP) and now the 54x42 (60MP and 80MP). They've all first appeared exclusively in a digital back and a few of them became an off-the-shelf product some time after that

Also worth noting that in 2000 we've developed our own 6MP CMOS sensor which at the time was larger than any Kodak/ Sony/ Canon device

Just correcting the perspective that some here try to skew...I'm with Bryan, Doug and Chris. If you want a larger & stronger engine you're going to have to change your tyres...not the other way around...

BR

Yair
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Gel on February 20, 2013, 07:46:07 am
Sony make perfume and great sensors.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Bart_van_der_Wolf on February 20, 2013, 08:41:42 am
Not what I said at all. I'm simply pointing out that Dalsa's focus is not on the visual art of photography and that their products are far more focused on scientific and industrial use.

Hi Fred,

And? What does that imply?

Quote
While Kodak comes from a long history of making film that has been used by professionals with tilt shift lenses Dalsa comes from an industrial, medical, and military "machine vision" background.

I'm not sure what that's supposed to mean, but you do realise that most of Kodak's sensors were sold to the very same target groups as Dalsa's, don't you? I seriously hope that you don't think that creative/professional photography was the main market for Kodak's sensor division.

Quote
It is obviously not a priority or focus of the company.

That's a red herring. Just because they sell more for other uses (some of which with very similar quality goals, as would be useful for creative photography, compared to instrumentation and medical/scientific use)? Some of those fields demand much higher quality (color accuracy / noise performance / resistance to environmental influences / etc.) than creative photography. It's sometimes cheaper to keep some of those superior features than to design them out of the standardized production.

Cheers,
Bart
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Bart_van_der_Wolf on February 20, 2013, 01:35:58 pm
i feel your pain Bart.

Hi,

I'm not hurting, I don't even use a Phase One back. You seem to have jumped to a wrong conclusion.

Quote
but don't attack the messenger , go talk to Dalsa , that work mostly for people that are pretty angry too , the militairy complex.
and ask them for better wide angle responsiveness .

I'm not attacking anybody, just wondering about the validity of some of the arguments people use.

When people feel the need to use red herrings to support their position, that is often a signal that something may be wrong with the rest of their arguments.

It's unfortunate that apparently some sensor designs are so sensitive to color cast issues, it's a good thing to discuss that. It may help prospective users avoiding a nasty surprise.

Cheers,
Bart
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: bcooter on February 20, 2013, 01:38:10 pm
Hey Yair, Doug, CB,

Don't you know unless your post mentions space exploration and show a photograph of a Squirrel that your responses have no validity.

Get with the program guys and please stop being logical.

In all seriousness, every camera and sensor has a sweet spot for lenses, or lighting, or subject or all three, every camera I've ever used has the perfect storm of issues depending on lighting, subject and/or lenses.

I can take a Canon, Nikon, Leaf, Phase, Leica, RED, Sony and shoot a specific image and prove to you why that one is the best for that scenario.  Can turn around and do the exact opposite.

I'm not dissing the guy with the problem cause that's a drag man, but I know with any camera that costs over $500 get your hands on one and test the hell out of it in every condition you might work in.

When we bought our first RED it was impossible to buy new with an X sensor and searched for nearly a year to find a seller that would actually sell the camera and transfer the ownership.  When we found the right seller,  our Studio Manager went to Chicago, tested the camera in every way possible, then and only then handed over the check.

It might seem like overkill, but it's a lot better than having any issue your not prepared for.


IMO

BC
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Doug Peterson on February 20, 2013, 01:42:42 pm
*quietly deletes my treasured photo of a squirrel in space*
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 22, 2013, 11:29:37 am
Dalsa's do fine with shift as I posted before.  They are just more dependent on the lenses used.  They don't like the wider Schneiders i.e. the 24mm, 28mm.  If you want 15mm of shift on a wide with a P65+  you have to look to the Rodenstocks preferably the 32mm.  The 60mp Dalsa's from Phase one have quite a bit more leeway with shift once you get to the 43mm Schneider or the 40mm Rodenstock both of these lenses can shift to 15mm.  I often shift my 43mm Schneider to 18mm. 

If you get up to the IQ180, then the list of wide lenses that handle shift well, gets much shorter. 

Paul Caldwell


The important number for architectural photography is NOT the amount of shift in mm, but the angle of correction that the shift produces.

If you have a lens with a retro focus design that positions the lens farther away from the sensor a shift of say 10mm on it will not produce the same amount of
perspective correction as a lens that is closer to the film plane using the same 10mm of shift.

What I am saying is that a retrofocus design will have to be shifted more than a sysmetric design in order to obtain the same correction.
So unless the Rodenstock can be shifted much more than the schneider you really are not changing much.

If one lens is 20mm from the sensor and it is shifted by 20mm the camera will be looking up at 45 degrees.

To acheieve the same with a lens at 40mm from the sensor you would have to shift 40mm... well that's if you actually could.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 22, 2013, 11:38:12 am
Frankly, this whole thread is a little annoying. All the "problems" discussed here are well documented and have been discussed ad-infinitum here and in numerous other places for a long time.
I am a pro architectural shooter who shoots 98% of my work on an Alpa tech cam with an IQ180. It has limitations. I knew about them when I bought this setup because I did my research and did my testing first, as should you have. I had a P65+ before getting my Aptus 12 and the the IQ180 and back then, the problems with the 28mm SK were well known. Frankly, if you are going to have a go at a manufacturer, you should have a chat to SK about the 28mm. They have stuck their head in the sand in their adherance to their lens design methods, when the issues with lenscast on CCD sensors has been there all along. As pixel size decreases, lenscast gets worse. Sensor development was not going to stop because they insist on symmetrical lens designs. The laws of physics don't change because you want them to. You bought your back without doing enough homework. Suck it up and deal with it. Don't blame Dalsa and Phase. It is normal in photography that as you make changes to major items of kit, a few others might need to be changed too. When I went from the P65+ to the two 80MP backs, my SK 35XL went from 'favourite lens' to 'paperweight'. I understood that this would happen, so I dealt with it in the normal way - I sold it and got a 23HR and 40HR Rodenstock. This was expensive, but a consequence of MY decision to upgrade my back.
Personally, I dont see why massive lens-shifts are seen as such a sacred cow. There is more than one way to skin a cat. I shoot more with my 23HR than anything else and it has barely 3mm shift. I've done what photographers have done since the beginning of photography - I adjusted my methods to accommodate the strengths and weaknesses of the gear I choose to work with. Slightly less available shift has not diminished what my clients think of my work one bit, nor has it tied my hands on shoots.
Sorry if this seems a little blunt, but sometimes someone has to speak up and call a spade a spade.

Siebel


So to simplify your response and call a spade a spade.... in moving up to the IQ180 you and your clients have accepted giving up on being able to more freely tilt and shifting a technique that has been the staple of so much professional photography. That is perfectly fine as a personal choice, but hardly representative of photographic equipment advancement.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 22, 2013, 11:44:10 am
For static architecture and wide angle shots why not use stitching?

With a correctly setup stitching head and a high dynamic range DSLR and a distortion free lens
one can obtain 200mp files or more and use distortion plug-ins in photoshop to correct perspective
distortion. The final files are far superior to single shot MF.

I re shot something recently.... interior TV set. It had been shot with a wide angle and an MF.
The corners were no good one enlarged to 44x180 inches. I re shot it with an 85mm. Came out great.
Funny thing is I was not even there to shoot that, but there to do a portrait.
Client was tickled by how I pulled it off with "toys" and it lead to another project involving many days of shooting.

Similar could be achieved with MF stitching, but just far simpler and quicker to do it with a DSLR and automated robotic heads.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Doug Peterson on February 22, 2013, 12:37:22 pm
The important number for architectural photography is NOT the amount of shift in mm, but the angle of correction that the shift produces.

If you have a lens with a retro focus design that positions the lens farther away from the sensor a shift of say 10mm on it will not produce the same amount of
perspective correction as a lens that is closer to the film plane using the same 10mm of shift.

What I am saying is that a retrofocus design will have to be shifted more than a sysmetric design in order to obtain the same correction.
So unless the Rodenstock can be shifted much more than the schneider you really are not changing much.

If one lens is 20mm from the sensor and it is shifted by 20mm the camera will be looking up at 45 degrees.

To acheieve the same with a lens at 40mm from the sensor you would have to shift 40mm... well that's if you actually could.

This is not correct.

20mm of shift results in the same relative frame movement regardless of the design of the lens. Only focal length and amount of shift matter.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 22, 2013, 01:04:09 pm
This is not correct.

20mm of shift results in the same relative frame movement regardless of the design of the lens. Only focal length and amount of shift matter.

I think you missed my point. True it is the same relative frame movement, but the change apparent camera tilt is not the same.

Lets say that from the photographers position he has to "look up at 45 degrees in order to get a building in the from top to bottom.
To achieve the same effect of tilting up the tripod head 45 degrees you would need to shift a lens that is 20mm from the sensor up by 20mm.

A retrofocal lens that is say 40mm from the sensor would have to be shifted up by 40mm to achieve the same apparent tripod head tilt.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Doug Peterson on February 22, 2013, 01:09:35 pm
I think you missed my point. True it is the same relative frame movement, but the change apparent camera tilt is not the same.

Lets say that from the photographers position he has to "look up at 45 degrees in order to get a building in the from top to bottom.
To achieve the same effect of tilting up the tripod head 45 degrees you would need to shift a lens that is 20mm from the sensor up by 20mm.

A retrofocal lens that is say 40mm from the sensor would have to be shifted up by 40mm to achieve the same apparent tripod head tilt.

That is not correct.

To achieve the effect of a tripod-head-tilt of XX degrees requires the same amount of rise (in mm) for two lenses of the same focal length - regardless of whether the lenses are symmetrical or retro focus.

This can be confirmed by either actual use of the equipment or geometry taking proper account of the effect of retro focus design on the basic optical principals of a lens.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: yaya on February 22, 2013, 01:12:49 pm
That is not correct.

To achieve the effect of a tripod-head-tilt of XX degrees requires the same amount of rise (in mm) for two lenses of the same focal length - regardless of whether the lenses are symmetrical or retro focus.

+7

...and retrofocus design moves the exit pupil, not the lens...
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Doug Peterson on February 22, 2013, 01:16:19 pm
+7

...and retrofocus design moves the exit pupil, not the lens...

It's been a while since I got a +7...

What's the Russian judge say?  ;D
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: ErikKaffehr on February 22, 2013, 01:27:47 pm
5.2

He prefers Ludmilla because she...

Best regards
Erik


It's been a while since I got a +7...

What's the Russian judge say?  ;D
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Paul Ozzello on February 22, 2013, 02:35:30 pm
That is not correct.

To achieve the effect of a tripod-head-tilt of XX degrees requires the same amount of rise (in mm) for two lenses of the same focal length - regardless of whether the lenses are symmetrical or retro focus.

This can be confirmed by either actual use of the equipment or geometry taking proper account of the effect of retro focus design on the basic optical principals of a lens.

Pictures and diagrams to follow...

 ;)
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: adammork on February 22, 2013, 06:24:21 pm
I think you missed my point. True it is the same relative frame movement, but the change apparent camera tilt is not the same.

Lets say that from the photographers position he has to "look up at 45 degrees in order to get a building in the from top to bottom.
To achieve the same effect of tilting up the tripod head 45 degrees you would need to shift a lens that is 20mm from the sensor up by 20mm.

A retrofocal lens that is say 40mm from the sensor would have to be shifted up by 40mm to achieve the same apparent tripod head tilt.

I'm sorry, but you are completely wrong..... And for the record, I make a living shifting lense on 98% of my images.

/adam
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: ChristopherBarrett on February 22, 2013, 09:17:46 pm
I'm sorry, but you are completely wrong..... And for the record, I make a living shifting lense on 98% of my images.

/adam

I concur... and have used shift on about 99% of my P65+'s 45,192 captures.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Stefan.Steib on February 23, 2013, 01:26:49 pm
As Doug already said - Fred you err.
it´s only about image angle and relative movement.

That´s why the HCam (and the FPS) are working.

And that´s what I would propose to Ryan- if you want to use your P65+ WITHOUT color fringe use an HCam.

greetings from Germany
Stefan
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 24, 2013, 12:01:58 am
This is not correct.

20mm of shift results in the same relative frame movement regardless of the design of the lens. Only focal length and amount of shift matter.



Unless you use some lens tilt or swing.
Would you not need to use more shift on a retro focus lens when using tilt or swing to bring the image back within the image circle
when using a combination of tilt/swing and shift.

I shoot mainly shallow depth of field and use tilt and swing along with shift.

With no tilt or swing I see it's the same...

Main reason whey I would go to my 4x5 rather than the Fuji gx680 if I needed a combination of tilt/swing and shift
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: JoeKitchen on February 24, 2013, 07:53:09 am


Unless you use some lens tilt or swing.
Would you not need to use more shift on a retro focus lens when using tilt or swing to bring the image back within the image circle
when using a combination of tilt/swing and shift.

I shoot mainly shallow depth of field and use tilt and swing along with shift.

With no tilt or swing I see it's the same...

Main reason whey I would go to my 4x5 rather than the Fuji gx680 if I needed a combination of tilt/swing and shift
The further a lens is from the sensor the more the image circle will be skewed by the same amount of tilt.  For instance, if you are working with a symmetrical 35mm lens and you tilt it 5 degrees, in order for the center of the image circle to be in center frame, you would need to shift the back tan(5)x35mm, or 3.06mm.  If the lens is a 35mm retro focal with a true focal length of say 70mm, to achieve the same thing, you would need to shift the lens tan(5)x70mm, or 6.12mm.  

However, this only effects how far away the center of the image circle will be shifted from the center of frame.  This will have no effect of how much you will need to shift to get the same view after the centers are lined up.  This is because both lenses have the same angle of view, meaning that the same object projected through the lens in both lenses will be the same size in both of the lenses' image circles.  If this was not the case, than they would not show the same angle of view.  
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: FredBGG on February 25, 2013, 10:40:21 pm
The further a lens is from the sensor the more the image circle will be skewed by the same amount of tilt.  For instance, if you are working with a symmetrical 35mm lens and you tilt it 5 degrees, in order for the center of the image circle to be in center frame, you would need to shift the back tan(5)x35mm, or 3.06mm.  If the lens is a 35mm retro focal with a true focal length of say 70mm, to achieve the same thing, you would need to shift the lens tan(5)x70mm, or 6.12mm.  

However, this only effects how far away the center of the image circle will be shifted from the center of frame.  This will have no effect of how much you will need to shift to get the same view after the centers are lined up.  This is because both lenses have the same angle of view, meaning that the same object projected through the lens in both lenses will be the same size in both of the lenses' image circles.  If this was not the case, than they would not show the same angle of view.  

But you are more likely to use up more shift to center the lens and may not have enough left to shift as much as needed for perspective correction with a retro focus.

However this would also depend on the tilt or swing direction.
Title: Re: too strong colorfridging with Phase one P65+ shooting architecture
Post by: Willow Photography on February 27, 2013, 05:51:00 pm
i'm sending it to capture integration , they gonna look at it , it might be a problem with this particular back

i am not in the position to generalize about phase one backs.

cause i have only seen this one.

and that is realistic.




Hi Ryan

How did it go with your P65+ and the 28mm?
Did you send it to CI and did they find anything wrong with your back?