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Author Topic: Dalsa 6um vs Kodak 6um for tech wides  (Read 1907 times)
torger
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« on: August 11, 2014, 06:07:46 AM »
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I currently use a 33 megapixel back. While resolving power is okay for my style it would not hurt to reduce aliasing artifacts by increasing resolution a bit. So I'm longterm investigating going to an Aptus-II 10 (Dalsa 6um) or the recently discontinued CFV-50 (Kodak 6um).

I like Dalsa, but I also like Schneider Digitar wides like the SK35. The Dalsa 6um show quite strong color cast, microlens ripple and crosstalk when these symmetrical wides are shifted. While mostly correctable the files are considerably less robust after that. My current back has much less issues, less color cast, no microlens ripple, lower amount of crosstalk.

The question I have is how does Kodak 6um technology compare. Is it any better concerning these issues, or is it just as limited as Dalsa 6um?

(It's a pity those damn DSLRs exceeded 33 megapixels so all MFDB products with tech wide friendly sensors got discontinued :-). Megapixel and resolving power is key to sell MF gear though, no way around it.)
« Last Edit: August 11, 2014, 06:21:00 AM by torger » Logged
ondebanks
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« Reply #1 on: August 11, 2014, 10:58:17 AM »
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Hi Torger,

The 50MP Kodak CCD has no microlenses; the 6 micron Dalsa ones do (this surprised everyone when it was finally revealed, via Dalsa's belated 60MP datasheet release, since their quantum efficiency remains rather low). I understand that microlenses are not the only cause of crosstalk, colour casts etc. but they would be the major contributor to such problems.

Certainly Dalsa's "optimized" microlenses are more techlens-friendly than Kodak's microlenses (18/31/40 MP sensors), but they are still less friendly than any non-microlensed sensor like the Kodak 50MP one.

You'll also get better long exposures with the Kodak chip, should you need that.

Ray
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Theodoros
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« Reply #2 on: August 11, 2014, 11:52:15 AM »
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I currently use a 33 megapixel back. While resolving power is okay for my style it would not hurt to reduce aliasing artifacts by increasing resolution a bit. So I'm longterm investigating going to an Aptus-II 10 (Dalsa 6um) or the recently discontinued CFV-50 (Kodak 6um).

I like Dalsa, but I also like Schneider Digitar wides like the SK35. The Dalsa 6um show quite strong color cast, microlens ripple and crosstalk when these symmetrical wides are shifted. While mostly correctable the files are considerably less robust after that. My current back has much less issues, less color cast, no microlens ripple, lower amount of crosstalk.

The question I have is how does Kodak 6um technology compare. Is it any better concerning these issues, or is it just as limited as Dalsa 6um?

(It's a pity those damn DSLRs exceeded 33 megapixels so all MFDB products with tech wide friendly sensors got discontinued :-). Megapixel and resolving power is key to sell MF gear though, no way around it.)

If I was you, I would stay with what I have...  Wink By the way, is it a Sinarback or a Leaf what you now use?
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torger
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« Reply #3 on: August 11, 2014, 01:03:26 PM »
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Thanks Ray.

I think the microlenses is only responsible for the ripple shading effect, crosstalk could be equally bad without them. The ripple effect is only visible when there is quite strong crosstalk already by the way. C1 can cancel out the ripple effect quite efficiently, but crosstalk it cannot. I have an own algorithm for that in the works but I've had to put it on ice for a while (exhausted trying), my current design does not handle as strong levels of crosstalk there is in a shifted SK28 with 6um Dalsa.

I have many tests files with SK tech wides + 6um Dalsa (various backs) so I have detailed info on their performance, but zero files with the Kodak, as Hasselblad isn't widely used on tech cams.

Theodoros, I use a Leaf Aptus 75. Apart from it's a bit buggy and you need a good copy (my first two couldn't handle chilly weather) it's a great back, and you can zoom in to 100% on the back to check sharpness which is useful to me using a view camera. Aptus is unique with this feature of the older backs. (CFV-50 builtin demosaicer is next to useless for sharpness check).

Staying with what I have is not a bad advice. I'm (hopefully) not going into the trap of upgrading the back and then having to upgrade my wide lenses to Rodenstocks. I'm happy with my lens line, traditional large format style designs, just like I want them. It seems like Aptus-II 7 is the last back that was made the feels like designed (with the limits of the sensor technology at the time) for the lens line I use. Oh well, the P45+ is great too, just no sharpness check on screen.

The awful truth is however that I'm looking into a dead end, I'll have to pass through Dalsa 6um sooner or later, unless there is very soon coming some new sensor technology to MFDBs that actually move forward instead of backward concerning wide angle compatibility.
« Last Edit: August 11, 2014, 01:06:42 PM by torger » Logged
Theodoros
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« Reply #4 on: August 11, 2014, 01:19:04 PM »
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Theodoros, I use a Leaf Aptus 75. Apart from it's a bit buggy and you need a good copy (my first two couldn't handle chilly weather) it's a great back, and you can zoom in to 100% on the back to check sharpness which is useful to me using a view camera. Aptus is unique with this feature of the older backs. (CFV-50 builtin demosaicer is next to useless for sharpness check).

Staying with what I have is not a bad advice. I'm (hopefully) not going into the trap of upgrading the back and then having to upgrade my wide lenses to Rodenstocks. I'm happy with my lens line, traditional large format style designs, just like I want them. It seems like Aptus-II 7 is the last back that was made the feels like designed (with the limits of the sensor technology at the time) for the lens line I use. Oh well, the P45+ is great too, just no sharpness check on screen.

My advice (to keep the back) is based on...

1. I don't think that a 50mp sensor will reduce moire cases as much as to make them disappear...,
2. I would avoid micro lenses,
3. The back is one of the best around with tech/view cameras because additionally to the "perfect" pixel size of 7.2mμ, it also has considerably shallower pixels than the Kodaks which favours movements a lot,
4. I believe that the Dalsa 33mp sensor is the most "accurate" sensor ever made (great DR too)... if only they would make a 41.5mp "FF" version of it...  Undecided

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torger
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« Reply #5 on: August 11, 2014, 02:02:27 PM »
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For tech camera and my current lens line I actually like the 36x48mm size, well Kodak's 37x49 would not hurt, but fullframe 645 I think would be a bit tight concerning shift margin with the available image circles. I've noted that I shift larger amounts now than I did before, mainly because I shoot more in steep terrain.

Feeling limited in shifting would lower the enjoyment factor when shooting, and that's the key thing I'm using this system. I also prefer my solution with having lots of lenses (I have 7) instead of a higher res back fewer lenses and cropping. Framing with a proper focal length at shooting time is just more pleasing than cropping in post.

Concerning accuracy DR etc I'm quite agnostic, I can get good results from any fairly recent sensor, when that sensor performs well. I know the Kodak 6um performs worse concerning accuracy and DR than Dalsa 6um, but it would not be a problem for me. I do landscapes, not art reproduction.

SK28 shifted on a Dalsa 6um is however really taxing on its performance, so much that many/most/all(?) dealers have stopped selling the SK28 (which is not a bad lens if the sensor would not crosstalk as much as they do). It would be truly interesting to know how a CFV-50 would cope with that lens, or just even the SK35 (which is the wides I got currently).

Concerning aliasing, ideally I'd like that my f/11 shots looked as smooth as my f/16 shots do now when pixelpeeping. With the 33 megapixel back at f/11 there's often clear aliasing in fine details, while at f/16 most has been smoothed away with diffraction. I haven't really compared if that is the case, 6um is not so much smaller than 7.2um, but possible a better fill factor will help out too. But maybe you're right, improvements in aliasing may be weak, and if so the argument for an upgrade becomes even weaker.

The reason I'm concerned by aliasing more than many other image quality parameters is that that is what make "over-enlargement" look bad. I'd like to store images that I feel don't have any limit on enlargement, that they only look smoothly soft up close if blown up to huge sizes, kind of a large format film quality.
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gregoricivera
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« Reply #6 on: August 16, 2014, 04:27:38 PM »
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Hi Torger, same debate here. I use an Alpa+ Rondenstocks 40 & 70+ Aptus 75s. Moire and artifacts in the fine detail ( i.e diagonal lines in a building far in the background) made me want to go for a back upgrade. I mostly stitch to get a final image that has 4:5 aspect ratio and around 56mpx, but wouldn't mind having that same resolution from a single shot. I cannot decide wether to find a used P65, buy a Credo 60 or stay were I am with the known issues. Nothing is perfect I guess.
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torger
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« Reply #7 on: August 18, 2014, 03:45:07 AM »
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With the Rodenstocks which are a bit retrofocus you have less issues, so you will be pleased with the performance. With the P65+ you lose the focus/sharpness check though, but using an Alpa you probably don't use it as much as I as a view camera user do. I think a good deal on a second hand or pre-owned P65+ would be a great upgrade for you, but I don't know how cheap Credo 60 are these days, maybe it can compete with a P65+ in pricing?
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« Reply #8 on: August 18, 2014, 04:14:36 AM »
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Hi Torger, same debate here. I use an Alpa+ Rondenstocks 40 & 70+ Aptus 75s. Moire and artifacts in the fine detail ( i.e diagonal lines in a building far in the background) made me want to go for a back upgrade. I mostly stitch to get a final image that has 4:5 aspect ratio and around 56mpx, but wouldn't mind having that same resolution from a single shot. I cannot decide wether to find a used P65, buy a Credo 60 or stay were I am with the known issues. Nothing is perfect I guess.

My advice is always the same...best is to try! You can contact your local Mamiya Leaf dealer and ask them to test a Credo 60.
In my experience with the Rodenstock lenses you will not face any issues although I would still recommend using LCC to get the best out of the files.

BR

Yair
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« Reply #9 on: August 18, 2014, 07:54:36 AM »
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On the 60MP Dalsa backs, the 40mm Rodenstock shows the ripple effects on shifts of 15mm or greater.  The Schneider 43XL showed them by 12mm and they were much more noticeable. C1 so far seems able to remove them 100%from the 40mm but not all the time from the 43XL.

43Xl also showed much stronger color cast on shifts Nd loss of color/saturation which I now assume is due to crosstalk.

Torger, it's a shame IMO that Phase One has not reached out to you. I have to assume that they are working on  similar software design to remove the effects of crosstalk. They will need something when the next CMOS sensor is released to the field if this CMOS sensor has micro lenses. So far it seems that all CMOS has some form of micro lenses.

You sure can see the crosstalk issues on the Sony A7r when it's shifted past 12mm when used with the Arca DSLR2.  15mm Shifts become close to monochrome in the greens.

Paul

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torger
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« Reply #10 on: August 18, 2014, 08:29:55 AM »
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Torger, it's a shame IMO that Phase One has not reached out to you. I have to assume that they are working on  similar software design to remove the effects of crosstalk. They will need something when the next CMOS sensor is released to the field if this CMOS sensor has micro lenses. So far it seems that all CMOS has some form of micro lenses.

Well I guess they could wait until I got it working 100% Smiley. Normal LCC correction I have a better algorithm than C1 already available in Lumariver HDR, but it doesn't do crosstalk suppression/cancellation yet (it does fix the demosaicing issues you get with heavy crosstalk though, which C1 does not).

I have got good results with crosstalk cancellation for mild/medium crosstalks, but I have not got it to work with a heavily shifted SK28 on 6um Dalsa for example, the crosstalk is so strong that my algorithm becomes unstable. I tried hard during the spring, but have now put the work on ice for a while, it's taking an insane amount of time compared to how many sales one can get, so it's more of a hobby project. My current algorithm tries to make a "mathematically correct" solution, but I think one have to make a different approach for stronger crosstalks because signal/noise ratio becomes too poor to make a mathematically correct solution, meaning that noise knocks the algorithm out of balance and you get disaster rather than improvement.

I don't think Phase One will try to make a crosstalk cancellation algorithm for C1, it's too complicated to make commercial sense, and only affects wide angle tech camera applications which I don't think is important enough for them. We'll see. Actually I find it more likely that Rodenstock or Schneider makes new wide angle lenses in the future which are even more retrofocus to cater the new CMOS sensors.

At some point I will continue to try making my algorithm to work even for the hard cases, just for us in love with symmetrical (or weak retrofocus) tech wides Smiley. But for now I need to focus my time on more urgent work.
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« Reply #11 on: August 18, 2014, 09:40:28 AM »
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That only leaves, then a totally new CMOS, no micro lenses or all new tech lenses which move out towards the distance a DSLR 645 lens does.  Amount of room for the mirror box.  Never really sure why they didn't just do this in the first place, however I guess optically it's hard to do and hold the DOF hyperfocal distance, and corner sharpness the current line of lenses does.   No micro lenses on CMOS, then the higher iso settings will get interesting as it's my understanding that is their main reason for being on the chip, i.e. light gathering.   I have assumed that the CCD Dalsa 60MP chips in the 160, and 260 Phase backs have some form of micro lenses on them.  Not sure on the 180, but the pitch of the pixels seems to be the issue there.

Your current algorithm should work great on the 40mm shifted to 18 or so, I would love to try it.  I can send you some images, if you are interested, when you get back to it.

Paul
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Paul Caldwell
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torger
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« Reply #12 on: August 18, 2014, 04:35:35 PM »
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Microlenses are not the enemy, but rather the pixel stack height. A pixel on an MF sensor today is about as high as wide and the photo diode is at the bottom of the well, meaning that it can't handle low angles of incoming light - that is the problem. Microlenses actually help that somewhat, small pixels without micro lenses would probably perform even worse (although we would probably not get the ripple).

The older microlens-free sensors also have larger pixels, which reduces the height/width ratio, which is the key why they work better. The lack of microlenses is not all good though, it means that there is more "empty space" between pixels where no light is captured, ie you get more aliasing than when the light is steered from the edges of the pixel into the photo diode. You also get a lower ISO but for the wrong reason (light thrown away rather than a bigger light capture capacity).

The main reason microlenses has such bad reputation is the early generation ones used in the Kodak sensor of the P30+ and others. The microlenses on modern sensors are much better. But better still would of course be to place the photo diode on the surface of the pixel and have it cover the full pixel area, but sensor manufacturing technology is not there yet, at least not for MF-sized sensors.

Concerning retrofocus lenses it's revealing to look at Phase One's 645DF wide angle lenses without C1 lens correction algorithms applied (use rawtherapee for example), there's lots of chromatic aberrations. With tech lenses there is no such lens corrections, there cannot be since there is no information in the exif data like shift and tilt settings or even aperture and focal length that would be required for that to work. Tech wide lenses thus uncorrected exceed the performance of 645DF wide lenses even when they are corrected (concerning sharpness), and that's impressive.

The reason this is possible is not some magic superiority in the manufacturing process, but a matter of optical design formula. These lenses have less maximum aperture and are less retrofocus (or even symmetrical), then you can make sharper wide angle lenses, with less barrell distortion too. The drawbacks of this optical design are smaller max aperture, more vignetting (requiring center filters) and being tough on current sensors due to low angle of incoming light off center.

As tech cams won't provide exif data of lens and movements settings anytime soon (that would require collaboration between multiple tech camera makers, an electronic shutter maker and digital back makers, ie it won't happen), software correction of the optics is not feasible, so simply having superior optics will still be required well into the future.

If due to sensor design tech lenses much be more retrofocus in the future (eg if CMOS sensors take over and there's no solution to the crosstalk problem) you'll either need extremely complex optical formulas (making the current Rodenstock 32HR seem light, trivial and cheap Smiley ) or more compromised lens types which would give less good sharpness than the 645 mirror cameras.

Personally I believe the traditional "large format" lens designs have a place in photography and I hope that CMOS sensor technology improve on this aspect before it's too late. The SK28 was discontinued not because it's a bad lens, but because the modern backs don't support that lens design. Much more lenses in the current tech cam wide angle range would need to be discontinued if CMOS with current performance becomes the new standard.

Thanks for test file offer, I have already got a bunch of test files which I have not had time to sort and look at yet so I'm not yet sure I need any more than I got. I just need more time Smiley , I'll get back to you if I need more files later.
« Last Edit: August 18, 2014, 04:39:50 PM by torger » Logged
Paul2660
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« Reply #13 on: August 18, 2014, 04:53:03 PM »
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Torger. Was the new SK28 discontinued?  This would mean only the Rodenstock 23mm and 28mm are left with their narrower 70mm image circles in this wide focal range ie less than 30mm.

Thanks
Paul

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Paul Caldwell
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torger
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« Reply #14 on: August 19, 2014, 02:58:56 AM »
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Torger. Was the new SK28 discontinued?  This would mean only the Rodenstock 23mm and 28mm are left with their narrower 70mm image circles in this wide focal range ie less than 30mm.

Well, "semi-discontinued" I guess, if you really want it I think you can still get one new, but it's not actively sold among the main distributors any longer, ie you don't find it in their price lists. When asking Paula at Linhof Studio why it was because it does not perform well enough together with 6um sensors. You can shoot it unshifted, but as soon as you shift some amount you'll get crosstalk artifacts, and that has disappointed so many buyers that they've decided not to sell it.

I've heard that the SK28 works alright on the legacy backs though, like my 33 megapixel Aptus. My widest lens is an SK35 so I haven't personally tested the SK28. I may get one in the future, the main problem with that is that my camera bag is full I don't have space for one more lens Smiley.

Yes for the recent backs it's the Rodenstock 23 and 28 one would recommend. With the SK28 you don't get any more usable image circle anyway, except for circumstances when heavy crosstalk doesn't hurt the picture too much, like an overcast sky or similar.

It's puzzling why Schneider designed the SK28 the way they did, the 6um backs was already available and sold when the lens was released in 2011 (P65+ was released 2008, P40+ 2009, Aptus-II 8 and 10 in 2010, IQ series 2011), so the should have known that it would not perform well on these backs. Maybe they thought that there was enough users with backs like P45+ and Aptus-II 7, or that it would soon arrive a new generation digital backs which was not so crosstalk prone, but that has not happened yet unfortunately.

As far as I can understand it's much less expensive to develop a large format lens of this type of design than a heavily retrofocus wide lens, simply because it's by nature a simpler design with a lot less glass. These lenses seem to almost be made to order as well, thus I guess it's not so big risk in designing a lens with such a narrow use case as the SK28 has. Otherwise Schneider has made a big mistake with this lens, released too late for the 9 and 7.2um backs, and too early for the current backs. If we're lucky the lens is still made or re-manufactured if/when we get new backs with new less crosstalk-prone sensor technology.
« Last Edit: August 19, 2014, 03:05:52 AM by torger » Logged
Ken R
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« Reply #15 on: August 19, 2014, 10:54:24 AM »
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Well, "semi-discontinued" I guess, if you really want it I think you can still get one new, but it's not actively sold among the main distributors any longer, ie you don't find it in their price lists. When asking Paula at Linhof Studio why it was because it does not perform well enough together with 6um sensors. You can shoot it unshifted, but as soon as you shift some amount you'll get crosstalk artifacts, and that has disappointed so many buyers that they've decided not to sell it.

I've heard that the SK28 works alright on the legacy backs though, like my 33 megapixel Aptus. My widest lens is an SK35 so I haven't personally tested the SK28. I may get one in the future, the main problem with that is that my camera bag is full I don't have space for one more lens Smiley.

Yes for the recent backs it's the Rodenstock 23 and 28 one would recommend. With the SK28 you don't get any more usable image circle anyway, except for circumstances when heavy crosstalk doesn't hurt the picture too much, like an overcast sky or similar.

It's puzzling why Schneider designed the SK28 the way they did, the 6um backs was already available and sold when the lens was released in 2011 (P65+ was released 2008, P40+ 2009, Aptus-II 8 and 10 in 2010, IQ series 2011), so the should have known that it would not perform well on these backs. Maybe they thought that there was enough users with backs like P45+ and Aptus-II 7, or that it would soon arrive a new generation digital backs which was not so crosstalk prone, but that has not happened yet unfortunately.

As far as I can understand it's much less expensive to develop a large format lens of this type of design than a heavily retrofocus wide lens, simply because it's by nature a simpler design with a lot less glass. These lenses seem to almost be made to order as well, thus I guess it's not so big risk in designing a lens with such a narrow use case as the SK28 has. Otherwise Schneider has made a big mistake with this lens, released too late for the 9 and 7.2um backs, and too early for the current backs. If we're lucky the lens is still made or re-manufactured if/when we get new backs with new less crosstalk-prone sensor technology.

Also the SK28mm is not exactly cheap. So its not like the design compromise resulted in a much more affordable extreme wide angle option for digital back users (compared to the Rodenstock HR-W lenses). However, I have seen some really nice results posted using 60mp backs (even shifted) so the lens does not seem to perform that bad on those backs. On the 80mp backs the performance seems much worse. Again, from what I have seen posted.
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torger
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« Reply #16 on: August 20, 2014, 02:12:38 AM »
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Also the SK28mm is not exactly cheap. So its not like the design compromise resulted in a much more affordable extreme wide angle option for digital back users (compared to the Rodenstock HR-W lenses). However, I have seen some really nice results posted using 60mp backs (even shifted) so the lens does not seem to perform that bad on those backs. On the 80mp backs the performance seems much worse. Again, from what I have seen posted.

The SK28 is ~$4.7k and has 90mm image circle, the Rodenstock Digaron-S 28mm is ~$6.4k and has 70mm image circle, and if you want 90mm IC as wide as you can get from Rodenstock you need the Digaron-W HR 32mm which is $7.6k (the 23 is $7.2k by the way, with 70mm image circle). So it depends on how you see it, no wide angle is cheap as it requires substantially larger glass diameter than a longer lens, but comparing these numbers I do find the SK28 substantially cheaper than the Digaron alternatives (the reason is that SK28 is a traditional large format design which does not require as many glass elements, and thus becomes cheaper). Note that you'd probably want center filter for it though, which adds a few hundred bucks, but some choose to shoot two exposures and merge instead. Center filters can be a pain in hard light (reflections).

I would not say SK28 is a compromised design, you could actually say it's rather the exact opposite. The Rodenstock Digarons are the compromised ones, they're made retrofocus (and thus with distortion) because digital sensors can't deal with real large format design, while the SK28 does not compromise that, it's made according to traditional large format design principles, but then unfortunately has to pay the price by that modern sensors are not so compatible with that. The Rodenstock Digarons represent the trend where "digital large format" becomes more and more similar and in the end same as mirrorless 135 cameras like the A7r only with more pixels, further on this trend is cameras like the Alpa FPS. I'm not particularly fond of that development.

Anyway, back to the SK28, if you reduce your expectation to say a 70-75mm image circle the SK28 is okay on a 6um back, so it can still be an alternative to the Digaron-S 28 which has hard limit on 70mm. I know Dan Lindberg uses the SK28 on a Credo60 with good results (he's not using the center filter if I remember correctly), but you need to work within the limits.

One should also keep in mind that the LCC algorithm really need to stretch it to get this good results (you can't just use any generic LCC algorithm, you need those that do specific fixes for Dalsa 6um which means C1 or Lumariver HDR), which affects dynamic range and post-processing robustness negatively, plus you get reduced color accuracy due to the crosstalk (a scene with muted colors suffers less than a scene with saturated colors). So yes you can get good results with it on 6um Dalsa, but you can't shift much and you may need to apply some of your post-processing magic.

The original question is if 6um Kodak does it any better or worse... still interested in knowing that. I just realized that Capture One probably doesn't have any LCC algorithm to deal with 6um Kodak (as there is no such product in the Phase One family) so it can be hard to compare, even if Kodak behaves better the end result may be worse due to there's no Kodak-specific hacks in the LCC algorithm. I can introduce that in Lumariver HDR if required though.
« Last Edit: August 20, 2014, 02:19:26 AM by torger » Logged
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« Reply #17 on: August 20, 2014, 07:00:26 AM »
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Torger,

If Phase C1 can open the file, I believe it will generate a LCC.  In my recent testing with the A7r and Arca DSLR2, I used the SK35, 40HR-W (Rodenstock), SK60, 90mm HR (Rodenstock).  Each of these lenses required LCC corrections, for all shots, center and shifts.  Capture One generated the LCC's with no problem.  Capture One supports the A7r raw, I think that the question, is will Phase One i.e. Capture One support the raw from the 50MP Kodak sensor you are interested in.  I am not sure which company uses this, I assume it's Leaf? which should be supported or Hasselblad, not sure if their raw is supported. 

Paul
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torger
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« Reply #18 on: August 20, 2014, 07:25:44 AM »
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Torger,

If Phase C1 can open the file, I believe it will generate a LCC.  In my recent testing with the A7r and Arca DSLR2, I used the SK35, 40HR-W (Rodenstock), SK60, 90mm HR (Rodenstock).  Each of these lenses required LCC corrections, for all shots, center and shifts.  Capture One generated the LCC's with no problem.  Capture One supports the A7r raw, I think that the question, is will Phase One i.e. Capture One support the raw from the 50MP Kodak sensor you are interested in.  I am not sure which company uses this, I assume it's Leaf? which should be supported or Hasselblad, not sure if their raw is supported. 

It's only(?) Hasselblad that has it, in the recently discontinued CFV-50, and in the H5D-50 of the current products. This makes the Kodak sensor really rare in tech cams, maybe there's no user in the whole wide world that has tested the combination of CFV-50 and SK28. As far as I know C1 don't open Hasselblad 3FR/FFF, but maybe if I convert to DNG? There's the additional issue that when casts get extreme you can get some additional artifact like the microlens ripple or tiling which is specific to the sensor technology used. C1 has implemented tiling and microlens ripple supression as Leaf and Phase One backs uses Dalsa which has these issues, but I assume that even if you succeed opening a 3FR in C1 there won't be any Kodak-specific LCC fixes to handle the extreme cases.

However I don't even know if there are any, possibly the Kodak sensor is designed differently so you don't get the ripple and maybe there's no tiling problem either. If that is the case, and also color cast is lower than I would be further attracted by this sensor. The big pain with the CFV-50 from my perspective is the next to useless screen, I prefer being able to check sharpness, especially in tilt/swing closer range photos. If the sensor is a lot better for the wides I like I might live with that though.
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