Luminous Landscape Forum
Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: yaya on October 24, 2006, 12:02:05 pm
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Hello everyone, the following statement has been published today on several online boards,
Best regards, Yair
Yair Shahar | Leaf EMEA | Regional Manager |
mob: +44 77 8992 8199 | yair.shahar@kodak.com
Cast Effects in Wide Angle Photography
Over the last few months, some image related issues involved in using high resolution Leaf backs with wide-angle, non-retrofocal lenses and camera movements, have been receiving considerable attention on various forums.
We have been thoroughly investigating the issue and would like to share what we have discovered. We want photographers to understand the problem and to appreciate the available solutions.
1. The problem is encountered mainly by our architectural customers, in the form of slowly changing and/or abrupt color cast differences across the image, almost always in cases where non-retrofocal, wide angle lenses are used.
2. Most photographers never encounter this problem. It requires specific optical equipment to recreate it.
3. The problem is a sensor problem. It is not restricted to a particular type of sensor but occurs in different forms in all sensors from high-end 39MP to low-end 3MP sensors. A technical primer about different cast effects and their possible causes can be found at http://www.leaf-photography.com/files/docs...Photography.pdf (http://www.leaf-photography.com/files/docs/techBulletin/Cast_Effects_in_Wide_Angle_Photography.pdf)
4. Leaf and its customers originally expected that the gray uniformity found in the Valeo 22 and the Leaf Aptus 22 would be preserved in the Leaf Aptus 75 and Leaf Aptus 65, despite the considerably smaller size of the pixel (52 sq mm. instead of 81 sq mm.). Gray uniformity is indeed preserved for regular retrofocal lenses where our competitors still suffer from non-uniformity.
5. However, in the wide angle, non-retrofocal domain, the Leaf sensors have not delivered the expected standard of gray uniformity. The problem is not with the abrupt cast change ("centerfold" line) which is a specific anomaly that we expect to solve but with the slowly changing cast effect. After considerable research and discussion, we have regretfully reached the conclusion that with current chip technology, image sensors will probably continue to produce cast for some wide angle lenses and camera movements.
6. The team at Leaf continues to investigate this problem from all aspects - electronic and optical - in search of an effective hardware solution. For now, we have developed and field-tested an initial, practical, software solution which enables the photographer to correct any cast effect, caused either by specialty lenses or by camera movements. The solution is comprehensive but requires some workflow effort. The software can be downloaded from
http://www.leaf-photography.com/pages/supp...n_Adjuster.aspx (http://www.leaf-photography.com/pages/support/Custom_Gain_Adjuster.aspx).
7. We are also working on further software solutions that will reduce the amount of effort required to correct the cast effects. These improvements will be made public as soon as they are ready.
We ask you to please take the time to read the technical bulletin and appreciate the nature of the problem and how it is being dealt with at Leaf. Any suggestions for improving the current solution or for new avenues of investigation are of course most welcome.
Thanks,
Stanley Barkan, Chief Scientist,
Leaf Products, Digital Capture Group
Leaf-Photography.com (http://www.leaf-photography.com)
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Thank you Yair for posting this statement.
I am one of the unfortunate owners of an Aptus75 which produces the centerfold line and color cast used with my Alpa XY and Schneider Digitar 24 / 35 lenses.
If I understand the statement correctly Leaf can get rid of the centerfold line (most likely by replacing my current back as it happened for other users with the same problem) but will not be capable of solving the cast problem at the hardware side. The only possibility for me would be to use the gain adjuster utility to get the clean files I could expect in return for a considerable investment. But even if this software works I would still have to consider my invest in Leaf, 'cause it would slow down my workflow quiet a bit.
If there is anyone on the forum using a phase one or imacon 39Mpix back together with an Alpa SWA / XY could you please indicate to me whether you guys experience similiar problems. This way I could base my decision to stick with Leaf or switch to another manufacturer on some more facts.
Frank
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If there is anyone on the forum using a phase one or imacon 39Mpix back together with an Alpa SWA / XY could you please indicate to me whether you guys experience similiar problems. This way I could base my decision to stick with Leaf or switch to another manufacturer on some more facts.
Frank,
While I don't own either alternate backs you have mentioned nor have I used the Alpa
I have used both on the Hasselblad ArcBody,which offers some tilt and shift possibilities,
and can assure you that the color cast (usually magenta/green) is present on both and requires
a similar sort of software 'intervention' clean the effect.
It is not particularly difficult but does add one more step in ones workflow. So,in short, if you
are happy with your A75,except for having to deal with colorcast,then you will realize no
advantage,in this regard,by considering another brand.
Mark
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The problem is not with the abrupt cast change ("centerfold" line) which is a specific anomaly that we expect to solve but with the slowly changing cast effect. After considerable research and discussion, we have regretfully reached the conclusion that with current chip technology, image sensors will probably continue to produce cast for some wide angle lenses and camera movements.
[a href=\"index.php?act=findpost&pid=81999\"][{POST_SNAPBACK}][/a]
So what is causing the centerfold ? Why is centerfold only seen on Leaf/Sinar ?
Edmund
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"4. Leaf and its customers originally expected that the gray uniformity found in the Valeo 22 and the Leaf Aptus 22 would be preserved in the Leaf Aptus 75 and Leaf Aptus 65, despite the considerably smaller size of the pixel (52 sq mm. instead of 81 sq mm.). Gray uniformity is indeed preserved for regular retrofocal lenses where our competitors still suffer from non-uniformity. "
its somehow brave to name your competitors here...... because after my understanding your DALSA competitors have found solutions which LEAF is still searching .... let me tell you the background for my statement:
what suprises me is that there is exatcly NO statement to the centerfold issue.... of course it's offset is subtracted in the recommended gain calibration software as well as any color cast offsets,- but this helps only to a certain amount, after my understanding this is not the solution to get rid of this issue, if you have a sensor which shows the centefold issue. Many dalsa 33mp sensors do so,- raise up the gradation enough and there will be situations where you might see it ,- not only with shift lenses!
after my experience and after my tests with various backs ( e75 sinar ) this issue is system immanent and can be eliminated only by a clever software solution. in the last months i was involved very closely in the developement of the programm of the eMotion DNG converter by stephan hess,- central point of this software was - beside the conversion to dng - the elimination of the "centerfold" issue. one other of eMotionDngs features is the elimination of color casts nd vignetting by using a calibration shot,- something Leaf does with the separate gain adjuster tool.
although i want to point out that we improved the eMotionDng programm to a tool with a highly automated batch workflow,- which is by far the fastest tool i have seen untill now,- allowing to convert hundreds of e75 and e22 files to dng without beeing involved,- if the source folder once is structured accordingly.
another big step is that stephan wrote a highlight recovery which is very effective till up to 2 stops in the highlights, compared to the original sinar software ( which is comparable to the leaf software in this ). it allows a far more relaxt shooting, because you can take much less care regarding blown hilights. eMotionDNG does not cut the information, if at least one color channel still is under 255, and even makes an edjucated guess when all channels exceed 255 -
the problem being to avoid color casts in extreme cases., most, probably all other existing mf software goes the most simple way,- doing nothing or blowing all channels up to 255.
i just finished my last shooting. 22 weeks in bangkok,- shooting the new bangkok airport. i started with the sinar e22 and changed after may to the e75,- and asked stephan to help me to make the e75 usable,- which means to deliver absolute neutral files without centerfold issues, and with a fast workflow- i am using wide angle shift lenses from 28 - 90mm beside h-blad tele lenses with 150+250mm. very important for me was a fast and practical workkflow...... from file numbering, over batch whiteshot processing to combining shots and respective whiteshot automatically when batchconverting the files.. i am excited about the resulting image quality,- its such a great step from the starting point where we have been in May thats its hard to believe that the same back has produced this....
it seems so that our starting point in May is more or less the point where leaf currently is,- so i would say its truly brave to point out the state of your competitors in LEAFs post above.
finally SINAR took over the parts of the software from stephan which bring solutions to the various sensor problems the dalsa 75 brought with it...... and everything`s fine now so far,- at least with the e75.
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Thanks for that explanation Rainer!
IOW all MFDB need some correction for non-retro wide-angles!
My question now is,could the Kodak sensor that used by Imacon and Phase ,be on the same
quality level as the Dalsa sensor that's being used by Leaf?
It's a well known fact that Phase has had their LCC in the Capture One software.
Maybe the P45+ is not such a bad option after-all?
I like the idea of longer exposure times and a higher ISO!
However the e-75 is still No1 on my shopping list.
Regards,
Willem.
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maybe Leaf should hire Stephan
Seriously though Rainer, I'm glad you've found a solution for your workflow. While I'm not thrilled to be using the plexi for Phase Lcc, it sure looks alot better with it than without. As someone stated previously (Mark?) it's another step in the workflow at this point.
Maybe at PhotoPlus all MFDB owners with Lcc issues can all meet under a big white plexi tent and have a beer while wearing special 3D glasses that are magenta in one lens and green in the other...after applying a BC (beer correction) profile everyone should be just fine.
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Rainer hi,
I am glad that Stepahn's clever tool is now working for you and that the results you are now getting are better than some of the ones shown printed in the booth at Photokina.
Our statement suggests that the current solution for color casts (and the centerfold is indeed an extreme case of cast, due to a certain chip design) is software based, much like Stephan's tool.
It also suggests that we will continue to work and finding a more elegant, effortless solution.
The Leaf Custom Gain Adjuster allows for removal of lens cast (inc. centerfold) and controlled removal of lens falloff, while saving the corrected files as either compressed or uncompressed, retaining all the necessary colour and tonal information, such as ICC input profile that cannot be carried by DNG.
These corrected files can be then taken back into Leaf Capture or any other RAW converter that supports our files for further adjustments/ editing/ processing.
Highlight recovery depends more on what the sensor records at the limit (in 14 or 16 bit) and how it translates to ink on paper in 8 bit (248 on the best RGB printer) then on just "making up" numbers. Your "conclusion" that the Leaf software is "comparable" to CaptureShop in this respect is somewhat mis-leading.
Yair
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Rainer hi,
I am glad that Stepahn's clever tool is now working for you and that the results you are now getting are better than some of the ones shown printed in the booth at Photokina.
Our statement suggests that the current solution for color casts (and the centerfold is indeed an extreme case of cast, due to a certain chip design) is software based, much like Stephan's tool.
It also suggests that we will continue to work and finding a more elegant, effortless solution.
The Leaf Custom Gain Adjuster allows for removal of lens cast (inc. centerfold) and controlled removal of lens falloff, while saving the corrected files as either compressed or uncompressed, retaining all the necessary colour and tonal information, such as ICC input profile that cannot be carried by DNG.
These corrected files can be then taken back into Leaf Capture or any other RAW converter that supports our files for further adjustments/ editing/ processing.
Highlight recovery depends more on what the sensor records at the limit (in 14 or 16 bit) and how it translates to ink on paper in 8 bit (248 on the best RGB printer) then on just "making up" numbers. Your "conclusion" that the Leaf software is "comparable" to CaptureShop in this respect is somewhat mis-leading.
Yair
[a href=\"index.php?act=findpost&pid=82069\"][{POST_SNAPBACK}][/a]
hi YAYA,
thank you for your flowers regarding my images at photokina,- for sure they would looked much better using an aptus22 not an emotion22..... dont you think so?
( anyway havent seen the prints myself cause i havent had time to be there,- some people told me they liked them,- maybe they also dont know the file quality which would have made your sensor. )
and about highlight recovery: you have not to make so much wind with your explanation,- just shot a file with the e75 and the same with the a75, devellop the raws with the eMotionDNG konverter and with the LEAF software and you will easily see what about i write,- or this time you could do what you recommended me last time: ask stephan about how he makes it possible that there is detail in his program where the others show pure and blownout white.
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Rainer,
I wasn't refering to the photographic qulaity of those prints since they were very pretty. However they did show some significant purple/ magenta/ green cast, which lead me to believe that they were from the "pre Stephan" period.
I apologize if I sounded offensive.
The test that you are suggesting is something that I do on a regular base with various systems and platforms.
One thing I can say is that no one has ever complained about lack of highlight detail on a Leaf back.
Respectfuly
Yair
Yair Shahar | Leaf EMEA | Regional Manager |
mob: +44 77 8992 8199 | yair.shahar@kodak.com
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well after all the beating up of Phase for their occasional LCC issue, I hope those same Leaf owners are now going to enjoy eating their hats over this one.
just tell me - sauteed or broiled with herbs?
I read the white paper and it STILL doesnt properly explain why there is a direct seam down the middle of the Leaf images. it explains why there is an LCC issue with true wide angle lenses, as we all knew, but no real explanation of the centrefold crease.
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Here is Stephan Hess's
Explanation (http://luminous-landscape.com/forum/index.php?showtopic=12581&view=findpost&p=80861) which in most parts is technically accurate.
Yair
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Here is Stephan Hess's
Explanation (http://luminous-landscape.com/forum/index.php?showtopic=12581&view=findpost&p=80861) which in most parts is technically accurate.
Yair
[a href=\"index.php?act=findpost&pid=82088\"][{POST_SNAPBACK}][/a]
I'd for one would be interested in which part it isn't accurate
Kind regards
Stephan
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In my experience, the P45 produces some lens cast with every lens, but the amount varies widely depending on lens quality and design.
When used with a Schneider 24mm digitar, there were strong and obvious (in the preview) blue/yellow and magenta/green shifts in the center and corners. This was effectively removed by the LCC tool, but you needed a reference shot for every set of captures.
When used with a Hassy V and CF lenses, there was also noticeable cast with every lens. Surprisingly, the most cast was produced by the 120 Makroplanar and 250 SA.
I kept my P45 but changed all my lenses. I now use HC lenses, which produce far less cast, and Rodenstock HRs, which are retrofocus. There is still some cast in every image, but one-time reference shots fix that. Use of the LCC tool is also necessary to get the correct white balance.
Phase gave me good support (after an initial lag) and eventually resolved my problem by allowing giving me a new H-back free of charge. But in my opinion, they were not forthcoming enough with their cutomers in communication and information sharing. They still won't admit that lens cast is a "problem".
I am impressed with Leaf for acting in such a forthright and honest manner. This is how you keep your customers even when there is an unexpected problem with your flagship product.
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I'd for one would be interested in which part it isn't accurate
Kind regards
Stephan
[a href=\"index.php?act=findpost&pid=82091\"][{POST_SNAPBACK}][/a]
You forgot to mention the RGB bayer pattern and the method being used for laying it on the pixels, which also "contributes" to this complexity
Cheers, Yair
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Rainer,
I wasn't refering to the photographic qulaity of those prints since they were very pretty. However they did show some significant purple/ magenta/ green cast, which lead me to believe that they were from the "pre Stephan" period.
I apologize if I sounded offensive.
Yair Shahar | Leaf EMEA | Regional Manager |
mob: +44 77 8992 8199 | yair.shahar@kodak.com
[a href=\"index.php?act=findpost&pid=82082\"][{POST_SNAPBACK}][/a]
Hi Yair,
thank you for clarifying, maybe i missunderstood you......
just for interest...: which of the images show this "significant purple/ magenta/ green cast" ?
here they are:
[attachment=1093:attachment]
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"which of the images show this "significant purple/ magenta/ green cast" ?"
# 1, 3, 4, and 6 show color casts.
-Just to be clear, the cast is not "significant", but present. I am also judging jpegs on a web browser. The pictures are amazing. I would love to have that opportunity. And in each case, the cast does not detract from the overall impact of the images. It is likely only a very anal architectural shooter would notice.
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"which of the images show this "significant purple/ magenta/ green cast" ?"
# 1, 3, 4, and 6 show color casts.
[a href=\"index.php?act=findpost&pid=82102\"][{POST_SNAPBACK}][/a]
color casts which are caused by any sensor shifts? i hardly doubt that..... more because all images are taken with the 22mp dalsa chip,- which has not suffered from the actual problems.
maybe you dont like my way of editing the images,- but sensor-caused colorcasts?
i would simply deny that.
the slight shift at the edges of image 1and6 is made by the 28HR, i think every lense with a fov as that shows some blueish-yellow cast,- at least an engeneer from schneider-kreuznach explained that to me some years ago, cause i phoned them to discuss the blueish - yellow casts which show the 4x5" wides from them ( all under 90mm,- it becomes very visible with the 57+47+37xl lenses ). its an optical law, no way to escape it,- although inverting, as phase always suggested with lcc and now also the dalsa sensors need with whiteref. shots inverts that casts also. but that has nothing to do with uneven sensor reproduction. these shots are not "treated" with whiterefernces.
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@yair
Sorry,
you implied that I wrote something which is not accurate, which implies I wrote something that is wrong.
Now you say I left something out, which is quite different.
By the way I didn't leave it out, I said "This has to do with the manufacturing process. Whatever the reason for having those areas is doesn't matter, important is that they exist."
This does not reduce the accuracy of my statement.
If anything it increases it, because the only information I have about the RGB Pattern thingie is from you. And I will not quote things I can't verify in a post in which I want to give information and not opinion.
Talking about opinions, here is one, so a big IMHO:
I've got the feeling your reaction to anybody who is of a different opinion is to try to discredit him, especially in a difficult situation as the one your in.
Your offhand "which in most parts is technically accurate" implying wrong information, without being able to proof it, is one such case.
Or trying to tell people that the images of a photographer are bad and when somebody asks, they are not bad, they suddenly have a cast. And when you look at the images there is no cast.
I've read some helpful and interesting posts from you, so I hope this all is a misunderstanding or a symptom of stress or probably it is just the so called language barrier.
@all
I apologize for wasting bandwidth on a rather personal matter.
But after having read the discussion about anonymity and the "higher worth" of information of people with "names" I think that especially members with "names", should be careful with their posts and should be aware of their responsibilty as opinion makers, and they should be told, if they seem to forget.
Kind regards
Stephan
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Hi Rainer,
I was editing my previous post to be a little more complete while you were replying at the same time. My Dalsa 22mp chip had color casts. Always subtle, always hard to spot. I often find that with the Dalsa 75 chip that I do not see the color casts until I have run the Custom Gain Adjuster and compare the images back and forth in the preview window of Bridge. Please don't take this as any kind of criticism. I feel most of my photos shot with the 22 sensor have a little cast here or there which no one else notices.
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Hi Rainer,
I was editing my previous post to be a little more complete while you were replying at the same time. My Dalsa 22mp chip had color casts. Always subtle, always hard to spot. I often find that with the Dalsa 75 chip that I do not see the color casts until I have run the Custom Gain Adjuster and compare the images back and forth in the preview window of Bridge. Please don't take this as any kind of criticism. I feel most of my photos shot with the 22 sensor have a little cast here or there which no one else notices.
[a href=\"index.php?act=findpost&pid=82106\"][{POST_SNAPBACK}][/a]
i was working with two 22mp dalsas,- one was looking completely even ( the one i used for the photokina shots ),- the other sensor has had a far more uneven color reproduction,- although still subtle.
therefore the first chip could not work without strong radial discolorations under fluorescent light sources ( i also saw this with kodak sensors ),- the second one ( which is my actual one ) renders fluorescent sources without any radial shifts.
so the sensors seem to act different, in its specs which are wide enough to bring that visible differences out. but..... just to remember......good old 4x5" shooting was not absolute "color-cast-free" also,- if one has used superwides under 90mm and good eyes or grey walls.
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"good old 4x5" shooting was not absolute "color-cast-free" also,- if one has used superwides under 90mm and good eyes or grey walls."
-absolutely, and I am very glad to be rid of this. I often did not realize the color casts in the 4x5 shots until I used scanning software to remove it.
I like the ability to produce images free of any color casts from the sensor, or the lenses, by using the Gain adjuster, whether it is Stephan's or Leaf's. The ability to remove light fall-off in the adjuster is also a very welcome change from having to use center filters.
As long as we are wandering off topic... How does your sensor respond to flourescent light? Do you use Input profiles specific to flourescent light souces? Do you create you own custom profiles? Just interested.
-Eric
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Rainer,
I wasn't refering to the photographic qulaity of those prints since they were very pretty. However they did show some significant purple/ magenta/ green cast, which lead me to believe that they were from the "pre Stephan" period.
Yair
Yair Shahar | Leaf EMEA | Regional Manager |
mob: +44 77 8992 8199 | yair.shahar@kodak.com
[a href=\"index.php?act=findpost&pid=82082\"][{POST_SNAPBACK}][/a]
Yaya,
I'd like to answer on this one, having seen myself the prints in question at Sinar's booth during Photokina. I must say that I wonder why you are first stating that the images have a problem, than all of a sudden claiming (and misleading readers) that there is a noticeable green/magenta color cast: where could you notice any green/magenta color cast in these prints?! They are absolutely "neutral", from one side to the other, and am pretty sure that a RGB info would show that there is neither a magenta nor green cast, rather a blueish/yellowish cast, which HAS NOTHING to do with our SENSOR issues, but is directly related to the lens/optical.
I have to say here, that I am using the eMotion 75 as well, and the tools provide by Stephan Hess for the Captureshop files are just fantastic, with a speedy worklow which isn't less (fantastic)! Such centrefold and color casts issues are definitively the past with the eMotion backs.
What surprises me, is your statement about the competition, which is unfair and out of the blue, without any serious prove. Is that just to discredit the competition? In my opinion it is not the right way to solve one's own problems. As Rainer puts it rightly: just make a side by side test between the eMotion 75 and the Aptus 75, and your eyes will open. As I said in a previous post: often one does not see a color cast in a file, when not compared side by side with the same file corrected. Only when one has the 2 files side by side can the difference be noticed: I am saying this by experience.
What surprises me even more, is like Rainer says, that there is absolutely NO clear statement on the centrefold issue and more important, that you are stating in your post that this happens only with shifted situations: absolutely wrong, as mentioned by Rainer. Just push a bit your tonal curve and you may see it clearly, and not only with WA lenses, as stated. Just shoot on a neutral grey background and see the result.
Aon
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Yaya,
I'd like to answer on this one, having seen myself the prints in question at Sinar's booth during Photokina. I must say that I wonder why you are first stating that the images have a problem, than all of a sudden claiming (and misleading readers) that there is a noticeable green/magenta color cast: where could you notice any green/magenta color cast in these prints?! They are absolutely "neutral", from one side to the other, and am pretty sure that a RGB info would show that there is neither a magenta nor green cast, rather a blueish/yellowish cast, which HAS NOTHING to do with our SENSOR issues, but is directly related to the lens/optical.
I have to say here, that I am using the eMotion 75 as well, and the tools provide by Stephan Hess for the Captureshop files are just fantastic, with a speedy worklow which isn't less (fantastic)! Such centrefold and color casts issues are definitively the past with the eMotion backs.
What surprises me, is your statement about the competition, which is unfair and out of the blue, without any serious prove. Is that just to discredit the competition? In my opinion it is not the right way to solve one's own problems. As Rainer puts it rightly: just make a side by side test between the eMotion 75 and the Aptus 75, and your eyes will open. As I said in a previous post: often one does not see a color cast in a file, when not compared side by side with the same file corrected. Only when one has the 2 files side by side can the difference be noticed: I am saying this by experience.
What surprises me even more, is like Rainer says, that there is absolutely NO clear statement on the centrefold issue and more important, that you are stating in your post that this happens only with shifted situations: absolutely wrong, as mentioned by Rainer. Just push a bit your tonal curve and you may see it clearly, and not only with WA lenses, as stated. Just shoot on a neutral grey background and see the result.
Aon
[a href=\"index.php?act=findpost&pid=82131\"][{POST_SNAPBACK}][/a]
The competition is clearly about the backs with the Kodak sensors versus the Dalsa sensors. The original post could not be comparing the Leaf back to the eMotion backs, because the eMotion backs do not suffer from the color uniformity issues with retro-focal lenses which the post addresses.
There is no clear statement on the Centerfold issue???? How bout this one from the first post:
"("centerfold" line) which is a specific anomaly that we expect to solve"
It could not be anymore clear.
As for the prints at Kina. I assume that Yair was saying someting about the prints that he felt Rainer would agree with. We are in the Dalsa boat together. I would give Yair some empathy and understanding here. He is one of the most respectful and helpful posters on Luminous Landscape.
To make an objective judgement on the print issue I will need Rainer to send me several of these large prints so that I can make a closer, long term evaluation
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The competition is clearly about the backs with the Kodak sensors versus the Dalsa sensors. The original post could not be comparing the Leaf back to the eMotion backs, because the eMotion backs do not suffer from the color uniformity issues with retro-focal lenses which the post addresses.
There is no clear statement on the Centerfold issue???? How bout this one from the first post:
"("centerfold" line) which is a specific anomaly that we expect to solve"
It could not be anymore clear.
As for the prints at Kina. I assume that Yair was saying someting about the prints that he felt Rainer would agree with. We are in the Dalsa boat together. I would give Yair some empathy and understanding here. He is one of the most respectful and helpful posters on Luminous Landscape.
To make an objective judgement on the print issue I will need Rainer to send me several of these large prints so that I can make a closer, long term evaluation
[a href=\"index.php?act=findpost&pid=82134\"][{POST_SNAPBACK}][/a]
Dear Eric,
With all my respect, in my opinion, the centrefold issue is not clearly addressed in the Leaf statement, rather aknowledged that it is a fact.
Also, for me, stating that "...where our competitors still suffer from non-uniformity" is implying that ALL competitors suffer from it, included the Sinarbacks eMotion. Which is simply un-true and misleading other photographers. As an eMotion user, it is my right to give answer to this, despite the fact that Yaya is a respected poster. I don't think that Sinar has ever posted and spoken against Leaf or other competitors: at least I have never read such. It is one thing to inform one's own customers in a correct way and another thing to claim about the competition, IMO.
Rainer's files: I share the opinion with Stephan, that the judgment of the files by Yaya have been made with the purpose to mislead the readers. Any neutral judgment of these prints would say the contrary, that they are perfect concerning the color cast sensor issue. I agree that you need to have the files in front of you and I myself had it handed-over by Rainer: that is the only reason why I am claiming that they are perfect, with no Magenta/Green cast in it.
But as said, this is only my own opinion.
Aon
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"good old 4x5" shooting was not absolute "color-cast-free" also,- if one has used superwides under 90mm and good eyes or grey walls."
-absolutely, and I am very glad to be rid of this. I often did not realize the color casts in the 4x5 shots until I used scanning software to remove it.
I like the ability to produce images free of any color casts from the sensor, or the lenses, by using the Gain adjuster, whether it is Stephan's or Leaf's. The ability to remove light fall-off in the adjuster is also a very welcome change from having to use center filters.
As long as we are wandering off topic... How does your sensor respond to flourescent light? Do you use Input profiles specific to flourescent light souces? Do you create you own custom profiles? Just interested.
-Eric
[a href=\"index.php?act=findpost&pid=82119\"][{POST_SNAPBACK}][/a]
same experience than me about 4x5".... and the digital files which are corrected with inverted whiteshots are really impressive.
some post above wrote about if the dalsa users should not eat our hats about the fact that we need now a similar worflow tham phase? usually i dont wear or eat any hats,- but you are right,- me i was complaining a lot of about phase and their colorshifts,- and have to admit now that for my purposes its not a great deal to shoot white referemces, and after i started to appreciate this completely even and grey-uniform files i get out of my lenses,- now i do even the same if i use the e22 which would not need that treatment so urgent...
BUT ,- how big is that deal depends very much how easy makes the software the handling of the files in pp, and also how clever is the software inverting ( esp. here how are treated the white files ) and subtracting. we tested version after version of the eMotionDNG konverter till the quality of the inversion has met our expactations,- stephan was writing incredible fast update after update ( maybe 20 - 30 or so,- just for the white ref. "treatment"... ).
these ways to treat the whiteref.files have big impact to the final image quality,- it would lead too much to go into this here ( and stephan could do that far better than me ),- best thing is to try it out and to compare the images. at the moment i think there might be a bigger difference in the resulting quality than one should expect.
about phase: i dont know enough about the p45. after my understanding there are some advantages from the dalsa sensors... a.e. the handling of backlighted objects or of fine branches or trees ( purple fringing ),- but it could be that i am wrong here and that these "old" kodak problems are solved with the p45. i havent tried one,- but i am 100% that the phase backs wlll deliver also 1.class quality in the right hands.
about fluorescent lights:
i am amazed by the quality the e75 delivers here, and also under mixed light sources.
it is the greatest advantage over the 22 sensor for architecture or interior shooters i.m.o....
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Wow!
I thought I would trow in my 2CW.
For an architectural shooter like me,who is about to purchase a MFDB ,it's getting more confusing by the minute.
First it was the Dalsa sensor that would get rid of all the problems that arose with the Phase backs,but like Rainer said,all sensors (Kodak and Dalsa) need some kind of correction before the exposure and after.
It's clearly now even more important to check the work-flow and relevant processors from Leaf,Sinar and Phase.
I think Rainer is certainly on the right track with the e-75 with the help of Stephan Hess.
BTW great shots of the airport Rainer!
However I might beginning to think that the P45+ with the C1 V4 might be an option as well.
At the end of the day,a fashion/portrait shooter might prefer a different back than an architectural shooter.
Same for a still-life guy with a tilt/shift camera.
I am curious how Michael Kravit managed to get a replacement Aptus-75 that shows no color-shifts or centerfold issues with his 24-35 and 47 Schneiders?
Happy shooting !
Willem.
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Hi Rainer
Thanks for sharing your superb photos. At the end of the day all this digital stuff is just a tool to make/take photos. I think we sometimes get too carried away with all the technical stuff and forget about the images.
thanks Ivan
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Totally correct Ivan!
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I am curious how Michael Kravit managed to get a replacement Aptus-75 that shows no color-shifts or centerfold issues with his 24-35 and 47 Schneiders?
Willem.
[a href=\"index.php?act=findpost&pid=82143\"][{POST_SNAPBACK}][/a]
Like Rainer says:
"i was working with two 22mp dalsas,- one was looking completely even ( the one i used for the photokina shots ),- the other sensor has had a far more uneven color reproduction,- although still subtle.
therefore the first chip could not work without strong radial discolorations under fluorescent light sources ( i also saw this with kodak sensors ),- the second one ( which is my actual one ) renders fluorescent sources without any radial shifts."
So what about quality control? Maybe we should test half a dozen backs of the exact same model, and then decide which one to buy? Does any dealer even have that many backs in stock?
Or complain loud and long, like Michael Kravit and Boghb did.
Kumar
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Like Rainer says:
"i was working with two 22mp dalsas,- one was looking completely even ( the one i used for the photokina shots ),- the other sensor has had a far more uneven color reproduction,- although still subtle.
therefore the first chip could not work without strong radial discolorations under fluorescent light sources ( i also saw this with kodak sensors ),- the second one ( which is my actual one ) renders fluorescent sources without any radial shifts."
So what about quality control? Maybe we should test half a dozen backs of the exact same model, and then decide which one to buy? Does any dealer even have that many backs in stock?
Or complain loud and long, like Michael Kravit and Boghb did.
Kumar
[a href=\"index.php?act=findpost&pid=82152\"][{POST_SNAPBACK}][/a]
maybe they would cost again the double if selected with more narrow specs....
furthermore it would have been hard to say which sensor was finally the better one,-
cause each one has had its advantages..
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Hello all, again,
I've posted this official statement in order to fulfil a request made by the *public* ever since the initial reports about the centerfold came out.
Such public statements are not a regular event in our industry and I think we will all agree that my agenda here is clear and well stated.
In all fairness, I did not intend to let it develop into a grilling party, although some members of this board, guided by other agendas, would probably love to see this happening.
If I pass any judgement over image quality, this is based on several years of pixel digging, literally and I will do it both internally in Leaf and externally with the competition.
Still this is not supposed to become personal and if anyone is being personally offended, then I apologize all heartedly.
I say we follow Ivan's suggestion and let this topic rest. Anyone who's still after clarifications or additional info, can contact me directly or our support team.
Thanks, yair
[span style=\'font-size:8pt;line-height:100%\']Yair Shahar | Leaf EMEA | Regional Manager |
mob: +44 77 8992 8199 | yair.shahar@kodak.com
[/span]
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Hello all, again,
I've posted this official statement in order to fulfil a request made by the *public* ever since the initial reports about the centerfold came out.
Such public statements are not a regular event in our industry and I think we will all agree that my agenda here is clear and well stated.
In all fairness, I did not intend to let it develop into a grilling party, although some members of this board, guided by other agendas, would probably love to see this happening.
If I pass any judgement over image quality, this is based on several years of pixel digging, literally and I will do it both internally in Leaf and externally with the competition.
Still this is not supposed to become personal and if anyone is being personally offended, then I apologize all heartedly.
I say we follow Ivan's suggestion and let this topic rest. Anyone who's still after clarifications or additional info, can contact me directly or our support team.
Thanks, yair
[span style=\'font-size:8pt;line-height:100%\']Yair Shahar | Leaf EMEA | Regional Manager |
mob: +44 77 8992 8199 | yair.shahar@kodak.com
[/span]
[a href=\"index.php?act=findpost&pid=82158\"][{POST_SNAPBACK}][/a]
hi yair again,
without having any wish to eat you ( also for suggestion problems for human meat since several months),- and without wanting to be unfair to you..... but as stephan said before,- maybe in parts its a language problem,- but aside this it could be also that you or your company provocate a little bit to be attacked, simply for the way how you speak or how you use words which- at least - i interpretated as personal attacks.
so again in this post you apologize that , but immediately you start yout next offense, if you write about some people who are guided by other agendas. you speak about me? if not everythings fine,- if so, i want to tell you that i am not guided by any company.....,- although my good connect to sinar after the last year of shooting is obvious,- 1. because they took over images from me for their advertisement purposes and 2. because they have been opened enough to take over stephans and my investments in a working software solution for the dalsa sensor, which is built in the e75..... i like that and i have my benefit from that,- but i am far away to atttack you or your company because you are a leaf rep, and i am far away to let me "guide" by some company.
i apologize if i took your first comment to my photokina shots a little bit too personal.... but i took it with some humor, didnt i? , so was my answer( i still dont see the casts you are seeing ).
i spent a huge amount of my time cooperating with stephan on the solution of exactly the problems you are naming and having, instead of trying to get one replacement sensor after the other.- LEAF was allways in my eyes for going in your system also, before i finally went with SINAR....
so sorry me that i read carefull if you found now a solution for the cf issue or not..... i just got disappointed, thinking i interpretated your statement very well, maybe for knowing something about the flaws you are fighting with and where it seems you are now herein,- but than you tell in the same post that your "competitors" were still behind leaf..... i think thats simply not good style, or at least i dont like it that much.
also its not so far to think that you speak about sinar here.
the problems with the kodak sensors are reallly very different to the dalsas,- and also there are several plus points for phase, so it doesnot sound that logic just to say they are behind...
no idea about the imacons. i didnt liked their marketing of their scanners too much cause they name then "drumscanners" and they are not ( so i prefered my real drumscannner over their products )..... thats all i know about that brand.
so i will shut up now here as you were recommending....
have a nice day,- dont take it personal, it is not.
rainer
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hi yair again,
without having any wish to eat you ( also for suggestion problems for human meat since several months),- and without wanting to be unfair to you..... but as stephan said before,- maybe in parts its a language problem,- but aside this it could be also that you or your company provocate a little bit to be attacked, simply for the way how you speak or how you use words which- at least - i interpretated as personal attacks.
so again in this post you apologize that , but immediately you start yout next offense, if you write about some people who are guided by other agendas. you speak about me? if not everythings fine,- if so, i want to tell you that i am not guided by any company.....,- although my good connect to sinar after the last year of shooting is obvious,- 1. because they took over images from me for their advertisement purposes and 2. because they have been opened enough to take over stephans and my investments in a working software solution for the dalsa sensor, which is built in the e75..... i like that and i have my benefit from that,- but i am far away to atttack you or your company because you are a leaf rep, and i am far away to let me "guide" by some company.
i apologize if i took your first comment to my photokina shots a little bit too personal.... but i took it with some humor, didnt i? , so was my answer( i still dont see the casts you are seeing ).
i spent a huge amount of my time cooperating with stephan on the solution of exactly the problems you are naming and having, instead of trying to get one replacement sensor after the other.- LEAF was allways in my eyes for going in your system also, before i finally went with SINAR....
so sorry me that i read carefull if you found now a solution for the cf issue or not..... i just got disappointed, thinking i interpretated your statement very well, maybe for knowing something about the flaws you are fighting with and where it seems you are now herein,- but than you tell in the same post that your "competitors" were still behind leaf..... i think thats simply not good style, or at least i dont like it that much.
also its not so far to think that you speak about sinar here.
the problems with the kodak sensors are reallly very different to the dalsas,- and also there are several plus points for phase, so it doesnot sound that logic just to say they are behind...
no idea about the imacons. i didnt liked their marketing of their scanners too much cause they name then "drumscanners" and they are not ( so i prefered my real drumscannner over their products )..... thats all i know about that brand.
so i will shut up now here as you were recommending....
have a nice day,- dont take it personal, it is not.
rainer
[a href=\"index.php?act=findpost&pid=82160\"][{POST_SNAPBACK}][/a]
well said, Rainer
No need to say that I've felt myself as well concerned by the statement "some people who are guided by other agendas". It seems to me that is it impossible to post here when being a Sinarback user, without being automatically "attacked" by some others. I am asking myself what the precise agenda of these persons are?
I would prefer a forum where technical posts remain what they should be: an information source for other photographers encountering the same or similar problems. Speaking about the competition is fair enough, but not claiming out of the blue and without any prove and with the obvious sole reason to mislead.
Aon
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Hi all,
As someone who would like to get a MFDB I have taken a close interest in all the postings on the colour cast and centrefold issues. Maybe someone could clarify why on some models one back will show the faults and another won't. It can't be just a wideangle problem because from what I read other lenses have been giving the problems too. Is it a quality control problem? If so, that's just astonishing considering the cost of these things. I know these backs are cost effective over a period if you're used to shooting tons of film, but I get the feeling certain manufacturers feel it's nitpicking and annoying to bring these problems to their attention. Hence their reluctance to sometimes even acknowlege them.
All I can say is the manufacturers are not helping themselves by this attitude and I'm sure there are many photographers out there, who like me are reading all this, making notes and are dubious about taking the plunge. If the back makers want to stay alive then I think they should get their act together and start valuing their customers, present and future.
My two cents too.
Barrie Watts
www.barriewatts.co.uk
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I am curious how Michael Kravit managed to get a replacement Aptus-75 that shows no color-shifts or centerfold issues with his 24-35 and 47 Schneiders?
Willem.
[a href=\"index.php?act=findpost&pid=82143\"][{POST_SNAPBACK}][/a]
Willem,
I was very persistent with Leaf and waited over 9 weeks for the replacement.
The back I received last week shows absolutely no centerfold with my Digitar 24, 35 and 47 lenses.
As far as I can see, and my vision is not that great, there is no objectionable color shift while using these lenses. Leaf has told me that Dalsa has been working hard to implement engineering revisions with each delivery of new chips.
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Willem,
I was very persistent with Leaf and waited over 9 weeks for the replacement.
The back I received last week shows absolutely no centerfold with my Digitar 24, 35 and 47 lenses.
As far as I can see, and my vision is not that great, there is no objectionable color shift while using these lenses. Leaf has told me that Dalsa has been working hard to implement engineering revisions with each delivery of new chips.
[a href=\"index.php?act=findpost&pid=82247\"][{POST_SNAPBACK}][/a]
Hmm, if there is no color shift even with the 24 then people will be falling over each other to get one !
Edmund
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Hmm, if there is no color shift even with the 24 then people will be falling over each other to get one !
Edmund
[a href=\"index.php?act=findpost&pid=82257\"][{POST_SNAPBACK}][/a]
For a bright guy you need to pay more attention Edmund.
He did NOT say there is no color shift, he said to his eye there is no OBJECTIONABLE color shift.
BTW, which MFDB are you using for your work?
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For a bright guy you need to pay more attention Edmund.
He did NOT say there is no color shift, he said to his eye there is no OBJECTIONABLE color shift.
BTW, which MFDB are you using for your work?
[a href=\"index.php?act=findpost&pid=82285\"][{POST_SNAPBACK}][/a]
Well, name one single analog film ( yes film, not lens ) which does not produce colour shift to a certain degree.
That there appears to be a chance of getting a Dalsa equipped back without the centerfold issues sounds pretty good to me.
Leaf has told me that Dalsa has been working hard to implement engineering revisions with each delivery of new chips.
[a href=\"index.php?act=findpost&pid=82247\"][{POST_SNAPBACK}][/a]
----> Yair : Thanks a lot for posting the statement; could you tell us about possible improvements made by Dalsa in the recent past to correct the centerfold problems, as reported by Michael K. ?
Thanks again,
Tom
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----> Yair : Thanks a lot for posting the statement; could you tell us about possible improvements made by Dalsa in the recent past to correct the centerfold problems, as reported by Michael K. ?
Thanks again,
Tom
[a href=\"index.php?act=findpost&pid=82299\"][{POST_SNAPBACK}][/a]
I would be interested in hearing this as well.
Also I heard in NY today from a couple of guys in one of the retailers showrooms that Leaf will be issuing new firmware upgrade in the next two weeks that will solve the color cast issues.
The talk was that the combination of the centerfold solution and color cast firmware upgrade may give Leaf the cleanest image of all the MFDB's.
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could you tell us about possible improvements made by Dalsa in the recent past to correct the centerfold problems, as reported by Michael K. ?
At this point I cannot add any further information, sorry...
Yair
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I would be interested in hearing this as well.
Also I heard in NY today from a couple of guys in one of the retailers showrooms that Leaf will be issuing new firmware upgrade in the next two weeks that will solve the color cast issues.
The talk was that the combination of the centerfold solution and color cast firmware upgrade may give Leaf the cleanest image of all the MFDB's.
[a href=\"index.php?act=findpost&pid=82301\"][{POST_SNAPBACK}][/a]
My H2D39 has had no centrefold issues and I beleive the Kodak sensor is also made up of two parts a la Dalsa.
Casts I can't comment on as I don't have anything wider than an 80mm!!
Jo s. x