IQ160 tiling issue

[gerald.d]

It's a bit hard to produce such a list for technical wide angles, as it's not an on/off thing, and there's a lot of "it depends". I guess that's why there's no widely available list.

The clear statement though is that there is such a thing.

There are supported lenses where, if you get problems such as the ones being discussed in this thread, "then it's a warranty issue that should be followed up with your dealer."

I use three different Phase One backs, and use lots of different lenses on them. It would be useful to know which lenses are officially supported on which backs, so that I could identify when/if I have an issue that is supposed to be dealt with under warranty.

Perhaps it's the list that appears in the Lens Correction Profile drop-down in Capture One?

But if that's the case, then not a single tech lens is supported, and yet tech cam owners are being strongly urged to use Capture One and not Lightroom.

Personally, I'd far rather use Capture One than Lightroom and am generally extremely happy with the way it works. If this investigation leads to Phase One fixing some apparent bugs - despite the fact those bugs are occurring with unsupported lenses, then that can only be a good thing.

Doug would seem to be implying that the underlying issue is use of unsupported lenses. Personally, one of the defining USP's of the three Phase One digital backs that I use on a regular basis is that I can use them with a wide variety of lenses.

The 17 TSE may well not be supported, but if it wasn't possible to use it with the IQ250, then the IQ250 would never have been purchased.

You would appear to have identified a bug in the way the file I sent you is processed by Capture One.

It would be great if that bug could be fixed, because that bug IS the underlying issue.

 

[Pemihan]

Well, as stated earlier I'm having the issue with lenses like the 80mm LS and 120mm macro on DF+ and I would think those lenses are on the "supported list" ;-)

Also having the issue on my Cambo and Rodie 40HR which I just got as replacement for my SK35XL.
The 40HR should be on the supported list as well, at least I was told to get Rodies for wides in order to not have issues.

As a side not I can tell that with my Aptus-II 7 on tech cam I also often have issues in Capture One, even after applying LCC whereas in Leaf Capture there's usually none at all.

Peter

 

[dougpeterson]

As far as I'm aware the only Phase One provided list is here:
Knowledge base for Phase One and Mamiya Leaf users

As you can see it has not been updated in a while, as primary support for Phase One is deferred to the dealer network.

You can find our list on our Tech Camera Overview page which is based on extensive in house testing and extensive feedback from our large base of tech camera customers.

A great example of an unsupported lens+back combo is the 35XL with the IQ180. This [back+lens] combo is not supported and residual color cast or tiling experienced when using that combo is not a warranty issue.

We don't sell Alpa and don't maintain a list of compatible dSLR lenses, but if we did the 17TS would be listed as compatible.

 

[gerald.d]

We don't sell Alpa and don't maintain a list of compatible dSLR lenses, but if we did the 17TS would be listed as compatible.

Ok, so this is great news. The Canon 17mm TS-E is a supported lens for Phase One backs.

"If you are not getting excellent results (i.e. good color, no ripples, no tiling) with supported lenses in C1 with a proper LCC then it's a warranty issue that should be followed up with your dealer. The solution is not to switch to LR to mask the underlying issue, the solution is to eliminate the underlying issue."

Clearly an LCC with this lens is not something that many people could accomplish.

Taking that into consideration, would it be correct to surmise that, if one were to get unacceptable tiling issues in Capture One, that do not exist when processing with Lightroom, then the underlying issue is indeed what has been discussed all along - a bug in Capture One?

 

[dougpeterson]

I would recommend following up with your dealer to examine the issue you are having.

 

[gerald.d]

I would recommend following up with your dealer to examine the issue you are having.

I did.

That file was created after my back had been sent to Copenhagen for recalibration.

Phase One's response through my dealer after examining the file was "Shift with wide angle can exasperate the situation due to the angle of light. Some lenses are not recommended for this reason."

So perhaps you can understand why I would agree with torger's assessment that there is a bug in the way that Capture One is processing this file. After all, I don't get the same problem when processing with Lightroom.

Kind regards,

Gerald.

 

[torger]

It can be a long distance from dealer to software developer. I'm sure if the person that has written C1's LCC algorithm got Gerald's file he or she would in a couple of hours find out what the problem is. It's not rocket science for one who has the right knowledge.

The dealer/support chain is supposed to not involve developers though unless absolutely necessary, which means that in order for something to happen the support chain must figure out by themselves that it is a software problem that should be filed as a bug report. If they take in the back and run it through the standard tests it will probably pass, which is probably why nothing happens. I wonder if Phase One office ever got Gerald's file for analysis, or if it just bounced at the dealer?

The TS-E 17 is a strongly retrofocus lens, there should be no wide-angle tech lens issues at all with that lens. If a lens has no visible color cast you should not expect issues.

That a file works in Lightroom but not in C1 makes a pretty strong case that there's a bug.

 

[torger]

I've investigated some Aptus-II 10 files too, and an interesting property of that Dalsa sensor is that the major horizontal tile line on that sensor is not a line, it's a comb, as shown in attached picture (2x pixel peep on blue channel with strongly enhanced contrast). The advantage of this is that it's less visible, the disadvantage is that it's harder to cancel out. The sensor has "normal" tile lines too, so I don't know why the middle one was made like a comb, probably something special about the manufacturing process.

Currently C1 doesn't handle (at least some) Aptus-II 10 files too good, tiling on some of the normal tile edges become very visible (while again it works well enough in Lightroom). In that case it's even more obvious that C1 has some bug.

 

[Paul2660]

I have seen the "ripple" effect with both the 160 and now 260. This is with mainly the SK35 on shifts of more than 6mm.

I used the 160 for over a year and did not notice I was getting it, however on a shot I took in the fall of 2013 where I was shifting in low light 15mm with the SK43, I saw it in spades. I was also using the 40mm Rod (testing) and did not see this problem, so I figured it was an issue with the 43SK and IQ260.

I inquired with DT and they confirmed this, and also stated that the LCC should remove it in post.

When I worked up the 43mm shot, the LCC (when processed no loaded in C1) did removed most of it, however some was still present. The 40mm shot was much cleaner.

I then went back over some of my shots from 2013 and started to find places where I had gotten this, just not noticed it since I did not have a sky or solid color involved. Again worst offender was the SK35, with a few problems from time to time with the SK43.

I did find a series in brighter light, that C1 (7.2) would not totally resolve the issue with some shots taken with the SK35. The issue was mainly in a shot that was around 9mm of shift which is pushing that lens too much on a 160-260. There was enough loss of color saturation that the portion of the image that had it the worse was cropped.

However both 160 and 260 can show this problem at times.

I can't see how the Canon 17mm TS-E would get it since it's out so much further from the sensor, however I would figure that you could take an LCC just like on a tech camera and apply it? I have never tried this but had though of doing it just to help with the light fall off. One of these day's I may try it with my 24mm TS-E II on a 6D.

I have never opened any of my shots from the tech camera in LR as I don't prefer their LCC process (tried it but never could figure it out). However it's interesting that the problem files open clean in LR (the ones from the DF).

Paul

 

[torger]

It should be said that while I've recently seen a number of cases where LR works and C1 does not, there are also cases when C1 suppresses tiles better than LR does, and I assume that is the normal case.

I don't think LR's LCC algorithm supports suppressing microlens ripples.

 

[gerald.d]

I have seen the "ripple" effect with both the 160 and now 260. This is with mainly the SK35 on shifts of more than 6mm.

I used the 160 for over a year and did not notice I was getting it, however on a shot I took in the fall of 2013 where I was shifting in low light 15mm with the SK43, I saw it in spades. I was also using the 40mm Rod (testing) and did not see this problem, so I figured it was an issue with the 43SK and IQ260.

I inquired with DT and they confirmed this, and also stated that the LCC should remove it in post.

When I worked up the 43mm shot, the LCC (when processed no loaded in C1) did removed most of it, however some was still present. The 40mm shot was much cleaner.

I then went back over some of my shots from 2013 and started to find places where I had gotten this, just not noticed it since I did not have a sky or solid color involved. Again worst offender was the SK35, with a few problems from time to time with the SK43.

I did find a series in brighter light, that C1 (7.2) would not totally resolve the issue with some shots taken with the SK35. The issue was mainly in a shot that was around 9mm of shift which is pushing that lens too much on a 160-260. There was enough loss of color saturation that the portion of the image that had it the worse was cropped.

However both 160 and 260 can show this problem at times.

I can't see how the Canon 17mm TS-E would get it since it's out so much further from the sensor, however I would figure that you could take an LCC just like on a tech camera and apply it? I have never tried this but had though of doing it just to help with the light fall off. One of these day's I may try it with my 24mm TS-E II on a 6D.

I have never opened any of my shots from the tech camera in LR as I don't prefer their LCC process (tried it but never could figure it out). However it's interesting that the problem files open clean in LR (the ones from the DF).

Paul

An LCC with the 17 TSE would be tough to pull off due to the front element of that lens.

If anyone has a curved LCC plate that could be used, I'd be more than happy to buy it off them!

Kind regards,

Gerald.

 

[weinlamm]

If anyone has a curved LCC plate that could be used, I'd be more than happy to buy it off them!

Kind regards,

Gerald.

For what do you need a curved LCC-plate? It must be possible to use the 17mm Canon with a Lee Filter-holder:

DIY Canon TS-E17mm filter holder - YouTube
(and part II)

or
LinsenSchuss.de - Fotografie von Dane Vetter | Hobby Fotograf aus Jestetten - Canon TS-E 17mm f/4L Filterhalter
(but this is in german)

And if you could mount the Lee-holder you would have different options: the Lee front cap or perhaps a 45% plexiglas (I use this) or changing the Filter Guides to a wider version (possible is 1, 2 and 4mm), so that you can use your own LCC-card.

There's actually no system directly from Lee like the SW-150 for the Nikon 14-24, but if you have some time to craft, it should be possible.

 

[gerald.d]

Neither of those are designed taking into account when the lens is used on a MFDB. You'd get significant vignetting unfortunately.

Something like this might work though...

(frosted glass lamp shade)

 

[cly]

Gerald, I'd experiment with acrylic balls as used for decoration:

http://www.decowoerner.com/en_GB/Acrylic-balls-1-4767.2.html

Not sure if you get them in white. If not, you would have to try a small sandblaster.

Chris

 

[Landscapelover]

Peter,

I think it is a common problem. Several people have had similar problem.
I bought a brand new IQ180 when it first came out and had to change to a new one which continued having problems off-and-on especially with B&W. I was told it was caused by the border of sensor stitching.
It's more prominent in the sky and with B&W especially after contrast adjustment.
You are not alone. I would contact the dealer and have the back calibrated or changed.

Pramote

 

[Pemihan]

Pramote,

Thanks, I'm in the process of getting it sorted out. Will let you know of the outcome..

Peter

 

[torger]

Done some extensive testing with C1 7.2.2 today, and the only conclusion I can come to at this point is that

1) Capture One has a tiling suppression algorithm, ie it does not only rely on calibration data and/or LCC, it also tries to suppress tile lines further after calibration data is applied (which probably is a good idea as calibration data cannot be 100% perfect)

2) This tiling suppression algorithm can in some situations go haywire and make things worse rather than better.

I was confused with a tile line that showed up in C1 but was invisible in RawTherapee. Programmer as I am, I modified the raw file by shifting the image data 500 pixels to the side and then reopened it in C1. You'd think that the tile line would move 500 pixels to the side right? Or perhaps stay in the same position where the actual sensor tile is. Neither of that happened, instead the tile line disappeared! This made me come to the conclusion above. That is when the image was shifted the tiling suppression algorithm got new image data to work with and succeeded that time.

I don't have the C1 source code of course so I cannot say for sure that I've described how it works correctly, but the current version surely has some issues with the tiling suppression.

 

[torger]

After further testing it seems like 1) this sometimes-failing tiling suppression algorithm is not run in tethered mode (ie then tiles go away), and 2) it's not run for P65+ but it is for IQ160, ie if I change tags so that C1 thinks the IQ160 file is a P65+ file the tiling issue goes away. Tested with 7.2.2.

So if you're an IQ160 owner and experiences tiling issues you can do a sanity check and see if the problem is still there in tethered mode. If it disappears then, it's not a problem with the back's calibration, but with C1.

I've done this investigation as a part of IIQ format compatibility testing in RawTherapee and Lumariver HDR (where I contribute to development), using C1 as reference... I've been pulling my hair why tiling has appeared in C1 when it was not there in the other programs. If someone is going to make a bug report to Phase One I can contribute with some technical details from my investigation, or just refer to this thread. A C1 developer which knows how the program is designed will realize in minutes what the problem is. It's a lot harder for me that can only see how the program reacts to changes I make to the raw files.

 

[Pemihan]

For everyone's information I got my IQ160 replaced. My dealer arranged for me to test a number of backs and pick the one I found best.
It is way better than the first unit, but still show tiling/lines when using my Cambo with Rodie 40HR, SK60XL and SK120 ASPH. However my prelimary findings is as torger writes that the tiling disappears when shooting tethered which also was what was happening with the issues I had with the Aptus-II 10 I had briefly but returned for this reason.
I will do some more testing shooting the same files tethered and to CF and see what it shows.
More later...

Peter

 

[Paul2660]

The whole thing about it going away when tethered, is odd. I can't see why C1 would use a different algorithm. However since I am now tethering as often as I can with the 260, I will try to check some of my files on a day when I shoot both ways.

Edit:

After more thought on this, I guess it could be due to the fact the the tethered images are loaded directly into C1 and non-tethered are on the card and don't have anything loaded until you import them into C1. However it has always been my understanding that no algorithms are run for tiling/center folding/edge rippling until you process the LCC in C1. When you tether, you still don't process the LCC as it's recorded in the Capture Folder.

Still an interesting issue.

Paul