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IQ180 frustrations.

Wayne Fox

Workshop Member
I'll admit I've never really not been frustrated with my IQ180. My first one had color cast problems so severe it required an LCC even with the DF/28, 45, and 55 combinations, and also with the Alpa even with the 70mm Rodenstock. they swapped it, but still not great, and one reason I gave up on the technical camera is I really didn't want to shoot an LCC with pretty much every shot. I could get away with it using the 70mm and 120mm rodenstock, although most of the time with the 70 I felt it needed it.

I still frequently get issues that are frustrating, especially when I want to do some major adjustments. It seems now if I have to work over a sky pretty heavily, I"m in trouble, even C1 can't seem to map the 8 sensors correctly. I get all kinds of problems with what appears to be very subtle vertical magenta banding, and the middle seam will almost always show up. If I move into photoshop and work the file some more, it gets worse so I find myself doing things to "fix" it.

Will a recalibration help this? Is it too much to expect to get a perfect density/color match where the sensors are joined? Does anyone else fight some issues even with the DF and color casts?


this is a small crop from a sky output from C1 - this is the middle seam, not over towards an edge. I'm also fighting the magenta blotchiness that you can sort of see in this. A lot of my web jpegs show this in grey skies.
 
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Ztacir

Member
I think you are referring to the so called "tiling" issue which is inherent in all of the IQ backs which have 8 stitched smaller chips.
I have a very professional large format camera user and he has 2 IQ180s and he had to use them only for interior shots because both of the backs suffer heavily from tiling problem.In addition to this,he has been trying to solve the problem with Phase Company,the respond he got is his backs were calibrated well enough and all of the backs have tiling problem to such a degree,this should be condidered in acceptable levels.
Therefore,I think recalibration might help but not 100 percent.
Good luck,
 

vjbelle

Well-known member
Most importantly can you see this issue in a print of any kind? That's my bottom line and I print pretty large as I know you do. I have no issues with my 180 but have not looked at very pastel areas of an image at 100% or beyond.

As for the DF...... that's a whole other issue.

Victor
 

Jack

Sr. Administrator
Staff member
Wayne, when you say a small crop from output, do you mean this is actually visible in the processed TIFF? Or are you seeing it only in the 100% preview in C1? Next question is what ISO was that at -- I only ever see that sort or noise pattern at 100% view in relatively high ISO shots 400 or over normal, 1600 or over for S+.
 

Christopher

Active member
It probably is visible in print and in the TIFF file. Just my guess. My experience is that the IQ180 aren't as perfect as the P65 generation was.
 

vjbelle

Well-known member
Wayne,

I checked some of my 180 LCC files which are about as pastel as I can get. I opened up the files in either ACR or C1 and have looked for tile boundaries but can't find any even at 500% magnification.

If you like I can supply a raw file for your inspection.

Victor
 

Jack

Sr. Administrator
Staff member
It probably is visible in print and in the TIFF file. Just my guess. My experience is that the IQ180 aren't as perfect as the P65 generation was.
If it is, then IMHO he needs a new calibration file -- I have never seen anything like in my output files EXCEPT at S+ 3200, and even then, it absolutely did not show in a 4x enlarged print!
 

anGy

Member
Before purchasing my 180 I did test the demo one of my dealer. Same issue on some Cambo + 35mm Schneider shots (processed with LCC for technical cam). Not all the shots were problematic. But those with strong color cast were the most obvious.
I believed it was a specific problem of the demo system and ordered mine.
Before being delivered I saw that other users encounters that problem too and started to worry about that issue quite much.
Fortunately my current IQ180 seem totally exempt of that problem. Did not see it after 2000 shots taken with all kinds of lenses.
So saying that all IQ180 have that issue is untrue...
 

Christopher

Active member
My first back had it quite strongly, my second back still has it with difficult light. Now Phase has said, it is gone with the current firmware. I haven't had time to check it. You can see it with the old firmware in this shot. Left hand side. aboth the castle. It sill makes a stunning 1 by 2 meter print and normal people don't even notice it.

 

Craig Stocks

Well-known member
I've seen similar problems with my P65+, but only when I push the image saturation, and even then, only occasionally. When I have noticed it, the problem was not present in adjacent frames, so I wondered if it might be related to heat or lingering charges.
 

vjbelle

Well-known member
After extreme adjustment on my LCC file I was able to finally see the tile edges. This was after an extreme curve adjustment that I would never have attempted on any file that I have ever taken. Again I will supply you with raw files taken with my back for your inspection...... it may be helpful.

Victor
 

Wayne Fox

Workshop Member
Yes, I can see it in prints, as well as on the screen. It shows also when I downrez to web size, although I've done some repair work to minimize it on a couple of files. The magenta issues usually creates magenta/cyan artifacts when downsized to small web jpegs, something I've never seen until now. These were taken at ISO 35, exposure in the area in question is good, mid to lighter tone grey range. of course it doesn't show much until I try to make some contrast/density adjustments. It certainly isn't noticeable in the majority of my images.

Have sent a raw file off to Phase One to get their opinion. It seems every once in a while I get an image that something odd happens, here's one from last summer where lens flare cause this magenta cast. This isn't extreme flare, nothing is close to blown, but you can see the magenta color in the rocks. I'm sure it's a combination of the flare and the sensor, maybe unavoidable. I've seen this a few other times, once with my first IQ180 was just in some water at the bottom of an image (same general location) definitely no flare in involved in that shot.. This is the 28mm, 1.3 seconds ISO 35. (older firmware, 2.01 I think)
 

cunim

Well-known member
When I have gotten really analytical about my own IQ180, it has its little issues. Here is an LCC image after tech wide angle correction, transformed to gray, and with all sorts of manipulation to accentuate fine transitions. I also show a measured profile taken from an unmanipulated image.

If we think of the camera as outputting gray levels from 0-100% of an arbitrary scale, the center seam is less than 0.2%. That's not too bad, though visible if you make a serious effort to show it.

In contrast, look at the patches at the top and bottom of this (vertical orientation) CCD. They are much worse. A profile from this area (shown in the yellow box and graph) shows a dip of >0.5%. Has it bothered me in real-life images? No, but there is no specification for this type of thing and I wonder what it is. Showed this to Phase, who asked to get the camera for a look. They sent it back in much the same state so I don't think it bothers them much. Me neither, but I'd like to understand what is going on. The color patches Wayne sees are interesting, and I will look for them on mine.

Peter
 
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Christopher

Active member
Don't get me wrong, I am very happy with my IQ180 and don't have much to complain, but I get that some people aren't to happy that a product that costs something around 30-40k shows any such faults even in more extreme editions. I just have to look at my 5D or Nikon, which I can push around at ISO 1600 without ANY such effects.

However, I think this is just what MFDB are about. They aren't perfect, but as long as it works they are just amazing.


NOW I just whish it would be possible, or should I say easy to map all this HUGE DR into one image in C1, this sadly isn't possible. Or not to the extend I would like. Note to Phase, take a look at Adobe, they !currently! do a better job when it comes to DR.
 

dougpeterson

Workshop Member
There is a specification for this. It's pretty simple. If it's meaningfully visible in normal photographic work with recommended lenses and current (3.0.1) firmware then it's not in spec. If it only shows up in a meaningful way when you apply crazy amounts of adjustment to the file then it's not in spec.

Normal photographic work includes pretty strong adjustments (that's the whole point of a DB, they hold up under strong styling and adjustment). I do not mean "I'll adjust it until I see it" kinds of adjustment; the reason being ALL cameras will show terrible things if you look hard enough. For instance: take a 5D mark 2 file, shoot an LCC at low ISO, apply the LCC to itself (to even out any variation in color and brightness) and then auto-adjust the exposure (effectively stretching the histogram way out). You'll see some really awful things. Then breath, reset the adjustments and try to look for those issues in a normal file with normal adjustments - you won't see them.

@Angy: the Schneider 35XL is not a "recommended lens" with the IQ180 (as you know). Especially with movements you may notice artifacts of this issue. The 35XL can still produce great images (including yours!), but such issues are possible with that lens. A Rodenstock 32HR or 40HR are better alternatives regarding interaction with the IQ180 sensor.

@Christopher: Lightroom 4 is out and does great with harsh DR (as you note) but I think you'll be very pleased with C1 version 7 when it comes out :). VERY pleased.
 

cunim

Well-known member
There is a specification for this. It's pretty simple. If it's meaningfully visible in normal photographic work with recommended lenses and current (3.0.1) firmware then it's not in spec. If it only shows up in a meaningful way when you apply crazy amounts of adjustment to the file then it's not in spec.
Doug, I would agree that if CCD defects are not visible in normal use, they don't matter. In fact, the things I am sensitive to tend to vanish when there is anything other than a uniform field of view and, as you say, all consumer cameras have flaws. End result, I'm happy with the IQ. It is good enough, even if the system does lose its custom settings.

However, this topic relates to frustration from some who are concerned because of subtle defects in their expensive cameras. In that context, I take issue with the word "meaningful". To the sensitive amongst us, these defects are meaningful. Who decides? In the end, it is the individual user who must decide and Phase must help him or her to do that during the product selection process.

That is where Phase and its dealers should be aggressive in tracking and collating reports of seams, blotches, etc. You already do it for color casts, for example. I hope that reports from an expanding user base will help you guide those users in what to expect from their equipment.
 

rupho

New member
@Christopher: Lightroom 4 is out and does great with harsh DR (as you note) but I think you'll be very pleased with C1 version 7 when it comes out :). VERY pleased.
C1 version7? Have you seen it already Doug???
Curious to hear more about it!
I am waiting desperately for LCC batch processing among other features.
 

johnnygoesdigital

New member
There is a specification for this. It's pretty simple. If it's meaningfully visible in normal photographic work with recommended lenses and current (3.0.1) firmware then it's not in spec. If it only shows up in a meaningful way when you apply crazy amounts of adjustment to the file then it's not in spec.

For instance: take a 5D mark 2 file, shoot an LCC at low ISO, apply the LCC to itself (to even out any variation in color and brightness) and then auto-adjust the exposure (effectively stretching the histogram way out). You'll see some really awful things. Then breath, reset the adjustments and try to look for those issues in a normal file with normal adjustments - you won't see them.
The major difference is obviously price, so I'm pretty sure the 5D owner is going to be less annoyed than the IQ180 owner. Also, chances are the IQ180, owner is going to print big, where artifacts may not be removed at the pixel level.
 
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