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D1 "silent upgrade" mystery solved  
Monday, December 18, 2000 | by
As reported here last month, there is no so-called "silent upgrade" for the Nikon D1 that magically transforms its high ISO performance. But, some D1 cameras may require the replacement of a failing electronic part to rid images of a slight to noticeable diagonal pattern, especially in the green channel of images shot at ISO 1600 and above. Long time D1 owners should take special note of this, as a Nikon USA senior manager indicates that the handful of cameras repaired so far have been primarily those with early serial numbers.

The repair involves, at least in some cameras, the replacement of a part that affects the timing of certain internal processing steps. On the service order of California-based photographer Ron Reznick, the replaced part is described as an Oscillation Circuit (below).


Nikon USA service order indicating replaced Oscillation Circuit

An oscillator is a component found in many electronic devices. For example, an oscillator controls a computer's clock speed, or the speed at which its processor can chug through the instructions sent to it. A computer with an 800 mhz processor contains an oscillator that is pulsing at 800 million times per second. The D1 contains approximately 20 oscillators that must work in concert. If one fails, in most cases it must be replaced, since the timing of most or all of the camera's oscillators can't be adjusted.

Note: Within weeks of the December 2000 posting of this article, Nikon USA service departments were swamped with D1 cameras in need of an Oscillation Circuit replacement. One Nikon tech rep confided recently that he was concerned that some, perhaps many, photographers were not testing the camera in the way this article describes. Instead, cameras are apparently being sent in for the repair, regardless of whether the camera has been checked by the photog for diagonal pattern noise first. As this has apparently resulted in extended repair times for all D1 users in the USA (and probably other regions also), and possibly some cameras receiving a needless repair, please perform the noise tests outlined below before clogging up Nikon service with what could be a camera that is functioning properly.

Eric Hyman, best known as the author of the D1 RAW file processing application Bibble/MacBibble, sent his 5004XXX serial number D1 to Nikon's Torrance, CA service facility on December 1st. In addition to requesting that the dust on the CCD's cover glass be removed, Hyman asked that his camera be checked for excess noise. When he received the camera back on December 15th, the service order indicated than an "Other Electrical Part" had been replaced (below):


Nikon USA service order indicating replaced Other Electrical Part

While it's not clear whether the electrical part replaced was an oscillation circuit, an examination of Hyman's carefully-shot high-ISO, RAW format before and after repair photos reveal that the diagonal pattern was eliminated by Nikon's service work:


Portion of an ISO 1600 frame taken before Eric Hyman's camera was sent for repair


Portion of an ISO 1600 frame taken after Eric Hyman's camera was repaired

If you compare the dark green squares in each photo above, you'll get a good idea of what the diagonal pattern looks like. I discuss how these images were processed, and how to determine whether your camera is affected, later in this article.

The Nikon USA service order from a very early serial number D1 sent in by The Indianapolis Star stated that both the CCD itself, as well as an "Other Electrical Part," had been replaced before the camera was returned last week. Todd Moore, photo operations manager at the paper, indicates he had sent it in "for cleaning and for an autofocus check, and said I thought the banding was worse on it than on our other (newer) cameras."

Juergen Specht, fashion photographer and host of the D1 Discussion List, also had the CCD in his early serial number D1 replaced during recent servicing for excessive noise by Nikon in Japan. Before/after photos reveal that the telltale diagonal pattern was there before the repair, but is now gone. Specht has observed that in addition to the diagonal pattern noise disappearing, his camera now seems to produce much better-looking files overall. This to me suggests that his camera had more than just diagonal pattern noise, and perhaps is the reason the CCD was replaced.

Recently, the D1 I'd shot with since November 1999, serial number 5000752, was replaced by Nikon with a much newer body, serial number 5019121. While the swap was made because of a camera problem unrelated to diagonal pattern noise, I shot old camera/new camera pictures of the same scene that show a faint diagonal pattern in the green channel of 5000752 frames, and no such pattern in 5019121 frames.

My experience is similar to that of photographer Brian Caldwell, whose older D1 was recently replaced. Photos taken with Caldwell's original camera reveal a faint diagonal pattern in the green channel; the pattern is gone from photos taken with his replacement camera. Even though the exposure of Caldwell's original camera/replacement camera ISO 1600, RAW format photos is slightly different, and even though each was shot on a different WB setting, the result has been the same: a mild diagonal pattern evident in the green channel of the original camera test frame is gone from the green channel of the replacement camera test frame:


Green channel of Brian Caldwell's original camera showing diagonal pattern noise


Green channel of Brian Caldwell's replacement camera showing no diagonal pattern noise

Note: Don't base your decision to send in the camera for repair based exclusively on the serial number! While it does seem that mostly early serial number cameras are affected, I recently tested camera 5015731, and the diagonal pattern noise was as bad or worse in that D1 as any other camera I'd examined test frames from.


Nikon D1 serial number plate

The ONLY way to determine whether your camera is affected is to run the test outlined in this article.

Determining whether your camera is affected

It's clear, then, that some D1 cameras exhibit diagonal pattern noise and others don't. It's also clear that Nikon service is able to return affected cameras to factory spec by replacing one or more internal components, including perhaps the CCD itself in some cases. Therefore, it's important to be able to properly assess your own camera, to see whether it too requires professional attention.

The easiest way to determine whether your camera is afflicted with diagonal pattern noise is to shoot a picture of a 24 patch Macbeth ColorChecker or similar colourful object against a background with open shadow area. Eric Hyman's test frame was shot in his kitchen, and looks like this:


Eric Hyman's diagonal pattern noise test frame

The scene you shoot doesn't have to be fancier than this. It does, however, have to be properly exposed on the appropriate WB setting. And it really should contain dark neutrals and shades of deep green (one photographer reports using the greenish water of his fish tank as the test scene), which show off diagonal pattern noise the best. Use a tripod to eliminate camera shake.

Once you've selected a scene and adjusted the camera's exposure and WB settings, shoot a sequence of images at ISO 1600 on both JPEG Fine and RAW. You can shoot at other ISO settings if you like, but I suspect you'll find that the ISO 1600 frames are the easiest to judge.

The degree to which the pattern is visible is determined by several factors. Exposure and WB are among them, hence the reason it's important to lock those down during testing. Even more significant a factor is how the images are processed into finished files. RAW images processed through the latest versions of Nikon Capture (1.1.3 for Windows, 1.1.2 for Mac) will display the diagonal pattern if it's there, but just barely. Whether by accident or design, the latest versions of Capture seem to minimize its appearance:


Green channel of Eric Hyman's ISO 1600 test frame before the repair,
shot on RAW and processed through Nikon Capture 1.1.2 for Mac

The very same RAW file processed through Bibble 2.3 for Windows (I have not tried Bibble v2.4 as I write this), or MacBibble 1.2 for Mac, however, will prominently display the diagonal pattern if it exists (and won't if it doesn't):


Green channel of Eric Hyman's ISO 1600 test frame before the repair,
shot on RAW and processed through MacBibble 1.2 for Mac

JPEG Fine files will show off diagonal pattern noise somewhere in between Capture-processed and Bibble-processed RAW files. Therefore, I strongly recommend that Bibble or MacBibble be used in the search for the presence or absence of diagonal pattern noise in your own camera's images. The US$99 program is fully-functional for 10 days before payment is required, which should be plenty of time to process a handful of RAW files. If you haven't used the program before, you may find yourself registering it before the 10 days are up, as it delivers some of the best colour possible from D1 RAW format photos.

Bibble and MacBibble have a host of image processing options, more than can be explained here. If you configure the program's General Options window to match the screenshot below, however, and save out 8 bit TIFF files for viewing in Photoshop (or process the RAW files directly into Photoshop via Bibble/MacBibble's Photoshop plug-in), you will create finished files that will clearly show the diagonal pattern if it's there. Eric Hyman's before/after photos at the beginning of this article, for example, were processed through MacBibble.


MacBibble 1.2's General Options window (click for larger version)

Open up the finished file(s) into Photoshop, zoom each frame to 100% magnification, then view just the green channel. To do that, choose Show Channels from the Window menu, then click Green.


View the green channel at
100% magnification in Photoshop

Look carefully for diagonal (not horizontal or vertical) lines or stripes that aren't part of the scene content. If you see diagonal pattern noise, open up the JPEG Fine versions of the same scene and check that they contain the same pattern. Expect it to be less noticeable than in the RAW files processed through Bibble/MacBibble.

If you're struggling to determine if your camera is affected, you might also wish to shoot some ISO 800 and ISO 1600 photos on JPEG Fine, but with the camera set to B/W. With one camera I tested, serial number 5015731, the diagonal pattern noise was easy to spot in D1-generated black and whites shot at all IS0 settings, but especially ISO 800 and 1600.

Some may find it helpful to compare their own photos with those from Eric Hyman. I've processed his files into JPEGs using the settings shown in the MacBibble screen shot above, and posted them via the links below. The files, which have been saved at a quality level of 12 in Photoshop 5.5 to ensure that they are faithful to the uncompressed originals, are big. My apologies to modem users:

diagonal_bibble_before.jpg (3.2MB)

diagonal_bibble_after.jpg (2.9MB)

If you prefer, you may also download the original RAW files from which the JPEGs were generated:

diagonal_bibble_before.nef (3.9MB)

diagonal_bibble_after.nef (3.9MB)

To recap, the steps for creating and examining D1 photos for diagonal pattern noise are:

  1. Shoot a scene with dark greens and open shadows, ideally of a 24 patch Macbeth ColorChecker. Make sure the exposure is bang on, and the WB setting is appropriate for the illumination. Use a tripod, then shoot several JPEG Fine and RAW format photos. Try some B/W JPEG Fine frames also if you like.

  2. Process the RAW files through Bibble/MacBibble, using the settings shown above.

  3. Open the finished files into Photoshop, then examine the green channel at 100% magnification. Look for a diagonal pattern that is not part of the scene content. If you think you see one, open the JPEG Fine files and confirm you see it there too, only expect it will be less prominent.

What do I do if I see diagonal pattern noise?

If you're like most photographers, you'll want your D1 to deliver the image quality it was designed to deliver. If you do see diagonal pattern noise, you're going to have to part with your camera while Nikon performs any needed repairs. During the preparation of this article I spoke to staff at Nikon USA's Melville, NY and Torrance, CA service facilities, as well as Nikon Canada in Toronto, and can confirm that they are aware of the problem, know what to look for in photos from affected cameras, and are able to make repairs if they determine repairs are necessary.

I don't know whether service centres in other countries are up to speed on both identifying and fixing the problem, nor do I know whether it will be handled as a no-charge warranty repair (as it was for all the photographers cited in this article) in all countries. Nikon Europe's web site contains a list of service centres worldwide.

If you don't see diagonal pattern noise in your test photos, chances are your D1 is okay, and you can safely avoid boxing it up for repair. Keep in mind that this repair eliminates the diagonal pattern noise; the horizontal banding, as well as the white speckles that appear in high-ISO photos when they're sharpened for printing, will still be there after the repair, though they will likely seem less noticeable to you when compared to pre-repair images.

Once your camera is repaired, QImage Pro's noise reduction filter, or the Band Aide filter for Photoshop, will not be needed nearly as often. In fact, I use Quantum Mechanic Pro almost exclusively now to tackle D1 chrominance and luminance noise, calling on Band Aide only when the amount of horizontal banding left over is more than will be knocked down during the printing process. That is, once the layer of diagonal guck is permanently removed from the camera's images by Nikon's repair, the strategy for removing the remaining noise is very different than cameras affected by diagonal pattern noise. This is a good thing.

Thanks to all who contributed images and information for this article, including Eric Hyman, Brian Caldwell, Ron Reznick, Jeff Simpson, Todd Moore, Todd Brookes and Brice Eldridge Jones.

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