Category Archives: Technique

HP DesignJet annual checkup

Printing

A little goes a long way.

My HP DesignJet 90, the 18″ carriage model, was commissioned March 14, 2006, so it’s approaching seven years in age. One recent print with a dark black silhouette showed less than perfect blacks and deep, lustrous blacks are one of the many strengths of this excellent printer. Amazingly, B&H still lists the 24″ DJ130 for under $1300 new, and all ink cartridges and printheads remain available on their site, though you may have to hunt about a bit for the special swellable paper which absorbs the ink dyes used by the machine. Regular modern pigment ink papers do not work.

The HP DJ30/90/130 series is blessed with truly outstanding diagnostics and a quick checkout was all it took to find the cause.

First, I dialed up the HP Maintenance Utility which uses online software at HP. For Mac users you have to use OS Snow Leopard or earlier or an even older PPC machine, as HP never updated the software to run on Intel machines. Snow Leopard comes with Rosetta, the PPC emulator software and will run the HP Maintenance Utility fine. Apple recently re-released Snow Leopard on DVD and if you want to run the HP Maintenance Utility on a modern Mac it’s your best choice, though whether it’s even installable on the latest Macs I rather doubt.

I use a decade old iMac which runs Tiger and uses a PPC CPU. Unlike its modern day descendants it does not overheat and refuses to die.

You can run all these print jobs using plain paper in your printer – 8.5″ x 11″. Here’s the Image Quality Diagnostic – this one can unfortunately be run only by using the online software and is the best for determining if a printhead is failing:

No real issues are disclosed here but printhead alignment is called for, judging my some of the colored squares in the center section. The full interpretive section for the above appears here.

Then I ran a printhead alignment which can either be done using the online utility or using the button presses illustrated here:

This did disclose a problem with the black printhead:

The large ‘X’ mark above testifies to a worn or blocked head.

Before deciding on cleaning or replacement of the head I ran the ‘Information Pages’ printout (see above) and got this:

Gaack! The black printhead is 2,534 days old, meaning 6.9 years. It’s the one which came with the printer when I bought it new in 2006! So rather than trying to clean it, I simply replaced it. Pigs get slaughtered.

After replacement of the black printhead – the new one has been on my shelf for ages and is already out of warranty! Some users claim that heads over 30 months old will not work but obviously my experience does not bear this out.

When a printhead is replaced in these machines, they automatically run a printhead alignment which takes some 10 minutes and requires one sheet of plain paper.

Here’s what I got:

All is well.

Finally, out of curiosity, I ran the ‘Paper Usage’ report:

Some advice on older DesignJet printers:

Would I buy one of these used? Only if I could see the Usage Reports and Diagnostics shown above. Many were used by printshops which have beaten the heck out of them. New heads – there are six – run $35 each and cartridges cost a similar amount, so all new heads and supplies total $420. Add $35 for feed tubes. No bargain. Further, if the printer has been unplugged for any period of time, reckon on changing the clogged feed tubes as I had to do when mine went into storage for a few months when I moved a few years back. I explain how to do that here.

Bottom line? I would not pay more than $200-400 for a lightly used HP DJ90/130 (18″/24″) printer, anticipating that some parts will have to be replaced.

Spare parts:

I get mine from Spare Parts Warehouse. The ink feed tube assembly runs $35 and is easy to replace.

Would I buy a new HP printer? Hell NO. I would not buy anything from America’s worst run business whose customer service is a joke. Buy an Epson. The 24″ model runs $3,000 but they will fix it for you when it breaks.

Result:

Success. Perfect blacks were restored.

Here’s the print which was giving me problems:

In the extract, below, you can see a tear sheet of the old print, before the repair, superimposed on the new – night and day:

Printhead failure and analysis:

I have illustrated this before but it bears repeating. Right after the annual checkup, above, the DJ started printing everything with a green cast. This indicates printhead failure as ink levels were fine.

Here is the analysis chart:

I ran the diagnostic report using the online HP utility and this is what I got:



Diagnostic report showing printhead failure.

Comparing with the above chart, you can see that the color patches at A1 (should be magenta), A2 (should be purple) and B2 (should be red) are faulty.

The chart states that A1=M, A2-C+M and B2=Y+M. Note also that the central patch in the left middle section is wrong – it should be magenta. M (magenta) is the common factor to all four error conditions, so I concluded that the Magenta printhead was faulty. $35 to B&H later and it was replaced (a 30 second task) – do insert plain paper when doing this as a printhead alignment chart will be automatically printed when a head is replaced, and the printhead alignment will be performed automatically. It takes some 10 minutes, so be patient. Sure enough, re-running the diagnostic report showed all is well and the DesignJet is back to perfect operating condition.

Pixel peeping fallacies

Lightroom, Nikon bodies, Technique

Know what you are looking at.

When I migrated from the 12mp Nikon D700 to the 24mp D3x, I did a bunch of thinking about the justification for more pixels.

If you do not propose increasing your print size or cropping more severely, more pixels will likely not serve you well. I contemplate making both larger prints and cropping more when needed. Thus, the higher pixel count sensor makes sense for my contemplated needs.

When I first uploaded D3x images from the D3x to Lightroom, I naturally previewed images at 1:1 and remember thinking “What’s the big deal? This does not look any better than the files from my D700 at 1:1.”

The problem, of course, is that I was not comparing like with like.

Here’s a simple table to illustrate the issue.

I have compiled data for four common Nikon sensors – the math is brand-independent, it’s just that I know these bodies and have RAW images from all. I enlarged these original images using the 1:1 preview function in LR4 and measured the image width on my 21″ Dell 2209WA (1650 x 1080) display. So in the table above, using the D2x as an example, the 12.2MP sensor delivers an image which, if printed 1:1, would be 47″ wide.

What does Adobe’s Lightroom mean by 1:1? It means that images displayed 1:1 are displayed at 90 pixels/inch – you can confirm this by dividing the ‘Sensor – W’, the pixel count across the width of the sensor, by the ‘Width at 1:1 in inches’ and in each case you will get 90 dots per inch. That’s good for an LCD display or for prints looked at from a reasonable distance. If you want to stick your nose in the print, then you want to limit the pixel density to 240 pixels/inch, which is the same as dividing the above ‘Width at 1:1 in inches’ data by 2.7. So a 240 pixels/inch print from the D800’s sensor, for example, would be 31″ wide (83/2.7). But in practice, you do not need that high a density in huge prints.

As you can see, comparing a D700 image with, say, a D800 image, is not fair if identical 1:1 preview ratios are used. You are comparing a 46″ wide image with one almost twice as large at 83″. To make the sensor comparison fair, you need to preview the D800 image not at 1:1 but at 1:2. That will yield approximately the same reproduced image size, making for an objective comparison of resolution and noise if the same lens and technique are used for both.


Preview options in Lightroom.

Yet, I suspect, many snappers fall afoul of these erroneous 1:1 comparisons concluding:

  • I need better lenses with the newer body
  • My images are blurred, I need to use faster shutter speeds
  • My focus is out, there’s something wrong with the camera

All of the above lead to much time and money wasted in fixing the unfixable. Bad data.

It is indeed quite likely that your new sensor out-resolves the limits of your older lenses at 1:1. It’s also reasonable to expect motion blur to be more visible at the same shutter speeds if you use faulty comparisons. And the chances are it’s your technique not your hardware which accounts for poor focusing, the errors only becoming visible at double your former preview magnifications. But, unless you contemplate making crops to one quarter of the area of your previous sensors or making prints 7 feet wide instead of 4 feet wide, your sensor upgrade is only causing you needless pain.

My first conclusion with the D3x compared to its D700 predecessor was all of the above, until I figured out what I was looking at. Some comparisons are easily drawn. It’s clear for example, that the D700 has lower noise than the D2x for the same image size, hardly surprising as we are comparing a recent FF sensor with an older APS-C (D2x) one. The total pixels and 1:1 print sizes are almost identical. On the other hand, comparing the D700 at 1:1 with the D800 at 1:2, for like print sizes, shows little difference. It’s only when you double preview sizes with the D700 to 2:1 and the D800 to 1:1 that you see the greatly superior resolving power of the D800, as the number of pixels you are looking at in such a comparison is tripled in the case of the newer sensor.

Nikon has not helped the situation. After their affordable high pixel count FF bodies – the D600 and D800 – came to market, they started publishing pieces intimating that only their very costliest and newest lenses were ‘good enough’ to extract the best from the new sensors. The rest of the sheep writing purportedly critical analysis followed right along. It’s called sales and makes little sense. Some of Nikon’s highest resolving power lenses were made ages ago, long before digital sensors existed – any Micro-Nikkor macro lens pretty much qualifies (55, 105 and 200mm) – as do a host of pre-Ai lenses, many over four decades old. If you like the latest and greatest (and costliest) have at it. But don’t believe everything you read from such conflicted sources. Their primary focus is not on your image making capabilities but on your wallet, be it through sales (Nikon) or click-throughs (the whores who parrot this stuff as if it was technically proved fact).

So before you chuck out your old lenses and start buying costly superspeed exotics which allow the use of faster shutter speeds, while contemplating return of the body to Nikon for repair of focusing errors, ask yourself what you are really looking at when you preview those enlarged images on your display.

Practical implications: It’s not like you can avoid buying new gear with lots of megapixels by trying to save money on something with fewer. Everything has lots of pixels today. 12MP is hard to find at the lower limit. But the practical implication of this rapid technological advance is that, for those on a budget, substantial savings can result from buying the previous generation of hardware, comfortable in the knowledge that while 8-12MP may not be a lot, it’s more than enough for 99% of needs. DSLR bodies like the Canon 5D, Canon 5D MkII, Nikon D700, Nikon D2x, Nikon D3 and others no less capable from Pentax and Sony offer tremendous savings just because they have been replaced with something that measures better in a comparison table. Heck, a lightly used 6mp Nikon D1x can be had for under $250 and will offer tremendous capability, outfitted with a $50 mint MF Nikkor, far in excess of the abilities of most. The barrier to entry to good hardware has never been lower. 16″ x 20″ prints? No problem. Why do I say that? The D1x’s sensor is 3,008 pixels wide, so for a 90 pixel/inch print (what Lightroom shows at 1:1 preview) you would get a print sized 33″ x 22″. Unless you stick your nose in it, it will show just fine.


Nikon D1x. Add Nikkor of choice.

AeriCam

Technique

A fascinating device.

Waiting at the traffic lights in San Francisco the other day, my eye was caught by this plaque so I quickly made a snap.

It turns out that AeriCam manufactures a state-of-the-art miniature helicopter which permits a movie camera or DSLR to be attached for aerial photography. It costs $12,000 ready to fly. They also manufacture a gimbal mount for an additional $2-3,000 which helps minimize vibration and the results are quite extraordinary in their smoothness and professional quality.

Results from their six bladed ‘hexacopter’ can be seen by clicking the image below.


San Francisco from the Bay Bridge. Click the image for the video.

If you can overlook the extraordinary car skills displayed by the driver, focus on the smoothness of the aerial shots. It’s not quite clear to me how one gets a video feed from the camera to the operator to permit accurate composition, but at $15,000 this device appears to be far cheaper than helicopter rental, and is available in moments to any cinematographer. The rather sparse web site refers to a ‘video transmitter’ so I assume that beams a live picture back to earth to the included ‘9″ SonyMonitor’. Bad weather? Put it back in the box and come back another day.

The recommended payload is 10lbs which will easily accommodate a big DSLR and lens. The device is GPS capable so programming locations should be easy. Order lead time is 6-8 weeks. American ingenuity at its best.

Snapseed for OS X improved

Photographs, Technique

Welcome enhancements.

Snapseed is a simple and effective application for both iOS and OSX for conferring special effects on pictures. I mostly use it to add grunge in those snaps which merit the treatment.

Now the two major issues I had with the OS X version of the application have been fixed by Nik Software. First, you can export to Snapseed directly from Lightroom and second the application will now accept TIFF files rather than just JPGs. I have tested both and can confirm the revised version does both perfectly, and when you save the file it’s stacked with the original in Lightroom.

Here’s a snap processed in Snapseed with grunge, vintage effect and frame added:

On Broadway, SF. D700, 105mm f/2.5 Nikkor-P at f/11.

Snapseed for OS X

Photographs, Technique

A great effects app comes to the desktop.

I wrote about the use of the iOS app Snapseed here and have had lots of fun with it since on my iPhone 4S. Nik Software has now released a like-featured OS X version, althjough it’s four times the price of the iOS version at $20. Go figure.

Snapseed in the Mac AppStore.

It’s 57mB (twice the size shown above) and downloads in a couple of minutes. As I catalog all my snaps in Lightroom, I went to LR3->Preferences->External Editing and added Snapseed as an export option. Thereafter it’s a simple matter to export a RAW original to a JPG in Snapseed – Snapseed does not support TIFF or PSD files, so exports to it are converted to JPG. Likewise, it can save in JPG only, albeit respecting the full size of the original – meaning 3056 x 4576 for a RAW file from my Panasonic G3.

The timing of the app’s release could hardly have been better as I had just snapped a worker at the Transbay Terminal construction site on Howard Street in San Francisco with a backdrop of massive I-beams and the original needed a little something to confer the industrial feel I wanted. An export to Snapseed saw the original thus:

Original exported into Snapseed.

A few quick tweaks in the ‘Grunge’ panel were followed by a touch of CenterFocus/Vignette/Blur, and with the addition of a Grunge Frame I had what I wanted. Saving the file seemed to place it in the Lightroom directory, judging by the filename, but I could not see it in the Lightroom Grid view, so decided to save it to the Desktop and import it thence to LR3. I suspect I’m doing something wrong and will look into it – with PS CS5, for example, a ‘Save’ places the file right next to the original in the LR3 Grid display.

Here’s the result:

At the Transbay Terminal site, SF. G3, 45-200mm @ 78mm.

The simple user interface, the quality of the many effects and the general speed and ease of use make this a bargain, even at $20, compared to $5 for the iOS version. Sure, you could do all of this in iOS, laboriously exporting and reimporting the picture, but life’s too short for that. This is no substitute for the industrial strength of Photoshop, but try doing all of the above in under one minute in that behemoth of an application. Snapseed is proof that a few carefully selected effects in a well engineered product suffice most of the time.

Here’s another before/after of an image also snapped yesterday.

The original:

The shoe. G3, kit lens @35mm.

After:

After Snapseed.

In this example I used the ‘Tune Image’, ‘Drama’ and ‘Frames’ settings. ‘Tune Image’ includes selective options, though I did not use those here. Snapseed has done a great job of enhancing drama and bringing up detail in the bricks, highlighted by the setting sun.

Update March, 2013:

Sadly Google, which acquired Snapseed along with Nik Software, has discontinued the OS X version. Quite why not keep it available, when the support and development costs are zero, beats me but doubtless Google is Doing Evil, consonant with its missing moral compass:


Recent App Store search for Snapssed for OS X.