Why ColorBase?

October 4, 2012 by

After my recent post about the new ColorBase version, a friend asked the question: “why is it better than factory calibration?” I though this could be interesting to other people, so here’s my (longish) answer.

Some background first. In the grand scheme of things, building a color profile for a device is a two-step process. The first step is calibration, which sets the basic operating parameters of the device to a well known (sometimes standardized) default. In case of monitors, calibration sets the black level, white luminance, color temperature and tone reproduction curve. In case of printers, it sets the relationship between color values and the actual amount of ink laid down to be linear – this is why this step is called linearization. The second step is the actual profiling. Here the software determines the color reproduction characteristics of the device and creates the profile.

On the low end, manufacturers tend to skip the calibration step, doing only the profiling. This is a nasty trick and the reason why I think that cheap colorimeter packages that can’t do the calibration step are downright dangerous and actually worth nothing. On the high end profile making is always preceded by calibration.

Speaking of printers: the lack of calibration (linearization) is less noticeable here, because profiling packages do a linearization step under the hood before starting to build the profile. This is not that accurate as the separate step, however (“true” linearization controls parameters in the rasterization process, whereas “simulated” plays with the color values). So basically it is more or less done for printer profiles.

My favorite example for showing color reproduction differences across devices is the TV department of your favorite electronics store. Almost every single one displays the same content differently. Consumer printers are the same. Take two Epson 2880s, and they will print different colors. In case of professional Epsons, all the devices are “factory calibrated” to be as identical as possible when they leave the factory. But this does not mean that they will not drift over time! And because of this drift (and inherent difference in consumer models) you’ll have to re-create all the profiles from time to time. Which could be a daunting task.

To be able to decide whether your device drifted out of tolerances, high end profiling packages provide a validation tool that measures the color reproduction accuracy of the calibrated/profiled device. This way you can check the status periodically and recalibrate/re-profile as needed – instead of doing this blindly every month or so.

Epson’s ColorBase is a software for both linearizing the printer driver and a validation tool for checking the linearization accuracy. A welcome extra is that it can do this for higher-end consumer printers. So one can utilize ColorBase in two different ways:

  • Use it to measure accuracy, and redo the complete linearization/profiling for each of the papers when the accuracy has drifted. This could still be daunting for several papers, but this provides the utmost precision.
  • Use it to measure accuracy, but only redo the linearization if the printer became out-of-spec. Because ColorBase returns the printer to the state it had been before creating the profiles, there are pretty good chances that the profiles will remain accurate.

I have been using the second method for five years with great success. And the longest period that the printer was in-spec reached 2 years with my late 4800. This demonstrates that we are talking more about peace of mind and process control here than visible results. This stuff is about to catch when something goes wrong before it ruins several prints.

And what’s the difference between factory calibration and ColorBase? Actually they are two different things. Factory calibration is for making sure that pro printers are identical when they leave the assembly line, whereas ColorBase is a tool for employing process control.

I must mention two glaring omissions in the package, however. Ink limiting and support for third party papers. You can control ink within the printer driver to some extent, but this should be done with the linearization step. Over-inking could be a serious problem using the driver with some papers. Not supporting third party papers could be worked around by linearizing the printer to the Epson paper selected as the media type for the third party paper (for example Velvet Fine Art in case of Hahnemühle Photo Rag). You will not have a linearization for Photo Rag (which would be the desirable), but at least you’ll be able to build its profile on a solid and consistent base.

If you need ink limiting and linearization for custom papers then moving to a RIP is the only solution these days.

Filed Under: Color Management, Printing Tagged With: , , ,

Calibrating the Retina Display

August 22, 2012 by

In a recent post about the new MacBook Pro I mentioned that it “calibrates very accurately”. Let me elaborate more on this subject.

My standard display calibration parameters are: 80 cd/m2 luminance, D50 white point and L* tone reproduction curve (TRC). I had used this setup for years with my EIZO on both Windows and Mac computers. I’m also using a complete L* workflow (with ProStarRGB working space in Photoshop for example). So my target was the same for the Retina display.

Due to the incompatibility with OS X 10.8, I gave a shot recently to basICColor display for color calibration. The MacBook Pro arrived just before the trial expired on my old desktop and I got another 14-day trial license for the new machine. This allowed me to test the software again before committing to the purchase.

So I spent the whole Sunday on profiling displays and evaluating them side by side. My initial thought was that it’ll be a piece of cake. How naive was I…

First, I calibrated both monitors to the aforementioned conditions and profiled them. The EIZO was good as usual, but my usual 50% gray desktop background on the Retina display showed a strong, ugly reddish color cast. Black levels were also quite different, making it hard to see and make decisions about contrast and work with delicate shadows. I was far from being satisfied with the results.

Then gave a try to X-Rite’s new i1Profiler. Although printer and press profiles created with the application literally sing, there’s a lot to be desired regarding its display calibration abilities. Frankly, I still prefer display profiles from the old i1Match application (not available since Apple eliminated PowerPC emulation from OS X). It also lacks L* TRC support, the most perceptually uniform TRC you can get is the one modeled after the sRGB color space’s TRC. The results were disappointing. Even watching a movie I complained about burnt highlights and ugly gradations (causing a little bit of indignation from my Loved One).

I was thinking what the hell should I do to make the otherwise gorgeous display usable. And a faint memory reared its head. Some 8-9 years ago I evaluated a display calibration and profiling tool named ColorEyes Display Pro. Downloaded the latest version and gave it a try. This was the first time I got acceptable results without the unbearable reddish cast.

The app works fine under 10.8. There’s one thing to watch for, however. For better monitor match it recommends to calibrate to “absolute black” instead of treating the monitor’s lowest black as 0/0/0 pixel value. Yes, this will cut the visibility of the deepest shadows on the monitor. Actually it behaves just like paper and ink, so it’s even easier to fine tune my images for printing (and of course I can always use the levels tool to bring up the shadows a bit temporarily). This worked out very well. Examining my favorite test image side by side showed only very small differences. Actually, I think the Retina display is usable for semi-critical color work, such as quick edits during field trips.

Unfortunately, the desktop and every non-color managed app still had a slight reddish cast. After 4-5 hours of trying every imaginable solution (tuning white points, changing colors, etc, etc.) I ended up with two profiles. One, the usual 80cd/D50/L* for editing images and another one with 80cd/5300K/L* for other types of work I do (such as app development and writing). With 5300K the non-color managed apps look just like D50 does on the EIZO, and even I do light photo editing with it sometimes.

The two displays side by side now look as if they were prints on a matte Hahnemühle Museum Etching and a semigloss Hahnemühle Photo Rag Baryta. Sweet!

Some closing numbers. With absolute black level calibration I can easily see into the shadows as low as about level 8 (from 255) on the EIZO and as low as about 6-7 on the Retina. Maximum deltaE is 0.90 for the EIZO with an average of 0.5. Maximum deltaE is 0.63 for the Retina display with an average of 0.34. Most impressive! And the Retina display’s color space covers roughly the entire sRGB space (as viewed in ColorSync Utility).

I must mention again that the resolution advantage is huge! Just enabled Retina support this morning in the application I’m working on these days and it looks really awesome. The EIZO doesn’t get much love these days…

Filed Under: Color Management, Computer Hardware Tagged With: , ,

MacBook Pro with Retina Display

August 18, 2012 by

It took a month, but my machine finally arrived two days ago. I spent the whole yesterday on moving my digital life over to the new machine and set it up for work. This post is a collection of my initial impressions. I will not reiterate the specs that can be found in numerous online reviews. All of those I recommend watching just this one.

My configuration is the 2.6GHz machine with 16GB of RAM and a 500GB SSD.

Winner of Two Lotteries

You enter two “lotteries” when you buy an Apple notebook. The SSD lottery and the display lottery. The reason is that Apple sources these components from two vendors: Samsung and Toshiba for SSDs/flash memory (I will use the Solid State Disk term instead of Apple’s “flash memory” marketing talk from now on – because these are all SATA connected SSDs – although in different form factors) and Samsung and LG in case of displays. Unfortunately the non-Samsung options are vastly inferior to the Samsung ones.

For example, Samsung SSDs are using the great Samsung PM830 controller. The Toshiba one use a Sandforce SSD controller. Sandforce SSD controllers compress all the data before it gets written into the chips for an almost twofold throughput increase. But if you are like me, and use FileVault to encrypt your disk then this compression becomes useless: almost random data can’t be compressed. Which results in halved performance. Fortunately, for larger capacity drives Apple seems to be using the Samsung ones. So I ended up with an 500GB Samsung SSD. One win.

You might wonder why did I mention 500GB instead of the advertised 512GB. Because the 512GB is simply a lie. The drive actually measures 500GB (if you count 1,000,000 bytes as one GB – as the storage industry as well as Apple does) and 476GB if you count (1,048,576 bytes as one GB – which is how many bytes a GB truly is).

Regarding the display lottery, lots of LG manufactured panels are defective out of the box. Just execute the command in the linked article to show your display’s manufacturer. LP is for LG and LSN stands for Samsung. I have a Samsung panel. Another win.

Is the Lack of Upgradeability a True Problem?

Lots of people on the Internet fret about this. Frankly, in the last 15 years I can only mention two occasions when I upgraded memory in my machines. And CPUs were never changed. Disks are another story. Before SSDs I regularly went to faster disks as they became available. But since I’m using SSDs I don’t feel the need to upgrade yearly. I usually buy my machines maxed out with RAM and disk, and opt for the one-less-that-the-fastest CPU option (they cost way less and the performance difference is negligible). So the lack of upgradeability is not a problem for me.

And on the positive side, soldering RAM to the motherboard gives some huge performance benefits (read the section below the graph). Wow, 99.9% processor bandwidth utilization IS something!

Two Missing Pro Features

ECC memory and 30-bit display output capability. I know that ECC (Error Check and Correction) has disappeared from consumer machines and Intel only supports ECC with their Xeon processor line, but 16GB is a lot and for mission critical work (like huge CAD models) ECC is a must. So for situations where it is not acceptable that your memory can forget a few bits here and there, the Mac Pro is the way to go. For example I use a Xeon E3-based server machine with 16GB of ECC memory.

The other one is 30-bit color. This is available on all current high end graphics displays and NVIDIA makes mobile chips that support 30-bit. Usually these chips are completely identical to the consumers ones Apple is using, just high precision stuff is enabled in them (I remember those times when I hacked consumer NVIDIA cards to Quadro ones…). For a notebook at this price point, pro graphics should be the standard.

Needs a Thunberbolt Dock

On the left side of the machine I have:

  • The power cable.
  • A mini displayport to DVI adapter for my EIZO CG241W display.
  • A Thunderbolt to Gigabit Ethernet adapter.
  • An USB connection to the EIZO. Keyboard and mouse is attached to the EIZO’s hub.

Looks ugly. And plugging in all these when I use the machine as a desktop is a hassle. I can hardly wait for Matrox’s solution.

Usability

The machine is light (for such a powerhouse), fits neatly into the notebook pocket of my Lowepro Pro Trekker 400. Key travel is a bit short, but it’s not really a problem. I miss PageUp/PageDown and Home/End keys…

It gets a bit warm during use, but it’s bearable. As the majority of current applications are incapable of driving the four processor cores (with eight processing threads), so fans are spinning silently. Even if you can put some heavy load on the machine they produce an almost pleasant noise. Nothing disturbing (and believe me I’m overly sensitive to machine vibration and noise).

Battery life is rather short – I found it about 5 hours in my normal usage patters. This is way less than Apple’s advertised 7 hours, but there are reports that Mountain Lion causes this reduction. We’ll see.

Applications and the Retina Screen

The screen resolution is astonishing. Brightness uniformity is not on the same level as my EIZO (actually I would score this as pretty bad). The display calibrates very accurately (in one spot at least). I was surprised that it produced less deltaE2000 than the EIZO. If uniformity would be better, this could be a great graphics display. All in all I want this high resolution on my desktop graphics monitor! Hope that either EIZO or NEC will come out with a high resolution display like this.

I would also note that the Intel integrated graphics is not capable of handling such large amount of pixels. You can’t even watch a movie full screen using integrated graphics, so the machine uses the NVIDIA chip a lot.

The real problem is that most of the applications are not yet ready for supporting the HiDPI modes of the Retina display. These apps would really need the upgrade:

  • Photoshop
  • Lightroom (it displays UI text in high res, but everything else is pixel-doubled)
  • Capture One
  • Kindle

Others, like Parallels Dekstop and VLC, already support the display. It’s still a waiting game. And the display would only realize its full potential when these apps become ready.

Filed Under: Computer Hardware Tagged With: , , ,

Kirk L-Plate for the 5D Mark III

August 10, 2012 by

Got my Kirk BL-5DIII plate on Tuesday, and would like to share some thoughts about it. It’s a good design with some oversights.

Pros:

  • You can buy it right now. The RRS plate for the 5D3 is still backordered. Shipping to Hungary was also $27 less with this plate than it would be for the RRS. Both plates cost $140.
  • I really appreciate the second locking point at the strap loop. My 1D2 fell off from its RRS plate a few years back. The plate was on the 1D2 for a few years, and the thread in the tripod screw socket suddenly gave up. Fortunately the losses were just a remote switch and the EUR 70-80 repair cost of the socket. All in all, having a second mounting point could prevent this. This is a big plus.
  • It is light. Feels lighter than RRS plates.
  • I prefer its form factor compared to the RRS plate.

Cons:

  • The base of the plate around the screw does not fit flush against the camera body. There’s no precise locking point when you tighten the screw. I suspect that I could tear out the socket if I over-tighten. I definitely prefer RRS and Wimberley plates in this regard.
  • The front of the plate tends to punch a hole in your hand if you happen to handhold your camera. It is a major oversight! It was a painful discovery on my part, so I immediately reached for a file and rounded the offending corner. But this should be done by Kirk!

“Custom” Rounded Corner

Overall I’m satisfied with the plate, and would give it 3.5/5 stars.

Filed Under: Photo Equipment Tagged With: , , ,

Gitzo 3532LS First Impressions

July 20, 2012 by

I had sold my 8 years old Gitzo 1325 tripod along with my 5D Mark II a few weeks ago, so I was looking for a new tripod. There was nothing wrong with the 1325, I just had an opportunity to step up. I was looking for something similarly spec’d. This boiled down to two choices: the new (2012) Gitzo 3532LS and the RRS TVC-33. They are shockingly similar in all aspects, except two: the “I’m an expensive tripod, steal me” pattern on the RRS and their prices. The RRS retails for $925 (which is about 960 EUR after shipping and import duties), but I bought the Gitzo for 680 EUR including shipping (both are net prices). That is, the RRS is 40% more. Simply does not worth it.

The 3532LS is a great tripod. But even the 1325 was a great one. Weight is about the same. Length is about the same (add or take a few grams and millimeters). Gitzo added some nice features to their newest generation, however:

  • Leg locks. On the 1325 I had to learn the exact torque that I should use to tighten the locks – tightening the upper ones a tad more than the lower ones. Just to avoid inadvertent unlocking. The G-Lock system does not let the legs to rotate, so this is not an issue any more.
  • Included spiked feet and snow feet. The spikes are rubber covered. The snow/mud feet looks a bit clumsy compared to the huge one I had for the 1325. But that size was really prohibitive – I had used them only once in 8 years. These smaller ones will find a permanent place in my bag.
  • Spare washers and grease is included (as well as wrenches and a dust cover).
  • Although I had no issue with the 1325’s top plate locking system (and I had carried it over my shoulder with the 500/4 attached a lot), the new secure locking system is a welcome addition.
  • Max load is doubled (25kg now).
  • The entire tripod seems to dampen vibrations much quicker and better than the 1325 did.
  • Weight hook at the bottom of the top plate. Great to hang your heavy bag (or a beanbag) here in windy conditions. I really appreciate this addition.
  • A carabiner hole on the rim of the top plate (I prefer to attach the strap with a carabiner than wrapping around the head).
  • Leg angle stops can be pulled out from the outside (there are finger recesses on both sides), so you don’t have to push them out from inwards. Nice!

The only negative thing I found was that after removing the top plate, some of the exposed edges were quite rough. Actually they were not deburred. I thought that they will scar my fingers in the worst moment, so picked up a file and deburred those edges.

I hope that this product will prove to be at least as reliable as it’s predecessor. It’ll stay with me for the upcoming decade – or even more.

Filed Under: Photo Equipment Tagged With: , ,

First Flight Shooting with the 5D3

July 1, 2012 by

Yesterday evening I went out to Lake Tisza for a two hour flight shooting test. Courtship feeding was in progress these days in the whiskered tern colony and I thought that that could be a good test for auto focus capabilities, and a chance for me to learn to use the new AF system.

I’ve used two lenses: a 500mm f/4L IS USM with the 1.4x II extender, and a 400mm f/5.6L USM. Both lenses had an 600EX flash attached to a bracket with a Better Beamer – for just a gentle touch of fill light. I shot handheld with both lenses. Yes, it is not the funniest thing to follow fast moving birds with about 6kg of glass and metal, but wanted to know how it feels with the smaller body of the 5D3.

Self-Shadow

The new AF system worked quite well. It was as good if not better than the aging system in my 1D Mark II. Coming from the 1D2, the ability to show the active AF points in the finder was a real boon – I could instantly refocus when the system catched the otherwise busy background.

I was surprised that I did not feel the need for the grip when shooting with the 500mm. Although the 5D3 is not that much bigger than the 5D2 was, it fits my largish hand much better. I was able to grip the body securely and maneuver the 500mm lens with it. I was even more surprised that with the 400mm I could use the grip – the rig felt somehow nose-heavy. Or I just missed the hand strap. This point needs more testing. But at the moment I think I will work without the grip for at least a month or so.

Images are first class, there’s nothing to complain about them. I really love the huge 22 megapixel files – I can crop them as needed later without risking my usual A3+ sized bird print quality.

For those interested in the f/8 thing. I started to avoid shooting with the 2x teleconverter since the 1DX specs arrived – just to see if there’s anything I miss with it. Actually I have gained a lot – better image quality (the 2x II is quite a lemon). I also had to push myself and move closer to the birds. It proved to be great fun – the closer you are the more you became a part of their lives. Bottom line: don’t feel a burning need for the f/8 focusing capability at the moment. I just let those images that would need the 2x go.

Courtship Gift

Regarding the bad things. There a few of course. The most irritating of them is the auto brightness control algorithm. On several occasions the screen remained so dark that I can’t see a thing on it (it was golden hour, so the sunlight was quite muted). When I pressed the play button sometimes brightness came back. So I ended up turning off the auto thing and controlling brightness myself.

Another observation that makes me sad is the inability to judge sharpness from the LCD. I do AF microadjustment check/recalibration before each shot for the actual working distance. But frankly I was unable to judge where the focal plane is without cranking up JPEG sharpening seriously. But that have a negative side effect on the histogram and blinkies. I would like to see the LCD image properly sharpened for the camera’s display (or even a custom function that would allow slightly over-sharpening it so that one can judge sharpness much easier) without affecting the JPEGs and the histogram. Maybe in the 5D4 or 5…

All in all I really love the 5D3. It is a joy to work with this camera. Is it perfect? Far from it. But if I treat is as a tool then I’m sure it will produce some great images in the upcoming 3-4 years.

Filed Under: My Photos, Photo Equipment Tagged With: , , ,
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