We've provided this printable version of our review for your convenience. Please remember that your shopping clicks support this site. If you think this camera is a good choice for you, please consider returning to the link below to check prices and make a purchase via our shopping links.

Also note that this is just one of the pages from this review. Full reviews have several pages with complete analysis of the many test shots we take with each camera. Feel free to download and print them out to see how the camera will perform for you.

Full Review at: http://www.imaging-resource.com/PRODS/E1DMK4/E1DMK4A.HTM

Like this camera?
Save money online!
Prices as of 08/21/2014
Save Money!
Canon 1D Mark IV

No price data available. Check back soon.

Canon EOS-1D Mark IV Image Quality


Color

Saturation & Hue Accuracy
Very good saturation and excellent hue accuracy.

In the diagram above, the squares show the original color, and the circles show the color that the camera captured. More saturated colors are located towards the periphery of the graph. Hue changes as you travel around the center. Thus, hue-accurate, highly saturated colors appear as lines radiating from the center.
Saturation. The Canon EOS-1D Mark IV pushes reds, oranges, greens and blues a bit, but actually undersaturates aqua and cyan a small amount. Overall, saturation is very good and the somewhat vibrant color will most likely be very appealing to many users. Most consumer digital cameras produce color that's more highly saturated (more intense) than found in the original subjects. This is simply because most people like their color a bit brighter than life.

Skin tones. Flesh tones shot with the Canon 1D Mark IV appeared quite natural, with appropriate saturation levels and accurate color, though slightly on the cool side. When white-balance was adjusted to match the lighting, skin-tones were warmer, with a "healthy looking glow". Where oversaturation is most problematic is on Caucasian skin tones, as it's very easy for these "memory colors" to be seen as too bright, too pink, too yellow, etc.

Hue. With an average "delta-C" color error of only 4.35 after correction for saturation, the Canon 1D Mark IV's hue accuracy is among the best we've ever tested. There were the usual shifts in cyan toward blue, red toward orange, and orange toward green, but they are very minor. (The cyan to blue shift is very common among the digital cameras we test; we think it's a deliberate choice by camera engineers to produce better-looking sky colors.) Excellent hue accuracy overall. Hue is "what color" the color is.

Saturation Adjustment
The Canon 1D Mark IV offers a total of nine saturation settings, four above and four below the default saturation. This covers a very wide range of saturation levels, about as wide a range as you're likely to find photographically useful, apart from special effects that are arguably better achieved in software. As it should, the 1D Mark IV's saturation adjustment affects only the saturation, leaving the contrast of the image more or less unaltered. (In some cameras, saturation tends to affect contrast, and vice versa.) The fine steps between settings mean you can program the camera to just the level of saturation you prefer. Well done.

Saturation Adjustment Examples
-4 -2 0 +2 +4

The table above shows alternate settings including the default as well as the two extreme saturation settings. Click on any thumbnail above, then click again to see the full-sized image.

Sensor

Exposure and White Balance

Indoors, incandescent lighting
Auto and Incandescent settings both struggle with household incandescent lighting, though Manual and 2,600 Kelvin white balance settings produce much more neutral images. Average exposure compensation required.

Auto White Balance
+0.3 EV
Incandescent White Balance
+0.3 EV
Manual White Balance
+0.3 EV
2,600 Kelvin White Balance
+0.3 EV

Indoors, under incandescent lighting, the Canon 1D Mark IV's Auto white balance setting really struggled to produce a decent-looking image. Unfortunately, this is quite common among cameras we've tested, but disappointing nonetheless, particularly in a premium-grade professional SLR.

The Canon 1D Mark IV's Incandescent setting did a little better, but the resulting image was still too warm for our tastes. (Some may feel that it successfully conveys the warmth of the original lighting, but we'd personally like a more neutral treatment.) This is undoubtedly correct for a camera aimed at professionals, whose incandescent studio lighting is generally balanced to 3,200 Kelvin. Note, too, that the Canon 1D Mark IV's white balance system permits very flexible manual adjustment of each of its presets, so the Incandescent setting could easily be tweaked to match the requirements of household lighting of the type used here.

The Manual and 2,600 Kelvin white balance options were very similar, both producing fairly neutral images. Manual white balance was the most accurate, with the 2,600 Kelvin setting being just a touch cool. The Canon 1D Mark IV required a positive exposure compensation of 0.3 EV for this shot, which is average for this shot.

(Our test lighting for this shot is a mixture of 60 and 100 watt household incandescent bulbs, a pretty yellow light source, but a very common one in typical home settings here in the U.S.)

Outdoors, daylight
Color and saturation are very good, though a tendency towards slightly cool color balance and slightly high contrast under harsh lighting. About average exposure accuracy.

Auto White Balance,
+0.7 EV
Auto White Balance,
0 EV

Outdoors, the Canon 1D Mark IV tended toward a slightly cool color balance, as you can see by the skin tones in the above left shot, though overall color was generally excellent. The Canon 1D Mark IV performed about average in terms of exposure, requiring the typical amount of positive compensation (0.7 EV) we're accustomed to seeing among digital cameras for our "Sunlit" portrait shot. The Canon 1D Mark IV's default contrast is a little high, producing some washed-out highlights and dark shadows under the deliberately harsh lighting of our portrait test shown above left, though the camera's contrast and highlight tone priority settings do help tame the highlights quite a bit. See below for examples of this. The far-field house shot (above right) was also a touch cool, and had quite a few blown highlights in the white trim at the default exposure, though few shadows were lost.

See full set of test images with explanations
See thumbnails of all test and gallery images

Resolution
Very high resolution, 1,900 ~ 2,000 lines of strong detail.

Strong detail to
2,000 lines horizontal
In-Camera JPEG
Strong detail to
1,900 lines vertical
In-Camera JPEG
Strong detail to
2,000 lines horizontal
ACR Converted RAW
Strong detail to
2,000 lines vertical
ACR Converted RAW

Our laboratory resolution chart showed the Canon 1D Mark IV's images with sharp, distinct line patterns down to about 2,000 lines per picture height horizontally and about 1,900 lines vertically. Extinction occurred at about 3,000 lines in both directions. We weren't able to do much better with Adobe Camera Raw converted .CR2 files; perhaps just a bit better in vertical direction, but some of the apparent increase is due to a reduction in moiré patterns caused by oversharpening in the camera JPEG. Use these numbers to compare with other cameras of similar resolution, or use them to see just what higher resolution can mean in terms of potential detail.

See full set of test images with explanations
See thumbnails of all test and gallery images

Sharpness & Detail
Very good sharpness and lots of detail, though some sharpening artifacts are visible. Slight loss of detail to noise reduction processing even at low ISOs, but better than average.

With default sharpening settings,
the Canon 1D Mark IV's JPEG
files show some minor sharpening artifacts. With its 16 megapixel
resolution, this yields crisp-
looking prints to quite large sizes.
Subtle detail: Hair
Noise suppression blurs
detail in areas of subtle contrast,
as in the darker parts of
the model's hair here.

Sharpness. The Canon 1D Mark IV's 16-megapixel sensor captures a lot of image detail when coupled with a good lens, but images are slightly oversharpened at default settings. Some minor edge-enhancement artifacts are visible around high-contrast edges such as the branches shown in the crop above left. (The above crop of our far-field house shot was taken with Canon's very sharp EF 35mm f/2 len at f/8.) Edge enhancement creates the illusion of sharpness by enhancing colors and tones right at the edge of a rapid transition in color or tone.

Detail. The crop above right shows some detail loss due to noise suppression, with lower-contrast hairs being blurred together, but it's less than we're accustomed to seeing. A very good performance here. Noise-suppression systems in digital cameras tend to flatten-out detail in areas of subtle contrast. The effects can often be seen in shots of human hair, where the individual strands are lost and an almost "watercolor" look appears.

RAW vs In-Camera JPEGs
As mentioned above, the Canon 1D Mark IV does a very good job of capturing sharp, detailed JPEGs when coupled with a good lens, but as is usually the case, slightly more detail can be preserved by carefully processing its RAW files, with fewer sharpening artifacts.

In the table above, mousing over a link at the bottom will load the corresponding crop in the area above, and clicking on the link will load the full resolution file. Examples include in-camera Fine JPEG, RAW file processed through Canon's Digital Photo Professional (DPP) software, and finally, a RAW file processed through Adobe Camera Raw (ACR) version 5.7, then sharpened in Photoshop. For the Canon EOS 1D Mark IV's images above, we set DPP's sharpening operator to 75 as default settings were a touch soft, and used strong but tight 300% unsharp masking with an 0.3 pixel radius for the ACR converted file.

Manufacturer software often doesn't find as much detail as does Adobe Camera Raw, but Canon's DPP does better than most. The images processed through DPP and ACR both show more detail than the in-camera JPEG.

ISO & Noise Performance
Low noise and excellent detail up to ISO 1,600. Noise vs detail performance very good for the resolution.

Default High ISO Noise Reduction
ISO 50 ISO 100 ISO 200
ISO 400 ISO 800 ISO 1,600
ISO 3,200 ISO 6,400 ISO 12,800
ISO 25,600 ISO 51,200 ISO 102,400

The Canon 1D Mark IV's images are quite clean through ISO 200, with just a bit luminance noise seen in the shadows. We start to see a very fine, tight "grain" pattern at ISO 400, but detail is only slightly affected in the hair and fabric, with low levels of chroma noise in the shadows. The grain is slightly more evident at ISO 800, but detail remains very strong. At ISO 1,600, we begin to see moderate amounts of luminance noise, but it's still a fine, tight grain pattern, giving the image a film-like look. At ISO 3,200, noise grain becomes coarser, resulting in a more noticeable drop in detail, though detail is still pretty good. ISO 6,400 continues this trend, with stronger noise, both luminance and chrominance, but again, detail is holding fairly well. Noise and the effects of noise reduction really become apparent at ISO 12,800 and above, with progressively stronger blurring, brighter noise pixels and heavy chroma blotching to the point where ISO 102,400 is useful only in emergency situations. That said, the Canon 1D Mark IV's noise reduction processing generally does a better job of preserving fine detail than many cameras. Overall, a very good performance for a camera with a 16-megapixel APS-H size sensor, though not as good as the current high-ISO champ, the 12-megapixel full-frame Nikon D3S.

We're of course pixel-peeping to an extraordinary extent here, since 1:1 images on an LCD screen have little to do with how those same images will appear when printed. See the Print Quality section below for our evaluation of maximum print sizes at each ISO setting.

A note about focus for this shot: We shoot this image at f/4, using one of three very sharp reference lenses (70mm Sigma f/2.8 macro for most cameras, 60mm f/2.8 Nikkor macro for Nikon bodies without a drive motor, and Olympus Zuiko 50mm f/2.0 for Four Thirds and Micro Four Thirds bodies). To insure that the hair detail we use for making critical judgements about camera noise processing and detail rendering is in sharp focus at the relatively wide aperture we're shooting at, the focus target at the center of the scene is on a movable stand. This lets us compensate for front- or back-focus by different camera bodies, even those that lack micro-focus adjustments. This does mean, though, that the focus target itself may appear soft or slightly out of focus for bodies that front- or back-focused with the reference lens. If you click to view the full-size image for one of these shots and notice that the focus target is fuzzy, you don't need to email and tell us about it; we already know it. :-) The focus target position will simply have been adjusted to insure that the rest of the scene is focused properly.

Extremes: Sunlit and low light tests
Very high resolution with strong overall detail, but slightly high default contrast. Highlight Tone Priority and contrast adjustment options do a great job of dealing with tough lighting, though. Excellent low-light performance; able to produce bright, well-focused images at our lowest light levels unassisted.

+0.3 EV +0.7 EV +1.0 EV

The Canon EOS 1D Mark IV produced slightly high contrast with some washed-out highlights and deep shadows under the deliberately harsh lighting of the test above. The model's face was a little dim at the +0.3 EV setting, so we preferred the image with +0.7 EV of exposure compensation, which resulted in quite a few clipped highlights in the shirt and flowers, though there weren't too many lost shadows. Exposure compensation of +1.0 EV resulted in a too many clipped highlights for our tastes, though some shooters may prefer the +1.0 EV image for its brighter skin tones.

Because digital cameras are more like slide film than negative film (in that they tend to have a more limited tonal range), we test them in the harshest situations to see how they handle scenes with bright highlights and dark shadows, as well as what kind of sensitivity they have in low light. The shot above is designed to mimic the very harsh, contrasty effect of direct noonday sunlight, a very tough challenge for most digital cameras. (You can read details of this test here. In actual shooting conditions, be sure to use fill flash in situations like the one shown here; it's better to shoot in open shade whenever possible.)

Highlight Tone Priority Example
Off (default)
+0.3 EV
On
+0.3 EV
Highlight Retention
Shadow Detail, R.H.S. Brightened in Photoshop
(Levels control, highlight slider down to 50)

Highlight Tone Priority
The Canon 1D Mark IV's Highlight Tone Priority (HTP) option did an excellent job of preserving highlight detail, as shown above, though it rendered the model's face a little dim. (In hindsight, it would have been better to shoot this series with more positive exposure compensation.) Both shots above were captured at the same +0.3 EV exposure, the only difference being that HTP was enabled for the shot on the right. (Which necessarily increases the ISO to 200, part of how HTP works.) The result is evident even in the histograms and crops above; the full-size images clearly show the superior highlight preservation when HTP is enabled, while shadow detail is left relatively untouched. The right side of the Shadow Detail crops above have had their histogram levels adjusted equally in Photoshop to reveal the increase noise in the HTP-On case. The increase in noise is because the ISO is boosted from 100 to 200. Except in the very deepest shadows, though, overall noise is so low at ISO 200 that this is really a negligible trade-off for all but the most critical applications.


Contrast Adjustment Examples
-4 -2 0 +2 +4

The Canon 1D Mark IV's contrast-adjustment control also does an excellent job with very difficult lighting like this. It offers a very broad range of control in usefully fine gradations, and does a good job of adjusting contrast without affecting color saturation in the process. (As noted earlier regarding saturation adjustment, something that not all cameras manage to do.) The table above shows alternate settings including the default as well as the two extreme contrast settings. Click on any thumbnail above, then click again to see the full-sized image.


Automatic Lighting Optimization Examples
Low Standard Strong
Off

Automatic Lighting Optimization
Like other recent Canon SLRs, the EOS-1D Mark IV offers three selectable levels of ALO: Low, Standard and Strong, plus Off. Standard is the default level. All four shots above were taken with the same exposure settings. As you can see, ALO has the effect of shifting shadows and mid-tones in the histograms to the right, lightening the overall image without clipping too many additional highlights, though the results can be quite subtle.

Because digital cameras are more like slide film than negative film (in that they tend to have a more limited tonal range), we test them in the harshest situations to see how they handle scenes with bright highlights and dark shadows, as well as what kind of sensitivity they have in low light. The shot above is designed to mimic the very harsh, contrasty effect of direct noonday sunlight, a very tough challenge for most digital cameras. (You can read details of this test here.)


  1 fc
11 lux
1/2 fc
5.5 lux
1/4 fc
2.7 lux
1/8 fc
1.3 lux
1/16 fc
0.67 lux
1/16fc
No NR
ISO
50
Click to see E1DMK4LL0000503.JPG
2.6s
f2.8
Click to see E1DMK4LL0000504.JPG
5.2s
f2.8
Click to see E1DMK4LL0000505.JPG
10.4s
f2.8
Click to see E1DMK4LL0000506.JPG
20.7s
f2.8
Click to see E1DMK4LL0000507.JPG
32s
f2.8
Click to see E1DMK4LL0000507XNR.JPG
32s
f2.8
ISO
100
Click to see E1DMK4LL0001003.JPG
1.3s
f2.8
Click to see E1DMK4LL0001004.JPG
4s
f2.8
Click to see E1DMK4LL0001005.JPG
8s
f2.8
Click to see E1DMK4LL0001006.JPG
16s
f2.8
Click to see E1DMK4LL0001007.JPG
32s
f2.8
Click to see E1DMK4LL0001007XNR.JPG
32s
f2.8
ISO
200
Click to see E1DMK4LL0002003.JPG
0.6s
f2.8
Click to see E1DMK4LL0002004.JPG
2s
f2.8
Click to see E1DMK4LL0002005.JPG
4s
f2.8
Click to see E1DMK4LL0002006.JPG
8s
f2.8
Click to see E1DMK4LL0002007.JPG
16s
f2.8
Click to see E1DMK4LL0002007XNR.JPG
16s
f2.8
ISO
400
Click to see E1DMK4LL0004003.JPG
0.3s
f2.8
Click to see E1DMK4LL0004004.JPG
1s
f2.8
Click to see E1DMK4LL0004005.JPG
2s
f2.8
Click to see E1DMK4LL0004006.JPG
4s
f2.8
Click to see E1DMK4LL0004007.JPG
8s
f2.8
Click to see E1DMK4LL0004007XNR.JPG
8s
f2.8
ISO
800
Click to see E1DMK4LL0008003.JPG
1/6s
f2.8
Click to see E1DMK4LL0008004.JPG
0.5s
f2.8
Click to see E1DMK4LL0008005.JPG
1s
f2.8
Click to see E1DMK4LL0008006.JPG
2s
f2.8
Click to see E1DMK4LL0008007.JPG
4s
f2.8
Click to see E1DMK4LL0008007XNR.JPG
4s
f2.8
ISO
1600
Click to see E1DMK4LL0016003.JPG
1/12s
f2.8
Click to see E1DMK4LL0016004.JPG
1/4s
f2.8
Click to see E1DMK4LL0016005.JPG
0.5s
f2.8
Click to see E1DMK4LL0016006.JPG
1s
f2.8
Click to see E1DMK4LL0016007.JPG
2s
f2.8
Click to see E1DMK4LL0016007XNR.JPG
2s
f2.8
ISO
3200
Click to see E1DMK4LL0032003.JPG
1/25s
f2.8
Click to see E1DMK4LL0032004.JPG
1/8s
f2.8
Click to see E1DMK4LL0032005.JPG
1/4s
f2.8
Click to see E1DMK4LL0032006.JPG
0.5s
f2.8
Click to see E1DMK4LL0032007.JPG
1s
f2.8
Click to see E1DMK4LL0032007XNR.JPG
1s
f2.8
ISO
6400
Click to see E1DMK4LL0064003.JPG
1/49s
f2.8
Click to see E1DMK4LL0064004.JPG
1/16s
f2.8
Click to see E1DMK4LL0064005.JPG
1/8s
f2.8
Click to see E1DMK4LL0064006.JPG
1/4s
f2.8
Click to see E1DMK4LL0064007.JPG
0.5s
f2.8
Click to see E1DMK4LL0064007XNR.JPG
0.5s
f2.8
ISO
12800
Click to see E1DMK4LL0128003.JPG
1/99s
f2.8
Click to see E1DMK4LL0128004.JPG
1/32s
f2.8
Click to see E1DMK4LL0128005.JPG
1/16s
f2.8
Click to see E1DMK4LL0128006.JPG
1/8s
f2.8
Click to see E1DMK4LL0128007.JPG
1/4s
f2.8
Click to see E1DMK4LL0128007XNR.JPG
1/4s
f2.8
ISO
25600
Click to see E1DMK4LL0256003.JPG
1/197s
f2.8
Click to see E1DMK4LL0256004.JPG
1/64s
f2.8
Click to see E1DMK4LL0256005.JPG
1/32s
f2.8
Click to see E1DMK4LL0256006.JPG
1/16s
f2.8
Click to see E1DMK4LL0256007.JPG
1/8s
f2.8
Click to see E1DMK4LL0256007XNR.JPG
1/8s
f2.8
ISO
51200
Click to see E1DMK4LL0512003.JPG
1/395s
f2.8
Click to see E1DMK4LL0512004.JPG
1/128s
f2.8
Click to see E1DMK4LL0512005.JPG
1/64s
f2.8
Click to see E1DMK4LL0512006.JPG
1/32s
f2.8
Click to see E1DMK4LL0512007.JPG
1/16s
f2.8
Click to see E1DMK4LL0512007XNR.JPG
1/16s
f2.8
ISO
102400
Click to see E1DMK4LL1024003.JPG
1/790s
f2.8
Click to see E1DMK4LL1024004.JPG
1/256s
f2.8
Click to see E1DMK4LL1024005.JPG
1/128s
f2.8
Click to see E1DMK4LL1024006.JPG
1/64s
f2.8
Click to see E1DMK4LL1024007.JPG
1/32s
f2.8
Click to see E1DMK4LL1024007XNR.JPG
1/32s
f2.8

Low light. The Canon 1D Mark IV performed very well on the low-light test, capturing bright images at the lowest light level (1/16 foot-candle), even with the lowest sensitivity setting (ISO 50). Exposure was consistent and fairly accurate, using Aperture Priority AE mode. (We often need to resort to Manual exposure at these light levels, but not so with the Mark IV.) As expected, noise increases as ISO goes up and light levels go down, but remains surprisingly low up to ISO 1,600. Some hot pixels appear when long-exposure noise reduction is turned off (right-most column), but that's quite normal. There is some horizontal banding visible, but only at ISO 25,600 and above. The bottom right hand corner of the image shows what looks to be heat blooming (the localized increase in red pixels) at very high ISOs and low-light levels, which could be the result of heat radiating from a warm component located close to the sensor there. Color balance was pretty neutral with Canon 1D Mark IV's Auto white balance setting, though a slightly reddish cast appeared as light levels dropped.

The Canon EOS-1D Mark IV's phase-detect autofocus system was able to focus on the subject in light levels below the minimum 1/16 foot-candle we normally test to unassisted, which is excellent. As with most professional SLRs, the 1D Mark IV does not have a built-in autofocus assist lamp, using instead the AF assist lamp provided when a Speedlite flash is mounted in the hotshoe. The 1D Mark IV's contrast-detect autofocus in Live View mode struggled in low-light though, often confirming focus when focus was not achieved.

As always, keep in mind that the longer shutter speeds here demand the use of a tripod to prevent any blurring from camera movement. (A useful trick is to just prop the camera on a convenient surface, and use its self-timer to release the shutter. This avoids any jiggling from your finger pressing the shutter button, and can work quite well when you don't have a tripod handy.)

How bright is this? The one foot-candle light level that this test begins at roughly corresponds to the brightness of typical city street-lighting at night. Cameras performing well at that level should be able to snap good-looking photos of street-lit scenes.

NOTE: This low light test is conducted with a stationary subject, and the camera mounted on a sturdy tripod. Most digital cameras will fail miserably when faced with a moving subject in dim lighting. (For example, a child's ballet recital or a holiday pageant in a gymnasium.) Digital SLRs like the Canon 1D Mark IV do much better than point & shoots, but you still shouldn't expect a quick autofocus lock with moving subjects.

Output Quality

Print Quality
Impressive print quality; good color, very sharp, detailed prints up to 20x30 inches.

Printed JPEGs with all settings at their defaults and ISO at 50 yield very sharp 20x30-inch prints with good color and high contrast.

ISO 100 shots are ever so slightly softer at 20x30, but the difference requires squinting, and it's difficult to be sure there's any difference at all.

ISO 200 images also look superb at 20x30.

ISO 400 files also look just great at 20x30.

ISO 800 files--holding this pro camera to a higher standard here--look better at 16x24, but they're also quite amazingly good at 20x30.

ISO 1,600 shots show the slightest hints of grain in the shadows, but are still quite remarkable at 16x24. Difficult patterns like the red leaf fabric and Pure Brewed label start to soften slightly, but not badly.

ISO 3,200 files show more grain, more softness, but are still quite good at 16x24.

ISO 6,400 images show enough noise and noise suppression softening for a reduction to 13x19 inches. Contrast is also increased, with very dark darks, and deepening shadows. The red swatch is really starting to distort as well.

ISO 12,800 shots start to show salt and pepper noise in the shadows, and the red swatch is blurry, but overall it's good at 11x14 inches.

ISO 25,600 is a little dicey at 11x14 inches, looking more like a colorized B&W, with a slight hint of chroma blotches in the shadows and solid colors. Reducing to 8x12 inches makes a more usable print. Darks continue to deepen.

ISO 51,200 shows more chroma noise and grain, but it's not a terrible appearance at 8x12. Still, it's more up to the standard we look for printed at 5x7 inches.

ISO 102,400 has even more chroma noise and grain, looking more like a very festive birthday cake with sprinkles, and darks are essentially clipped blacks. It's usable at 4x6, but not excellent. I'd take it and remove the color with a filter, though.

RAW is obviously where you'd want to start for optimum quality from ISO 3,200 up, but the potential is huge. Overall it's another impressive performance from a Canon pro camera.

Testing hundreds of digital cameras, we've found that you can only tell just so much about a camera's image quality by viewing its images on-screen. Ultimately, there's no substitute for printing a lot of images and examining them closely. For this reason, we now routinely print sample images from the cameras we test on our Canon Pro9000 Mark II studio printer, and on the Canon Pixma MP610 here in the office. (See the Canon Pixma Pro9000 Mark II review for details on that model.)