The Great Compromise : Canon EOS 60D

The new Canon 60D, pictured with a battery grip.

Since the arrival of the Canon EOS 7D and subsequent release of the T2i / 550D there has been a gap in the Canon lineup. Buying the 50D no longer seemed practical to many advanced amateurs, since it was so outclassed by the features of the T2i, but the price of the 7D put it just beyond the range of what many were willing to spend (and the weight and size beyond what they were willing to tote around). Yet, the advanced amateur still yearned for more features and ease of control, and frankly, more status than is offered by the entry level “Rebel” line.

The Canon EOS 60D, announced about a week ago, is clearly intended to fill this gap. Probably available in September, its expected price of $1099 falls nicely between the Rebel T2i ($799) and the 7D ($1535). Its features, also, are largely intermediate between the two cameras that were already very similar. The controls are similar, but not identical, to the 7D, while the construction is much more in line with the T2i than the 7D (or the 50D, for that matter).

Lets take a quick look at the differences, side-by-side:

	Canon 60D	Canon 7D	Canon Rebel T2i (550D)
Price	$1099	$1599	$799
Body Material	Polycarbonate & Stainless Steel	Magnesium Alloy	Polycarbonate resin & fiberglass with Stainless Steel
LCD Monitor Size	Articulated, 3.0", 1,040,000 pixels, 3:2 aspect ratio	3.0" 920,000 pixels, 4:3 aspect ratio	3.0" 1,040,000 pixels
Sensor	18 Megapixel CMOS	18 Megapixel CMOS	18 Megapixel CMOS
Crop Factor	1.6	1.6	1.6
Sensitivity (ISO Range)	100-6400 +12800	100-6400 +12800	100-6400 +12800
Metering System	63 Zone (point linked) Evaluative 6.5% Partial Metering 2.8% Spot	63 Zone (point linked) Evaluative 9.4% Center Weighted 2.3% Spot	63 Zone (point linked) Evaluative 9% Center Weighted 4% Spot
Focusing Points	9 cross-type points	19-point dual diagonal cross-type	9 Points, 1 cross-type at center
AF Working Range	-.05 EV to 18 EV	-.05 EV to 18 EV	-.05 EV to 18 EV
Still Photo Frame Rate	5.3 frames per second	8 frames per second	3.7 frames per second
Maximum Burst Duration	58 jpg 16 RAW	94 jpg 15 RAW	37 jpg 6 RAW
Exposure Compensation	1/2 or 1/3 stops via thumb-wheel	1/2 or 1/3 stops via thumb-wheel	1/2 or 1/3 stops via dedicated button + dial
Shutter Speeds	30 - 1/8000th sec.	30 - 1/8000th sec.	30 - 1/4000th sec.
Standard Flash Sync Speed	1/250th sec.	1/250th sec.	1/200th sec.
Highest Video Resolution	1080p	1080p	1080p
Max Video Frame Rates	30 fps at 1080p 60 fps at 720p	30 fps at 1080p 60 fps at 720p	30 fps at 1080p 60 fps at 720p
Media Type	SD / SDHC / SDXC	Compact Flash	SD / SDHC / SDXC
Weight	755g	820g	530g
Viewfinder Coverage	96% Frame, .95x magnification	100% 1.0x magnification	95% Frame .87x magnification

Probably the most important change between the 60D and the previous models in its line is that it does NOT have a metal body. Instead, Canon opted for a lighter, less expensive polycarbonate body which, although lighter than the magnesium 7D, still feels quite sturdy.

And perhaps just as significant, Canon has designed the 60D with a fully articulated, 3″ LCD screen for use in “Live” viewing mode and for video… the first ever on an SLR. Since I never use “Live” mode, and rarely use video, it’s hard for me to get excited about this feature, but perhaps for some photographers out there, it’s just what they’ve been waiting for.

The Deciding Factors

All three cameras share the same basic CMOS sensor, providing very similar resolution and high-ISO performance. All three cameras share the same video capabilities. So which should you get?

Buy the Canon 7D ($1535) if :

1. You are a professional or use your camera daily. It is the most robust of the three, with a magnesium alloy body that will stand up to the wear and tear of daily use. This is especially important if you’re a journalist and your camera equipment suffers undue abuse.
2. If you are primarily an action or sports photographer. The dual digic-4 processors of the 7D make it the fastest, and its 19 cross-type point focusing system is the most reliable in difficult situations.
3. Because the 7D has two Digic-4 processors, it is likely to be able to handle high definition video files better than single processor models, though I’d be surprised if there’ll be much of a practical difference.

Buy the Canon 60D ($1099) if:

1. You want the 7D but can’t afford it. The differences are minimal, and a good photographer can easily work around them.
2. You shoot a lot of video and the articulated LCD would be helpful to you.
3. If you’re upgrading from the Rebel line and would like to keep using your SD cards.
4. You shoot a lot of action. The 9 cross-type focusing points are a major improvement over the previous cameras in this series (40D, 50D, etc) and the Rebel series, and will help tremendously when focusing on action or in low contrast situations.
5. You’re looking for a lighter alternative to the 7D.

Buy the Canon Rebel T2i / 550D ($799) if:

1. You’re on a tight budget but still want an awesome 18 megapixel sensor, full features, and 1080p video.
2. If you’re looking for a lightweight camera for travel and will be able to treat it with a bit of care, or a backup for your usual camera.
3. If you primarily shoot portraits or products rather than action, or shoot landscapes/art.

Mac or PC? Actually, I don’t believe that it really makes much of a difference, as long as you know what you’re doing with what you have. But that’s not the point of this post. I just ran across a bit of information that struck me as interesting.

According to NetMarketShare, which seems to produce reliable numbers, MAC OS makes up a mere 5.26% of the total market share of operating systems, compared to 91.23% for Windows. That seemed a little bit low to me, so I checked the stats on a couple of websites that I’ve built, and I’ve found that MAC tends to represent about 8-10% of the visits on most of them.

This site, however, is different. This month, so far, 28.5% of the visitors are MAC users, and last month, a full 29.6%. OK, so it’s just confirmation of what we already know… photographers (and other visual artists) disproportionately prefer MAC, although the vast majority are still using PCs. Still, I didn’t expect there to be such a strong showing for Macs on a blog like this, so I thought I’d mention it.

And of course, this post gives everyone a good excuse to tell me how much they love their Mac, as Mac people are so zealous to do I learned Photoshop on Mac originally, but have used a PC most of the time for the past 10 years.

Which is the best Canon SLR for Video Use? How do they differ?

[For non-video related comparisons of these cameras, please see my previous articles : 5D Mark II vs. the 7D and the 7D vs the T2i.]

Currently, the Canon EOS 5D Mark II is unrivaled in the world of SLRs for professional quality video production.  For those of you who watch the FOX medical drama “HOUSE”, you may be interested to learn that the recent season finale (May 2010) was shot entirely with Canon 5D Mark IIs. The 5D’s closest competitors, though, are also Canon SLRs, and less expensive ones at that.  These are the Canon EOS 7D and the Canon T2i / 550D.  There are a few fundamental differences between these cameras and the 5D which may make them more attractive to some film makers, while others may be deterred. I’ll quickly discuss these differences below. As always, additional information and further questions  are welcome!

Depth of Field

The fundamental difference, of course, is the sensor size. The 5D carries a full-frame sensor, while the 7D and T2i use APS-C (ie, 1.6x crop) sensors. For video, however, this creates a completely different set of problems than it does for still photography. Image quality is NOT a significant difference, as 1080p HD video (1920 x 1080 pixels) is only 2 megapixels. In each of these cameras, only about 10% of the data that can be captured by the sensor will be used, so issues of lens resolution (discussed previously regarding the 7D and 50D), diffraction, etc, that plague the world of fine art photography are simply not field-relevant with video; video resolution is too low to reproduce these problems.

The main issue with video is depth of field. Since HD video resolution is so low, comparatively speaking,  most video cameras have very small sensors… many of them less than 1/4 the size of an APS-C sensor. The smaller the sensor, the greater the depth of field… so most consumer grade video cameras produce video in which the backgrounds are relatively sharp in comparison to the subjects, which looks very distinctive and, frankly, cheap. Professional grade video cameras use larger sensors and can use depth of field more creatively, but cost a small fortune. Or a large fortune, in many cases (hundreds of thousands of dollars).

Many professional grade video cameras, costing $100,000 or more, use small 2/3″ sensors. The Sony HDW-F900R CineAlta is a perfect example.

And this is where the Canon SLRs excel. They have large sensors with incredible lenses, and can produce depth of field effects (separation of subjects or subject/background) just as well as film cameras of the past and modern production video cameras. Even APS-C sized sensors (Canon’s are about 22.2 x 14.8mm ) in Cameras such as the 7D are much larger than most video camera sensors (the Red One is an exception, with a sensor about the size of an APS-C, and a camera setup can be had for only about $20,000).

Since the APS-C size sensors of the 7D and T2i are both about the same size as 35mm movie film frames (which are smaller than 35mm still photo frames), they produce a shallow depth of field that is very similar to film-based movie cameras. The 5D Mark II has an even larger sensor, and therefore has a significantly shallower depth of field, at least potentially. Regardless of the camera, the actual depth of field will still depend on the focal length of the lens (ie, 24mm lens vs. 200mm lens) and the aperture at which the lens is used.  Since all of the Canon cameras can be used with the full line of EF lenses, many of which utilize a maximum aperture of f1.4-2.8, there should be little difficulty in achieving very smooth, shallow depth of field, as long as it’s not too bright to use the wide apertures.  Shutter speeds higher than 1/250th of a second can produce a choppy looking effect because each individual frame loses motion blur and becomes too sharp.

Since movie film travels vertically (for typical formats), its widest dimension is actually about the same as the narrow dimension of a full frame still photograph.

Video Features

The three cameras in question are remarkably similar when it comes to video functionality. The following table highlights the many similarities and a few of the differences between the three models.

Firmware

One of the great things about using a camera that is controlled by software is that, in this digital age, it opens the door for the possibility of 3rd party improvements. When the Canon 5D Mark II was introduced, film makers were immediately enchanted by its potential in the industry, but the camera was missing several important features for serious video use. Consequently, a team of clever programmers/film makers got together and created a firm-ware upgrade for the 5D called “Magic Lantern”.

Magic Lantern isn’t a firmware replacement. It is, essentially, a sidecar; a piece of software that runs along side the 5D’s native firmware. Full details about Magic Lantern can be found on their website, but it is a FREE download and can be used by anyone willing to try it.

Currently, Magic Lantern offers the following features for the 5D Mark II:

• On-Screen Audio Meters
• Zebra Stripes
• Disables Audio AGC
• On-Screen Crop Marks for different aspect ratios

Magic Lantern for the 7D is under development, and is expected to be available soon. You can check the progress on the Magic Lantern 7D development website. Although it is technically possible, I have not yet seen any mention of devel0pment for the Rebel T2i / 550D. Since there are so many similarities between the 7D and 550D, it is quite possible that once the firmware for the former is released, it will be modified to work with the latter.

Conclusions

For the moment, the 5D Mark II is the clear winner for true production work, due in large part to Magic Lantern. However, the dedicated video controls of the 7D (and the price tag) make the 7D a very close runner up, and the development of new firmware may push it over the top. The T2i has the advantage of being even less expensive and produces identical video to the 7D, but may not have the firmware available for professional use any time in the near future.  Some people also prefer the fact that it uses SD cards instead of Compact Flash, as they tend to be less expensive and can be locked.

I’ll update this post as more information becomes available, and as I have time to absorb it. Please feel free to submit additional questions, comments, corrections and updates!

Which 70-200 Lens Should I Buy? A Quick Guide

Canon's 70-200 lenses, and a Sigma thrown in for good measure. Not to scale.

With the release of Canon’s latest offering, the EF 70-200 f2.8 USM IS II, Canon has at least 5 pro-quality lenses in the same focal length range. If you include the original EF 80-200 f2.8 from the 1990s (now discontinued, but still available used), the count is up to 6. And then there are the offerings from Sigma, Tamron, Tokina, and the other third parties. Tokina’s lens in this range, now over 8 years old, has fallen out of favor, and I’ll leave it out of this comparison. Tamron’s offering is very impressive optically, but does not currently have image stabilization. Sigma has recently announced the addition of a new, image stabilized version of their very popular lens (and we can hope for some minor improvements to image quality that is already very good).

As expected, with the differences in features, the prices run the gamut, from a very reasonable $700 to a very hefty $2500. The chart below should cover many of the details.

The MTF 50 numbers provided are all from independent tests (photozone.de) on similar equipment. I’ve refrained from providing MTF data for the other lenses (which are not currently tested at photozone.de) because MTF numbers are notoriously poor comparatives when testing conditions are not identical. Keep in mind that in each case, higher numbers are better, and the somewhat arbitrary cutoff point between the attribution of “excellent” and “very good” is 1850.

For what it’s worth, tests on the latest Canon lens (the mark II) have produced very impressive results. In addition to the improved IS, the image quality is now remarkably high; so high, in fact, that DPreviews give it a “best in class”, as it outperforms even the latest comparable Nikon lens.

How to Decide?

Determinations on what to buy will most likely come down to three factors. The most important is probably subject matter, followed by output type, and finally, your budget!

All of these lenses are designed for use in low light situations, with either a large maximum aperture, image stabilization, or both. Additionally, all of these lenses are designed for full-frame sensor cameras (such as the Canon 5D MarkII) but will also work on APS-C sensor cameras (like the Canon 7D, T2i, 50D, etc). With the APS-C models, you’ll benefit from the sweet-spot effect and get the least vignetting and most consistent sharpness from center to edge.

You can choose a lens with a slightly smaller aperture (f4) but with IS :

• if you shoot in low light but photograph subjects that are not fast moving. An image stabilized f4 lens will give you the equivalent of 3 times more light (3 f-stops) in a situation for hand-holding, but since your shutter speeds will still be slower you won’t have action stopping power.  If an f2.8 lens were shooting at 1/250th of a second, an f4 would need to shoot at 1/125th. A non-IS 200mm lens should not be hand held below 1/250th sec, whereas an IS lens can safely be held at 1/30th in many cases.
• if you primarily shoot scenics, architecture, etc, or shoot tripod mounted. If you use a tripod, then the matter of image stabilization is moot, and the aperture is much less important.
• if you don’t shoot in low light. Canon’s f4 IS lens has amazing resolution and is relatively inexpensive, so unless you need the single extra f-stop, it’s a great choice.

You can buy a non-image stabilized lens :

• if you primarily shoot from a tripod or monopod, or need to stop action. Sports photographers and wildlife photographers will not benefit as much from image stabilization because they’re required to shoot at high shutter speeds to stop the action, which already reduces the need for IS. Although IS does help sometimes, it can also sometimes make small adjustments in composition slow or otherwise awkward, too.
• if you shoot with flash, or in bright light. If you shoot with flash but want to keep bright lights/windows etc in the background sharp, IS can be handy, though.

You should buy an f2.8 image stabilized lens :

• if you can afford it. They are the most expensive, but give you the most flexibility.
• if you frequently shoot in low light, especially with high ISO, and with relatively slow moving subjects. News and Wedding photography really require this type of flexibility, unless you’re a heavy flash user/strobist.

WHAT DO YOU THINK?

What have your experiences been with these lenses? Although I’ve used most of them, I have not tested many of them thoroughly. I’d be interested to hear your stories and recommendations!

Who will benefit from paying for the Canon 7D?

[If you're interested in the VIDEO features of the Canon 5D Mark II, 7D, and T2i / 550D, you may also find this article helpful: Canon SLRs for Video - JMG]

This week’s introduction of the new Canon 550D / Rebel T2i raises some interesting questions.  This is a camera that clearly out-classes the Canon 50D in many regards, and has many of the features of the Canon EOS 7D, but at less than half the price (Currently $799 at Amazon.com). Will professional or semi-professional photographers be satisfied using the T2i instead of the 7D? What types of photographers will get any practical benefit from paying double for the Canon 7D?

Let’s get this out of the way first. If you’re at least a semi-pro, you’ll want to opt for the 550D designation over the “Rebel”, if it’s available. What photographer over the age of 15 wants a camera with “Rebel” in red letters across the front? Just kidding.

More seriously, though, let me do a quick side-by-side comparison of their features. If you’d like to see the whole table at once, just click use the drop-down menu at the top-left of the table:

The back of the Canon T2i is dominated by the 3" LCD

If you think any items should be added to this table for comparison, let me know.

There are certainly some differences between these cameras. The 7D has a metal body and a brighter viewfinder with full coverage. The 7D will feel better in your hand,  and these things are always nice. On the other hand, the new 550D sports a higher resolution LCD than the 7D, which can be handy in the field.

The main differences, though, are centered around a very specific style of photography, and really might not be a benefit to many photographers. The main area difference? Speed. The Canon EOS 7D will focus on faster moving subjects, and take more photos at faster shutter speeds. It has a faster flash sync speed, too. Many of these are the result of the dual-processor power of the 7D, though some are certainly limitations for marketing purposes… (my Canon EOS A2 in 1994 had a 1/8000th sec. shutter speed at half the price of this camera… I’m sure this isn’t a technological based limitation for the “Rebel”. I don’t remember ever using it then, either).

For example, if you primarily shoot in the studio, there would be no benefit to spending the extra $900 on the 7D, especially for product photography. Since they use the same sensor, the image quality will be identical. Fast moving models might be a little more of an issue if you’re shooting with very dim modeling lights, but most models are staying within a relatively small studio space, so this just wouldn’t make much difference. In fact, a great deal of portraiture work would fall under this category as well.

Similarly, if you primarily shoot landscapes or other still-life fine art photography, you can expect the same image quality as that produced by the 7D, and being able to focus faster and take 8 frames per second won’t make any difference.  Both have mirror lock-up, which is more important to this type of work. Indeed, if you’re backpacking and every ounce counts, the Rebel T2i / 550D has the benefit of being lighter. Keep in mind that if you’re rough on your cameras out there in the wild, the 7D will hold up better.

I suspect that the lens mount is the only metal portion of the housing of the Canon Rebel T2i / 550D

On the other hand, journalists who need to catch fast action on a regular basis will have better success with the 7D, as it has a superior auto-focus system. The Rebel T2i’s AF system is basically the same that found in the 40D, so if you have used that camera with success, the Rebel may suit your needs as well. Sports photographers will undoubtedly enjoy the accuracy of focus provided by the 7D.

Similarly, wedding photographers (especially wedding photojournalists) may find the speed and accuracy of the AF (as well as the other high-speed functions) useful for catching those moments that only happen once. If you’re a more traditional wedding portraitist, the 550D may suffice, especially as a backup. Indeed, you could buy two of the Rebels for the price of a 7D. David Ziser, a well known Ohio wedding Photographer (see his training videos on KelbyTraining.com) used a 40D for years. Personally, I would not use a 550D as my main camera for shooting weddings since my own work involves catching fleeting moments… but I’d consider using one for a backup or second body.

Needless to say, if you have the extra money, the Canon EOS 7D is going to be the superior camera. However,  that saved $900 could buy a pretty nice lens (or two) or some pocket wizards or flashes… The choice in the end depends on your shooting style and how important it is to have extra money left over for extras.

As always, comments are welcome!

READY TO BUY ONE? I’ve found that the best prices are at Amazon, but some people prefer B&H for their selection and reputation.

Introduction

Noise Reduction software is now an integral part of the photographic workflow, just as much as yellow and magenta filters were in the days of the wet B&W darkroom. They are particularly important, though, for those of us working in photojournalism, wedding photography, and similar fields that require us to shoot indoors in poorly lit venues at high ISOs. Even images from the best modern sensors benefit from proper noise reduction (NR) treatment.

One of Photoshop CS4′s few shortcomings, though, is its weak noise reduction functionality. To get the best results, it is now necessary to use 3^rd party software, either stand alone or as a Photoshop plug-in. Over the years, dozens of different NR programs have been released, but today, only a handful of them are really worthy of attention, either because of their popularity or effectiveness.

One wonderful site, MichaelAlmond.com, has already compared many of these programs, especially many of the older Photoshop actions, and I would not hesitate to recommend reading his information. I found, though, that his reviews were missing some key information and were, at the same time, not organized for quick reference. They’re also getting to be a little out of date (last updated in 2005). Consequently, I’ve decided to write some updated and augmented reviews of my own. I hope that you find them useful.

CLICK HERE TO GO TO THE MAIN ARTICLE INDEX

Screenshot of Noiseware in Photoshop CS4 on WinXP x64; click to enlarge.

Noise Ninja Screenshot, as a Photoshop Plugin on WinXP x64

Chapters: | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | Next |

Canon 7D vs Nikon D300s

A few weeks ago, I compared the Canon 7D to the Canon 5D Mark II, suggesting that they’re both excellent cameras, but suited to different types of work. However, there is another camera that appears to be intended for the same target market as the Canon 7D, with many similar functions and a very similar price (within $100). That camera is the Nikon D300s, which was released a few months before the 7D. Again, I can say that they’re both excellent cameras, and the deciding factor for purchasing one will undoubtedly be which of the features are most important to your photographic style.

But the cameras are not created equal. Let me begin with a side by side comparison of their most prominent features.

From this quick comparison, it should be clear that the cameras have a lot in common. The Canon 7D, however, seems to excel with its video functionality and it’s RAW shooting capabilities. As a RAW shooter, I must admit that I’ve have been very disappointed to find that I’d purchased a camera that claims 7 frames per second and can only manage 2.5. On the other hand, the D300s does have remarkably fast auto-focus, and slightly less shutter lag than the Canon.  If I were buying a camera based on its ability to shoot video, the added resolution of 1080p (as well as the ability to shoot slow-motion video at 60fps) would be persuasive, although I don’t have any particular interest in video.

Sensor and Digital Noise

Obviously, the Canon 7D has a substantially higher resolution sensor. With a fine lens (coupled with excellent technique), I have no doubt that the Canon‘s sensor will produce images superior to the D300s in good lighting situations. Many of us, unfortunately, spend most of our working day in poor lighting situations. The D300s, like it’s predecessor the D300, has excellent low light sensor performance.

Canon 7D: ISO 6400: 100% Crop

Canon 7D: ISO6400, Reduced to 12.3 Megapixel Equiv. (32%)

Noise reduction applied before reduction. (Noise Ninja, auto-profiled)

Let’s do a thought experiment. Suppose that the digital noise is significantly better on the D300s than the 7D (though I haven’t seen conclusive tests at this point). We know that digital noise is a pixel-level problem, and that the 7D‘s pixels are much smaller than those of the Nikon. If you were to take a noisy 18 megapixel image and down-sample it to 12.3, would any of that digital noise survive? What if you ran noise reduction on the Canon image before down-sampling? The downsampling would reduce the effect of the softening that is normally introduced by noise reduction. We are talking about a 32% reduction in size, which is significant.

The photos at left were taken with the 7D (pre-production) at ISO 6400, which is available as an extended ISO mode on the D300s, but is the highest normal shooting ISO on the 7D. Considering the grain that I used to get with Tmax 3200, even the noise of the non-reduced image is impressively well controlled, and once it is reduced, it’s not much of a problem in this case (although this example is less noisy than other parts of the image).

As you can see in the noise reduced example, because the noise reduction was applied before re-sampling, the sharpness of the final the two down-sized examples is very similar if not identical. This is the benefit of starting out with a much higher resolution image when post processing is going to be a significant factor. As far as I’m concerned, this final image is what the Nikon D300s has to compete with straight out of the camera (at its highest possible ISO setting). Unfortunately, I only have an older D300 available for testing at the moment, but since the sensor is the same, I may decide to post comparative photos later.

Canon 7D : ISO 6400, 100% Crop

Down-Sampled 32% to match the size of the Nikon D300s sensor.

Noise reduction applied before down-sampling. (Noise Ninja, Auto-profiled)

Lets take a final look at another region of the same photo in which the noise was a little more prominent to begin with.

After simple down-sampling, the noise in this part of the image was heavy enough to remain somewhat prominent. With the addition of noise reduction beforehand, however, the sharpness of the image remains roughly the same and the noise is becomes a minor problem, in comparison, though it is certainly not gone.

I’ve presented the preceding information based on the assumption that the Nikon D300s is equal to or moderately superior to the Canon 7D when it comes to digital noise to begin with. At this point, however, testing seems to show just the opposite to be true. Nikon D300s shots at ISO3200 and 6400 from at least one test are hardly recognizable, much less usable. Click here for further details (opens in new window).

Testing of both cameras will continue, and problems with each will become more apparent. At the moment, though, I’m inclined to believe that the Canon holds the advantage in this competition.

* The prices listed are from B&H Photo, as they are a reputable but inexpensive store. Cheaper prices may exist elsewhere on the internet (and are frequently seen in the Google ads that appear in the right column of this blog), but if they’re too much lower and new models haven’t been released yet, consider the possibility that you’re looking at a scam.

The Canon 7D and 5D Mark II: Resolution Comparison

I’ve had a chance to make a cursory comparison between some full resolution photos taken by the new Canon 7D and a Canon 5D Mark II, and the results have not been exactly what I expected. Before I go on to describe the results, let me mention that the 7D in question is a pre-production model, and results may improve (where theoretically possible) by the time that they ship. I’d also like to thank Steve Eastwood at Modelmayhem for providing the images.

As I mentioned in my previous discussion of these two cameras, the overall pixel count difference is minimal in terms of final print size, but because the 5D Mark II has a full frame sensor, it has a much lower receptor density (about 156 receptors per millimeter) compared to the 7D (about 233). Even though it may seem that higher resolution on the sensor would lead to sharper photos, we should not expect this to be the case in practice because even our best lenses offer a lower resolution than the 7D sensor, and therefore the sensor’s extra resolution will not be capturing extra detail.

Figure A: Canon 7D - 100% Crop

Figure B : Canon 5D Mark II - 100% Crop, ISO 3200

If this concept is hard to grasp, consider this scenario: suppose that you have a fixed focal length lens (say, a 100mm) on your 5D and you set up an object on a table in your studio so that, with your camera on a tripod 10 feet away, it fills the whole frame.  Now suppose that you put the lens on a 7D and place the camera on the same tripod. Of course, the object won’t fill the frame any more, it will be cropped. In order to fill the frame the same way (or as close as possible), you’ll have to back up a few feet.  After backing up a few feet, you’re now using less of the image that would be produced by the lens on a full frame camera to create the same photo, which also means that you’re magnifying the lens’s flaws.

Figures A and B are from a little less than 1/4 of the distance across the frame horizontally. This means that on the full frame sensor of the 5D, this is getting near the edge of the frame, which we’d expect to be a bit less sharp. On the 7D, this is using a more central part of the lens, so any lack of sharpness is less likely to be related to optical problems with the lens.

As you can see, however, the 5D is still sharper, though not by a tremendous amount. The difference is most noticeable in the “www” text below the logo box. Since the two images were shot at 3200, noise is also a factor.

Digital Noise

Figures A and B display a significant amount of digital noise, but in each case, no more noise than a CCD equipped camera would have produced at ISO 800 a few years ago. The question, however, is whether there is a difference between the cameras. At ISO 3200, there is remarkably little difference. This is counter to my initial predictions, and counter to conventional thought that suggests that denser sensors produce more noise. I’d still give the edge to the 5D Mark II, but I wouldn’t consider it enough to be a deal breaker.

At ISO 6400, the difference is more pronounced. Sample images are below.

Figure D: Canon 5D MarkII at ISO 6400

Figure C: Canon 7D at ISO 6400

Which is right for you, the Canon 7D or the 5D MarkII?

The Differences That Matter

The first difference worth mentioning, of course, is the price tag…. about $900 difference, if the current prices listed are any indication (7D at about $1599 at B&H or Amazon and the 5D Mark II at about $2499 at B&H or Amazon). [Note: Canon is currently offering rebates on both] Since we’re looking at a couple of cameras that have the build quality for professional use, with magnesium alloy bodies, full HD video capabilities, top notch processors, and some of the most advanced CMOS sensors around, we can expect professional quality results from either camera. In fact, comparing the columns of features for the two cameras reveals that the vast majority of them are identical.  Something must justify the price difference, though.

Most obviously is the CMOS sensor difference, the 5Dii being a 21M pixel, full frame sensor, and the 7D being an APS-C size holding about 18Megapixels. The 7D has dual Digic4 processors, whereas the 5Dii has only one. Probably as a result of this, the new arrival boasts burst speeds about twice as fast as the 5D. There are many other minor differences (and perhaps a few significant ones), but I think that these are the most important to consider up front.

Pixels and Sensor Size

The practical difference between 18 and 21 Megapixels in terms of raw size is minimal.

If all other things were equal, the pixel count between the 7D and 5D Mark II would not be a significant factor in choosing one camera over the other. I’ve illustrated the file size difference (left) with images scaled to the dimensions of each camera’s output, but just by looking at the numbers we can get a pretty good idea of how things would stand. The difference is about an inch in on each axis… not a big deal.

But of course, it’s not quite that simple. Since the 7D’s sensor is considerably smaller than that of the 5D, its receptors are also smaller and more densely packed. Traditionally, dense receptors have produced more digital noise than their larger counterparts, especially during long exposures which generate more heat. Canon has done a good job of controlling digital noise with their efficient sensors and processing in the past, and although the 7D produces relatively little digital noise, it still falls a bit short of the performance of the 5D Mark II, which has been so highly praised for its ability to produce low noise images in nearly any lighting situation. A variety of ISO comparisons are available across the internet, including mine, here, if you’d like to see how subtle the difference is.

Much more importantly, though, is how the sensor size effects resolution. Many photographers have already noted that the receptor density of the Canon 50D has already matched (in resolution) what we used to achieve with slow 35mm film. Indeed, on the 50D, the sensor density is roughly 213 pixels per millimeter, a density that would produce a 39 megapixel image on full frame sensor such as the 5D series. The 7D takes this development even further, with around 233 pixels per millimeter, at which resolution a full frame sensor would produce a 46.7 megapixel image.

Why do these numbers  matter? Because at this resolution, the image quality is frequently limited by  the lens rather than the sensor.  Even at the 15 megapixels of the Canon 50D (and certainly at the 18 megapixels of the 7D) the sensor will usually have the resolution to capture all of the detail that the lens can resolve, including the flaws in the lens performance such as chromatic aberration, corner softness, diffraction, and any manufacturing flaws; adding additional megapixels will only serve to increase file size, not detail. The same thing can be achieved with good up-sampling software, such as onOne’s Genuine Fractals.  Furthermore, since the sensor is smaller than a full frame dSLR’s, the image will have to be enlarged proportionately more to achieve the same size print… which will also enlarge the flaws from the lens. An excellent article about this effect in the Canon 50D with photographic examples can be found on the Luminous Landscape.

In order to reap any benefit from the increased resolution of the 7D’s sensor, photographers will need to use the best lenses and their best technique. Some of Canon’s “L” lenses and a few lenses from the Pro lines of other manufacturers (such as Sigma, Tokina, and Tamron) will produce quality results, but even those lenses will need to be used properly. The photographer will need to determine the optimum aperture for each lens (at which it produces the highest resolution across the full frame) before being limited by diffraction by the aperture leaves. Furthermore, tripods and remote (or timed) release will be crucial.

Who Should Buy the Canon 7D, then?

From the previous section, you might be under the impression that I would not recommend the 7D, but that’s not the case. The issue depends entirely on the photographer’s shooting style. The speed of the 7D, coupled with its new AF system and large, bright viewfinder, make it an excellent choice for sports photographers and other journalists for whom the increased (1.6x) magnification are a benefit. Wedding photojournalists may be included in this group. These photographers, who regularly hand-hold their shots and reproduce them in forums that do not necessitate the highest resolution, are not effected by the lens resolution limits.

Art and Landscape photographers, on the other hand, may benefit from the better overall resolution of the 5D Mark II. Since these photographers typically shoot for the highest resolution, with heavy tripods and excellent technique, they will notice the better image quality from the 5D, but also will get the most out of a 7D if they happen to use one.

Video Features

If you’re interested in the video capabilities of the 5D Mark II and the 7D (and Rebel T2i), please follow this link to my recent article on the subject: Video Features of the Canon EOS 5D Mark II and Canon EOS 7D.

Please Comment! I’m always interested to hear whether my readers find the articles interesting, useless, or otherwise… and more importantly, I’d like to hear your opinions and additional information, even if it’s just  a tidbit. THANKS!