More Canon 400m DO II Comparisons

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In an earlier post we were most impressed with how much better the new Canon 400mm f/4 IS DO II resolved compared to the original version. I mentioned that we hadn't been able to get many copies and didn't have time to do any other comparisons right then, but that we would do more as soon as we could.

We still haven't gotten many copies, but we did get a little time, so I did the two comparisons that had been most requested: the 400mm DO II against Canon's 400mm f/5.6 L and against the Canon 300mm f/2.8 IS II with 1.4x TC III.

We still haven't received any of the other couple of dozen 400mm DO IS II lenses we've ordered, so the results are for the same pair as the original post. For all other lenses in this post we tested four copies and averaged the results. For the 300mm f/2.8 with 1.4X TC III test we used four lenses and four different converters. All tests are done using the same backlit film chart as the previous test, using a Canon 5D Mk III test camera.

400mm DO II vs. 300mm f/2.8 IS II

The first comparison we made was between the 400mm f/4 DO IS II and the 300mm f/2.8 IS II at their native focal lengths - 400mm and 300mm. I do want to point out that this puts testing distances at roughly 19 and 15 feet respectively. This is not ideal working distance for super telephoto lenses, so take these results with that tiny grain of salt.

We tested the 300mm lens at both f/2.8 and at f/4 to level the playing field a bit.

400mm f/4 DO II 300mm f/28 IS II f/2.8 300mm f/2.8 IS II f/4
Avg Corner110011001160

These results are about what I expected, since we already knew that the 400 DO II is really excellent. Shot at its native f/4 it has a bit better resolution than the 300 f/2.8 does shot at f/2.8. Stop the 300mm lens down to f/4, though, and it's a bit sharper than the DO.

Could you notice these differences in a photograph? Probably if technique was equal and you pixel peep a bit. But these are all spectacular results. If you can't tell the difference between a 300mm f/2.8 shot at f/2.8 and at f/4 (most of us can comparing side-by-side shots), then you sure can't tell the difference between either one and the DO.

400mm Comparisons

The question most people (and by most people, I mean me and a couple of others) wanted answered was how the 400 DO compares to the 300 f/2.8 with a 1.4 X teleconverter added. Other people wanted to know how it compares with the tried-and-true, bargain-priced Canon 400mm f/5.6 L, so we did those comparisons too.

Let's again point out that there are some differences in these tests. The 300mm f/2.8 with teleconverter is actually shooting at 420mm, so it gives a bit more reach. The 400mm f/5.6 is being compared one stop down compared to the other two, which are being shot at f/4, which gives it a bit of an optical advantage.

400mm f/4 DO II 300mm f/2.8 with 1.4X 400mm f/5.6 L
Avg Corner11001080990

The results, again, are fairly triumphant for the DO. The DO version I, which I shot with frequently, definitely gave up some image quality compared to a 300 f/2.8 with teleconverter. Most of us who shot the DO were willing to do so because it weighed less, and the weight was distributed near to the mount making it easier to handhold. The version II 300 f/2.8 is much lighter than its predecessor, so the weight savings isn't quite as significant. However, it's clear that from a resolution standpoint at least, the 400 DO is slightly better than the 300 f/2.8 IS II with teleconverter.

Again, let's remember that with DO lenses, field tests in varied lighting conditions may well reveal other issues that a simple resolution test can't. But the resolution test certainly suggests that shooting the DO could give results at least as good, and perhaps a tiny bit better, than the 300 f/2.8 IS II with teleconverter.

The results with the 400mm f/5.6 weren't surprising to me at all. It has always been regarded as a very sharp lens. Given that it's shooting at a 1-stop narrower aperture, no one should be shocked that it can hang with the other two lenses in the center. The price is certainly far more attractive, although the narrower aperture and lack of image stabilization make it a very different lens than the other two.

Would I sell my 300 f/2.8 IS II and move to the 400 DO? I doubt it. But if I was considering the two for purchase and realized I was going to shoot at 400mm, I'd be leaning towards the DO. It's still easier to shoot handheld, the IS systems are now equal, and it doesn't appear to give up anything from a resolution standpoint.

Can I get equivalent shots with a 400 f/5.6? If the light and technique are good, I can certainly get very close, if not equal shots. But the other two lenses will get shots in a lot of conditions that the 400 f/5.6 could not shoot well in.


Roger Cicala and Aaron Closz


January 2015



Cotton. Sidney Cotton.

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"He caused a lot of trouble over here, you know."  A librarian at the Royal Aeronautical Society, when asked for references on Sydney Cotton.

It's been a while since I did a history article. I love writing about the true "characters" of photography, and to be honest, I hadn't stumbled across anyone that really interested me for a while. But while I was writing an article about the most decorated photoreconnaissance flight in history, I kept running across the name Sydney Cotton, who was considered the father of aerial reconnaissance. Continue reading

A Thinner Sensor Stack

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A few months ago, before my hiatus from blogging, we did a series of articles showing the effect that a thick sensor stack (the glass above the sensor) had when we use adapted lenses designed for a thin sensor stack. The first one was mostly about theory, the second about when it was likely to actually be noticeable, and the third gave a general summary of when you might expect problems. All of that theory and prediction is good and useful.

The articles generated a fair amount of discussion about removing filter stacks on cameras so that they would perform better with legacy or film lenses designed for little or no sensor stack. In theory, that would make a big difference, but changing the stack has its own set of issues: focus is changed, infrared filtering can become inadequate, etc. Recently, though, our friends at Kolarivision, who had contributed a lot to our database on filter stack thickness, asked us to do some independent resolution testing for them.

They had modified some Sony a7R cameras, removing most of the thick sensor stack and replacing it with thinner Schott BG39 glass (I do not know the exact thickness of the replacement glass, but it is described as 'significantly thinner'). The replacement glass closely matched the original IR transmission, maintaining accurate colors, but, in theory at least, should improve resolution on wide-angle, wide-aperture, short-backfocus distance lenses. In other words, it should improve the performance of the a7R using wide-angle Leica and other M-mount lenses designed for film.   Continue reading

A Brief 400mm Comparison

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Canon shooters have a bit of 400mm excitement right now. The biggest news, of course, is the release of the 100-400mm f/4.5-5.6 IS II lens, replacing the original version that's had a very long, successful run. Not quite so much excitement was generated by the release of the 400mm f/4 DO IS II lens. It too replaces a long running lens, but one that has been considered more of a niche lens. (I'll admit, though, it's been one of my favorite niches. I used the 400 DO a lot over the years.)

Most surprisingly, neither lens was released at a huge price increase. The new DO II lists for $6900, compared to $6470 for the original version. The new 100-400 IS lists at $2200 compared to $1700 for the original. Both new versions promise several improvements to the older versions, but we were most interested in how good the optics might be. So, of course, we ran these through Imatest at 400mm the day they came in.

One thing I need everyone to be aware of: We tested these on the new, high-resolution film-transparency, backlit Imatest targets. These are particularly good for testing high-resolution telephoto lenses, but do give us higher resolution numbers than the larger, printed charts we use for more general testing. So, while you can compare the results of these four lenses today against each other, you can't compare them to some older Imatest numbers for, say, the 70-200 f/2.8 lens and draw any reasonable conclusions.

We're simply evaluating them today to see if the newer optics provide a higher resolution than the older ones. Of course, we expect them to, but it's still worth checking. The original versions of both lenses were pretty darn good.

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Christmas Special - Save 25% on Rentals

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Do your holiday plans or New Year's resolutions involve photography?  If you've been excitedly waiting to use a certain piece of gear, now is the best time to try something for the first time.  Use promo code HOLIDAYS to save 25% off any rental this season from December 23rd to January 2nd.

  • Orders must have a delivery date between 12/23/14-1/2/15
  • Can not be combined with any other offers
  • Limit- 2 rental orders per person

One, Single Samsung NX-1 Test

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I just want to be clear, before we get started, this is not an NX-1 review. It's not even a complete optical test. It's simply me answering a single question: is this new Samsung worth further investigation from an optics/image quality standpoint?

Samsung's 28.2 megapixel, APS-C backlit sensor should capture more light with less noise, with a bit higher resolution than the 24 megapixel sensors in the competition. The hybrid AF system with striped illuminator should be quick and accurate. The short lag time 2.36 mpix OLED, low-lag-time EVF should be great. I know the built-in WiFi will actually be useful, because I've used lesser Samsung cameras in the past just for that feature.

All of those things are well and good. But none of them are even worth investigating until one simple question is answered: is this camera system (meaing camera and lenses) competitive with other APS-C cameras I can buy? Because I've sung the "Baby, I Love Your Sensor, but you Just Ain't Got No Optics Blues" to too many cameras already. Continue reading

Get 5% Back On Keeper Purchases

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Looking to buy some gear this holiday season but not sure what? Try it, then buy it with Lensrentals Keeper. During the holiday season, we're adding an extra bonus! Get 5% of your Keeper purchase price back as a rental credit, good towards a future rental.

The Details

  • Any Keeper purchase from 12/1/14 - 1/31/15 is eligible
  • 5% of purchase price, net of sales tax
  • Rental credit will be applied to purchaser's account on 2/1/15

Black Friday Sale

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It's time for our 5th annual Black Friday Sale! The sale begins at 8:30 AM CT on Wednesday.  At our sister site, LensAuthority.com, we'll be giving you 10% off all used equipment. We'll also be having special deals throughout the sale, so keep your eyes peeled on the Special Deals section and be sure to follow LensAuthority on Facebook and Twitter to get announcements of any special deals during the sale period.

Over at Lensrentals.com, we're giving you are best discounts of the entire year! Place an order for any arrival date before April 1st, 2015, and get 25% off using the promo code BLACKFRIDAY. Been longing to try a certain lens? This is the perfect time to take it for a test drive (and don't forget about our Keeper program when you fall in love with it).

The Details

  • 25% off any rental placed at Lensrentals.com using the code BLACKFRIDAY
  • Order must be placed between 8:30 AM CT on 11/26/14 and 11:59 PM CT on 12/1/14
  • Eligible for any rental with an arrival date before 4/1/15
  • Limit - 2 rental orders per person
  • Not combinable with any other promotions or coupons

Cracking Open the 7D II

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OK, I have to admit I really like the 7D Mark II. I didn't want to because it wasn't what I wanted. I wanted to see the new Canon chip foundry that would be cranking out high-resolution sensors. But despite wanting to hate the 22-megapixel APS-C camera, after a fairly short exposure to the autofocus system, I have to admit I like it. There's just something about getting every shot in focus every time that's appealing to me.

However, when I read that Canon claimed the 7D II has "4 times better weather sealing than the original 7D" I went mildly nuts. Most of you know I hate marketing drivel. HATE IT. Most of you know I'm generally not impressed with weather sealing claims. Unless something has changed in the last 30 seconds, weather sealing still means, "the warranty doesn't cover water damage."

So when I read the claim "4 times more weather sealing" my inner cynic just thought 4 times zero equals zero. But I wanted to be fair so I decided I'd open up the 7D II before I wrote a scathing article about making ridiculous weather sealing claims. Which results in me once again writing an article where I have to admit my assumptions were wrong less correct than I would have liked. (Sorry, I forgot for a moment this was the internet where no one ever says "I was wrong.")


The 7D and 7D Mk II looking awfully similar in front view.


For those who want to take my word for it and skip on to some other blog, the Canon 7D Mk II may be the best weather-sealed camera I've run across. It's excellent. For those who would rather see for themselves, gory camera dissection pictures follow!!

I'll add, because someone always wants to comment about the poor quality of my dissection photos, that you're welcome to try shooting with one hand while taking two cameras apart with the other hand under 4 tungsten hot-lights, making sure you have the camera back together by the end of your lunch break. We don't do high-quality product photos back in the repair department. But better this way than if we let the product photo people try to take the cameras apart.

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About That 25-300mm f/2.8 You Wanted

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I get an email or text about once a month asking me if I think Canon, Nikon, or some other photo manufacturer will ever make something like a 24-300mm f/2.8 zoom lens. I'm usually gentle with those people, because I realize that a lot of people truly believe that if they want something badly enough, someone could make it for them. Occasionally, someone exhibits the Dunning-Kruger Effect and tells me that they know it's a plot on the part of the manufacturers to make us buy multiple lenses instead of just one that could do everything.

I had another one of those emails a few days ago, so I thought it might be interesting to show everyone what a 25-300mm f/2.8 would (approximately) look like. We don't actually have a photo lens of that specification, but our video friends do: The Fujinon 25-300mm T3.5. (For those who don't know, f is a calculated value, T is actual light transmission. Most f/2.8 lenses are T3.5 to T3.8.)

The Fujinon is a PL mount lens, so I'm afraid you won't be able to adapt it to your 5DIII or D810. If you really want to, though, you could buy a PL modified Canon 7D camera and use this as your walk-around lens.

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