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Some M-Mount Field Curvatures

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I haven't posted very much lately. We've had some new equipment installed and we've been doing a LOT of testing as we develop our new database of lenses on the optical bench. As the database fills out I'll be posting more than ever, just because a lot of this stuff is just fun. Today's post is largely for fun, but will have some additional interest for those who shoot Leica or shoot M-mount lenses adapted to other cameras.

One thing that optical bench testing gives us that is hard to find elsewhere is a clear map of field curvature. We had a client interested in determining field curvatures for a several M-mount lenses and thought there would be a few among you who also wanted to see them. Continue reading

HandeVision IBELUX 40mm f/0.85

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Image credit Lensrentals.com

Preconceptions

I try to start these articles by putting my preconceptions out there first. Every reviewer or blogger has them, they affect our opinions, and you have a right to know them. So I'm writing this introduction the day before our first copies arrive.

The HandeVision IBELUX 40mm f/0.85 is designed by IB/E Optics GmbH in Germany and manufactured by Kipon (aka Shanghai Transvision Photographic Equipment Co. Ltd). IB/E has developed a number of lenses and adapters for the Cinema world and other optics, so I figured the design would be good; probably a telecentric lens with a built-in Speedbooster-type element or group. Kipon is known as a lens adapter company, although Shanghai Transvision has also manufactured and distributed video and photo accessories. They are rumored to manufacture lenses for other brand names, so they have some lens manufacturing experience.  But, I have to say, my expectations for build quality weren't great. I expected a lot of variation between copies. I don't know if I even had any expectations regarding image quality.

Okay, so much for what I expected. There are now five new copies sitting on my desk so let's take a look. Continue reading

A Useful Metabones EF to Black Magic Pocket Camera Article

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Way back in the old days, before everything was plug and play, you could buy a computer and accessories from one manufacturer and be certain it would all work together. The cool kids, though, would mix-and-match different pieces and end up with a better system that could do more things than any one manufacturer's system would, and for less money. They realized they might have to spend some time getting this to work with that, and once in a while things wouldn't work at all. That's the price you pay for being a cool kid and getting more for less money.

The people who had problems bought the same thing the cool kids did, but just got irritated when things didn't all work together right out of the box. The cool kids laughed, felt even cooler, and made some money debugging the other kids' systems for them.

We do the same thing today with cameras. It's simple to use a rig, lenses, monitors, whatever of the same brand. It will probably cost a little more and you may have a few less capabilities, but it's just about guaranteed everything will work fine with everything else. But if you want to save some money and expand your capabilities, you mix-and-match systems, often using an adapter or two.  The problems come when people don't realize that not everything is going to play nice with everything else. The problem is compounded because the people who make the widgets just don't have the capabilities of testing everything with everything else.

A few weeks ago Metabones sent me one of their new EF lens to Black Magic Pocket Camera Speedboosters to play with. I did the usual optical testing and let some of the video guys shoot with it, like all the other bloggers do. I planned on writing a piece saying how awesome the optics were (they are) and how many cool things it lets you do with a Pocket Camera (it does) like all the other bloggers do. But in our testing we found a few things that didn't work well together, and it occurred to me that rather than adding yet another "The EF to Pocket Camera Speedbooster is Really Great" blog post, I could do something useful and actually list what it works well with and what it doesn't.

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Of Course We Took One Apart

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A Look Inside the Canon 16-35 f/4 IS

This is a Geek Article. Many of you don't understand the term 'Geek' properly, so perhaps this will help. As the graph shows, if you aren't both intelligent and obsessed with photo gear, you won't enjoy this article. 

I've tried hard to find whom to credit for this, but haven't been able to. If you know, please let me know so I can credit this brilliant work.

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Canon Wide-Angle Zoom Comparison

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Left to right: Canon 16-35 f/2.8 II, 16-35 f/4 IS, 17-40 f/4. Can you spot the one with the wrong hood? The intern obviously couldn't. 

 

As is so often the case, I bit off more than I wanted to chew when I came back from vacation. The Canon 16-35mm f/4 IS lens had just been released, a few copies were in stock, and I thought I'd do a nice quick test. But one of the reasons I'd wanted an optical bench was because I don't trust Imatest results with wide-angle lenses. At 16mm, even with the very largest test charts, we're testing at about 4 feet shooting distance.

So I after I did our standard Imatest on the 16-35 f/4 IS, I wanted to repeat the results on our optical bench. Of course, I don't have a big database of optical bench results to compare against like I do with Imatest. So I had to do optical bench tests on some other wide zooms for comparison purposes. Then I had to do some more comparison with other lenses to see if the variations we were seeing on the optical bench were simply a new, higher resolution testing method, or if they were telling me something about variation with wide-angle zoom lenses. (Both things were true.) Anyway, the testing I thought would take a week has taken three.

I realize some of you just want to see the usual Imatest results on a group of these lenses since that's what you're used to seeing. Others are also interested in the optical bench results showing how the lenses resolve at infinity, rather than just close up. And of course there are a few of you who want all the gory details of Geekiness that the optical bench reveals. So I'll try to present this in three parts: the Imatest results first, the optical bench optical test results second, and the geeky stuff third. It's a buffet; just grab what appeals to you.

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Save 15% This Summer

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Get 15% off this summer when you reserve your order a week in advance. Just place your order at least 7 days in advance of the arrival date and save!

Enter the code SUMMER15 during checkout and get 15% off on your order.

  • Order must be placed 7 days in advance
  • Eligible arrival dates: 7/28/14 - 8/29/14
  • May not be combined with other offers

A New Old Lens

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Like a lot of photo history buffs, I've been quite excited about Lomography's new iteration of the Petzval lens in 85mm focal length. For those of you who don't know about the Petzval lens, I wrote about it a few years ago. It really has a rather a fascinating story.

Since writing that article, I've been rather obsessed by this lens. I own several of them, made in the late 1800s, but I haven't been able to adapt them to work on a modern camera. Now Lomography has reproduced the Petzval lens in a nice brass housing, for either Canon or Nikon mounts. Our first copies arrived yesterday and I grabbed them for a bit before they headed out the door.

The new Petzval is quite a handsome bit of kit.

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Sensor Stack Thickness Part III: The Summary

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Well, I have to admit this has been a fun series. I've learned a whole lot. That's what makes this so fun -- I get some results I don't understand, get some help figuring out what is going on, and before I know it, I've learned something that explains other things I haven't been able to understand.

In the second part of this series, we started a database of sensor stack thickness and exit pupil distances, hoping that it would help people decide which lenses would adapt best to which cameras. (And, of course, determine which lenses would not adapt well to which cameras.) A number of people have added information to the database since it was first posted -- enough to make it pretty useful.

Since the database is now large enough to be useful, I thought it would be a good idea to make a summary of what we know about lenses and sensor stacks. The best thing about all this, for me at least, is that it lets us make some generalizations about which lenses would be expected to have problems on which cameras.

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Some Holiday Lens Mutilation

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A couple of weeks ago I got an email asking if we would be willing to take some lenses, remove the electronics, fix the aperture wide-open, and permanently lock them at infinity focus. It seems the person who needed this done was having trouble finding a legitimate repair shop or service center that was willing to do it.

Well, illegitimate is our specialty, so I started negotiations about just how exorbitant a fee we would charge for this work. We quickly arrived at a fair price (no money, but we get to take pictures) and yesterday received brand new copies of the Canon 100mm f/2 and Sigma 35mm f/1.4 Art to work on. If you're the kind of person who slows down to view car wrecks or spent $200 on fireworks for the 4th of July holiday, you might like this.

(For those of you who aren't American, the 4th of July is when we celebrate our Independence by getting sunburned, making burnt offerings of animal parts in our backyards, and then eating said offerings. During the entire day, we drink massive quantities of American beer and once it gets dark we shoot off massive quantities of Chinese fireworks. All too often, the results of mixing alcohol and explosives prove that Darwin was correct -- but hey, that's what celebrating is all about, right?)

If torn apart camera lenses make you squeamish, then you won't like this, and I suggest you not read further. You won't miss learning anything; it's just for fun. As best I can determine, this post has absolutely no practical use whatsoever. It's just something to amuse and entertain those of you who are amused and entertained by such things.

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Save 15% for July 4th

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Get your July 4th weekend order early, and save 15%. Just set your order to arrive on Monday, June 30th, or Tuesday, July 1st, and get 15% off your total rental fees!

To take advantage, just use the JULY4TH promo code. Already have an order for July 4th weekend? Simply call or email us to change the order to arrive on an eligible date, and apply the discount code.