Sassan Sanei, The Blog of
A random selection of musings and ramblings.
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Perspective control with the new Canon TS-E 24mm f/3.5L II tilt/shift lens
Have you ever found yourself pointing your camera upward to take a picture of a tall building?

If so, chances are that your picture turned out something like the one below, which I made using a 24mm wide-angle lens on a Canon EOS 5D Mark II full-frame camera body:

Picture with 24mm lens, camera pointed upward
24mm lens pointed upward


See how all the vertical lines converge upward, even though they are parallel in real life? The building seems slanted, like it is about to topple over. This might be fine for the Leaning Tower of Pisa, but it makes for a very strange picture of an office building!

You can get rid of the bizarre angles by pointing your camera straight ahead, perfectly perpendicular to the building. This eliminates the converging lines. Unfortunately, this also causes you to lose the top of the tall building, as you can see in the next picture:

Picture with 24mm lens, camera pointed straight ahead
24mm lens pointed straight ahead


The obvious solution is to use an even wider lens. This is often an elegant solution to the problem, as long as you have an interesting foreground to work with, and don't mind the building becoming a background element instead of the principal subject of the image. The lens must also be wide enough to take in the top of the building.

The following picture is an example of what not to do. None of those three criteria are met in the following picture. The foreground is vast and boring, the buildings have been relegated to the background, and the top of the tall building is still cut off (although just barely). This is taken with a Canon EF 14mm f/2.8L II USM lens on a Canon EOS 5D Mark II full-frame camera:

Picture with 14mm lens, camera pointed straight ahead
14mm lens pointed straight ahead


Admittedly, I could have changed my location to make that picture work better, but I really just wanted a picture of the building and its immediate surroundings.

Is there a way to take a decent picture of tall buildings? There must be; after all, professional architectural photographers do it all the time. What technique do they use to control perspective?

The answer lies in the magic and wonder of... the tilt/shift lens.

Actually, there is nothing mysterious or exotic about this lens. Photographers have been tilting and shifting lenses on large-format cameras for well over a century. These days, the soaring popularity of digital cameras -- and the ability to quickly "fix" mistakes in Photoshop -- has created an expectation of convenience and instant results. Tilt/shift lenses are considered a specialty item; it takes skill and patience to use lens movements effectively, and many think that it is becoming a dying art.

Using a shift lens, it is possible to point your camera straight ahead, then move the lens upward until your image includes the top of the building. Since the lens is no longer centred on the camera, the image is off-centre too. You take in the top of the building, while vertical lines remain parallel since the camera is not tipped upward. The following picture shows how this works. This image is straight out of the camera -- no Photoshop needed. It's a perfect solution!

Pictured with 24mm lens, shifted up 11mm, camera pointed straight ahead
24mm tilt/shift lens shifted upward by 11mm


This picture was made with the new Canon TS-E 24mm f/3.5L II lens. I already had the original version of this lens, but the improvements in the new version are well worth the upgrade. The new lens completely eliminates chromatic aberration (colour fringing), which was a problem with the original version. I also like the ability to change the direction of tilt relative to the direction of shift -- with the original version of this lens, I had to take the lens apart, turn half of it around, and put it back together. There are several other worthwhile improvements as well.

Unfortunately, the lens is manual focus only; like all tilt/shift lenses, it does not have an autofocus motor in it. The Live View mode with 10X magnification on my Canon EOS 5D Mark II camera makes manual focusing much easier than using the viewfinder.

Keep in mind that I am using the 24mm lens on a full-frame camera. Canon has also launched a new TS-E 17mm f/4 tilt/shift lens, which provides a wide angle of view on a crop-sensor camera like the Digital Rebel series or the EOS D30/D60/10D/20D/30D/40D/50D. Of course, either lens can be used with any Canon EOS camera, depending on your needs.

Perhaps the biggest drawback to tilt/shift lenses is their price. In Canada, Vistek has the best deal going right now, offering the 24mm lens at $2399 and the 17mm lens at $2699. This is slightly lower than U.S. prices, even at the current exchange rate, but it is still a lot of cash to fork over.

Fortunately, there are a couple of ways to eliminate converging lines without buying an expensive shift lens.

The first method is to take a wide-angle picture and crop it off-centre. Take a look again at the image from the 14mm lens, below, and compare the cropped area to the shift lens picture above. They are exactly the same. The difference is that you lose a lot of resolution. The original image is 21 megapixels, while the cropped area is only 7.2 megapixels. This represents a huge loss of detail.

Picture showing an image from a 14mm lens cropped to resemble an image from a 24mm shift lens pointed straight ahead
14mm lens pointed straight ahead, then cropped off-centre to resemble a shift lens


The second method is to take a picture with your camera pointing upward, then correct the perspective in post-processing. In the past, when I used a darkroom to make prints, I would tilt the enlarger base to do this. Today, perspective correction is much more easily done using Photoshop!

Picture showing an image from a 24mm lens pointed upward, stretched to resemble an image from a 24mm shift lens pointed straight ahead
24mm lens pointed upward, with perspective later corrected in Photoshop


This method actually produces surprisingly good results, and the stretching process does not cause any noticeable loss of image quality. In fact, vignetting (darkening of the corners in the sky) is improved. The only drawback is that the lower corners of the image are cut off, so you must anticipate this when you initially compose the image.

This presents an unusual dilemma: buy the Canon TS-E 24mm f/3.5L II tilt/shift lens and correct perspective distortions at the time of image capture, or the Canon EF 24mm f/1.4L II lens and correct perspective distortions in Photoshop? The latter costs less, has autofocus, and has a much faster aperture, which makes it more useful in most situations. Therefore, I would not expect most photographers to choose the tilt/shift lens over the f/1.4 lens unless they have a specific need for lens movements.

Incidentally, you might be wondering why buy a 24mm lens at all if you already have a zoom lens that covers that focal length. The difference is in the image quality. Unfortunately, the 24mm setting on my Canon EF 24-105mm f/4L zoom lens suffers from chromatic aberration and barrel distortion. While it is useful for everyday photography, I do not find it acceptable for architectural photography.

The Canon TS-E 24mm f/3.5L II lens also offers a tilt mechanism, which is completely separate from shift. Tilting means changing the plane of focus so that near objects on one side of the image are in focus, while far objects on the other side of the image are in focus. The rest of the image is blurry. This is used to follow focus along a slanted line, like railway tracks receding into the distance, or a clump of flowers in the foreground against a treetop in the background. It can also lead to some very creative and unusual effects.

In the following image, I tilted the lens to the left until only the front face of the tall building was in focus, while the rest of the image went to blur. This has the effect of drawing the eye to the office tower, making it the dominant subject in the picture, even though it is in the background. Notice how some of the trees are also in focus; this is because they happen to fall along the tilted plane of focus. This picture uses both shift and tilt together to bring a fresh look to a fairly ordinary picture.

Picture showing selective focus achieved through use of tilt
24mm lens shifted 11mm upward and tilted 8.5°left


Here is another image in which I tilted the lens downward. This allows the tree to become blurry at the top. (Unfortunately, this effect is lost on a small image on the web, but it is readily apparent on a print.) I did this because the image is about the contrast between the gnarled roots of the maple tree and the hard angles of the building. The top of the tree provides only context, and I did not want it competing with the building for the viewer's attention. Without tilt, I would simply have a picture of a sharp tree against a blurry building, which would draw attention to the tree instead of the juxtaposition of forms. This is one of the first images I made with the new lens.

Maple tree roots exposed against the Photovoltaic Research Centre, at the University of Waterloo.


Here are a few more images that I made while getting acquainted with this new lens:

Maple tree roots exposed against the Photovoltaic Research Centre, at the University of Waterloo. Cluster of trees and shrubs with the Dana Porter Library visible in the background, at the University of Waterloo. Mountain bluets against the Dana Porter Library, at the University of Waterloo. Construction continues on the new Engineering V building, at the University of Waterloo. This pyramid of 700 barrels from the old Seagram distillery is visible in front of the Centre for International Governance Innovation (CIGI) in uptown Waterloo. These barrels will soon be removed to make way for the new Balsillie School of International Affairs. This steam train with cars and caboose, restored by the Southern Ontario Locomotive Restoration Society, runs seasonally between St. Jacbos and uptown Waterloo, stopping at the farmer's market along the way.


There are many other creative uses for this lens. You can use it to exaggerate perspective, selectively focus on one part of the image, and make dramatic environmental portraits.

Keep in mind that while wide angles are useful for architectural photography, Canon makes tilt/shift lenses in several focal lengths: 17mm, 24mm, 45mm, and 90mm. I frequently use the Canon TS-E 90mm f/2.8 tilt/shift lens for product photography -- a purpose for which the 24mm lens is far too wide. The 90mm lens is useful not so much for shifting, but for controlling the zone of focus through tilt.

Tilt/shift lenses are the ultimate tool for controlling every aspect of your photograph. The process is slower and more methodical than with other lenses, but that is well worth the sense of satisfaction you get from creating an image exactly your way.

The first set of images were made at the Sun Life Financial headquarters in Waterloo, Ontario, Canada. All the images are straight out of the camera without any adjustments. The last seven images were made at various locations in Waterloo, and have had local adjustments applied to colour, exposure, and dynamic range. All images, except the third, were made with the Canon TS-E 24mm f/3.5L II lens on a Canon EOS 5D Mark II camera. You can click on any picture to see a larger version in a new window.

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On June 14, 2009 9:49 AM, Blogger mark wrote:

hey sassan,

what's a decent quality entry level dslr you would recommend for a first time photographer?

markoos.
 
On June 15, 2009 1:33 PM, Blogger Sassan Sanei wrote:

There are lots of great DSLR's out there, so it mostly depends on which one you feel most comfortable using -- the controls are all laid out differently by manufacturer. Is there a photo store near you where you can try out different ones and see what you like? It depends on your price range too, and what kind of lens you want to start with.

I'm partial to Canon myself because that's what I use, and their Digital Rebel line of cameras are both reasonably priced and extremely versatile. They just launched the T1i which is their "latest and greatest" and captures video. If you don't need video capability, you can pick up last year's XSi model at a decent price.

The Canon EOS 50D and EOS 5D Mark II offer more advanced features and, in my opinion, a much better user interface, but they also cost quite a bit more. If your budget allows it, these are both excellent cameras. The 5D II in particular produces results that are far superior to 35 mm film; you will need to make sure you are using high-quality lenses to match its resolving power. But this is probably overkill if you are starting out, and the cost can run into many thousands of dollars.

If your interest is fine-art photography then a good starting point is a Canon Digital Rebel T1i or XSi, or Canon EOS 50D, with a Canon EF-S 17-55mm f/2.8 IS lens. I think that the lens is much more important than the camera, myself. The best thing to do is try them out and go with the one that feels right in your hands. Become one with the camera, grasshopper!
 
Canon EF 14mm f/2.8 L II USM lens - first pictures
While many photographers prefer shooting with telephoto lenses that get them closer to their subjects, I've always had a preference for wide-angle lenses that let me capture a vast expanse in a single frame.

I've enjoyed using panorama stitching software to achieve wide angles of view, but this process has its drawbacks. It's inconvenient to set up, a tripod must be used, it takes work to stitch the images together, and stitching does not always respond well to images that contain moving subjects.

I've also owned a couple of wide-angle lenses over the years: the Sigma 14 mm f/3.5 lens and the Sigma 12-24 mm f/4.5-5.6 lens. Both of these lenses easily captured the wide angles of view that I was after, and were a lot of fun to use, but they simply did not have the optical quality needed to maintain image sharpness across the frame. I felt that there was too much vignetting and that the image corners were not very sharp.

Canon has offered a 14 mm f/2.8 lens for many years. I tried one once, and it was a fine performer, but I did not feel that the improvement over the Sigma version was dramatic enough to justify the higher cost. I decided to continue using my existing tools while waiting for something better to become available.

So you can imagine my excitement when Canon introduced an updated version of their 14 mm lens last year, which they claimed delivers "higher image quality overall including superior peripheral image quality." Could this be what I'd been waiting for all these years? It certainly sounded promising, and I put it on my wish list.

Finally, I took the plunge and acquired this magnificent chunk of optical glass for my very own. I was very excited! I put it on my Canon EOS 5D, which has a full-frame sensor to take full advantage of wide-angle lenses, and took it for a quick spin to try it out. I was not disappointed. At last, I am getting both the angle of view and the image quality that I was after. While a 14mm is not an everyday lens, it has quickly become one of my favourites.

Here are my first pictures, taken in and around the University of Waterloo. (You can click on each image to enlarge it in a new window.)

Canon 14 mm lens (1) Canon 14 mm lens (2) Canon 14 mm lens (3) Canon 14 mm lens (4)


While these are just some quick shots to try out the lens, I'm looking forward to unleashing my creativity with the use of dramatic wide angles!

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On November 28, 2008 4:04 PM, Blogger Cathy wrote:

I ran across your photography of Curacao and I would like to buy a copy of one of you photographs. My husband and I got married on the beach in Curacao last June and I would like to give him a framed photo of the shot you took of the beach at sunset. I believe that is where we got married. (We got married on the property of the Curacao Hilton overlooking the rocks). Please email me and let me know if I may purchase this photograph as I would like to give it to him as a Christmas gift.

By the way, you are an amazing photographer.

Thanks,

Cathy Grigg
 
On November 28, 2008 7:01 PM, Blogger Sassan Sanei wrote:

Hi Cathy,

Thanks for your request and kind words. Unfortunately, I have no way of getting in touch with you. If you see this reply, please contact me at the following email address:

blogger (AT) sassansanei (DOT) com
 
Is this joke funny or not funny? You decide.
Q: Why did the cricket have trouble falling asleep?
A: Its cicadan rhythm was off.

("Nine months and that's the best you can come up with?")

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On September 30, 2008 11:51 AM, Blogger mark wrote:

bwahaha.
\
genius.
 
On October 09, 2008 12:24 AM, Blogger James wrote:

Definately punny, puts me in mind of the long string of truly terrible puns that ran on System III bbs for a while back in 86 or 87
 
That one with the red thing
I decided to let Ryan watch a little TV this morning. Usually we try not to do this too often, but I thought he might enjoy it. Ryan is three and a half years old -- an age where the "and a half" is still relevant. Communicating with young children can be a challenge, because sometimes they don't use the best words for getting their idea across, and that leads to confusion and miscommunication. Come to think of it, it's that way with a lot of adults too.

Sassan: Ryan, would you like to watch Mickey Mouse Clubhouse?
Ryan: Want to watch Mickey Mouse!
Sassan: Okay, we'll watch one episode. Which one would you like to see?
Ryan: The one with the rocket ship!
Sassan: Sorry, I don't think we have that one. Let's see what we do have! We have Mickey's Treat, Pluto's Best, Donald the Frog Prince, Daisy in the Sky, Goofy the Great, Minnie's Birthday, Donald's Big Balloon Race, Pluto's Puppy-Sitting Adventure, Sleeping Minnie, Donald and the Beanstalk, Goofy's Bird, Goofy the Home Maker, Mickey Goes Fishing, A Surprise for Minnie, Mickey's Treasure Hunt, and Minnie Red Riding Hood. Which one of those would you like to see?
Ryan: Umm, umm, that one, the one with the red thing.
Sassan: The red thing???
Ryan: The one with the red thing! The one with the red thing!!! That one!
Sassan: What red thing?
Ryan: The red thing! The red thing! Umm, umm, Goofy's Bird.
Sassan: Oh, that red thing!
Ryan: That one! With the red thing!
Sassan: Okay.
Ryan: What Daddy didn't know what Ryan meant for?

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On May 05, 2008 11:51 AM, Blogger Deb wrote:

February. It is now May. Your daughter is probably shopping for her prom dress and you have yet to post pictures.

Come on blog buddy, keep up with the demand. :-)
 
On August 25, 2008 3:34 PM, Blogger Deb wrote:

I think I'll leave a comment a day until you come back.

MWA HAHAHAHAHAHAHAAAA
 
No way out
I'd sure hate to be stuck in this traffic jam! (Click on image for a larger view.)

Worse than gridlock, it's deadlock


Sorry I don't have the original source to credit the image.

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I'm not sure what to make of this question
My three-year-old son Ryan just asked me:

How come sometimes Daddy doesn't know everything more than Mommy?


Is that a good thing, or a bad thing? I don't know.

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On January 16, 2008 1:13 PM, Anonymous Anonymous wrote:

That's priceless! Right up there with Nathan inquiring "Mama, penis go?"
 
The 10 tastiest foods on this, or any other, planet
Here is a list of the 10 tastiest foods on Earth and elsewhere. (This is different from my list of 10 favourite foods that I previously posted, because a favourite food isn't necessarily the tastiest food, or vice-versa.)

10. Pepperoni stick
9. Buttered popcorn
8. Orange creamsicle
7. Old El Paso cheese dip
6. KFC
5. Earl Grey tea
4. Blue bubble gum ice cream
3. A&W Cream Soda
2. Nutella
1. Reese's peanut butter cups

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On December 22, 2007 11:53 AM, Blogger mark wrote:

i put it to you that the name of this blog should be " sassan, the blog of a house husband"

how's life as a live-in dad going?
 
On January 03, 2008 3:29 AM, Blogger tercumenette wrote:

 
Hello Blogosphere. I have NO IDEA what this means. Any suggestions??
I found this word list in an unsent message in my Drafts folder. No recipient, date, or subject line. I have no idea what it's doing in there; all I know is that I must have written it at some point. I'm going nuts trying to figure it out, and would appreciate any suggestions! Thank you!

Denim
Clorox
Alimony
Mentholatum
Argot
Linoleum
Xerox
Polonius
Masonite
Pandemonium
Steponum
Kryptonite
Latrine

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On December 10, 2007 6:53 PM, Blogger Laura wrote:

Something similar to this post a la periodic table?
 
On December 19, 2007 1:12 PM, Blogger Deb wrote:

Lex Luthor's shopping list?
 
Life after BlackBerry
I've decided to leave my job at RIM and become a full-time, stay-at-home dad to my two young children, Ryan and Megan.

It's a life-changing decision, and people react predictably to this news. If they have children of their own, they are generally very supportive. They say something along the lines of "You're doing a wonderful thing! They're only this age once, and they grow up so fast. It's great that you can take this time to do it."

On the other hand, those who do not have children of their own invariably ask, "What are you going to do with all your free time?" I forgive them the absurdity of this question, because they clearly have no idea what it's like to be around two very busy little kids all day long. They go non-stop, and they don't take breaks. The concept of free time went out the window a long time ago. But thanks for asking.

Leaving work wasn't easy. I started working at RIM in 1996, before there was even a BlackBerry. As an electrical engineering student, I was intrigued by the idea of wireless data communication, which was still in its infancy. I knew that RIM was on the verge of something big, and I wanted to be part of it. The entire company consisted of about 50 people when I joined. Today, it has grown to more than 7,000 employees, including some of the best and brightest minds in the field. The company measures annual sales in the billions of dollars, and has made BlackBerry a recognizable brand name around the world. By any measure, RIM is a huge success story.

I have had an amazing time at RIM. I truly enjoyed working with the people and technology that make the company great. It was a difficult decision to give that up and spend every day raising my kids, who are too young to understand or appreciate the value of what I am doing for them, and who often behave in a thoroughly unpredictable and irrational manner. It isn't the fun and games some people think it is. There are tantrums and unreasonable requests, and a good night's sleep is a thing of the past. It makes me cranky sometimes. But parenting is all about challenges and sacrifices, and this the life I have chosen for myself.

So now that my parental leave is over, I've left my position indefinitely. Tomorrow morning, and every day after that, instead of throwing my laptop bag over my shoulder and heading into work, I'll be at home, changing poopy diapers and teaching the ABC's. Of course I'll miss going into work. But I also know that if I went, I would be missing something even better.

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On December 02, 2007 7:30 PM, Anonymous markoos wrote:

wow mate. that's massive. good luck and i wish you well. i can sorta empathize about the lifestyle change (though i gave up full-time work to study), it's gonna be great.

i look forward to the interesting blog posts.
 
On December 03, 2007 11:14 AM, Blogger Deb wrote:

That is so cool. I expect lots of picture posts, which by the way have been lacking, considering the addition of the new kid.

You and markoos both are brave souls.
 
On December 07, 2007 2:45 PM, Blogger Laura wrote:

Huge news - congrats! I look forward to more adventures of Sassan the super-dad :)
 
There is no right answer to this question
"Are you going to share your Hallowe'en candy with your sister?" our neighbour asked Ryan while trick-or-treating, referring to his 7.5-month-old sister Megan.

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On November 12, 2007 3:14 PM, Anonymous Anonymous wrote:

That's funny! In our household, it was much easier - Nathan did the legwork collecting candy, went to bed, and WE enjoyed ;)
 
Rap lyrics translated
This is awesome.

Rap lyrics translated

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On October 31, 2007 4:11 PM, Anonymous Anonymous wrote:

Those the ones I like ‘cause they don’t get nathan’ ... what does my son have to do with Ebonics and rap music?! What does Nathan mean??
 
Which Friends character are you?
Fun little quiz...



Which Friends Character Are You?

You are Ross. You're intelligent and adored by your parents. However, your lack of social skills causes you to talk too much and try too hard. While your friends pick on you for your nerdiness, they better watch our for your rage.
Find Your Character @ BrainFall.com

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On October 31, 2007 4:09 PM, Anonymous Anonymous wrote:

Oh my god! I did this quiz and came out as Monica!! So not only am I your sister in real life ... but I'm also your virtual-quiz sibling?! Geez ...
 
To the other people waiting in line with me at the passport office
To the other people waiting in line with me at the passport office, I would like to share a few things about my three-year-old son Ryan:

1. Telling me to "control your child" as he breaks loose from my grip and runs off assumes, incorrectly, that I am unaware of what has just happened or that I could easily have prevented it. It further suggests that it's any of your business. Wrong again.

2. A nicer word for you to use might have been "precocious."

3. Actually, he's saying "Fun! Fun! Fun!" You did not hear what you think you may have heard.

4. Yes, I do plan to take him onto an airplane; that's usually why one obtains a passport. I am also aware that it is an even more confined space than the passport office. Painfully aware.

5. I too would like to harness half his energy!

6. I know it's not a toy. But it looks like fun. Thank you for your heartfelt concern.

7. He's THREE. I'm tired. Give me a fucking break.


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On September 21, 2007 1:02 PM, Anonymous Anonymous wrote:

This is 3 years old boy full of energy. What else one would expect from him? Sitting at the corner and reading The Globe and Mail or working on his laptop checking the stock market?
To whomever doesn't appreciate the healthy energy of a 3 years old child: you either never had a child or you had a rotten childhood.
Gma :)
 
On September 24, 2007 2:56 AM, Blogger mark wrote:

i agree. ti's so rude that they'd actually say something.
 
On October 09, 2007 2:47 PM, Anonymous Anonymous wrote:

From one parent to another (and as your sister who cares about you) I have 2 words that I want you to turn into your mantra when dealing with judgmental busy-bodies who obviously can't understand the simple concept of a toddler/young child being full of energy: FUCK 'EM
 
Sassan and Janet Simpson
This is awesome!


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World War II poster
This is a Canadian poster from World War II -- "Lick them over there! Come on Canada!" Doesn't it make you feel patriotic and proud?

World War II poster


World War II, for those of you who don't remember, was the biggest war since World War I.

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On September 11, 2007 8:24 AM, Blogger Deb wrote:

yeah okay.. that one made me snicker in a juvenile fashion.

hehe