Pixel Perfection

Photoshop at the core of its coding is a pixel or bitmap editor. That is not to say there is not some powerful algorithmic Mojo going on under the hood. So what am I talking about there? There are two processes that generate graphic images, these are bitmap and vector graphics. The image above is what the big deal is all about. Both sides of the image have been enlarged the same amount. So why has the left side pixelated and the right has not. (As a side note the left side shows a good example of artifacting.) Earlier I had traced the logo with the pen tool in Photoshop to generate a vector mask that can be scaled without any distortion, pixilation or artifacting. So how does it do this. First here is an example of what the two mean:

To the right you can see an example of vector vs bitmap graphic. The lines are the same size yet the vector line is so much smother. When a pixel is enlarged it maintains its squareness is the best way to describe it without going all tech-geek.

Now having mentioned the g word, we are going to get into it in short order. A vector graphic uses mathematical equations to generate a path to which a line may be drawn. Take a point in space as a reference, give it an direction and magnitude and the resulting point is called the sense. The element between the starting point and the sense is a vector path. When the vector path is stroked it becomes a bitmapped line in Photoshop. This is a simple line, curves are another animal.

To make a sin wave as shown below the equation below the wave is applied.

What this equation does is generate coordinates based in input values at specific points on the graph where only one shape of line may connect the projected points. Take the projected numbers on the simple chart below. Of the five sets of numbers they define a specific path for the line to be generated.

So how does all the relate to Photoshop? Have you ever noticed that when you are scaling text it maintains shape and definition? Then if you rastorize the text layer then enlarge the text, it does not scale as well and will eventually pixelate. shapes are the same thing. That is the best explanation for the difference between bitmap and vector graphics. The next time you go dragging a pen handle to stretch a curved arc, just think about all the number crunching that is going on behind the scenes. 

Ok so I got s little techie on this post but it was a fun little look into the mind of Mr. Adobe.

Take car all... Doug

Hard Core Monday

Here is the Techno-Geek Alert. Those not interested in Lightroom... Cya tomorrow!

If you are still here this is a process in Lightroom that has similarities to iTunes library and play lists. You can look at this way. The Library is the database holding all the information about the contained images, The folder is physically where the images are stored. The Catalog is like the iTunes Music Library, it's all there, you just don't necessarily know where and what you have unless you look through all the stuff. Collections on the other hand are very much like the play lists in iTunes. The hang up is how to get rid of bad images when you are never going to look at them again. Read on!

What we have here is what Lightroom looks like just after an import from a card.

You can see that 13 images have been imported in the Previous Imports Catalog. This is the ideal time to go through the images and do your picks and rejects, keyword, and possibly rate the images.

Once you have made your picks and rejects you can go to the Photo menu and select Delete Rejected Photos, or use the keyboard shortcut of Command-Delete (Ctrl-Del on Windows) and accept the Delete from Disk option. The images are removed from the drive and sent to the trash. It does not however remove any files from you backup folders. That can be another post all together.

Like I said, that is the ideal way to take care of house cleaning. All too often though we make an import to get the images onto the drives and come back later to work with them. From here on we will cover deleting images after a successive import has occurred. Below you can see the Para Glider Collection has been crearted with 13 images. The same 13 images that are in the Previous Import Catalog.

This next scree capture is simply to show that once an import has been accomplished, the Previous Import Catalog is cleared and the new imported images have a temporary place to live. Notice the 1 in previous Import and 13 by the Para Glider Collection!

Now we are picking, rejecting, rating, and color coding our images in the Para Glider Collection. Here is where Lightroom gets a little funky. Flagging only resides in the current Catalog or collection. You can see in the two images below how this is reflected. The upper is the Collection and the lower is the All Photographs Catalog. Notice how the star rating and color coding transfer but the picks and rejects flags do not.

SIDE BAR

If you try to Delete Rejected Photos while in the Collection it will only remove them fro the collection and not the disk.

The next tow screen captures illustrate the quickest way that I have found to delete images from the hard drive when originating in a Collection.

1. Open Collection
2. Flag images to be deleted and rejects (X)
3. Filter for Flagged as Reject (the black flag)
4. Select ALL (Cmd-A)
5. Change to All Photographs Catalog
6. Flag images to be deleted and rejects a second time (X) as these images should already be selected.
7. Delete rejected photos (Cmd-Delete)
8. Accept Delete from Disk

The selected images in step 4 above remains selected when you change to the All Photographs Catalog.

Every application has its quirks and idiosyncrasies but Lightroom is just a dynamite application for image management. Possibly Adobe could add one option in the removing from a catalog dialog window. My vote is for what you see below!

Cya.. Doug

How Many Lenses Do You Need?

Most photographers would say that is an easy question to answer. One more.

But then again, there are many reasons to limit the number of lenses you have in your optical arsenal. Purist say stick with as many prime lenses as you can get your hands on because they say the optics are more precise vs the moving optics in zoom lenses. The portrait photographer will swear by a good 85mm or a 70-200 mm zoom. Nature can go both ways... Landscape will go wide while wildlife will go long as will sports photographers.

Ok... So that may not be much help to answer the question. To tell you the truth, I can not answer the question. By the simple fact that Canon has over 60 lenses to choose from, the need is so diverse that the original answer may be the best... One more

Here is a breakdown on the lenses shown in this post.

A - EF 14mm f/2.8 L II USM $2299

This baby has 114° of view so you are almost looking at your feet when shooting. It is the closest lens to a fisheye and still maintaining minimum distortion. This is great for architectural and very wide landscape. It is a prime lens in that to change the focal length would require a different camera body (APS-C sensor based body).

B - EF 16-36mm f/2.8L II USM $1649

While not quite as wide as the 14mm this lens has a zoom capability that makes it very good for a metro walk around lens.

C - EF 85mm f/1.2L II USM $2149

This lens is coveted by portrait photographers for it's wide aperture of f/1.2. This easily generates soft bokeh in images. The price is the most restrictive on this lens. You are either doing a lot of portraiture or you have a nice dose of disposable income.

D - EF 50 f/1.4 USM $520

This lens is really an ideal lens for the APS-C sensored bodies such as the 40D, 50D, and Rebel line. With the 1.6 crop =factor this lens acts like it is an 80mm lens. Very nice for the cost.

E - EF-S 18-200mm f/3.5-5.6 IS $199

Ok... This one seems a little out of place in this line-up. First it is Canon's consumer level lens but is a relatively new design. Specifically it is designed for the cropped sensor. The "S" in the EF-S designation stands for Short. That being the back part of the lens is closer to the camera body than a full EF lens. This lens would interfere with a full framed sensor such as the 5D Mk II, or 1DS Mk III. Having said all that. this has turned out to be a fine lens. A nice reach (320mm) and yet goes wide (18mm)when necessary.

G - EF 70-200mm f/2.8L IS USM $1999

This is probably one of the best lenses in the Canon line-up. It encompasses that magical 85mm and can be racked out to compress the field without having to back up into the next county. The stabilizer can give up to four stops of additional light. Just a fantastic lens. On an APS-C (cropped) sensor it runs at 112-320mm. So what does this have over the EF-S 18-200? Bigger and higher quality glass and constant aperture of 2.8. It may not sound like that much but it is really big!

H - EF 1.4 x II Extender $299

This little device mounts between the long lenses such as the 70-200 and turns it into a 98-280mm on a full frame or 156-448 on a cropped body. That is some really nice flexibility. The only down side to strapping this buddy on is that the is a one stop loss in light. There is a 2x extender but that looses two stops. Most people call these teleconverters.

Ok now... We are moving into the twilight zone in lenses.

I - EF 400mm f/2.8L IS USM $7999

You will see this lens on many football field, make that professional football sidelines. You have seen many of the products of this lens in Sports Illustrated. The glass is nice and fast at f/2.8 and allows very high shutter speeds to freeze the action. Oh, did I say it was a bit pricy.

J - EF 600mm f/4L IS USM $9199

The monster lens in the Canon line-up. It is the wildlife photographers lens of choice. Speed is not as necessary as reach. This is how they get that tiger looking into the eye of the camera. Somewhat beyond my budget though.

I have eluded to the APS-C sized sensors in this post for a reason. Having a cropped and a full framed sensored bodies doubles the utility of your lenses. That is with the exception of the EF-S lenses. So if I have any recommendation, it is this:

1. Get the best glass your pocket book can afford.
2. If you plan to have both sensor sized bodies, avoid the EF-S lenses.
3. Remember you feet! They are the ultimate manual zoom.
4. Shoot with one lens for a day to find out its limitations.
5. Practice... Practice... Practice... You parents were right after all!

Take care all... Doug

NOTES

I believe some of the Nikon bodies will accept the Nikor lenses that are designed for the full frame or crapped sensor. I am no where near as familiar with the Nikon line as I shoot Canon.

Lens Flare

What is lens flare? The geek zone will tell you it is the refracted or scattering of light from within the lens elements. Even the best lenses have flare, it is just very well controlled by the quality and treatment of the elements within the lens.

The closer in alignment with a light source, the greater the possibility of flare and zoom lenses with more elements are more susceptible to flare than prime lenses.. Glare is a good example as it is most definitely a result of lens flare. As glare goes it is a broad refraction of light that causes the glare. Often a curves adjustment on Photoshop can do wonders with mild glare.

Below is a shot I took last week of the sunset in Leland Michigan. A nice composition that is lost by the flare of the sun. There is a specific reason for this flare that I will get into shortly. Needless to say this is not an example of great photography.

In discussing lens fare in a training presentation I am putting together, I have used two images that demonstrate lens flare. The first image on the left is not only a flare condition but also glare. With lenses you do get what you pay for. The image on the left is actually from a closed circuit camera with a very inexpensive lens. On the right flare is still evident even on a high end lens. In this case it was a Canon EF 28-104 f/4 L USM lens. But is this the fault of the lens?

Zoomed in you can notice a slight halo of light around the sun, this is balanced flare that is acceptable. The flare or second sun in the 7 o'clock position from the sun is not a result of the Canon lens at all. Rather it is the reflection on the UV filter screwed on the front of the lens. Actually I had a circular polarizer on the front of the UV filter as well.

The diagram above shows how lens flare is generated by use of filters in front of the manufacturers glass. The further from a center aligned light source, the greater the flare effect as well as glare.

Solution: There are a number of ways to mitigate lens flare. First is to not shoot into the sun or bright light but that is often unpractical. Second is to use quality glass. The third and what I should have done in the first image above is to remove any screw-on filters from the front of the lens.

I support the position of a coated daylight or UV filter for normal shooting to protect the front element of an expensive lens, but I should have removed it for that series of shots.

Hey, that does it for me today. Take care... Doug

Bad Blogger

My apologies to anyone who looked at the "FINALLY - Canon Steps Up" post. It must have been in stealth mode but is fixed now.

Doug

F I N A L L Y - Canon Steps Up

The long long long awaited announcement by Canon about the replacement to the very popular 5D was announce just before Photokina in Germany a couple of weeks ago. It sure seem that Nikon has been kicking the proverbial Canon butt for most of 2008. I like the competition as it makes the company at the top of the heap step it up. But is it enough? Ultimately time will tell.

No I have not shot with this camera and what you see below is what you can find on the Canon website with some exception. This is the paraphrased version of that information.

Quick Summary:

The EOS 5D Mark II has a 21.1-megapixel full-frame CMOS sensor with DIGIC 4 Image Processor, an ISO Range of 100-6400 (expandable to ISO 25600). It supports Live View shooting and Live View HD videos. It can shoot up to 3.9 fps, has 9 AF points plus 6 AF assist points, a new 98% coverage viewfinder, a 3.0-inch Clear View LCD (920,000 dots/VGA) and a rugged build.

Here are abbreviated specs form the Canon site. Scroll down to see the continuation of the this blog posting. 

Specifications

Type
Recording Media	CF Card Type I and II, UDMA-compliant CF cards, via external media (USB v.2.0 hard drive, via optional Wireless File Transmitter WFT-E4A)
Image Sensor Size	36.0mm x 24.0mm (35mm Full-frame)
Compatible Lenses	Canon EF lenses

Image Sensor Type Large single-plate CMOS sensor Pixels Effective pixels: Approx. 21.1 megapixels Total Pixels Total pixels: Approx. 22.0 megapixels Aspect Ratio 3:2 (Horizontal: Vertical) Dust Deletion feature (1) Automatic sensor cleaning (2) Manual cleaning of sensor (3) Dust Delete Data appended to the captured image

Recording System Recording Format Design rule for Camera File System 2.0 Image Type Still: JPEG, RAW (14-bit, Canon original), sRAW1, sRAW2, RAW+JPEG Video: MOV Color Space sRGB, Adobe RGB Picture Style Standard, Portrait, Landscape, Neutral, Faithful, Monochrome, User Def. 1-3

Image Processing Type Auto, Daylight, Shade, Cloudy, Tungsten Light, White Fluorescent Light, Flash, Custom, Color Temperature setting Auto White Balance Auto white balance with the image sensor Color Temperature Compensation White balance correction: ±9 stops in full-stop increments White balance bracketing: ±3 stops in full-stop increments Blue/amber direction or magenta/green direction possible

Viewfinder Type Eye-level pentaprism Coverage Vertical/Horizontal approx. 98% Focusing Screen Interchangeable (Eg-D: Grid lines, Eg-S [point of Focus], Eg-A standard focusing screen provided Mirror Quick-return half mirror (transmission: reflection ratio of 40:60, no mirror cutoff with EF600mm f/4L IS USM or shorter lenses) Viewfinder Information AF information (AF points, focus confirmation light), Exposure information (shutter speed, aperture, ISO speed, AE lock, exposure level, spot metering circle), Flash information (flash ready, flash exposure compensation, High-speed sync, FE lock), Image information (Highlight tone priority, monochrome shooting, maximum burst, white balance correction, CF card information), battery information

Autofocus AF Points 9 AF Points (1 Cross Type) + 6 AF Assist Points Metering Range EV -0.5-18 (at 73°F/23°C, ISO 100) Focusing Modes Auto, One-Shot AF, Predictive AI Servo AF, AI Focus AF, Manual focusing (MF) AF Point Selection Automatic selection, manual selection AF-assist Beam When an external EOS-dedicated Speedlite is attached to the camera, the AF-assist beam from the Speedlite will be emitted when necessary.

Exposure Control Metering Modes 35-zone TTL full-aperture metering Evaluative metering (linkable to any AF point) Partial metering (approx. 8% of viewfinder at center) Spot metering (approx. 3.5% of viewfinder at center) Center-weighted average metering Exposure Control Program AE (Shiftable), Shutter-priority AE, Aperture-priority AE, Creative Auto, Full auto, Manual exposure, E-TTL II autoflash program AE Exposure Compensation Manual: ±2 stops in 1/3- or 1/2-stop increments (can be combined with AEB) AE Lock Auto: Applied in One-Shot AF mode with evaluative metering when focus is achieved Manual: By AE lock button

Shutter Shutter Speeds 1/8000 to 1/60 sec., X-sync at 1/200 sec. Self-timer 10-sec. or 2-sec. delay Remote Control Remote control with N3-type terminal. (Wireless remote controller RC-1/RC-5 can also be used.)

Drive System Drive Modes Single, Continuous, and Self-timer (10-sec. or 2-sec. delay) Continuous Shooting Speed Max. 3.9 shots/sec.

Live View Functions Shooting Modes Still photo shooting and video shooting Focusing Quick mode (Phase-difference detection) Live mode/Face Detection Live mode (Contrast detection) Manual focusing (5x/10x magnification possible) Metering Modes Evaluative metering with the image sensor (still photos) Center-weighted average metering (video) Exposure Simulation Provided Silent Shooting Provided (Mode 1 and 2)

LCD Monitor Type TFT color, liquid-crystal monitor Monitor Size 3.0 in. Dots Approx. 920,000 (VGA) Coverage Approx. 100% (viewing angle: approx. 170°) Brightness Adjustment Auto, 7 levels provided

Image Playback Display Format Single image, Single image + Image-recording quality/shooting information, histogram, 4- or 9-image index, magnified view (approx. 1.5x-10x), rotated image (auto/manual), image jump (by 10/100 images, index screen, by shooting date, by folder), slide show (all images/selected by date/folder) Highlight Warning Provided (Overexposed highlights blink)

Customization Custom Functions Total 25 Camera User Settings Register under Mode Dial's C1, C2 and C3 positions My Menu Registration Provided

Interface USB Terminal For personal computer communication and direct printing (USB 2.0 Hi-Speed) Video Out Terminal (1) Video OUT terminal: NTSC/PAL selectable (2) HDMI mini OUT terminal

Power Source Battery One Battery Pack LP-E6 AC power can be supplied via AC Adapter Kit ACK-E6 with Battery Grip BG-E6 attached. Battery Check Auto Power Saving Provided. Power turns off after 1, 2, 4, 8, 15 or 30 min. Date/Time Battery One CR1616 lithium-ion battery Start-up Time Approx. 0.1 sec.

So! Is it going to be worth the upgrade? That really depends on what you are doing with a camera today. Will it bring back the Canon shooters that bailed to Nikon in the last year? Personally I don't think so. If you are a Canon shooter using a 20D, 30D, 40D, or even 50D that has not loaded up on EF-S lenses it could be tempting. The portrait shooter that is running a 5D, start saving now, you want to go to the Mk II. Here is how I see it.

Nikon Shooter

Nikon makes an outstanding line of cameras, great glass and are the best challenge to Canon. My recommendation is to keep you gear unless you are moving into digital but that has it's own conditions. When bot Canon and Nikon went to auto-focus lenses, Canon decided to change the lens mount to the chagrin of most of the Canon shooters. Nikon decided to not abandon their owners and mad the body backwards compatible with the exception there would not be auto focus on the older lenses. I think that was a great move by Nikon and one that probably started Nikon on its move dominance in the market.

20D-50D Shooter

If you have a bunch of EF-S lenses then stay with the cropped camera. If you are heavy in the EF lenses, going with the 5D Mk II will essentially double your lens selection if you hang on to the cropped camera. Let's say you have a range of lenses on the from 16 mm to 200 mm. Your minimum effective focal length was 25.6 mm and now is a true 16 mm. with both cameras you end up with an overall range of 16 mm to 320 mm (448 mm with a teliconverter)

5D Shooter

Put you camera on e-Bay as soon as you can and put it towards the 5D Mk II. Bit depth and the ability to crop in post on a 21 MB file will maintain a very high resolution. Not if shooting at such high ISO's is not enough.

As for me. I have the 40D and there just is not enough to upgrade to the 50D. The 5D Mk II however is a different story. Portrait photography can have no better friend than the 5D line and now that the 5D Mk II is a reality, it is a no-brainer. David Ziser has a saying in photography and it goes like this, "photography just gets cheaper, better, and faster". At a price point 1K less than the original 5D the 5D Mk II will be a winner for Canon.

Take care all... Doug

More HONL

Today is not going to be much but I forgot to get this in yesterday. The Honlphoto guys also sell a gel kit that is fantastic. As you can see from the image above the gels have a strip of Velcro attached to them and they just press onto the attaching strip that is already on the speedlite.

Color Correction: 

• Cinegel Quarter Blue (1/4 CTB) 
  
• Cinegel Tough 1/2 PlusGreen 
  
• Cinegel Tough 1/4 PlusGreen 
  
• Cinegel Roscosun CTO 
  
• Cinegel Roscosun 1/2 CTO 
  
• Cinegel Roscosun 1/4 CTO 
  
• Cinegel Roscosun 3/4 CTO 

Effects: 

• Roscolux Primary Blue 
  
• Roscolux Moss Green 
  
• Roscolux Light Red
  

I am really looking forward to using the little gem's Aha... gels.

Cya... Doug

More Cool Toys

Here is some cool gear that will allow you to make more and possibly better use of those all to scary speedlites. These devices from Honlphoto (Honl is the guys name) go on you speedlite in a flash (take the pun however you want). There is a strip that has a rubber no slip material on one side and a bunch of Velcro on the rest of it. This strip wraps around your speedlite and allows you t attach the devices via Velcro.

In the photo above the first image is the speedlite with the strap attached, BTW there is no sticky stuff here so don't worry. The second image is an 8" snoot that wraps around the attachment strip and Velcro's together to make the round snoot. What is neat about this is that it can be stored flat. I have a Pelican Case that stores my two 580 EX II's and the transmitter, and now the Honl stuff goes on top.

Anyhow, the third image is calls a grid. The one I picked up is the 1/4" grid. It has a couple of straps that attache it to the strap on the speedlite. It goes on really really quick. It is a little bulkier that the snoot but I think it gives a little better and more consistent performance than the snoot.

The above three images are a test I made with the Honl light modifiers. There were all shot with an EF 50 mm f1.4 USM lens at about eight feet from the wall. I manually focused as it was sending the AF up a tree with nothing to grab onto. Each had the flash go off and was set at 1/250 exposure with a f/2.8 aperture. The first image is the straight flash, the second had the snoot, and the third was the 1/4" grid.

All in all each of the modifiers has there strengths. I think the snoot can be closed down some. It all depends on how you bring the Velcro together. The grid though is just flat cool looking.

Take care... Doug

Tech Tuesday: Stabilization

There have been some discussions in the blogosphere regarding lens based stabilization vs body based stabilization. Before we get into the differences, lets ask what and why about stabilization.

What & Why

First and foremost, stabilization is simply to reduce the effect of camera shake. This could be caused by vibration from the platform one is standing on, wind, nerves, or simply the process of aging. A byproduct of this stabilizing effect is the ability to run a slower shutter speed which is a major cause of camera shake not mentioned above. The what is one of two possibilities; that being the moving of the lens or sensor is such a way that negates a certain level of camera movement.

Shake

Stabilizing an image from shake allows the photographer a certain leniency regarding how stable he or she holds the camera. There is an inherent shake that occurs with a telephoto lens where any movement at all will be exaggerated by the zoom factor of the lens. Stabilization allows a sharper image for a given focal length when hand holding.

Shutter Speed

In low light conditions the photographer can slow the shutter speed allowing more light to increase the exposure. This extra time must be compensated for by holding the camera frozen still. This is usually done by using a tripod. Another traditional methodology is to use faster glass or open up the aperture as much as you could to soak in as much light as possible. Stabilization now allows the photographer to slow the shutter speed that results in a 2 to 4 stop equivalent. This technology paired with the new very high ISO (3200 and 6400) cameras provides the photographer the ability to take natural light photos in conditions that a couple of years ago would have been unheard of.

Lens vs Sensor

Nobody debates the benefits of stabilization, the controversy comes when it comes to body or lens based stabilization. It appears the two largest camera manufacturers (Canon and Nikon) have gone the way of lens stabilization. Others have decided that body based stabilization would be more beneficial to the end user. The issue I see comes down to cost vs performance. So which logic is better. It seems the less distance (amplitude) an object has to move, the more often (frequency) the object can be moved. What is this saying?

Lens Stabilization

When camera shake is sensed the the movement mechanism will adjust one of the lens elements to redirect the image so the sensor picks-up the photons as though the camera was not moving. Each stabilizing lens mechanism is specifically designed for that lens.

Body Stabilizing

IN this case when shake is sensed, the stabilizing mechanism will position the sensor to where the image is being focused. The benefit to this design is that all lenses mounted on the camera become stabilized.

Which one is Better

Well, there are pro's and con's for each of the. For lens stabilization the costs added is tremendous for each stabilized lens but the stabilization is designed for that particular glass set. For body based stabilization there is no additional cost for lenses. On the other hand the process is generic. This might be ok for shorter lenses, but there is some question if the sensor movement is adequate for longer lenses. A telephoto lens will cause a greater deviation and the concern in the blogosphere is that there swill be a sacrifice in performance with these lenses.

Conclusion

Clearly body based stabilization is much more cost effective than lens based but there is a reason that Canon and Nikon have stood by the lens stabilized process. Some may say that the big two simply want to grab more money for each lens. I beg to differ as professional photographers overwhelmingly choose either Canon or Nikon systems. They choose gear based on performance and dependability, not necessarily cost.

Caveat: The diagrams are not intended to emulate the actual process of each type of stabilization but rather provide a rudimentary graphic of each of the processes.

Take care... Doug