Points in Focus Photography

Today for me has been spent mostly writing code, not my favorite pastime, and tomorrow looks like more of the same. I did, however make it a point to fire up Lightroom to play a bit more with DFine2, a rather nifty looking noise reduction “plug-in” for LR.

As clean as my mark 3‘s image are, there are times when I want to push the image further than I probably should or want to get as much out of a high ISO shot as possible. Either way my quest for that, and a healthy desire to keep as much of my work-flow in Lightroom, lead me to DFine 2 from Nik Software, which advertises itself as a Lightroom plug-in.

“Plug-in”, that may be what Adobe calls it, and by extension Nik Software, however I don’t know if I’d call requiring a full export to TIFF to a mostly stand alone program a “plug in”. Generally I think of plug-ins as something that adds functionality from inside of the program it’s plugged into.

That got me thinking, a while back I started a Lightroom 3 wish list and adding “real plug-ins” to it seems like just time time to post something about it.

Wish list after the jump.

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Concept sketch.

My mom is in the slow process of redecorating her movie room; she’s decided she wants to hang “snack bar” posters reminiscent of what you might expect at an old time theater snack bar. What that means, as both photographer and son, the task more or less ends up to me to design and create the images. Not that I mind.

The concept I was presented with was to have a series of images of various foods, pop corn, soda, candy, that are styled as snack bar ads. Following that I’m envisioning capturing the elements that most evoke. Each image will carry a theme and color-scheme complementary to both the overall theme and the subject in each image.

I’m starting with the pop-corn poster, which I envision will look like the concept sketch to the right (no, drawing isn’t my strong suit). The subject matter is dominated by yellows, reds and white, so I’m thinking I’ll work with that color pallet for the image I’ll complement and accentuate the red stripes on the popcorn containers with a  red background. Tint my main light to warm up the yellows in the popcorn. I think, red and yellow will also work well as popcorn is suppose to be warm and buttery (also yellow) and red and yellow carry that connotation as well.

I’ve broken the image into it’s 3 key  layers. For the foreground, I’m thinking out of focus popcorn to frame the main scene and evoke a bit of the feel of a popcorn machine. The main scene will be two popcorn cartons overflowing in a sea of popcorn. Finely the background will be a nice red gradient falling off as it progresses away from the scene.

I’m expecting the real challenge to be lighting this. I’ll be working with only 2 speedlites and not much to go by in the way of proper light modifiers. My overall goals are to provide even lighting without any harsh shadows, while dealing with any spill not having a proper softbox will create.

Lighting Design
Initial Lighting Design Concept

The background will be lit by a 430Ex on a light stand directly behind the scene. It will be gelled red and probably zoomed to 70mm give or take. If everything is centered right, it should give me a nice symmetrical falloff on the background giving me darker corners. Which is what I’m looking for.

The main light will be my 580Ex pulling double duty, being triggered by a pocket wizard and triggering (by way of master mode) the 430 ex slave. I’m thinking I should probably gel it between half and quarter CTO to warm up the popcorn and cartons. I’m expecting it to be slightly to camera left, and above the camera shooting though a diffusion screen. That should take care of most of the shadow issues. The rest, if necessary, will be taken care of by large fill cards on either side of the scene.

Of course the technical challenges are only compounded by the budget, of which there is none to speak of. I suspect I’ll be pulling some serious Strobist style hackery to get what needs to be done, done. Who knows maybe something creative and useful will come out of solving problems as the come up.

Clouds as Art

Over the past couple of days I’ve been chasing a Spot-breasted Oriole thought he neighborhood in an epic game of telephoto cat and mouse. Mostly with the mouse, er bird, winning. In the mean time I’ve also been working on continuing the two open series, A Brief History of Focusing and Photographing Flowers as well as starting work on a 3rd series investigating the design of camera UIs.

The Bully
The Bully

I hate reading the rumors and rumor sites, they’re like a train wreck, horrible but so very hard to to look away from.

The rumor mill seems pretty consistent on the perspective that the next EOS 1D will be an APS-H camera, and why not Canon’s own Chuck Westfall mentioned that Canon is committed to the APS-H format sometime ago in a Tech Tips. Further, apparently sports and journalistic photographers have put their backing behind the continued existence of this third class format as well.

I think there are compelling reasons to move on at this point. APS-H may have made sense when it saved some money compared to the larger full frame sensor, and sensors were clearly exotic and expensive to make. That would be what 5 years ago? The EOS 5D, EOS 5D Mark 2, Nikon D700 and Sony Alpha 900 have shown that a full frame sensor can be packaged in a body that costs less than the 1D. Clearly if a full frame sensor can be made inexpensively enough to put in a mid-tier camera at acceptable profit levels, the same should be true with a top-tier camera. Sensor cost certainly shouldn’t be an issue, nor do I think it ever was, in the ~$4000 price tag on an EOS 1D body.

What’s worse, APS-H buys us nothing over a full frame sensor and costs us wide-angle. No where in the idea of a sports or low light camera does it say it needs to be crop too. But wait, crop gives us free telephoto, you say. Oh no, not when the pixel density doesn’t increase as well. The only way to make your sensor size act as a free teleconverter, relative to a crop from the larger camera, is to make the pixels in the smaller sensor smaller.

Camera Native Resolution
(in MP)
Native Crop Factor Resolution if Full Frame Resolution cropped to 1.3x
(in MP)
Resolution if Cropped to 1.6x
(in MP)
TC Factor for a 10.1MP image
1D 10.1 1.3 17 10.1 6.7 1.3
1Ds/5D-II 21.1 1 21.1 12.4 8.2 ~1.44
40D 10.1 1.6 25.9 n/a 10.1 1.6
Native crop factor is relative to a full frame image equivelent to a 135 format film frame.
The TC factor is the field of view equivalent crop factor compared to a full frame image when cropping to a fixed resolution.

So long as the APS-H sensor’s pixel density continues to remain behind that of it’s full frame cousins, as it should to keep those high ISO capabilities where they should be, it never will get as much “reach” as they do. In fact, if it wasn’t for the 50% drop in frame rate (which is almost certainly due to the 2x increase in data that needs to be processed) you’re be better off shooting with a EOS 1Ds Mark 3 and cropping to if reach alone was your objective.

For all that non-gain in reach, we really do lose wide angle. What makes it even worse, is that by sharing the full frame mirror box of the 1Ds, there is no specialized ultra-wide but crop glass. Even if Canon made a 12mm ultra-wide, let alone a 12-20something mm ultra-wide zoom, it will always be wider on the 1Ds or 5D than on the 1D. Of course this doesn’t mean that the 1D is useless for anything but sports but it is limited in a way that the Nikon D700 and D3 aren’t.

I just don’t see any advantage to keeping the APS-H format at this point. For a long time I felt that Canon’s APS-C bodies were the second class citizens in the Canon lineup. When compared to Nikon’s DX bodies, they certainly are. However the APS-H 1D is almost certainly the 3rd class citizen. It’s a cropped sensor with less “reach” than the current full frame ones and no access to crop specific glass to give it really wide angle coverage that the APS-C bodies have.

I was working on a new series about the history of focusing and focus aids when I looked outside and saw this the sky was turning simply amazing colors. Unfortunately, it was too late to go find a foreground worth including, but I wasn’t about to pass up the shot at the colors.

South Florida Sunset Color

South Florida Sunset Color

I’m in the process of writing a rather long essay on the evolution of focusing and focusing aids from ground glass to contrast detection, and everything in between. It’s probably going to be a while before I get that finished and this was interesting enough that I thought it warranted an aside.

Nikon has filed for a patent on a mechanism to embed what amounts to auto focus pixels in the imaging sensor itself. This would in affect solve the performance issues contrast detection autofocus poses.

A bit of background, contrast detection AF systems suffer from a number of limitations that prevent them from matching the speed of the simpler phase detection systems. There are three main problems that contrast detection systems need to overcome. First is pixel sensitivity, because the camera is using information from the imaging pixels, it’s not possible to tune the the autofocus pixels to be more sensitive to light. This means that the camera makes more of a trade off in autofocus speed as light levels drop.

The second issue is it’s nearly impossible to tell which direction the image should be shifted without performing very complicated image analysis on other parts of the image, and even then there’s no guarantee that will be right. This is because to the imaging pixels a front or back focused lens simply produces a diffuse blob.

The contrast detection problem, which way do you shift the focus? Both examples are out of focus, but to the sensor they simply appear as diffuse blobs.

The final problem is the required processing power. In a contrast detection AF system the camera’s processor is actually trying to quantitatively find the point where to pixels have the highest different in brightness. A phase detection system simply compares the brightnesses of each pixel in two different rows of pixels. In an in-focus image they two rows of pixels will be the same, in an out of focus image they won’t line up.

What it appears Nikon is doing is miniaturizing the optical path of prisms and lenses that feed our current phase detection sensors and embedding them in the actual imaging sensor in place of imaging pixels where they want the auto focus point to be. This givens a camera using this system all the speed and efficiency benefits of phase detection without requiring a mirror or other beam splitter to direct some light away from the sensor.

None of these problems apply to a phase detection system. Because of the way the prisms bend light the direction that the lens needs to be focused is already known (except in the case of a severe defocus situation). In addition the specialize pixels used in the AF array can be tuned to be sensitive at much lower light levels while maintaining a good signal to noise ratio so they can be read quickly. Finally, processing is almost a non-issue thanks to the limited number of pixels the actual operation being performed on them.

The only possible problem is that the camera has to interpolate image data to cover up the holes the autofocus pixels leave. But truthfully that’s probably not much of a problem at all. Cameras current map out defective pixels and replace their measured values with interpolated values from the surrounding pixels. Even the basic Bayer layout of the sensor requires interpolation to turn the RAW data coming out of the sensor into something we can understand as a picture.

What it ultimately boils down to is this could give a point and shoot the same AF performance SLRs have. Of course if you pair this with another Nikon patent for what looks like an interchangeable lens camera in the Olympus E-P1 style, you might be able to start putting together an image of what Nikon has in store for us in the future. One thing that’s clear this patent has the potential to close the performance gap between Point and Shoots and SLRs, and pave the way for a mirror free/prism free SLR that can maintain current autofocus performance levels.

The patent in question is number 2009016727.

Clouds

I’ve always liked clouds, not normal clouds but big cumulonimbus clouds. Especially when they’re back-lit in the morning or late afternoon. Abstract in nature, often with interesting lighting and tonalities and always impressive in scale. On that note, I shot these of a brewing storm a couple of weeks ago.

The setting sun lights riseing cumulonimbus clouds.

Faint crepuscular rays form though riseing cumulonimbus clouds.

Focus Today concluded round 2 of serious focus testing. What’s different this time from the last? A new target, a new alignment strategy, and some new results. Last time I looked at autofocus, I had enough problems focusing fast lenses that I was growing concerned that there was either a systematic design flaw or similar error in phase detection AF systems. I was seeing behavior with fast lenses on both Canon and Nikon bodies that would inconsistently focus depending on a verity of situations.

The good news, the new target dramatically improved auto focus consistency on both platforms and the new alignment strategy shortened setup time and aided accuracy. The not so good news is that I’ve determined that there is definitely a problem with my EF 50mm f/1.8 II and it may in fact be a much wider issue; though I guess you could say, what do you expect from a $100 lens.

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