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So how do you tell the US version of the Sony Alpha A700 apart from it’s European cousin? The US version includes Sony’s version of the Minolta Grip Sensor, while the European models don’t.

This isn’t a case of Sony short changing European customers. Although the details are rather murky, it appears that the Grip Switch is made of a nickel alloy, and the European Union recommends that nickel not be used in proximity to human skin for lengthy periods. So apparently Sony decided to follow along with the recommendations and simply eliminated the grip sensor from the Alpha A700 models bound for Europe. This also applies to the add on vertical grip, the European models of both the camera and the accessory grip are sans the Minolta style grip sensor.

Here’s where everything gets sort of fuzzy. Apparently the recommendation is just that: a recommendation, not a law. So Sony probably wouldn’t have broken any regulations by including the grip sensor in European Alphas. No one seems to know whether Sony simply chose to voluntarily remove the sensor for the Alpha models sold on the European continent, or whether the European Union used some political muscle to force their hand.

No more phantom Eye-Start problems

Grip sensor on the Sony Alpha A700 helps prevent unwanted Eye-Start trigger, but don’t look for it in Europe.

Photo: Sony Corp, used with permission

Basically, the grip sensor is a useful addition to the Eye-Start system available in the Alpha A100 and many Minolta cameras. Eye-Start allows the camera to be in a low power standby mode until you raise the camera to your eye. When the camera senses your eye near the view finder, the camera changes to full operation, including metering, auto focusing, image stabilization, etc. When you move the camera away from your face, it returns to standby — a feature that can greatly extend battery life.

The problem with the eye-start system is that it can’t always tell your eye from your shirt sleeve or your pant’s pocket. Dangle an A100 on a neck strap while you wander about and the camera may turn on and off constantly as the camera falls against your clothing. It thinks it senses your eye, so it powers up the LCD, and attempts to meter and focus, even though you have no intention of shooting anything.

You can turn the camera off, but then if something really interesting turns up, you have to hope you don’t miss the shot while the camera goes through it’s start up sequence. Neither choice is very appealing, and many people have criticized the eye-start system because of the phantom power up cycles.

Sony listens to Alpha users

As I’ve said before, it appears that Sony listens to it’s customers, because they have corrected a number of issues that people had with the A100. One of the things they did was reach back into Minolta film SLR technology to bring back the grip sensor. If you have the grip sensor mode turned on, the A700 will remain in standby, even if it thinks you are looking through the viewfinder. Only when your hand is covering the sensor and your eye is at the viewfinder does the camera become fully operational. Or least that’s the way US versions of the A700 operate.

Grip sensor is not a pressure switch

If you are wondering why the switch has to be made of nickel, instead of some other material, the grip sensor is not pressure sensitive. Instead it actually uses a small electrical field across your skin to sense that your hand is there. So the sensor has to be made of a conductive material and Sony apparently couldn’t find an adequate substitute for nickel.

Many have pointed out the European Union recommendation are aimed primarily at things like ear rings and other body piercing jewelry. Simply touching nickel probably doesn’t present much danger for most users. Some people apparently have or are prone to develop allergic reactions to nickel. Let’s not forget the electrical current involved in the switch. It’s very small, but perhaps it could aggravate an allergy in someone using the Sony A700.

So no grip sensor for the Europeans, at least until Sony finds another material for the sensor. Does this mean that US cameras will cause allergies? I rather doubt it. There might be some people with a severe skin sensitivity that could be adversely affected by the nickel in the sensor. On the other hand, you find nickel in all sorts of products, from automotive controls to fountain pens to silverware. Most people aren’t bothered by these items — I sort of doubt that a camera control will have a much greater effect. Of course, I am not a doctor, so if you have a nickel allergy, you might want to discuss this with your medical adviser.

Remember that Minolta has made long use of a similar nickel grip sensor in the Maxxum/Dynax 7 and 9 as well as the A2 and A200. I haven’t heard of a rash (no pun intended) of photographers developing skin allergies from using these older Minoltas.

Why choose a electrical sensor over a switch?

Which leads to my next question, why exactly did Minolta choose to use the nickel sensor in the first place? A simple pressure switch would be cheaper, could be made of any hard materiel and could even be used with gloves on — something that can’t be said of the nickel sensor.

About the only reason I can think of for choosing the nickel sensor is that if you left the camera on when you put in a camera bag, padding or other equipment might possibly trigger both a pressure switch and the eye start system — running down the battery. Because the grip sensor actually measures current through your skin, it can tell the difference between a hunk of foam rubber and the fingers of your hand.

The Senswitch — forgotten Minolta technology

Yet Minolta long ago developed technology that could eliminate false triggers and didn’t require any electrical skin contact. Im refereeing to the Senswitch that appeared on the Minolta XK cameras in the mid seventies.

Minolta Senswitch is neatly hidden inside the grip on the XK Motor

The Senswitch was just simple pressure switch that turned the camera meter on when you touched it. It saved battery power, because the camera could be left in standby until the user pressed the switch.

I’ve heard that a lot of XK owners didn’t like the Senswitch on the basic XK model. It was just a long strip on the front of the camera, and apparently many photographers had trouble engaging the switch consistently. And it would also be vulnerable to pressure from other sources like the foam padding that could press upon it and drain the battery.

Minolta, however, followed up the plain vanilla XK with the incredible XK-Motor. This wonderful camera was my main shooting machine for many years, I loved the Senswitch on the XK-M, because Minolta moved it from the front of the camera to the inside of the built in grip. You would have to work awfully hard to miss engaging the Senswitch on the XK-M. If you were holding the camera by the grip, your middle-finger just naturally fell upon the switch. You almost couldn’t miss it.

Located deep inside the recess of the grip, the XK-Motor’s Senswitch was also fairly invulnerable to being pressed accidently by something other then your finger tip. I’m not saying it would be impossible for a hunk of padding or gear to engage it…but it would be a very rare occurrence. I never saw it happen in all the years I shot with my XK, Then again, I usually switched the camera off when it put in the bag.

One final thing. The XK-Motor’s switch was made of some sort of hard plastic , so you could use it with gloves.

It seems to me that Minolta had almost fool proof system with the XK-Motor’s Senswitch. Too bad Sony didn’t study the XK-M grip before opting for the nickel grip switch on the A700. It works even with gloves, it is fairly safe from accidental triggering and it won’t cause skin allergies. Oh yeah, they could sell the Senswitch in Europe as well.

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Bart Pasquale, who last appeared on these pages with his insightful comments on the Sony Alpha Full Fame - Antishake question, is back with a detailed analysis of the Sony battery for the A700 Alpha and it’s lack of compatibility with the A100 batteries.

The complete text of Bert’s email follows:

Hello Tom!

Here’s some info regarding the new Alpha A700 battery, the NP-FM500H. As you may know, there is a grove in the new battery, and a ridge in the A700 battery compartment, which prevents interchangeability with the A100 battery. I contacted my usual 3rd-party battery suppler from eBay, and he said Sony has blocked the manufacturing of NP-FM500H compatibles. It was not clear weather this is legal/political maneuvering, or simply an issue being able to reproduce the circuitry required for A700 to display the % charge remaining, but he expected something out of Taiwan by January. What he did know is that one person reported to him filing out the ridge inside their A700, and the A100 batteries did NOT power the A700.

A700 battery shown being loaded into new vertical grip. Notice the groove that allows battery to fit the A700 compartment.

Photo: Sony Corp, used with permission

Being the anti pay-for- proprietary-items consumer that I am, I find myself waiting it out to avoid buying a $80 Sony battery, understanding the implications of battery consumption suddenly became very important. So, I spent the past day and a half draining a fully-charged battery under controlled conditions. My goal was simple: take bursts of pictures throughout the day at various intervals, review the pictures, delete a few, and record the image count and battery charge remaining. Many batteries fall off very quickly once they indicate “half charged”, but SONY claims the new battery’s reported % is “accurate”, and the battery is good for 650 shots. Curiously, the second day I had the camera, I cranked off 900 pictures on a photo shoot, but the battery indicator still showed being more than half-charged. Let’s examine…

I began with a fully charged battery two days ago, At various intervals (a few hours to a few minutes) I would fire off 50-100 images, and review them, at a medium pace, deleting every few images as I went. I was shooting compressed RAW, anti-shake on, DRO standard. This simulates my camera use in the studio or shooting on location. After the first 50%, I continued to review the imagers quickly, but did not delete many images, as I might do to conserve battery power while on a shoot. The results are summarized in the following table:

	Shots	% Charge	Charge Drain Rate
Day One:	0	100%
	550	75%	1% = 22 frames
	1200	50%	1% = 26 frames
Day Two:	1800	25%	1% = 24 frames
	2600	1%	1% = 32 frames
	3080	Dead	1% = 400 frames

Over 3,000 shots from a single charge! I’ve never worked so hard to drain a battery. That was the battery’s third charge, so we’ll see how that changes after a couple dozen cycles, and how the generic versions hold up to that when they finally do come out. A few other statistics:

• Reviewing 150 images uses 1% of battery charge
• Leaving the display on for about 5 minutes uses 1% of battery charge
• Overnight, the battery looses about 2%-3% of it’s charge
• Straight shooting without reviewing images can achieve 30+ frames per percent at any phase in the charge cycle.
• Once the battery indicates zero charge, you can still quickly eek out a few hundred shots!
• This is about an extra 12% of charge not indicated in the charge level.

During recharge, the first 15 minutes were spent to achieve 1% charge status back. After that, it was pretty linear, adding about 12% every 15 minutes achieving 86% after 2 hours of charging. The battery indicated “100%” about 35 minutes later, but continued to take a charge for an additional 15 minutes to top it off. So, one could theoretically shoot 400 frames, recharge for 15 minutes while the model changes, and never run out of charge. Of course, YMMV; I don’t know how consistent one battery will be to the next. Happy shooting all!

- Bert Pasquale

BTW, I have a couple well-cared-for A100’s for sale! (With several extra batteries…)

Wow, that is a pretty exhaustive (no pun intended) sample of the battery life of the NP-FM500H when used in the A700.

I found it interesting that someone would actually go as far as removing the locking ridge from a new A700 to try to use the older battery. The fact that the NP-FM55H (used in the A100) would not power the A700 indicates to me that the ridge serves a purpose beyond an attempt to sell more batteries. It’s easy to point to an incompatibility like this and suggest it is being done to sell more batteries. I’ve found that manufacturers rarely make components less compatible just to move additional product. They have to stock additional components, manufacture additional components and distribute two lines of batteries instead of one. Usually is in the company’s best interest to stock and sell as many common items as they can, because that drives manufacturing and stocking cost down.

That said, several printer manufactures have taken great pains to make sure only their own cartridges work with their hardware. So who knows? This could be Sony’s attempt to eliminate after-market battery competition, but I doubt it. Usually when an electronic product carries a lock out ridge like the one described above, it is to prevent using a non-compatible item that might cause damage to the devise. The upshot is A100 batteries are NOT compatible with the A700 — don’t try to reengineer the camera or battery in attempt to make them work.

It Bert’s tests are indicative of how long a typical NP-FM500H will last, it seems like for most shooters a single battery will cover most assignments. A second battery, either used as a spare or inserted in the A700 Vertical grip should be more then sufficient power for most A700 shooters.

Thanks again Bert, this is a great report. If anyone is interested in Bert’s A100 gear, email me and I will get you in touch.

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Alphatracks has always been aimed at Sony and Minolta SLR users. Not that there is anything wrong with non-SLR gear, There have been numerous great non-SLR cameras sold under the Sony/Minolta brands. You have to draw the line somewhere, however, and since I have primarily used SLRs, I like to stick to what I know.

I’ve noticed that many readers are somewhat unclear as to which cameras are actually SLRs. Some appear to think it means any camera that uses interchangeable lenses. (Which is not the case.) Others mistakenly apply the term to so-called “bridge” or pro-summer cameras. These cameras typically rely on an electronic view finder (EVF) , which disqualifies them as a dSLR. So what exactly makes a camera SLR?

Shouldn’t that be a MLR?

It’s the instant return mirror (and supporting system) that puts the reflex into a SLR.

Most people know that SLR stands for “single lens reflex,” which in itself is fairly confusing. After all, nearly 100 percent of the SLRs ever produced are designed with an interchangeable lens mount. Shouldn’t these cameras be called Multiple Lens Reflex cameras?

To understand just why we refer to these cameras as single lens units we need to examine a bit of camera history, The early cameras, such as those used by Matthew Bradey during the American Civil War, recorded a single image at a time. The photographer looked through the lens, focused, composed and then inserted the film plate behind the lens to make an image. While the entire process was crude by today’s standards, the photographer enjoyed great control, since he looked directly through the actual imaging lens to compose the shot.

While this was satisfactory for still life, portraits and landscapes, this process did not lend itself to rapid photography. These early cameras could only record one image at a time. Which is why you have never seen a motor-driven view camera.

Realizing the need to offer sequences of exposures, camera makers begin to experiment with various roll-film designs, With a roll of film in the camera, the photographer could fire off continuous images without reloading. While this improved throughput dramatically, it caused another problem. The roll of film had to pass closely behind the camera’s optics, which meant that the photographer could no longer look through the camera lens to design the shot.

Rangefinder cameras appear to keep things in focus

There was no problem with the lower-end consumer roll-film cameras, because these generally used an inexpensive “fixed-focus” lens. Better quality optics require the lens to be focused, however, and as we’ve seen, the photographer couldn’t look through the lens with a roll-film camera. One of the first solutions to this problem was the Rangefinder — a type of camera that offered a distance measuring scale in the viewfinder. By determining the range from the viewfinder, the photographer could then adjust the focus to match — usually with very good results.

Twin Lens Reflex cameras offer another solution

Twin lens reflex used upper lens to focus, lower lens actually took the photo.

While the rangefinder type cameras worked well, the camera industry is always evolving. A second method of allowing the photographer to focus and compose appeared in the “Twin-Lens Reflex” cameras. These cameras used two identical lenses, arranged one on top of the other in the manner of an over-and-under shotgun. The film winds past the lower lens, while the photographer can focus through the upper lens. Since most of the twin-lens cameras were fairly bulky, designers added a mirror and ground glass to the top of the camera, hence the term “reflex.

Now the user could hold the camera at waist level and look down at the ground glass which previewed the image via the mirror behind the upper lens. As the user adjusted the focus on the upper lens, a gear mechanism moved the lower “taking lens” to match.

While both rangefinders and twin-lens cameras offered a credible way to focus and preview a shot, neither allowed the photographer to look directly through the imaging lens. This made exact composition difficult in certain situations.

SLRs take cameras another step forward.

Cut-away view shows the light path through a typical SLR. Light enters through the lens, hitting the lower mirror, where it is reflected upwards. It then strikes the top of the prism, where it is reflected again to strike the front of the prism. It is reflected yet a third time to pass through the viewfinder.

In their quest to allow users to see through the actual “taking” lens, camera makers turned to the periscope — a simple device using two mirrors placed at opposite angles to bend the light path. Periscopes are easy to understand — any kid can construct one from a couple of mirrors and some scrap wood. In a camera, the lower mirror is placed at a 45 degree angle directly behind the lens. Light striking the mirror is projected upwards to a ground glass. A pentaprism, which contains two additional mirrors, is located behind the viewfinder. The prism is used to flip the image so it can be viewed “right-side up”

There is just one hitch. If you’ve been paying attention, you no-doubt realized that the lower mirror blocks the light path to the film (or digital sensor as the case may be.) Now the photographer can look though the lens, but the image can’t be projected on to the film plane.

So the camera designers had to add another wrinkle. They had to move that mirror. Just long enough to make an exposure, since when the mirror moved, the photographer couldn’t see anything through the lens. So they designed the “instant-return” mirror.

At the instant of exposure, the mirror flies upward, the shutter opens, closes and the mirror snaps back down. It is a incredible feat, when you consider that instant return mirrors have to flip up and back in a heartbeat, over and over for the life of the camera.

Once the instant return mirror was perfected, photographers could once again design their images by looking through the lens. Unlike the twin lens reflex, this new breed of camera needed only one lens to focus and shoot with. So they became known as… you guessed it…. Single-Lens Reflex cameras.

Digital SLRs work exactly the same way — the same reflex system of mirrors and prism is used in front of a a digital sensor instead of film.

For further reading:

Wikipedia SLR page>

How Stuff Works - Single Lens Reflex

Images on this page published under the GNU Free Documentation License.

SLR Cutaway derived from image provided by:
Juhanson

Rolleiflex Twin Lens Reflex provided by
Jean-Jacques MILAN/Photographie - 40

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Sony’s first dSLR. the Alpha A100, was a great effort, but it did fall short in a few areas. From the e-mail and comments i get at Alphatracks, the biggest complaint about the A100 is that it didn’t offer a vertical grip option.

As I’ve pointed out before, this wasn’t Sony’s oversight. The A100 was based to a large degree on the very successful Konica-Minolta Maxxum 5D. For some unexplained reason, Minolta and friends crippled the 5D by not designing it to use a vertical grip. The 5D’s big sibling, the Maxxum 7D, did offer an optional battery grip, but the 5D was a different design and couldn’t use the 7D grip.

New grip adds 3.5 inches and a pound of weight to the A700

When Sony built the A100 on the chassis of the 5D, there was no provision for a grip. Sony would have had to heavily massage the 5D components to add grip connections and controls, making the camera more expense and most likely delaying the launch. So Sony wisely brought the A100 to market without an accessory battery grip.

Aftermarket vertical grips for the A100 selling briskly

This hasn’t stopped some aftermarket accessory makers from developing grip fro the A100. We’ve discussed the DeCain and Ownuser accessory grips on these pages in the past.

• Aftermarket Vertical Grips for the Sony Alpha and Minolta dSLRs
• The Sony A100 vertical grip saga continues
• Vertical grip options for the Sony A100 and Minolta 5D

Many photographers have had good experience with the aftermarket units, but since there are no internal contacts to allow a grip to communicate withe the camera, users have to put up with external cables to get the job done While it’s mice to have an aftermarket alternative, it’s obvious that a factory designed grip with internal connections would be a preferable solution..

When the Sony started to design the Alpha A700 dSLR, they started from scratch. Sony went to a lot of effort to make sure the Alpha A700 corrected any weaknesses inherent in the A100. One of the first things they did was add internal connections for a battery grip. The grip, known as the VG-C70AM is due to start shipping this month.

The two biggest demands for a vertical grip center around better handling when shooting in a vertical mode and the addition of extra battery power. Sony nailed both of these objectives with the VG-C70AM grip.

Vertical grip enhances the Alpha A700’s ability to shoot in the portrait orientation.

Everything the horizontal grip can do, the vertical grip can do as well

The new A700 vertical grip looks like someone took an A700, cut the standard grip off and glued it to a battery container. Every control and button that appears on the camera’s built-in grip is mirrored on the accessory grip — in virtually the same location. Anything you can do with the standard grip you can accomplish with the accessory grip as well. Since the A700 automatically rotates the menus on the camera’s big LCD screen, this results in an excellent vertical image making machine.

Two batteries are better than one

As far as extra power goes, the grip has provision for two NP-FM500H batteries, which Sony claims will produce twice the battery life. (Well, duh!) . You have to remove the camera’s standard battery to attach the grip, so you only have two batteries available — but that is still a major improvement.

Two batteries power the removable grip.

The question of weight naturally arises. The VG-C70AM weighs in at 10.1 ounces without batteries. Add two NP-FM500H power cells at 2.75 ounces each and the whole works is still slightly under 1 pound. The grip also adds about 3.5 inches (87.2mm) to the height of the A700 — a nice bonus if you have large hands.

Like he A700 itself, the VG-C70AM battery grip is constructed with an internal Magnesium-Alloy. Sony also says the unit has rubber gaskets to seal out dust and moisture.

Vertical grip should be forward compatible

Now there is good news and bad news. The bad news is that the VG-C70AM cannot be retrofitted to the A100, The A100 and A700 have completely different camera bodies and as we’ve already discussed, there are no internal provisions for a grip on the Alpha 100. So if you were hoping to bolt one of these bad boys to your A100, you’ll have to be content with on of the aftermarket solutions.

Ah, but there is a very good chance that the VG-C70AM will be fully compatible with Sony’s next dSLR; the famous Sony Alpha flagship. Based on the mockups shown last March, the A700 and the flagship share a common body. Thus the flagship (which many observers are calling the A900, although Sony hasn’t confirmed the name) will most likely be able to use the VG-C70AM. It makes sense, as it will save tooling and design costs if Sony can create a single grip for both models.

Rear side of the grip shows the thoughtful control layout.

Of course the standard disclaimers apply. Sony has only revealed a mockup of the flagship, so there is no guarantee that the A700 grip will be compatible. Don’t base your buying decisions on the mockup, as things could very well change. If I was a betting man, however, I would give you pretty good odds that the VG-C70AM will fit the flagship when it appears..

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Sony is offering a free firmware update for the A700. According to the release, the new firmware update

“improves image sharpness and reduces noise under certain circumstances and improves flash control at very short distances with non-ADI control lenses.”

Sony says the update offers:

• Sharper images for pictures taken under low contrast conditions
• Reduced noise for pictures taken at ISO 3200
• Improved flash control for objects closer than 1 meter with non ADI controlled lenses

In addition to the updated firmware, Sony is also updating the Image Data Converter SR and Image Data Lightbox SR applications included with the camera.

You can download the Windows and Macintosh versions of the firmware and software updates at the Sony Support site.

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This will be the final post on the Sony Alpha full-frame sensor / anti-shake quandary. The first in the series outlined the full frame with anti-shake problem, while the second consisted principally of remarks by Bert Pasquale, a well-respected optical engineer.

Since several readers are sill somewhat confused, I have created some illustrations to help explain the situation.

Figure one shows the relative sizes of various sensors, They are drawn to the exact size, but since monitors and screen resolutions vary, the sizes may not be correct on your screen. The size of each sensor in relation to each other, however, is accurate.

Figure 1: Sensor sizes compared

The red rectangle represents a “full-frame” 24×36mm sensor. The green rectangle is a 17×2mm APSC sensor. The blue rectangle is 90% of a full frame.

Figure 2 shows the APS-C sensor overlaid on a circle that represents the minimum coverage of a 35mm full-frame lens. As you can see, there is plenty of “wasted coverage” as only the area inside the green rectangle will be captured. It is obvious that the sensor can move freely in any direction and still be covered by the lens.

Figure 2: Coverage of a APS-C sensor by a full-frame lens

Figure 3 is a full frame sensor contained inside the exact same coverage circle. There is no established size for the coverage area, as lenses will vary slightly. The designers only have to create a lens that will offer adequate coverage and sharpness of the 24×36mm film area, and still fit within the lens mount. Of course, the greater the lens coverage, the larger and heavier it will need to be. It will probably be more costly as well, so typically lens designers try to keep near the minimum dimension.

As Mr. Pasquale mentioned, the circle of coverage doesn’t immediately fall off to nothing. Rather, the edge of the circle gradually starts to provide lens light and become less sharp.The fall-off increases slowly until the image eventually fades away.

As you can see from Figure 3, there is little room for the sensor to move without clipping at least one of the corners. Again this will vary from lens to lens, as well as with different focal lengths of a zoom lens.

Figure 3: Coverage of a full-frame sensor by a full-frame lens

Figure 4 is an arbitrary 90% sensor. You can see that such a sensor is much larger than the APS-C size, yet still has room to float inside the coverage area. I chose this because several people “in the know” have suggested they believe this will be Sony’s answer to the problem. However, some other authorities have suggested that Sony may opt for a 1.25 crop sensor.

Figure 4: Coverage of a 1.1 crop sensor by a full-frame lens

On the other hand, Mr. Pasquale has suggested that the sensor may not actually move sufficiently enough to require a “crop” lens of any sort. That would be ideal, but until Sony announces the sensor, we really won’t know.

The final figure is one suggested by Alphatracks readers Warren Massey and LEdgars. In their comments, they suggest Sony could simply build an oversize sensor. As you can see by the rectangular outline in figure 5, such a sensor can move some distance in any direction without clipping. The idea is that the big sensor can move around and the camera can crop to a 24X36mm dimension at exposure. it’s a novel idea — but I not sure we will see it in the near future.

Figure 5: Coverage of a oversize sensor by a full-frame lens

First off, it would be expensive. As sensors increase in physical size, the manufacturing yield is less because typically there are more rejects. Even more significant however, is that an oversize sensor would most likely be confined to the Sony flagship. A full-frame sensor would be attractive to many other dSLR makers and in the past, Sony’s sensor division has profited by selling sensors to a wide range of camera makers. Would Nikon have any interest in an oversize sensor? It’s rather doubtful. Nikon uses a lens based image stabilization method, so there wouldn’t be a need for an oversize sensor.

So if Sony does produce an oversize sensor, their principal customer would be Sony — and for the time being only for the top-of-the -line, limited-production flagship. Would that justify designing and manufacturing an oversize sensor? Or would Sony prefer to invest their resources in a sensor they could sell by the truckload to other camera makers as well as their own dSLR division?

Time will tell, but I’m guessing Sony has a plan up their sleeves. It should be quite interesting!

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Last week, I posted about the alleged difficulty of using a full-frame sensor with the Sony/Minolta anti-shake system. See the post: Can Sony build a true full frame dSLR? I made critical error in my post, when I suggested that the sensor had room to move up and down but not side to side. This is incorrect. The typical 35mm image circle only needs to cover the full-frame sensor from corner to corner, so there would be no room to move the sensor in either direction.

So I was mistaken, but sometimes mistakes can be a positive thing. My error encouraged Bert Pasquale, an optical engineer (and Sony/Minolta SLR user) to write me with his assessment of the full-frame, anti-shake situation. In addition to pointing out my little misconception, he has several innovative ideas on how Sony could deal with the problem.

I asked Mr. Pasquale for permission to reprint his comments and he readily agreed. His remarks follow:

Thanks for sharing your knowledge, Bert. This is exciting stuff! In camera, computer controlled gain? Falloff curve corrections. Sensor based warning that the stability could cause vignetting! Wonder how much of this Sony has considered — and more importantly how much they will actually implement in the Alpha flagship camera. Stick around. it looks like things are going to get really interesting. It looks like its a great time to be a Sony A-mount user!

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Can Sony really make a full-frame dSLR? Not will Sony…but CAN Sony really do it?

Some months back, I wrote that I expected the so-called “flagship” Sony Alpha (possibly named the A900?) to carry a full-frame sensor. I still believe that to be true, however I’m hedging my bets a little. It will be “almost” full-frame or “close” to full-frame. It may not be the actual size of a 35mm negative, however, which is the definition of a full-frame dSLR to most photographers.

It isn’t that Sony lacks the technology to build an actual full-frame sensor. Sony has the ability to build just about any sensor they could wish.

Super Steady Shot doesn’t play well with a full frame sensor

The problem is the Super Steady Shot (anti-shake) system. Not that there is anything wrong with SSS itself, the in-body image stabilization is one of the Sony Alpha dSLR’s major advantages. However, one of the Alpha’s other major advantages is that it can use the extensive line of Minolta A-mount autofocus lenses. And thereby hangs a tale.

Twenty-some years ago, when Minolta engineers were designing the original A mount glass, there were no digital SLRs and no anti-shake systems. Thus, there was no reason to design a lens to cover anything other than the standard 35mm film image.

Thus the AF A mount lenses were designed to project a circle that would encompass a 24 X 36mm area at the camera’s film plane. There was no need to cover a larger film plane, because no Minolta SLR offered a larger negative size.

Maxxum 7D and Antishake: no worries

When Konica Minolta engineers developed the Maxxum 7D, they designed an in-body anti-shake system. The system works by moving the camera’s sensor in relation to camera movement. In essence, if there is camera vibration, the sensor stays in one place, despite the lens and body movement. The same system is used in the Maxxum 5D, the Sony Alpha A100 and the Alpha A700. All of these dSLRs use a 17 X 23mm APS-C sensor.

See the problem? If Sony develops a 24 X 36mm full frame sensor, any lens will need to cover an area larger than 36mm — at least when SSS is turned on. If vibration occurs in an up and down motion, there is room for the sensor to move in relation. If, however, the sensor moves to the left or right, it could move outside of the area covered by the lens. Update: I was in error about room for up and down motion. See these remarks by an optical engineer to understand why the image would be clipped in any direction the sensor moves.

This isn’t an issue with the current Sony/Minolta dSLRs, since the smaller APS-C sensor has plenty of room to move in any direction without moving outside of the lens coverage. When you move up to a full frame sensor, however, there isn’t nearly as much breathing room.

Lens coverage varies

Of course lenses vary. Some of the existing Sony/Minolta lenses may offer enough coverage to allow the SSS system to move — but others would probably exhibit some vignetting if the sensor moves too far to the left or right. Who wants to drop a ton of cash on a professional dSLR when many (most?) of the available lenses might display some vignetting?

How will Sony handle the full frame design?

Sony can tackle this problem in a number of ways. The first could be to drop SSS for the flagship model. That makes little sense, since Sony would then have to develop a line of image stabilized lenses. If they are going to develop an entirely new lens line, they might as well design larger coverage lenses and retain the in-body image stabilization.

Neither of these options are very credible, however. As I said, one of the Sony Alpha’s major selling points is that you can use those millions of Minolta A-mount lenses. Start redesigning the lenses and there is far less reason to choose the Alpha over the competition.

The rumor sites are suggesting that Sony could eliminate any vignetting problem by reducing the sensor size. The sensor could still be much larger than the current 1.5 crop sensor, but not exactly the size of a 35mm film negative. The figure bandied about is 1.1 crop. That would indicate a sensor of something like 21.6 X 32.4mm.

I want my super wide angle lens back!

Loosing 3mm on the width and 2.5mm on the height doesn’t seem like a lot — but it will affect the camera’s ability to display the widest angle of view with current lenses. One of the biggest problems with the APS-C sensor is that most of the original A-mount wide angle lenses aren’t very wide any longer. Cropping a 35mm lens to APS-C size yields something equivalent to the “standard” 50mm lens on a full frame camera. A 24mm lens is now closer to a 35mm. Even a 16mm fisheye is will only show what you would see with a 24mm lens on a full frame camera.

So one of the prime reasons for choosing a full frame camera is to make all those Minolta wide angles truly wide again. A 1.1 crop would be much better than a 1.5 crop in this regard — but is it enough? That 16mm would now be equivalent to 17.6. A 35mm would look like a 38.5 lens.

Those differences seem fairly insignificant, but there are times when you need the widest angle of view you can get. I hate to give up even a millimeter when I am working with an extreme wide angle.

There is one other option that Sony could adopt. Create a full frame 24mm X 36mm sensor and allow the camera to use the full sensor only when SSS is turned off. Turning on the image stabilization would automatically turn off the outer ten percent of the sensor. This would give the best of both worlds. When SSS is engaged, the sensor size is reduced so there is no chance of movement causing vignetting. Turn the image stabilization off and you get the entire full frame area and the ability to shoot at your lenses widest field of view.

Taking a page from Nikon’s book?

This isn’t as far fetched as it seems. Until recently, Nikon didn’t have any full frame cameras in it’s line up, and they sold a ton of APS-C type lenses to go with their 1.5 crop dSLRs. With their all new full-frame D3, Nikon users who owned a bag full of 1.5 crop lenses faced a big problem. “Big N” sidestepped the issue of the APS-C lenses not covering the FF sensor with a switch that reduces the sensor to APS-C size when shooting with a 1.5 crop lens.

Sony could do the exact same thing with their offering, simply reducing the sensor to 90% when SSS is turned on. Of course to be truly useful, there would need to be some way of indicating the crop area in the view finder. This would probably be in the form of engraved lines on the ground-glass to show the crop area.

Would this be worth it? I’m not sure it would be worth the trouble and cost — but it would sure be slick.

If you were on the Sony design team, how would you handle this issue?

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Very interesting article on the hardwarezone.com website. Timothy Fernandez interviews Mr. Keiichi Ishizuka, Deputy Senior General Manager - AMC (Alpha Mount Camera) Division at Sony.

The article is well worth a read, if only for an insight into Sony’s plans for the near term and the future. It also provides an insider’s look into the design process behind the A700.

Although Mr. Ishizuka is somewhat careful not to reveal too much info about what is in the Sony pipeline, he does say that the flagship model ( the rumor sites are calling it the A900, but Ishizuka gives no confirmation of this ) is on track for next year. He also says that Sony is indeed developing a replacement for the A100 and hints that Sony may offer other new models — without saying when such models might be announced.

The bulk of the article discusses the new A700 and the design considerations behind it. Mr. Ishizuka cites picture quality as the top feature of the A700, and also mentions the engineering behind the Alpha A700 dSLR’s shutter and vertical grip. Ishizuka also takes Fernandez on an in-depth look at the A700’s new DRO option.

I expected the DRO to be a great feature. Having read Ishizuka’s comments, I am very excited about trying it out.

If you are a A-mount shooter (Mr. Ishizuka refers to it as the Alpha Mount), you should take the time to read the interview. Whether you are thinking of buying an A700, or you are concerned about Sony’s future plans in the dSLR arena, I think you find the interview very enlightening.

Check out the Keiichi Ishizuka interview at HardwareZone.com.

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The good folks at Tamron sent word that they have partnered with an outfit called Triscape to sponsor Digital Scrapbooking Day on November 3, 2007. Top prize is one of the all new Tamron AF18-250mm Di II All-In-One Zoom Lenses. If you’re curious about Digital Scrapbooking day, you can check out www.DigitalScrapbookingDay.com.

The good news, however, is that you don’t have to actually create a scrapbooking project to win. Apparently, there will be a straight drawing to determine the winner of the lens. All you have to do is send an e-mail to Tamron between now and December 10. It doesn’t get much easier than that.

If you are interested, click on over to:
http://www.tamron.com/lenses/digital_scrapbook07.asp and fill out your name and e-mail address.

Here are the rules from the Tamron site:

• No purchase necessary.
• One entry per email address.
• Employees and family of F+W Publications and Tamron USA, Inc. are not eligible to enter.
• Entries must be received by midnight 12/10/07 to qualify. Winner will be selected randomly from all entries and notified by 12/12/07 via email. If there is no response from the winner by 12/19/07 we will choose a new winner who in turn will have 5 business days to respond.
• Open to U.S. residents only.
• Void where prohibited by law.

The Di II All-In-One Zoom Lens is designed for APSC sensor digital cameras and is available in Nikon, Canon, Pentax and Sony mounts. I didn’t see anything about winner’s choice, but I assume whoever sends in the winning entry will be able to select which lens mount they want. No mention on the Tamron site that this lens is compatible with older Minolta dSLRs (7D, 5D), but if you choose the A-mount lens, I would think it would work with Minolta as well. Check with Tamron to be sure.

The 18-250 AF lens only weighs 15oz. and lists for $499. You can read more about it at www.tamron.com/lenses/prod/18250_diII.asp. I might just be willing to give up my e-mail address for a chance at winning one of these.

If you follow through and actually win the lens, be sure to let us know. I’m sure your fellow Alphatracks readers would like to congratulate you!

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