A few days ago, I had my Minolta AF 50mm f/1.7 lens mounted on the Alpha for some family pictures. (The lens is a 75mm equivalent on the A700, and thus serves as a very fast medium telephoto lens ideal for framing ‘head and shoulders’ shots, especially effective indoors for Available Light photography. I’ll be posting some of the “candid” portraits in another post soon). Anyway, I was out in Carroll County, and driving up on Rte 97 north when I came upon the Union Mills Homestead and Grist Mill.

I’ve documented my use of the Minolta 50mm f1/7 as a landscape lens on my 35mm AF Minolta Dynax 800si elsewhere on this blog since I’ve had great fun with the Minolta 50mm lens in Colorado and other locations. Now that the Minolta is an effective 75mm, its still great for landscape and building photography, especially for capturing architectural detail – it’s a challenge if there isn’t much room, though.

I would recommend a 28mm or 35mm lens on the Sony Alpha for close-up architectural work. For old farmhouses and general scenery where you can step back far enough, the 50mm (75mm) is a fine choice, especially in low light conditions.

These photographs were taken at Union Mills Homestead, just off MD Rte 97 in Carroll County. Union Mills dates back to the 1790’s and has many stories to tell… being on the way to Gettysburg, it saw its share of Union and Confederate activity. You can read all about Union Mills Homestead here. I got to the site late in the afternoon – it was clearing up after a storm, and the post rain sunlight coming through the clearing clouds was bright and clean. Everything had a just-washed clean look.


Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Across the Road from Union Mills
Across the Road from Union Mills
Union Mills Homestead

Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead
Union Mills Homestead

Photographed with the Sony Alpha 700 and Minolta AF 50mm f/1.7 lens, ISO 200, Skylight filter under a sunny/cloudy/post-rain situation



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olympus/zuiko by Ajoy Muralidhar is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.
text and images © 2008 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners. thank you for visiting olympus/zuiko.

It was unseasonably warm last week, with temperatures in the upper 50’s and even 60’s. Tuesday morning was unusual, with moderately heavy fog all along Rte 27 running North towards Westminster. The mist changes the appearance of the familiar landscape, and the soft morning light makes for some excellent photographic opportunities.

As I drove along Rte 27, the mist slowly lightened until it was completely burnt off by the time I got to work. I stopped at several familiar spots along the way to take these pictures. I had the Sony A700, of course – with the Sigma 28-80mm still on it from last weekend’s hike along the Great Falls towpath.

The Sigma is an unusually light lens, and perfect for hiking. It’s no slouch when it comes to landscape and architectural photography either. On the Sony Alpha, the lens becomes a 42mm-120mm, which gives me enough flexibility for most landscape and architectural applications. Although I’d preferred top have a 35mm for street photography, 42mm is acceptable. Besides, a 42mm lens presents the world with a slightly better perspective than a 50mm, with no distortion at all.

The 2 close-up’s are included to show the macro capabilities of the Sigma 28-80mm.


Misty Morning
Misty Morning
Misty Morning
Misty Morning
Misty Morning
Misty Morning

Misty Morning
Misty Morning
Misty Morning
Misty Morning
Misty Morning
Misty Morning

Photographed with a Sony Alpha 700 and Sigma 28-80mm f/3.5-5.6 aspherical macro lens. Auto ISO, Cloudy white balance.



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olympus/zuiko by Ajoy Muralidhar is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.
text and images © 2008 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners. thank you for visiting olympus/zuiko.

Anyone ever hear of D.O. Industries? I had never come across any lenses from them until I suddenly ran into this little beauty on EBay, going really cheap. It seemed to be an enlarger lens, but it had what appeared to be a T-mount type threaded mount. A quick email ( an even quicker response from the seller) confirmed that the diameter of the threaded end was indeed 42mm, so I took a chance on it and picked it up, since I was looking for a 135mm lens that would fit on my Spiratone Bellowscope.

I already have a nice Spiratone 150mm f/4.5 bellows lens, but I’m the curious type, and more than that, the name of the 135mm lens intrigued me. The lens itself is small, and solidly built – probably 4 element (maybe 6). Not sure if it is coated. The body looks old and appears to have seen much use, and the paint has faded, but nice glass. It was probably a workhorse lens on someone’s enlarger for many years. It even came with the retaining ring, which is rare these days.

I did a little bit of research on D.O. Industries, and here’s what I came up. Apparently they were an importer and distributor for Fujinon lenses, and they also sold lenses under their own name (rumor has it that D.O lenses are made by Fuji. The optical quality certainly seems to bear that out).

D.O. Industries was started by a gentleman by name David Goldstein in 1972. The company is still around. They are now called Navitar, and you can read their timeline here. I’m glad they’re still around. They seem to be doing well in the current digital era with new imaging products. Innovate, Evolve or Die, right? The photography marketplace is pretty ruthless, with old-timer companies closing down almost every day.

In case no one’s noticed, practically every 3rd party lens company had names ending with –AR. It seems to have been vogue with photographic companies back in the day. You see products with names such as Vivitar, Albinar, Astranar, Rokunar, Lentar, Kitstar, Macrotar and so on. I’ve often wondered why.

When I tried to fit the lens to a T-mount, I noticed that the thread, while being very close, was just not right. It seemed to be more like 41mm, but the pitch was OK. I got around this by wrapping a piece of light cotton sewing thread on the lens thread, and it works just fine. Curious. As long as it works, I am happy.

The advantage of using a longer focal length lens on the bellows is that it permits a longer “stand-off” distance. A short focal length lens (35mm, 40mm or 50mm) can give greater magnification, but the focusing distance is very short, which means that the light is cut off drastically, and one has to use supplemental lighting. The longer focal length bellows lenses (75mm, 135mm and 150mm) can focus from 18 inches to as far as 3 feet away, which lets a lot of ambient light get to the subject. Besides, there’s room for the tripod legs if the subject is 24 inches or more away.

Since I was trying out this lens indoors, I just used a pedestal lamp with the Sony’s WB setting to Tungsten lamp. I used a Auto ISO setting. The exposure was 1/5 to 1/8 second, and I was able to stop down to f/8 to increase the depth of field. If I were outdoors in natural sunlight, I would have used 100 ISO and a smaller aperture.

The tripod permits the longer exposure without shake. To avoid inadvertent camera shake during release, I used the Sony’s self timer setting (Drive Mode button, and then select self timer 10 seconds). This ensures that there is minimal shake. The Sony doesn’t have mirror lock-up, but it’s superbly damped. The mirror return ‘snap’ doesn’t seem to affect the image in any way.

For subjects, I used some of my wife’s traditional jewelry. Without more ado, here are the pictures

D.O. Industries 135mm f/4.5 on Alpha 700
D.O. Industries 135mm f/4.5 on Alpha 700
D.O. Industries 135mm f/4.5 on Alpha 700
D.O. Industries 135mm f/4.5 on Alpha 700
D.O. Industries 135mm f/4.5 on Alpha 700
D.O. Industries 135mm f/4.5 on Alpha 700
D.O. Industries 135mm f/4.5 on Alpha 700
D.O. Industries 135mm f/4.5 on Alpha 700
D.O. Industries 135mm f/4.5 on Alpha 700
D.O. Industries 135mm f/4.5 on Alpha 700
D.O. Industries 135mm f/4.5 on Alpha 700
D.O. Industries 135mm f/4.5 on Alpha 700

The Bellows mounts to my Sony Alpha 700 with a standard Minolta AF-T mount adapter, and the whole thing goes on a cheap Velbon tripod. Nothing special. Here’s the setup.

D.O. Industries 135mm f/4.5 on Alpha 700 Setup
D.O. Industries 135mm f/4.5 on Alpha 700 Setup
D.O. Industries 135mm f/4.5 on Alpha 700 Setup

Photographed with a Sony Alpha 700 DSLR, D.O. Industries 135mm Emlarger lens (Fuji??) fitted on a Spiratone Bellowscope. Auto ISO with Tungsten light WB setting. Exposure was 1/5 second and 1/8 second at f/8 from a distance of about 24 inches. I used a Velbon Tripod.



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olympus/zuiko by Ajoy Muralidhar is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.
text and images © 2008 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners. thank you for visiting olympus/zuiko.

Just getting way ahead of myself here, but my friend Cliff got me thinking about the future Alpha models, and regarding Sony’s plans for the future Alpha 900. Now, this is just my own little thought experiment, and should be treated as such.

The current A700 DSLR is 12.24 megapixels. The camera frame is large enough to accommodate a full frame sized sensor and I’m guessing that Sony designers will just need to make minor changes to the external configuration. The A700’s ergonomics are excellent, so Sony probably won’t mess with that. The will need to upsize the CMOS sensor to a full frame 35mm format sized 36mm x 24mm.

What does this mean? Currently, in the A700 which uses the APS-C sized sensor (23.5mm x 15.6mm) with surface area of 366.6 sq.mm. A full frame 35mm format is 36mm x 24mm (approx 864 sq.mm surface area) which is about about 2.35x the APS-C surface area.

Assuming they keep pixel density the same as for the A700, a full frame A900 could be a mind-blowing 12.24 x 2.35 = 28. 76 megapixels. I say COULD BE. With so much surface area to play with, Sony would be wise to reduce the pixel density further, allowing the A900 sensor to run cooler, and thus avoid hot spots (and bad pixels). I’d venture to assume that they would try to keep the A900 in the 20 – 22 megapixel range, which would give Sony a nice buffer for future marginal “improvements”

It will be interesting to see what Sony will finally settle on for the Full frame A900. I hope they can keep the cost reasonable so that amateurs can afford them as well. As for me, the A700 is probably rugged and enough for my amateurish efforts.



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olympus/zuiko by Ajoy Muralidhar is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.
text and images © 2008 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners. thank you for visiting olympus/zuiko.

There’s a lot of confusion when it comes to using lenses designed for 35mm cameras on the current crop of Digital SLRS. Many photographers have sizeable investments in 35mm lenses for their film cameras, and for the most part their lens investments drive them towards a particular digital camera body, whether it’s Nikon, Canon, Minolta (Sony), Pentax or Olympus.

Luckily, all the manufacturers retained their old AF mounts, except for Olympus, which uses the newly designed Four-Thirds mount. Sony retained the Minolta ‘A’ autofocus bayonet mount for the Alpha series cameras, allowing all the fine 35mm lenses out there since 1986 to be used. The same goes for Nikon and others.

However, due to cost constraints at the present time, most digital SLRs use a sensor that is smaller than the 35mm format size of 36mm x 24mm. This smaller format is 22.7mm x 15.1mm, and is known as the APS-C format. Sony and Nikon (and others) use a sensor size that is approximately the APS-C format size. As can be seen, the APS-C size provides a much smaller image area, 342.77 square millimeters versus 864 square millimeters for the standard 35mm format.

When a 35mm lens is used on the current crop of digital cameras, the smaller sensor size means that the 35mm lens will now have a narrower angle of view (also called FOV or field of view) than when used on a 35mm film camera body. This is due to the fact that the 35mm lens creates an image on the film (or sensor plane) that is is sufficiently large enough to cover the 36x24mm frame it is designed for.

When used in a Digital SLR that has a smaller sensor (and thus image size), the image formed by the 35mm lens is still the exact same size as before, but the smaller sensor can only use a portion of it. In effect, this constitutes an “in-camera” crop. This cropping is determined by the ratio of the sensor size to the 35mm format size, distance of the image plane from the front of the lens etc.

In most of the cameras using APS-C size sensors, the ‘cropping’ is equivalent to using a lens that has a narrower angle of view (telephoto effect). This Crop Factor (also known as Focal Length Multiplier) is around 1.5x (Sony Alpha) 1.6x (Nikon). In some cameras, Canon uses a sensor size that is slightly larger, which gives a 1.3x factor (this is the APS-H format). The Four-Thirds system used by Olympus and Lumix (Panasonic) has a 2x factor.

The focal length does not really change, of course. The smaller sensor’s ability to register only a portion of the total image causes an APPARENT increase in focal length due to the cropping. This has the effect of using a lens with a narrower angle of view, the same as using a telephoto lens. (Luckily, the sweet center portion has the sharpest part of the image).

The image edges which may not be sharp, or have aberrations are cropped in-camera. For the user, it’s easier to remember by multiplying the focal length of the lens they are using with the factor for that particular body, and that gives us the APPARENT focal length.

A lot of the confusion can be eliminated by using the term APPARENT rather than EQUIVALENT. for example, on my Sony Alpha 700 (which has a 1.5x multiplier for 35mm lenses), it would be more accurate to say that my Minolta 50mm lens has an APPARENT focal length of 75mm, rather than saying my Minolta 50mm is EQUIVALENT to 75mm.

This apparent increase in focal length does not affect the aperture, so the APPARENT focal length of 75mm is still at a fast f/1.7. This will serve as an excellent portrait lens, since it can frame head and shoulders perfectly, but you’ll find yourself having to move back when you want to include more of the scene.

For most wildlife photographers, birdwatchers and even landscape photographers, the apparent increase in focal length can be a unexpected blessing – they get more ‘bang’ for the buck from their existing lenses. When coupled with the higher ISO capabilities of DSLR cameras and in-camera image stabilization that will let them handhold the camera in situations that would have required them to lug along a heavy tripod.

If you’re using a MACRO lens, such as, for example my Sigma 50mm f/2.8 (a very sharp lens with a true 1:1 macro capability) the apparent increase in focal length permits the macro subject to be fill the frame without moving in as close. Since the stand-off distance is greater, more light can reach the subject. The increased distance also helps when photographing skittish subjects that are likely to fly or hop away if approached too closely.

When the subject is framed in the Sony Digital SLR, it is seen that the Depth of Field is greater for the same magnification when compared to using the lens on a 35mm film camera like my Minolta Dynax 800si. This is a great advantage for macro-photography where depth of field and subject lighting are always problematic.

The whole situation is different when it comes to wide angle lenses. This is where most photographers are ready to burst into tears. The 1.5x or 1.6x multiplier effect holds good on the wide angles too, and this means that a normal wide angle like 24mm lens which would give a 74 degree field of view on a 35mm format camera will now only provide a FOV of 62 degrees or so, approximately that of a 35mm lens. In the same way, an ultra-wide 16mm becomes an apparent 24mm a 28mm is an apparent 42mm and a 35mm lens behaves like a 52.5mm normal lens.

Given the fact that most wide angle lenses are EXPENSIVE, no photographer would like to see his investment reduced to a moderate wide-angle or a normal lens. However, such is life. You win some, you lose some. To get a true wide angle on the Sony Alpha 700, I would have to invest in a 18mm to get 27mm (luckily, that’s included in the zoom range of my Sony 18-200mm lens that I bought with the camera). Since the 18-70mm is bundled as a kit lens, most owners will have at least a 27mm wide angle, albeit a slow one).

To get the 24mm, we’d have to invest in the very expensive Sony 16-105mm Zeiss coated zoom lens (apparent focal length 24- 157.5mm). Buying a faster wide-angle prime lens would be prohibitively expensive for any amateur, and even professionals would hesitate.

My advice? If you really need to shoot wide angle, just use your film camera. You can still buy a fine Sigma 24mm f/2.8 AF at a reasonable price. The Sigma 24mm is a good deal, since it had a matte black Zen finish that tended to flake off, giving the lens a “very used” appearance and usually marked down. This is just cosmetic, and does not affect the lens performance in any way.

The same Sigma lens was re-badged and sold by Ritz as their house-brand Quantaray lens, but with a different, more durable finish – but it’s still the same lens. Don’t be fooled by the appearance of either lens – this is a very high quality lens. Besides, you can always use the Sigma on the digital SLR as an apparent 35mm f/2.8 prime lens in place of a ‘Normal’ lens. You’d pay hundreds more to get a similar “designed for digital” Nikon, Sony or Canon lens.

Of course, all this talk about crop factors and multiplication factors will become moot when Full Frame digital SLRs become common. Canon already has one, and Nikon and Sony will follow shortly. In fact, I would not be surprised if the Sony Alpha 900 was not released in a few more months. When that happens, lenses will behave as they were designed and there will be no more confusion.

As for me, I rather like the fact that my Tamron 70-300mm now behaves like a 105mm-450mm super-zoom. With the Image stabilization turned on, I can actually hold that baby steady enough to use hand-held.



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This work by Ajoy Muralidhar is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.
text and images © 2008 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners. thank you for visiting olympuszuiko.