Tamron


Early Spring is a great time to be out in the woods, especially on a sunny day – the trees may still be bare, but the forest floor is bursting with life… the under-story plants, shrubs and smaller trees rush through their flowering and leafing cycles quickly, to take advantage of the unrestricted sunlight – in a few weeks, once the trees leaf out, the canopy blocks off most of the light, and the small bushes go into the “quiet survival mode” until Fall when they get their chance in the sun again!

I’ve been out with the Sony Alpha 700 and the Tamron 70-300mm f/4-5.6. The choice of lens for woodland photography may seem surprising, but I find that the Tamron is very useful – the extended zoom range (the 70-300mm is equivalent to 105-450mm) on the Sony Alpha provides an useful stand-off distance so one can zoom in on an intresting flower or bud from a distance of at least 5 feet away without having to brave the underbrush and wicked looking brambles – the woods around here are chock full of wild raspberries and dog rose brambles. This also has the advantage of not blocking the light.

Besides, the Tamron 70-300mm is also a 1:3.9 macro, and since can focus down to 5 feet at the extended end of the zoom range, it does a great job. Moreover, I marvel at the fact that the Sony’s built in anti-shake allows me to handhold the 450mm equivalent lens. I would never have been able to do that with my manual Olympus bodies or even the auto focus Minolta 800si.

By the way, I purchased my Tamron lens about 8 years ago, back in June 2000 – I know they still make this lens, but I am not sure how the build quality has changed, or if it is still made made in Japan. I’ve always been very pleased with the Tamron, and even more so now…. with it’s super-zoom length of 450mm f/5.6 and equivalent when mounted on the Sony Alpha 700, it’s a formidable piece of optical engineering, and very cheap at the price. This is a true “cheap awesome lens”.


Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm

Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm
Tamron AF 70-300mm

Photographed with a Sony Alpha 700 and Tamron AF 70-300mm f/4-5.6 lens. I used a Polarizer.



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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.

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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.



Creative Commons License
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.

On this last trip to Colorado, I has planned to drive out into the mountains in the evenings after work. My goal was to make it out to Estes Park, near the entrance of the Rocky Mountain National Park. I did make it there, but it started raining heavily, and my plans to photograph Estes lake and surrounding areas was a bust.

I did manage to get around though. On the advice of a colleague, I took Pearl Street west to Canyon Road, and drove out of town meaning to get a closer look at the rocky outcrops just outside of Boulder, CO. I’d originally intended to drive out to the famous Flatirons, but it was late by the time I got out of the office, so I settled for the shorter drive.

Canyon Road runs alongside Boulder Creek, and is very picturesque. I have to commend the City of Boulder for all the parking available by the roadside, practically every couple of hundred yards. I pulled over at a couple of places, and just sat by the beautiful rocky stream. Here are some of the pictures. I got the smooth effect on by shooting the stream at 1/8 of a second at f/11 with a polarizer. I didn’t have a tripod, so I braced myself on a nearby rock.


Boulder Canyon
Boulder Canyon
Boulder Canyon
Boulder Canyon
Boulder Canyon
Boulder Canyon
Boulder Canyon
Boulder Canyon
Boulder Canyon
Boulder Canyon
Boulder Canyon
Boulder Canyon

Boulder Creek 1/8 sec at f/11
Boulder Creek 1/125 sec at f/11
Boulder Canyon

Photographed with a Minolta Dynax 800si, Maxxum 35-105mm and Tamron 70-300mm lenses and Fuji Superia 400.


text and images © 2007 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners.
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I was in Boulder CO earlier this month (a work related visit), but I stayed in a hotel in Louisville CO, since it was much cheaper (and easier) to get a room, and besides, it’s only 10 minutes from Boulder. Louisville is a nice place, lots of places to get a decent meal.

I was exploring one evening and just driving along north from my hotel, when I stumbled upon this little gem of a recreation area. Davidson Mesa is an “open space” with minimal impact trails, and it’s the one place to get a clear view of the Front Range without any buildings and traffic getting in the way. It’s one heck of a resource for the good citizens of Louisville and surrounding areas.

For this trip, I had lugged my big Minolta Dynax 800si along with the Tamron 70-300mm and Phoenix 35-105mm, and for good measure, an old Vivitar 24mm f/2.8 (OM-Mount) with a OM-Maxxum adapter. The film was 400 and 200 speed Fuji film.

I’d have liked to have used higher resolution 100 speed film, but I had 2 zooms with me, and besides, the light in the foothills changes rapidly, and I wanted to have the additional latitude. On my last trip to Colorado last year, I had some 50speed slide film with me, and I was limited to using my 50mm f/1.7 since none of my other lenses were fast enough to handle the extra slow film.

I had the Tamron lens on the camera that evening and the Vivitar 24mm f/2.8 OM mount lens with a Bower adapter to fit it on the Minolta. I had included the zoom in my camera kit at the last minute, just in case I wanted to photograph some of the hard to access rocky crags along Boulder Creek. Normally one would not associate a long zoom with landscape photography, but the distance was just right to encompass the open space.

With ISO/ASA 400 film, the Tamron 70-300mm is great for portraits as well – just set to about 100mm and open to f/4 and you’ll get a couple of feet of depth of field, just enough for a person, throwing everything else pleasantly out of focus. I took a couple of pictures with the Vivitar 24mm as well, the Bower mount works like a charm. I just set the camera on manual and exposed at 1/500 sec at f/11.

I also wanted to get a soft and fuzzy view of the distant mountains, and emphasize the foreground and trail… there was also an interesting fence going off into the distance that I wanted to work into the composition somehow. For the soft shots, I used the camera on Portrait mode, hunkered down to minimize camera shake, picked the foreground subjects (rocks and grass) and shot.

There was a storm in the mountains that day, so the lighting near the Mesa was spectacular. The grass simply seemed to glow… modern film emulsions do a great job in capturing subtle colors, but some things are just too ethereal to capture. I did my best.

Here are the pictures from Davidson Mesa. The second picture is from another park right across the road from the Mesa parking area. It’s called Harper Lake.


Davidson Mesa
Harper Lake

Davidson Mesa
Davidson Mesa
Davidson Mesa
Davidson Mesa
Davidson Mesa
Davidson Mesa – Vivitar 24mm f/2.8
Davidson Mesa – Vivitar 24mm f/2.8

These pictures were also taken near Louisville, from a lookout point on Rte 36

Rte 36
Rte 36
Rte 36
Rte 36
Rte 36
Rte 36

Photographed with a Minolta Dynax 800si, Tamron 70-300mm f/3.5-4.6, Vivitar 24mm f/2.8 with Fuji Superia 400 film


text and images © 2007 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners.
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More pictures from the trip to Mt. Vernon. I had posted a bunch of pictures I had taken with the Olympus Trip 35 at Mt Vernon a couple of weeks ago. These were taken with my Minolta Dynax 800si and the Tamron 70-300mm and Maxxum AF 35-105mm lens.

I used the Tamron 70-300mm on the Potomac river cruise, and it was a great choice for the nesting Ospreys. They are raptors that resemble eagles, but they seem to be at home right on the water, nesting on the green buoys. The Maxxum AF 35-105mm was more suited to photographing the buildings and surroundings.


Mt. Vernon; Maxxum AF 35-105mm
Mt. Vernon; Maxxum AF 35-105mm
Mt. Vernon; Maxxum AF 35-105mm
Mt. Vernon; Maxxum AF 35-105mm
Mt. Vernon; Maxxum AF 35-105mm
Mt. Vernon; Maxxum AF 35-105mm
Mt. Vernon; Maxxum AF 35-105mm
Mt. Vernon; Potomac River Tamron AF 70-300mm
Mt. Vernon; Potomac River Tamron AF 70-300mm@300mm
Mt. Vernon; Potomac River Tamron AF 70-300mm@300mm
Mt. Vernon; Potomac River Tamron AF 70-300mm – Ft. Washington
Mt. Vernon; Potomac River Tamron AF 70-300mm – Ft. Washington
Osprey nesting, Potomac River buoy Tamron AF 70-300mm@300mm
Osprey nesting, Potomac River buoy Tamron AF 70-300mm@300mm
Mt. Vernon from Potomac River Tamron AF 70-300mm@300mm

Photographed with a Minolta Dynax 800si, Tamron AF 70-300mm f/3.5-5.6, Fuji Superia 200; with Polarizer


text and images © 2007 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners.
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The Thunderbirds were the closing act the the Joint Services Open House Air Show at Andrews Air Force Base. This year the Airshow was held May 18-20th. The 18th was only for Defense Personnel and Contractors, the 19th and 20th was for the general public.

The arrangements were superb – everyone had to drive to Fedex field, park there, and take a bus to Andrews. The organizers had arranged for so many buses, that no one had to wait for more than a few minutes. In fact, it took longer to get through the security checks.

The Marines doing the checks were firm and polite and kept folks moving. Food was not permitted, but they let me take my camera equipment. At Andrews, I continued to be impressed at the impeccable arrangements – the Airplanes neatly laid out, the clean Portable Toilets, the numerous food concessions for every taste, the drinking water tanker tenders strategically located. They even had facilities to wash hands after visiting the portable toilets. Imagine that.

To get the best view of the Thunderbirds, I made my way to the front, as close to the runway edge as possible. I used the Tamron 70-300mm lens and Fuji 400 Superia film. By the time Thunderbirds were in the air, the hazy sky had cleared up. I was lucky to get a clear view of the flyby zone. Since I was shooting at 300mm, I had a narrow field of view, and had to track the planes for a few seconds as they flew by to get the shots. Next time, I’ll probably be able to anticipate better.


Air Force Thunderbirds
Air Force Thunderbirds
Air Force Thunderbirds
Air Force Thunderbirds
Air Force Thunderbirds
Air Force Thunderbirds
Air Force Thunderbirds
Air Force Thunderbirds
Air Force Thunderbirds
Air Force Thunderbirds
Air Force Thunderbirds

Photographed with a Minolta Dynax 800si camera and Tamron 70-300mm f/3.5-5.6 lens on Fuji Superia 400 film. The exposures were between 1/750- 1/350 second, at f/5.6 to f/9.5


text and images © 2007 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners.
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I finally got to go to the Joint Services Air Show at Andrews Air Force base this year. I’ve heard about it for years, and the fine photographic opportunities. Besides, where else could you get a chance to see a F-35 Joint Strike Fighter up close? The Thunderbirds were scheduled to perform as well, and I heard that there would be a bunch of old warbirds on display as well.

I was debating on what camera equipment to take, since it was my first time at a real air show, finally played it safe and took the Minolta Dynax camera with the Phoenix 28-105mm for the wide shots and since I really wanted to get close to the action, I also took along the Tamron 70-300mm and lots of Fuji 400 speed film.

The Airshow was back in mid-May, but I haven’t had a chance to post all the pictures I took – the Thunderbirds will have to wait for another day. The remarkable thing about this airshow is the level of access – how close one can get to operational warplanes from all the services. The organization is another thing altogether – I think they take it to another level. The transport arrangements were fantastic, everything was like clockwork. Truly amazing.


JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007
JSOH 2007

Here are the pictures of the Vintage war birds. Seeing them side by side with todays sleek aircraft makes it even more amazing.

Vintage Warbirds
Vintage Warbirds
Vintage Warbirds
Vintage Warbirds
Vintage Warbirds
Vintage Warbirds – that’s my Sunny admiring the Dinosaur Airplane
Vintage Warbirds
Vintage Warbirds
Vintage Warbirds

Photographed with a Minolta Dynax 800si and Phoenix 28-105mm f/2.8-3.6 and Tamron 70-300mm f/3.5-5.6. I used a a Polarizer and Fuji Superia 400 film. It was very sunny, so the exposures were all approximately 1/200-1/250 second at f/13


text and images © 2007 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners.
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