Tamron 18-270mm – a hero, but no VC…

After using Sigma’s 18-250mm optically stabilised zoom on Alpha bodies for a year and more, the first thing which strikes about the Tamron 18-270mm for Sony mount is the lack of the VC (Vibration Control) stabiliser found on the same lens made for Canon or Nikon.

Tamron’s lenses come without a case, but with a custom fit petal lens hood, front and rear caps. Design is clean with a Nikon-like sleeve grip and Canon-ish gold ring. The PiezoDrive focusing is similar to Nikon AF-S/Silent Wave or Canon USM, or Sony SSM, but not identical and on Sony models it can contrast-detect autofocus reliably. Sigma’s HSM hunts.

With Sigma facing patent claims by Nikon – that parts of their OS technology infringe on Nikon VR – Tamron VC is a mature system not so far challenged in the same way. It is also a very solid kind of stabilisation, free from swimming effects, and in this respect closely matches Sigma’s approach. Both are generally more comfortable than Canon’s IS which often seems to attach the image by a bungee cord to the viewfinder screen.

For video work, in-lens stabilisation is generally better than in-body as long as there is a good stable view which does not tend to float free when you pan slowly. For long lens work in general – over 200mm – in-lens stabilisation provides a view which is easier to aim and compose. We had already checked the lens out on Canon, with its smaller sensor area missing off the extreme corners (and therefore doing the lens favoured compared to other brands) but to compare with Sigma’s lens, needed to look at it in Sony mount.

The lack of VC in the Sony version of this lens is regrettable. There is no corresponding reduction in retail price.

Against this the Tamron has a longer zoom range, and it’s much smaller and lighter than the Sigma, taking regular 62mm filters not the unusual and large 72mm size. It also offers Piezo Drive focusing, which almost as quiet as SSM yet as fast as SAM. Small adjustments make a sort of faint clicking sound and focus travel is unusually fast, but a range of freehand refocusing tests using the Tamron showed that it is just as reliable in locking on to difficult targets as any other lens. Usually fast focusing means lots of overshooting or hunting, but not on the Alpha 580 used for this test.

Although the size and weight difference between this and the Sigma doesn’t look all that extreme when photographed in the studio, the heft in your hand (volume) is much less for the Tamron. It does not really seem any bigger than the Tamron/Sony 18-250mm design or the earlier 18-200mm.

The design of the lens follows these, with the LOCK switch for holding the lens at 18mm when walking round positioned for the right hand to operate, a long way from the AF/M switch (which should be used instead of the body switch for changing to manual focus).

This is a better design than the Sigma which clusters the AF/M, OS on/off and Lock controls together on the left hand side. Even after a year of use, both Shirley and I regularly turn the lens OS off, or turn AF off, instead of operating the Lock. All three controls move in the same way and are intended for the same fingers. Tamron’s location of Lock on the right hand side is ergonomically better.

However, both lenses fail to do the one simple thing which would improve such zooms – make the Lock control operate at ALL focal lengths not just 18mm. The Tamron is firm as we test it, so was the Sigma when new, but our Sigma can not now be used to pan with a plane or bird flying overhead unless one hand is used to keep the zoom from collapsing to 18mm immediately the lens is aimed upwards. To do the studio shot, the Sigma had to be taped to keep the zoom extended. Otherwise, it can’t even sit on a table set to 250mm.

You can’t see the sticky tape stopping the year-old Sigma zoom from deflating itself to 18mm every time when placed in the studio for this shot. The new Tamron is still young and firm. But we need locks which work at ALL settings.

It can not be difficult to devise a zoom lock which works at intermediate settings and it would transform the functionality of lenses like this.

Apart from ergonomics, there is no significant difference in build quality. Sigma feels more solid but heavier in action, Sigma’s exterior finish is difficult to clean and collects marks and dust easily. Tamron feels more plastic in build but has a high quality metal bayonet just like its rival.


Just studying the lens coatings shows why the Tamron can be more contrasty and less prone to flare in some light – especially if you fit a cheap filter to the Sigma and get contrast-eroding reflection for that front element.

The Tamron lens has visibly higher detail contrast than the Sigma, and in the centre of its field produces a very sharp image. The edge of the image lets it down, however, rather badly. The detail is soft at longer focal lengths unless stopped well down (ƒ/11 or so) and red-green chromatic fringes are serious enough to spoil JPEGs. They are not even very well corrected by using Adobe Lens Profile to process from raw (there is no Sony profile but Nikon, using similar sensors, can be selected).

This is a Sony Alpha 55 ISO 400shot, deliberately off centred in composition, with the Tamron set to f/9 (a good compromise between diffraction and stop-down sharpness) and 270mm.

The focus point is away from the centre of the image, and the lens displays good contrast and sharpness, but even here there is a slightly dirty look to the detail and chromatic fringes hit the white edge. This is NOT by the way anything to do with the Alpha 55 translucent mirror!

Here’s the edge of the shot at 270mm and f/9. I feel it would be almost unfair to Tamron to publish some of the worst results I got wide open. This is a defocused distance, of course, but this is also real-life imaging. This is why we did not switch from the bulky, heavy Sigma to the neater, lighter travel-friendly Tamron.

At full aperture and 270mm the performance is markedly inferior to the Sigma at 250mm wide open. The lens has better multicoating but poor field flatness, which creates the softening to the edges and corners.

The Tamron at 18mm has pretty strong barrel distortion which, when corrected using a lens profile in Adobe Camera Raw or Lightroom, lost some of the wide-angle coverage.

At wide to medium focal lengths, the difference is less marked and the Tamron is more equal the Sigma or other ‘best’ superzooms. But this is a lens bought for its extra reach at 270mm; given the performance, it’s not all that much use unless your subject is centred and surrounded by out of focus background.

Tamron at 270mm.

Sigma 250mm view – at near-infinity, the Tamron is longer the Sigma but not quite as much as 270mm would indicate.

Another issue is that of focal length, above and below examples. If the Sigma is a true 250mm (which it is not, all such zooms are shorter than their stated figures) then the Tamron is actually 265mm not 270mm at infinity.

This is unscientific, but the baby owl did not move and both lenses were placed in turn against the wire of its enclosure ensuring the same shooting distance to within a centimetre or so (with lens hoods removed). Tamron at 270mm.

By this distance, the Sigma at 250mm really is no different in focal length than the Tamron at 270mm, due to internal focusing differences. And it focuses closer than the Tamron for a larger maximum subject scale.

Although the close focus is good, at 49cm and 1:3.8 scale it’s not as good as the Sigma with 45cm and 1:3.4 scale – the true focal length at closer distances also seems to be shorter than the Sigma, though this is hard to evaluate.

As for bokeh, that’s not why you buy these lenses:

How many stumps? Wiry would be a fair bokeh description at medium apertures and longer focal lengths (270mm again, above, at f/9).

The Tamron PZD focus does work on the LA-EA1 Alpha adaptor for NEX; it’s not fast, but can lock autofocus perfectly even in difficult light. The Sigma can not do this at all and is not AF-compatible with the NEX adaptor. But… manually focused, the Sigma has OS. Vital!

Most telling is the weight difference when mounted on a light body like the A55. The Tamron is a far better match even if not as ‘good’ a lens – 970g for A55+Tamron, 1400g for A580+Sigma. Check prices, and work out your priorities.

– David & Shirley Kilpatrick

Tokina 11-16mm f/2.8 SD (IF) DX

TOKINA lenses – the brand name for optical giant Hoya’s interchangeable range – have always been renowned for their tank-like build quality and resistance to plastic trends. They compare so well with Nikon’s own lenses it is hard to tell the difference by feel, and the current design also matches Nikon more than it does Canon.
The latest news is that Tokina is to introduce the 11-16mm ƒ2.8 in Sony Alpha mount. Tokina stopped making Minolta mount lenses shortly before their parent company Hoya acquired Pentax. On October 28th 2010, Kenro UK announced availability. B&H has the lens in Sony fit here. Continue reading »

CZ 16-80mm Adobe Profile

Continuing to make profiles when time permits, here is a reasonably detailed profile for the Sony DT 16-80mm f/3.5-4.5 ZA Carl Zeiss zoom (2007) created using the Sony Alpha 550 14.2 megapixel camera using Manual Focus Check Live View at 14X to set the lens focus and ensure the chart is positioned to use 100% of the frame.
http://www.photoclubalpha.com/DSLR-A550 (DT 16-80mm F3.5-4.5 ZA) – RAW.lcp
Right click to download this 56Kb file which should be placed in the Lens Profiles/1.0/Sony folder of the directory on your computer which holds Adobe Lens Profiles.
This profile has been created at full aperture and f/8-f/11 depending on focal length, at 16mm, 24mm, 35mm, 50mm and 80mm focal lengths and involved 90 raw captures.
It is possible in ACR/Lightroom to use profiles which are not created on your own camera type. This profile can be applied to any APS-C Sony or Minolta camera using the 16-80mm lens; because the A550 is currently the highest resolution body, the CA data gathered is more accurate than would be possible using a lower resolution body but may need a saved adjustment in defaults. Individual lenses differ slightly and may also need adjustments.
I have checked the operation of the profile on files from A100, A700, A200, A380, A350 and A550 and it’s very effective in removing CA. Illumination is much improved at 80mm (notably). You may prefer to turn the geometric correction down to zero (off) when the angle of view matters more than perfect straight lines – and also, where people are in the shot near the edges at 16mm. The distortion of the lens is optimised to lessen ‘stretched faces’ at the ends and corners of the shot, applying the profile removes this slight barrel distortion and does not improve groups. It’s most useful for horizons, rooms, seascapes, and subjects where a good straight rendering is critical.
It has been suggest I should add a donation button for these profiles. By all means see our subscription page, there’s a downloadable PDF of the latest Photoworld magazine for $3. I could easily have zipped profiles and sold them in the same manner, but that is not why photoclubalpha is here; Adobe provide the software to do this free (OK, I know what the rest of their stuff cost me…) and profiles should be made public domain by creators.
– David Kilpatrick

HX1 Cyber-shot with EXMOR CMOS and G Lens

Press release from Sony, March 3rd 2009 – important bits highlighted in bold, uncalled-for comments in italics:
The Cyber-shot HX1 by Sony, teams stunning picture quality, lightning-fast shooting and powerful creative features in a stylish, supremely easy to use camera. The new flagship of the Cyber-shot range showcases a range of sophisticated image sensing, optical and processing technologies that offer unrivalled creative possibilities.

Continue reading »

Tamron 10-24mm f/3.5-4.5

Tamron’s new ultra wide angle zoom for APS-C/DX is getting a bit of a blasting from reviewers. Now, when I see this happen, I get curious. Lens testing is often badly designed for such zooms, involving test chart targets at distances which are extremely close and result in very bad figures caused mainly by a strong curvature of field (dished, ‘cap’ shape relative to the camera) when gets worse in effect the closer you focus.

Continue reading »

Tamron 70-300mm f/4-5.6 Tele-Macro LD Di

Our cover photo for the Spring 2008 issue of Photoworld was taken with a Tamron 70-300mm zoom costing less than £120 from most larger retailers or internet shops. The reputation of the lens meant we had to take a look at it, because the current choice in the Sony range is limited to one ‘kit’ 75-300mm costing £179, and the new 70-300mm G SSM lens costing £600.

Photoworld Spring 2008 cover

The Minolta 100-300mm f/4.5-5.6 APO (D) was one of the well-respected lenses not continued into the Sony line, possibly because it is thought to be a model designed for Minolta by Tokina just as the 100-400mm was. Sony part-owns Tamron, and Tokina is part of Hoya which now owns Pentax. Though all the lens makers source components and special types of glass from each other, the facilities which built the 100-300mm may not have been available when Sony took over.

The big question is why Sony did not opt for the 70-300mm f/4-5.6 Tamron Di lens instead of continuing the lower aperture 75-300mm. It would presumably have sold for about the same price in Sony guise.

The Tamron is a fairly unique design. It has a separate macro range, accessed by pushing a switch when you are between 180mm and 300mm zoom, and at minimum focus. You can not engage the macro range until you have these conditions met. Once you are in macro mode, the zoom is limited from 180-300mm, but the entire focus range is enabled from 0.95m to infinity with autofocus. It is a slow focusing lens and like other Tamrons with low gearing to drive the AF, appears to be very accurate on all the Dynax bodies.

This lens is of course suitable for film bodies, and unlike the new 70-300mm G SSM, it will work on models like the Dynax 9 unmodified, Dynax 800si, 7xi, 7000 and so on. Many owners have functioning film bodies of an older date and the move to SSM locks these out of AF functionality with all bodies prior to the 1999 Dynax 7.

This is a full aperture image detail – the bright reflected spots show how the aberrations surround or flare out from a sharp core image, which contains very fine detail – Alpha 350 original in-camera JPEG clip

The lens uses LD (Low Dispersion) elements, but it is not apochromatic and at full aperture displays some visible aberrations especially surrounding sharply focused light details. The image ‘core’ remains very crisp behind this veil of secondary imaging, and it only takes a little stopping down to tidy up the results. Our Bengal tiger cub (one of triplets born in the crocodile animal rescue park near Ingenio, Gran Canaria) was caught in movement, at full aperture, and despite the overlay of softness you can pick out eyelash-level detail on the 14.2 megapixel Alpha 350 image.

Here is the very next shot on the card – a 100 per cent clip of a zero sharpening, no NR, no processing ACR raw conversion from a shot taken fairly close to an alligator, f/9 and 130mm. The lack of colour fringes on the bright highlights is impressive.

Please remember what a 100 per cent clip from a non-sharpened 14 megapixel file actually is. Yes, I can make a 600 x 400 web image which looks sharper than this but making a 4952 x 3056 image at this sharpness with any USM – a five foot wide overall image at normal screen resolution – really tests any lens.

Zoom and apertures

You may have been reading the last article about kit zooms and note the graph showing that with cheaper lenses the aperture is likely to be cut early on in the zoom range. You might assume that £120-worth of Tamron would prove no different. You would be wrong, and this is one of the unique aspects of the lens.

The Tamron holds its maximum f/4 all the way from 70mm to 135mm, making it a full stop faster in this range than, for example, the 16-105mm SAL. It takes the same filter size and despite extending to 300mm, uses a single barrel tube and weighs only 435g. The aperture drops to f/4.5 between 135mm and 210mm. Even this is impressive; it’s as fast as the CZ 16-80mm at 80mm, all the way to 210mm.

Finally, at 210mm it does get cut to ƒ5 and it only becomes f/5.6 in the last 20mm of focal length, between 280mm and 300mm. The SAL 75-300mm becomes f/5 at 90mm andf/5.6 at just 125mm – the penalty for squeezing into a 55mm filter thread.

Even the SAL 70-300mm SSM G series lens is only f/4.5 from 70 to a mere 85mm, from then on it is f/5, and at 135mm it drops to f/5.6 all the way to 300mm. The Tamron is 2/3rds of a stop faster throughout most of its range on paper. In practice, we found that either f/5.6 on the Sony SSM is as fast as f/5 on the Tamron (due to coatings), or the Tamron is more optimistic in reporting its apertures!

Minimum focus

The Tamron 70-300mm manages a repro ratio of 1:2 – half life size on the sensor. That means a subject just 2″/50mm wide fills the entire frame (3″/75mm wide for full frame or film cameras). In Sony’s terminology, that is a 0.50X magnification at closest focus and 300mm setting. If you shoot macro on film right now, buying a digital body and this lens would give you the equivalent of your 1:1.5 mark on your macro lens.

No Sony or recent Minolta/KM zoom whether standard, tele or superzoom range offers better than 0.29X. It also stops down to a rather staggering f/45 at 300mm, not advised as sharpness suffers but potentially useful for macro work.

A comparison

We found the 70-300mm to be a fair match for our discontinued 100-300mm APO (D) overall. wider in aperture, and much better for small subjects. The 100-300mm’s repro ratio is just 0.25X, at 1.5m. It is f/4.5 as early as 120mm and f/5.6 from 150mm to 300mm.

Both lenses have solid metal mounts; both have eight contacts for full D specification; the 100-300mm doesn’t go down to 70mm, and it weighs 50g more.

The Tamron can be recommended as a bargain performer all round, ideal for anyone on a budget wanting a travel and general tele zoom with a very fast maximum aperture compared to other offerings.

– David Kilpatrick

The 70-300mm G SSM sized up

Today I took delivery of a Sony 70-300mm f/4.5-5.6 G SSM lens. There is no doubt this is the best built Sony SAL lens I’ve handled (the CZ 135mm 1.8, 85mm f1.4 are a class above again). It weighs over 800g with its lens-hood, which is one of the most efficient deep tele hoods I’ve seen. Continue reading »

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