I was recently gifted a Pentax 135mm lens. That got me thinking!
Back in analogue days once you had got used to using the standard lens that came with your 35mm camera the next lens choice was either a wide angle or a medium telephoto lens. In the case of a medium telephoto lens the obvious choice was a 135mm and depending on budget either a f3.5 or a more expensive f2.8 aperture version.
Already in my collection of lenses was a Hoya 135mm f2.8 lens with a Nikon mount, hence with this lens, my newly acquired Pentax 135mm f3.5 and a Tamron 135mm f2.8 adaptall complete with Nikon mount, I ventured down to Eastbourne beach for a test session.
To test these three lenses I used my trusty and very battered Nikon FM, a Cosina C1 both loaded with Ilford Delta 100 black and white negative film. After all back in the days of analogue cameras both Mark and I would have taken quite a lot of black and white photographs. Metering performed using the ‘Sunny 16 rule’.
It was decided to add a little extra test to these lenses, namely. How would they perform on a digital camera body, to avoid the issue of several sensors producing different colour balances and contrast levels I used all three lenses on a Fuji XT-1 body with the relevant lens adapter. ISO was set at 200, daylight balance exposure via aperture priority. Images were recorded as RAF (RAW) files and converted to Jpeg (without adjustments) in Adobe Camera Raw.
Lens Specifications
Hoya 135mm f2.8
Construction: 5 elements in 4 groups
Aperture: 8 blades with a minimum aperture of f22
Filter size: 52mm
Built in lens hood
Weight: 400g
Tamron 135mm f2.8
Construction: 4 elements in 4 groups
Aperture: 6 blades with a minimum aperture of f22
Filter size: 55mm
Built in lens hood
Weight: 375g
Pentax 135mm f3.5
Construction: 5 elements in 5 groups
Aperture: 8 blades with a minimum aperture of f32
Filter size: 49mm
Built in lens hood
Weight: 270g
How the lenses handle
The Hoya is the heavyweight of the trio weighing in at 400g, although the Tamron is not that far behind at 375g. Focus on both the Hoya and Pentax still feel well damped despite their age, the Tamron focus action is a lot lighter but not overly loose. Both the Tamron and Pentax lens have half stop click steps whilst the ‘budget option Hoya has full stop steps only, although it is not a problem to set a mid stop aperture. All the lenses feel well balanced on both their relative film cameras or on the Fuji digital body. Another plus point with all three lenses is that they all come with a fitted slide out lens hood.
How the images were taken
The cameras were mounted on a tripod, focused manually on the centre of the pier (centre of frame) Film camera exposures were based as previously mentioned on the ‘Sunny 16 rule’, that is – bright sunny conditions, ISO 100, shutter speed 125th with an aperture of f16. Digital images were metered in aperture priority.
Conclusions
The Ilford Delta 100 film was processed in Ilfotec HC and the negatives scanned on a Plustek OptiFilm 7600i and the results viewed on a colour calibrated monitor along with the Jpegs from the Fuji XT-1.
Both the Hoya and Tamron lens show signs of fungus on their inner lens elements, the Tamron more so. This did not however appear to affect contrast or sharpness as much as expected.
When the black and white negatives were viewed- all three lenses were down on contrast and soft wide open at f2.8 with the edges displaying very obvious softness and a degree of vignetting.
Sharpness, contrast and evenness of exposure picked up once stopped down, optimum setting being f8 with all three lenses, there was a very slight dip in sharpness at f16. Once stopped down to f22 and f32 in the case of the Pentax lens sharpness had dropped to a noticeable level again, however contrast remained good.
At f2.8 Left to right Hoya, Tamron, Pentax
At f8 Left to right Hoya, Tamron, Pentax
At f22 Left to right Hoya, Tamron, Pentax
Edge sharpness at f2.8. Left to right Hoya, Tamron, Pentax
The digital files bore out the same results, however edges were not such an issue due to the cropped sensor in the Fuji XT-1. Strangely although all exposures were made in aperture priority, all the Hoya lens images well exposed, but both the Tamron and Pentax lenses returned darker but consistently exposed images. This is however not a major issue since exposure values can be corrected in Photoshop. More noticeable is the fact that there is a colour difference between all three lenses, again in isolation all are acceptable.
At f2.8 Left to right Hoya, Tamron, Pentax
At f8 Left to right Hoya, Tamron, Pentax
At f22 Left to right Hoya, Tamron, Pentax
Hoya 135mm at f8
An obvious bonus of a cropped sensor is that a 135mm lens becomes almost a 200mm equivalent lens.
A point worth mentioning is that whilst using an adapter to enable all three lenses to be fitted to the Fuji camera body; the infinity focus point shifts, this means – do not rely on the focus marks on the lenses, focus manually and carefully!
Final thoughts
Is it worth using an older manual 135mm lens?
The answer is – if you are happy to focus manually, then yes.
At one time manual lenses were almost being given away due to the lack of interest in film camera bodies but now many people have discovered or rediscovered the usefulness of older lenses since all three lenses can also be fitted to DSLR bodies albeit without autofocus and in some cases restricted metering modes, hence asking prices can sometimes be on the high side. There are some bargains still to be had out there though.
Give one a try.
Colin