Sigma AF 400mm f/5.6 APO (1988-1995) / Test and Sample Images

Sigma AF 400mm f/5.6 APO (1988-1995)
Test and Sample Images

Sigma AF 400mm f/5.6 APO Lens with Tamron-F 1.4XN MC4 mounted on a Nikon D90 (HS20EXR).

Sigma AF 400mm f/5.6 APO Lens Specifications / Performance Data

Construction:	11 Elements / 8 Groups
Focal Length:	400 [mm]
Maximum Aperture:	5.6
Minimum Aperture:	22.0
Field of View:	6° on FX / 4.3° on DX
Minimum Focus Distance:	4.0 [m]
Maximum Magnification:	1:9.5
Filter Size:	72 [mm]
Max Diameter:	85 [mm]
Length:	213.5 [mm]
Weight:	1.1 [kg]
Weight [D90 + MB-D80 + MC4]:	2.3 [kg]

The Sigma AF 400mm f/5.6 APO super-telephoto lens was introduced in 1988, and replaced in 1995 by the larger, and slightly better performing Sigma AF 400mm f/5.6 APO Macro DG series. This makes it a relic of the first generation of autofocus lenses. The lens is a sibling to the longer Sigma AF 500mm f/7.2 APO super-telephoto, and shorter Sigma AF 300mm f/4.0 APO telephoto lenses. More recently all of these lenses have been replaced by stabilised telephoto zoom lenses, with 400mm and 500mm maximum focal lengths. The only surviving offering for a mainstream DSLR body in this class is the highly regarded Canon EF 400mm f/5.6 USM L prime.

The attractions of these exotic relic super-telephoto prime lenses are in low cost for very good optical performance, simplicity, reliability, and importantly, low weight making them comfortable for handheld use in field conditions. The biggest drawback of these 18 to 25 year old lenses is in their typical condition, exacerbated by the known propensity for the styrene-polybutadiene “Zen” rubber surface coating to perish, become sticky, and in severe cases, separating from the surface and remaining on the user's fingers.

The sample I recently acquired was heavily discounted due to the coating being in the initial stages of breakdown, which required repeated application of an automotive compound for restoring aged rubber and vinyl trim to stabilise.

Given that the only robust review for this family of lenses covers the much newer Canon mount Sigma AF 400mm f/5.6 HSM APO macro variant, I thought that sharing my experiences would encourage others to give some of these exotic relics good homes.

The common claims that the newer macro variant of this lens is significantly better in optical performance appear to be overstatements, as test shots using a well calibrated D90 body produce results very similar in sharpness, contrast and chromatic aberration to the plethora of samples available on Flickr, produced by the newer macro variant. Moreover, test results produced by Photozone.de suggest >100 lines/mm peak centre sharpness at f/8.0, which is similar to published performance data for the professional grade manual Mamiya Sekor A 200mm f/2.8 APO and Sekor C 300mm f/5.6N ULD primes. Test shots using the Sigma AF 400mm f/5.6 APO yield similar sharpness and contrast to the Mamiya primes, using the same D90 body and test targets. The conclusion to be drawn is that a definitive comparison could only be produced by testing both Sigma primes on the same DSLR body, using a test rig and chart and proper analysis software, and importantly, ensuring that both lenses are representative samples, rather than unusually sharp or soft samples from the statistical extremities of the population.

An interesting observation is that the old and new variants show very low variations in sharpness between f/5.6 and f/11.0, making these easy lenses to use, unlike many primes with pronounced sharpness peaks, which force careful aperture management - the latter a common problem for inexperienced or amateur users.

Common complaints about the shaft driven autofocus being unusually slow are odd, since the autofocus speed is competitive against many other designs I have used, and better than some. Alleged problems with lock performance under low light conditions are no different than observed with other telephoto primes - some very sharp lenses will challenge some autofocus system designs. The only conditions under which autofocus acquisition and lock performance were marginal were under poor lighting, with a Tamron-F 1.4XN MC4 teleconverter.

Overall, this is a well behaved and easy to handle lens, with optical performance typical for lightweight professional grade telephoto primes. For a lens which typically retails between US$150 and US$200, that makes it a bargain for anybody prepared to handle the lens professionally, and not insisting on creature comforts like an internal focus motor and stabilisation, or zoom capability.

Additional testing, during September, 2013, using the Nikon D800 is detailed in Annex A. Further testing in January, 2014, using the Nikon D7100 is detailed in Annex B.

References:

Sigma History - 1961 to present day, Sigma Corporation, 04 September 2005, URI: http://www.sigmauser.co.uk/index.php?option=com_content&view=article&id=51&Itemid=67
Lynne Barber, SIGMA AF TELE-400MM F/5.6, Amateur Photographer, 4th April, 1987, URI: http://www.sigmauser.co.uk/images/stories/museum/APReview40056AF.pdf
Sigma AF 400mm f/5.6 HSM APO macro - Review / Test Report, Lens Reviews - Canon EOS (APS-C), Photozone.de Website, URI: http://www.photozone.de/Reviews/306-sigma-af-400mm-f56-hsm-apo-macro-test-report--review
Sigma AF 400mm f5.6 Group, Flickr.com, URI: http://www.flickr.com/groups/613292@N24/pool/with/3515942165/
Sigma 400mm f/5.6 APO Lens Sample Photos, Pbase.com, URI: http://www.pbase.com/cameras/sigma/400_56_apo

Annex A Sigma AF 400mm f/5.6 APO / Nikon D800 DSLR Tests

Annex B Sigma AF 400mm f/5.6 APO / Nikon D7100 DSLR Tests

Annex C Sigma AF 100-300mm f/4 EX IF HSM APO / D7100 Comparative Test

Sigma AF 400mm f/5.6 APO Lens mounted on a Nikon D90 (HS20EXR).

Sigma AF 400mm f/5.6 APO Sharpness / D90 Contrast Tests

Comparative sharpness test for progressively decreasing apertures, from wide open at f/5.6 down to f/13.0. Above, full size sample, below 1:1 crops, viewed in Aperture 3. The loss of sharpness between f/5.6 and f/13.0 is not pronounced.

Comparative contrast test for Mamiya Sekor C 300mm f/5.6N ULD (upper left), Sigma AF 400mm f/5.6 APO (upper right), and Sigma AF 400mm f/5.6 APO with Tamron 1.4XN MC4 Teleconverter (below). The contrast performance of the Sigma AF 400mm f/5.6 APO is very close to the Mamiya Sekor C 300mm f/5.6N ULD, and sharpness is also comparable - it is like the Mamiya a genuine professional grade lens both in construction and optical performance. The impact of the 1.4XN teleconverter is not as severe as might be expected, although there is some loss in contrast, sharpness, and chromatic aberration performance, but not enough to seriously compromise lens utility.

Comparative contrast test for Sigma AF 105mm f/2.8 DG EX Macro @ f/8.0 (upper left), Mamiya Sekor C 300mm f/5.6N ULD @ f/5.6 (upper right), Sigma AF 400mm f/5.6 APO (lower left), and Sigma AF 400mm f/5.6 APO with Tamron 1.4XN MC4 Teleconverter (lower right). Results are comparable to the preceding test, noting that the Sigma 105mm f/2.8 lens produces very high contrast.

Comparative sharpness test with Tamron-F 1.4XN MC4 teleconverter for progressively decreasing apertures, from wide open at f/5.6 down to f/11.0. Above, full size sample, below 1:1 crops, viewed in Aperture 3. The loss of sharpness between f/5.6 and f/11.0 is also not pronounced, but chromatic aberration is slightly increased. Contrast is reduced, and sensor noise increased due to the ~1 EV of reduced transmission.

Comparative sharpness test with Tamron-F 1.4XN MC4 teleconverter for progressively decreasing apertures, from wide open at f/5.6 down to f/13.0. Above, full size sample, below 1:1 crops, viewed in Aperture 3. The loss of sharpness between f/5.6 and f/13.0 is also not pronounced, but chromatic aberration is slightly increased. Contrast is reduced, and sensor noise increased due to the ~1 EV of reduced transmission.

Sigma AF 400mm f/5.6 APO / LP III Monopod

Focal Length: 400mm [eq. 600mm in FX]
Aperture: f/5.6 - f/8.0
ISO: Auto Nikon Control Law
Shutter: Auto Nikon Control Law
Metadata: EXIF, IPTC
Notes: some images have highlight overexposure corrections with Aperture 3

Sigma AF 400mm f/5.6 APO Handheld

Focal Length: 400mm [eq. 600mm in FX]
Aperture: f/5.6 - f/11.0
ISO: Auto Nikon Control Law
Shutter: Auto Nikon Control Law
Metadata: EXIF, IPTC

Notes: some images have highlight overexposure corrections with Aperture 3; multiple images corrected for contrast.

Sigma AF 400mm f/5.6 APO / Tamron-F 1.4XN MC4 / LP III Monopod

Focal Length: 560mm [eq. 840mm in FX]
Aperture: f/5.6 eq. f/8.0
ISO: Auto Nikon Control Law
Shutter: Auto Nikon Control Law
Metadata: EXIF, IPTC
Notes: detail crops are 1:1 768^2 pixels for comparison; highlight overexposure corrections with Aperture 3; one image corrected for contrast.

[Contrast adjusted in this image]

Sigma AF 400mm f/5.6 APO / Tamron-F 1.4XN MC4 Handheld

Focal Length: 560mm [eq. 840mm in FX]
Aperture: f/5.6 - f/8.0 eq. f/8.0 - f/11.0
ISO: Auto Nikon Control Law
Shutter: Auto Nikon Control Law
Metadata: EXIF, IPTC

Notes: some images have highlight overexposure corrections with Aperture 3; multiple images corrected for contrast.

Note: If you wish to view EXIF metadata in the DSLR images, the simplest solution is the FxIF Firefox extension. Please note that the focal length and aperture settings in the EXIF data reflect the configuration of the lens, regardless of whether a teleconverter is attached. This is because the teleconverter passes digital messaging from the lens without decoding and regenerating it.