ACR/LR Profile for A900+MinRS 24-85mm

Although it’s far from a perfect lens, this small 1999 Minolta RS optic is my favourite for general travel and everyday use on the Alpha 900. It is a convenient size and weight, performs well when stopped down a little, and has exactly the range and minimum focus I need.

Mouseover image to see effect of this profile used on a shot taken at 70mm focal length.
The profile created for ACR6/LR3 is at four focal lengths – 24, 35, 55, 85 – and two apertures, wide open and f/9. The chart distance ranges from about 120cm to about 4m.
To download:
http://www.photoclubalpha.com/DSLR-A900 (24-85mm F3.5-4.5) – RAW.lcp
Right click and save. Correction of CA and distortion is pretty good, and this profile identifies itself correctly as a Minolta lens. It should be placed in the Sony directory of Adobe Application Support>Camera Raw>Lens Profiles.
– David Kilpatrick


Adobe Lens Profile for 16mm f/2.8 NEX

I have made a simple (f/2.8 and f/8 chart set) Adobe Lens Profile for the 16mm f/2.8 NEX E-series pancake lens. It seems to work well for closer distances, because that’s how it had to be made; CA is reasonably well corrected, vignetting is eliminated, and distortion of closer lines – maybe if you are looking through a door frame, etc – is very accurate. The profile was created using NEX-5 and 16mm.
You can get this profile here:
http://www.photoclubalpha.com/Sony NEX-5 (Sony E 16mm F2.8) – RAW.lcp
Right click to download/save the target file, and install this in:
Library>Application Support>Adobe>Camera Raw>Lens Profiles>Sony

Uncorrected 16mm shot

Using Adobe Camera Raw 6.2 RC with the profile active at default settings
JPEG profile added (17/08/10)
I have now added a JPEG profile from the same set of images as the raw – this is lucky, I didn’t think people would need a JPEG profile but happened to have the camera set to RAW+JPEG when the test shots were made, and this has been requested for those using HDR or other JPEG-only modes.
http://www.photoclubalpha.com/NEX-5 16mm JPEG.lcp

Above: HDR three-shot with 16mm, straight JPEG

HDR shot opened in Camera Raw without adjustments, but with the Profile enabled
Using the profiles
A full Adobe Profile is undertaken at several focus distances, apertures and zoom settings (or for prime lenses, just at a range of distances and apertures). The largest chart I can print is A2+ using the Epson 3800, and with a 24mm equivalent lens, this means having the camera surprisingly close to the target. The profile is therefore only 100% correct for subjects at 115cm from the camera, which corresponds to the 4X minimum focus distance suggested by Adobe.
I have found from using the 16mm that its optimum aperture for central sharpness is probably f/5.6, and that chromatic aberration and vignetting do not improve at stops smaller than f/8. There is a slight improvement in detail sharpness in the extreme corners at f/11 and f/16, but this is due to extra depth of field helping to cover a curved focus field. I therefore made test sets at f/2.8 and f/8 for this profile.
The geometric distortion is most visible with closer subjects such as the subject above (The Slave Girl, a bronze c. 1870 by John Bell, at Cragside House in Northumberland). This is a hand-held exposure of 1/4 at f/8, and is perfectly sharp despite the lack of stabilisation; every word of the interpretation can be read at 100%. I have found most shots are perfectly sharp with the 16mm given reasonable care, as you would take with a Leica, to breathe correctly and make a shake-free exposure. This is not the case with SLRs where the mirror action nearly always causes shake.
For more distant subjects, the 100% default setting of the ACR/LR Lens Correction panel can be reduced and where there are few straight lens removed entirely to secure the maximum field of view. Similarly, the vignetting correction can be reduced or removed entirely as the natural darkening towards the corners with this lens is attractive.
Although this profile is named to match perfectly the naming convention used by Adobe for the 18-55mm, I find that ACR 6.2 can not be relied on to use it for Auto as a default (if you work with more than one lens, Adobe Lens Correction soon proves unpredictable in this anyway). If you select Auto, then select Sony, the lens profile will be selected but the Auto button changes to Custom. If you then save new Lens Correction Defaults, or Camera Raw Defaults, ACR will attempt to force this profile on the 18-55mm and the reverse will also happen. So it’s necessary to check which profile is selected. Using ‘Previous Conversion’ for shots taken on the same lens is a quick way to get there.
The additional Manual Controls can be used on top of the profile (the second tab of the interface). The most useful are the geometric distortion (camera angle) corrections. The Chromatic Aberration/Colour Fringe controls can be fine tuned as the correction for CA while very effective relates only to the tested focus distance. CA may change with focus but my particular lens doesn’t seem to suffer from this. All that is necessary is to enable Defringe All edges as a default, and this will remove any hint of colour remaining. As a tip, setting Colour Noise Reduction to a high value can help remove CA and purple fringes in many shots processed through ACR/LR. The colour NR detects 1-2 pixel fringes just the same way it detects individual pixels, and neutralises much as it does noise.
– David Kilpatrick


Fitting a Vectis 80-240mm to the NEX

OVER the past few days I’ve been looking at the NEX-5 and a range of lenses and optical systems. I’ve got adaptors for C-mount (16mm/TV/CCTV) lenses, Leica 39mm screw, Minolta MD and the LA-EA1 for Alpha A-mount. The NEX-5 has proved able to provide a surprisingly bright focusing image through a classic German microscope:

It also proved very competent with the Sigma 70-300mm f/4-5.6 OS lens, the adaptor providing power for the OS which is fully functional, and also for auto exposure, leaving only manual magnified focusing to tackle. Continue reading »

The tortoise and the hares?

SONY has shown itself to be lagging behind the competition as we reach the third bend on the second lap of the development of HD-video capable DSLRs. At PMA 2010, nothing ‘real’ was shown and the closest they came to further launches in the Alpha range was an advanced pre-production prototype of a 24mm f/2 Carl Zeiss T* ZA SSM.
But Sony may prove yet to be the tortoise – or perhaps to be Brer Rabbit. They could make the finishing line, the goal of a truly useful video DSLR, before Nikon/Canon/Pentax/OlySamPanny get there.
Continue reading »

Alpha 850 official press release

Sony has announced the Alpha 850 today, without a press conference, but via email to editors. The press release follows, confirming pretty much everything we have already been able to reveal about the 850. One exception – it does have dual BIONZ processor, not single, just a slower image throughput perhaps due to clock speed, buffer, processing firmware changes. We must hope that the slower capture rate is accompanied by superior image quality, as that is a real possibility. I have marked in bold any phrases which I think might indicate something new. Apparently the body-only deal is to appear one month before the kit.
Continue reading »

Sigma 18-250mm f/3.5-6.3 DC OS HSM

Tamron’s 18-250mm lens – later adopted by Sony – was so good that it really takes some effort to beat it. Sigma has put that effort in, but the cost is a very much larger and heavier lens. If all you got was some better performance, it might not be all that exciting. But you get potentially superior anti-shake through its built-in OS, and faster focusing with HSM, the Sigma equivalent of SSM. And you can buy it for under $430, and it works fine on the NEX A-mount adaptor for stabilised videos too – with some degree of autofocus tracking during filming.
Continue reading »

Crop or cram? Pixel density versus the big view…

The Alpha 900 offers an unrivalled view through its 100% prism finder. The extra brightness, as well as the size and clarity, make most subjects far easier to photograph well. For some users, however, the full frame camera brings a disadvantage in terms of reach and resolution. You need lenses 50% longer (and thus twice the size, and four times the cost!) to fill the frame with the same distant sports and wildlife subjects. I don’t need to remind anyone how popular these two subjects are with amateurs, and sometimes, how important to professionals.
Continue reading »

The Sony Alpha 380 – review

My Sony Alpha 380 was supposed to arrive before July 13th according to SimplyElectronics.net – via Amazon – claiming UK despatch of 2-10 days delivery after debiting my card on July 6th from a July 3rd order. Well, it didn’t arrive by July 21st, and after some email exchanges I have apparently obtained a refund for the charge they made for an item they did not have (though this was still showing as ‘processing’ in August). Warehouseexpress.com had got the A380 plus 18-55mm kits  by that time, for £10 less, and delivered in 24 hours. Update August 9th: under a month later, the warehouseexpress kit price has fallen by 10% (£50) to £548 inc VAT.
Continue reading »

1 3 4 5 6 7 9