alpha mount future - question for DK

[David Kilpatrick]

Yes, I saw that. Of course I was replying to a question about whether it was worth buying Alpha mount lenses right now or waiting, and my answer was wait, because the likelihood of revisions with photokina round the corner and NEX just launched is considerable.

I do not appreciate being quoted entirely out of context, but there's nothing I can do about it. The quoter should have referenced the entire thread and provided a link, not clipped text without any surrounding context.

David

[pakodominguez]

I do not appreciate being quoted entirely out of context, but there's nothing I can do about it. The quoter should have referenced the entire thread and provided a link, not clipped text without any surrounding context.

It is hard to be a celebrity in the Alpha world...

Nah, as usual, you have a guy in the need to be popular an use any resource in order to get there -specially if he knows you won't go to that forum explain what you really meant.

[catalytic]

Two other lenses which must be revised are the 11-18mm (replaced with a 10-24mm SAM)

Gulp. Oh no, not a rebadged Tamron 10-24? Say it ain't so! I don't think i've read one positive review of that lens yet (not that the 11-18 was brilliant either, but at least it was generally considered to be a decent lens)

[David Kilpatrick]

No guarantee of the 10-24mm, Sony might just develop something of their own. But it is the most logical lens to be dressed in Sony livery at photokina. Sure, I don't like it much, but I doubt the 11-18mm will be given in-lens motor focusing.

David

[catalytic]

Hopefully, Sony will specify an enhanced design of the 10-24 like Nikon did with their version of the Tamron 10-24/3.5-4.5 (AFAIK, the Nikkor AF-S 10-24/3.5-4.5G is a rebadged Tamron 10-24 that has been tweaked to Nikon's specs). I wonder if Sony can actually use the same design as Nikon (maybe it's a "premium OEM design option" Tamron makes available to the camera companies) or if it's exclusive to Nikon?

If you compare the lens design and specs of the Nikon and Tamron 10-24, they appear to be based on the SAME base lens design and construction, but the Nikon design has 14 elements in 9 groups (3 asph, 2 ED) instead of Tamron's 12 elements in 9 groups (4 asph, 2 ED).

Tamron 10-24 Lens Construction:
http://www.tamron.co.jp/en/lineup/b001/structure.html

Nikon 10-24 Lens Construction (scroll towards bottom):
http://www.nikon-image.com/products/len ... 45g_ed.htm

The specs are remarkably similar as well:

MFD: 0.24 m for both the Tamron and the Nikon
Length: 86.5 mm for the Tamron vs 87 mm for the Nikon
Diameter: 83.2 mm for the Tamron vs 82.5 mm for the Nikon

Tamron 10-24 Specs:
http://www.tamron.co.jp/en/lineup/b001/spec.html

Nikon 10-24 Specs:
http://www.nikon-image.com/products/len ... 45g_ed.htm

[David Kilpatrick]

Hopefully, Sony will specify an enhanced design of the 10-24 like Nikon did with their version of the Tamron 10-24/3.5-4.5 (AFAIK, the Nikkor AF-S 10-24/3.5-4.5G is a rebadged Tamron 10-24 that has been tweaked to Nikon's specs).

Entirely different - they look superficially similar, but a completely different focus and zoom arrangement applies, one has a rear zoom ring and front focus, the other has the reverse. I have used both and there is no comparison in design and performance, even though they are similar in specifications and size.

All retrofocus wide angle zooms are more or less based on a common design. Nikon does not use any hybrid aspherical elements - that's a Minolta technology bought by Tamron.

David

[Argonaut]

Me, I'm already using various stitching programs to make wide-angle shots. This method gives you whatever wide angle lens equivalent you want. I fully expect to see more in-camera panorama software (let's start a pool on the date of the first implementation that allows 'painting' multiple passes instead of just one). I mean, wouldn't you rather use your sharpest, best lens in a stitch than spend a Grover on a less-than-best wideangle?

[catalytic]

Entirely different - they look superficially similar, but a completely different focus and zoom arrangement applies, one has a rear zoom ring and front focus, the other has the reverse. I have used both and there is no comparison in design and performance, even though they are similar in specifications and size. [...] All retrofocus wide angle zooms are more or less based on a common design.

Definitely the performance is significantly better on the Nikkor and the zoom / focus cam control is arranged differently, but there is so much similarity in the specs that it strikes me as more than superficial and beyond simple coincidence. To wit:

Focal Length: 10-24 vs 10-24
Max Aperture: f/3.5-4.5 vs f/3.5-4.5
MFD: 0.24 m vs 0.24 m
Length: 87 mm vs 87 mm
Diameter: 83 mm vs 83 mm



Sure, retro-focus WA designs are often similar, but if you compare any two other WA zooms on the market (except for the Tamron 11-18 vs Sony 11-18, which are obviously the same lens), no two lenses are this much alike in so many parameters, right down to the millimeter! Admittedly, this could just be happy coincidence, and i really have no evidence to back up my assertion other than the above similarities, but one would have to admit that this degree of similarity between two completely different lenses would be quite rare and unusual.

Nikon does not use any hybrid aspherical elements - that's a Minolta technology bought by Tamron.David

Granted, this was true back in the 80's, but Nikon started using hybrid aspherics to remain cost-competitive in their midrange zooms in the 90's (28-70/3.5-4.5, 35-105/3.5-4.5, 28-105/3.5-4.5, 28-200, 24-85/2.8-4). Going forward, they extended the use of hybrid aspherics to most of their (non-high-end) zooms that use aspherics. Heck, even the expensive 14/2.8 uses hybrid aspherics.

They aren't doing it much these days, but 5-10 years ago, they specifically called out the use of precision glass aspheric (PGM) elements in their mid-high-end lenses as a feature. We Nikon users assumed that if Nikon didn't specifically cite the aspheric elements as being PGM, they were probably hybrid.

From the Nikon website:
"PAG (Plastics on Aspherical Glass) hybrid lenses

The term Plastics on Aspherical Glass, or PAG, generally refers to the method used to fabricate hybrid aspherical lenses combining glass and plastic.

UV-curable resin is injected between the spherical glass lens and the aspherical metal mould, then irradiated with UV light to form hybrid lenses. Nikon has developed its own plastics and moulding technology for PAG, and now manufactures large-diameter, high-precision lenses with large aspherical lens surfaces in volume and at low cost."

http://help.nikon.ca/app/answers/detail ... technology

Do you think it's possible that Nikon either licensed this technology as well or uses Tamron as an OEM for some of their lenses? I know they used Cosina to manufacture some of their lenses in the past...

[David Kilpatrick]

If you look hard at the schematics, the lenses are really very different. Tamron use the term hybrid aspheric, which is a Minolta term; Nikon does not, clearly they have not licenced from Minolta, and have their own patent. I think the Nikon 10-24mm uses moulded glass aspheric elements.

I think Nikon may well use Tamron for some lenses (the 14mm f/2.8 might be an instance worth examing more closely) and all the major makers used just about everyone for their wide-to-tele and kit type zooms in the 80s/90s. Minolta bought off the shelf designs from Hoya/Tokina and Cosina, and for the MD system sourced a well-known 28-70mm kit lens which didn't look or feel like a real Rokkor. It happened to be rather better optically than any previous 'genuine' Minolta which embarrassed them.

One of the problems with all of this is that while Minolta was the first to develop and use hybrid aspherics, their production plant was not necessarily made by their own engineers. Nikon supplies machinery to the optical industry and could even have made the system which formed Minolta's hybrid lenses.

David

[catalytic]

David, alas, without anything concrete to go on, i'll have to defer to your expertise here...

I do, however, want to ask you how it might occur that these two lenses have the same dimensions down to the millimeter? Could it be that the optimization software that they use came up with very similar results when simulating 10-24/3.5-4.5 lens designs? And would you say that for any given focal length or focal length range and max aperture spec, lenses from most manufacturers would by necessity end up at roughly the same dimensions because that is what gives the optimal results in the simulation programs?

Or, to put it another way, for any given lens design, focal length range, and aperture spec, there is an optimum set of parameters. And to use different parameters would be silly because it would be suboptimal in some way? Therefore, can one assume that most lens design teams would end up at the same result if the constraints were the same, and that most lenses on the market in the same price class should be roughly the same in optical potential, with the differences mainly being down to decisions made in the design process on how certain parameters are prioritized and the constraints imposed on the specific design (cost vs size vs mechanical build quality vs optical performance wide-open vs smoothness of bokeh, etc)?

What are your thoughts?

[David Kilpatrick]

The design down to millimetre is not particularly unusual, as most lenses now use a common range of filter sizes. Therefore a 77mm front thread is common and this in turn dictates the lens hood bayonet, which is now sufficiently matched between makes for Chinese copy hoods to appear which fit several brands. As for the length, I do believe Tamron quote Nikon lens fit dimensions always, but some makers quote Canon fit and as the back focus is different that means lenses can actually be the same size but appear different.

I have had the Tamron and the Nikon side by side, here, used them both at the same time. I got them because I thought - that Nikon is just a Tamron! The moment I got them together, and handled them together, it was obvious the Nikon is not just a Tamron and the resemblance is coincidental - or, as you suggest, a result of using similar design software.

Tamron has a current project to make its lenses match Nikon visually. They have said this. Take a look at pix of the Nikon 85mm macro and the Tamron 60mm macro. Gold rings and typefaces apart, Tamron is copying Nikon's current look.

David

[catalytic]

Interesting. Did they say why they wanted to copy the Nikon look specifically? And why not Canon or Sony, for example? Canon has more market share than Nikon, and Sony is practically part of the same family...

[David Kilpatrick]

They never mentioned the name Nikon. They simply have said - this is our new look, it is designed to fit in with the industry standard. Since it is very closely modelled on Nikon, that's obviously who they consider to be the standard.

Canon lenses all look different anyway, there is no consistency in design. But the latest ones actually have a grip very similar to Nikon, and Tamron, and not like Sigma, Sony or others.

canonzoomset-web.jpg (110.58 KiB) Viewed 5593 times

Notice in this trio of current Canon zooms how wildcard the design details are - the graphics (lettering), the way the barrel components are finished at their ends, etc. There is a superficial use of similar grip rubber but sometimes they forget and change the grip, to give tactile clues about zoom and focus rings. Also, these three lenses all FEEL totally different and have three different types of motor - true ring USM, clunky USM and micromotor.

David

[bfitzgerald]

Leaving aside the grips and design etc..that 15-85mm is said to be a very nice lens.

[David Kilpatrick]

The 15-85mm is excellent, and should be for around £700. The 18-200mm is pretty mediocre. The 18-135mm is a basic lens - no USM, much lower price - but actually performs very well optically. Also, it has IS which is optimised better for video.

David