FA Limited lenses

There's been a good deal of discussion about the three limited lens tests, unfortunately the results not meeting everyone's expectation. What I would say about that is that lens tests are done with a particular procedure, and it's the same for all of them. The first thing we need to do is believe the results and then analyse them with an open mind. If we take the "that can't be right the experiment must be faulty" point of view then we start to distort science to make it fit our beliefs.

So we find what we might expect to find - lenses that are designed for film have limitations technically when applied to digital, that we are close to the limit for APS-C sensors and film lenses but that some lenses are still good enough to hold their heads high and have other virtues that make them worthwhile.

In the case of the FA Limited lenses they are remarkably good.

The 31mm (46.5mm) I will be using as a standard lens. Lovely rendidtion, super quality, a really nice "feel"

The 43mm (64.5mm) is an odd focal length. I prefer it to the FA 50mm f1.4 and we may keep it for wedding portraits of couples, letting the 50mm move on. It's the first of the releases and the least suited to digital in some ways, but still a worthy lens.

The 77mm (115.5mm) is slightly longer than I've used for portraits, but still OK for that, performs better (just) than the 70mm Limited and is absolutely wonderful in terms of its rendition. This is my fravourite of the three and it will become my portrait lens.

The conclusion is that with the K-5 these lenses still retain qualities that justify their high price. In fact, of all of them the 77mm is a relative bargain and I'd snap that up if at all possible.

That being the case, it is little surprise that some lenses appear to under perform compared to expectations ...

A lens designed to be softer at wide apertures for portraiture is not going to compare favourably with a macro lens for instance, given the same test conditions.

As Disraeli once said, “There are three kinds of lies: lies, damned lies, and statistics”.

I recently read your ephotozine review of the 31mm John, and I was surprised that all of the sample images you posted are at f8 and f11. Was there any reason you decided not to test it at larger apertures?

I was curious about this too, however most of the sample images would benefit from the DoF provided by smaller apertures apart from the close portrait. I must say though that the lens in probably being limited by diffraction @ f/11, the optimum being between f/4-f/5.6

If I ever win the lottery I want one, in black, from the original batch assembled in Japan

John

I submit a selection of images to show general attributes and don't make the final selection. It can't be any more extensive as time and space available are predetermined. Further images and comments will continue here and other things can be covered, and that of course goes way beyond what tests and reviews normally give.

As for why f8 and f11, well probably conditions and the type of lens with those subjects. The idea was to cover as many subject types as possible, but I'm only asked for eight images, although I usually deliver at least 12 to select from.

Watch my EPZ portfolio and there will be many more examples over the coming weeks/months.

What strange editors they have at ephotozine This is the web, not print. There is no such thing as 'available space'. The page just gets longer!

To be honest I thought it was a glaring omission from the review. I think very few people are spending £1000 on a 31mm f1.8 lens to use it at f8 and f11.

Agree TIm, this is what many people are most interested in when they look at these lenses because getting good background separation and bokeh is more challenging on APSC, and immediately sets images apart from those taken on a good zoom lens stopped down.

Oh my, if you want open aperture there's an example in the 77mm review.

We need to realise that this is a review, not a lab test and there's a limit to what is done in the available time. There is also a practical limit in terms of space because if the reviews were all twice as long who is going to pay for all the time it would take in preparation? People are working to get these things on the web.

Different readers are interested in different things, so we should be thankful we have several reviews to look at and to aid us in our lens selection.

Not the words, John, no one expects you to write twice as much, but I can see no valid reason for not posting all 12 of your images.

I'm rapidly losing faith in any lens tests done with Imatest software.

The test done on the Pentax 16-45mm f/4 SMC DA ED AL shows the edge
almost as good as the centre at f/8 and 16mm link

The one for the Kit Lens actually show the edge better than the centre.
link

Later tests show poor edge performance for LTD lenses.

The DxO site actually has Zeiss lenses performing poorly?
(post link later).

Algi, you are misreading the information. So what is wrong with the 16-45mm showing excellent performance? It's an excellent lens. Gary doesn't give you the figures though, so you can't compare with later tests.

The kit lens results are also very good but nowhere do they suggest the edge is better than the centre.

The edges can be better than the centre at wide apertures though because of lens decentreing. This causes spherical aberration that reduces as the lens is stopped down.

Zeiss lenses can also perform poorly. Way back, I've just been looking at some wide aperture standard lens tests and the Noct-Nikkor wasn't as good in low light as the standard f1.2 Nikkor.

Throw preconceptions away, look at the facts. Those who doubt can always do their own testing and see for themselves, but bear in mind that samples of lenses vary as well. Lenses can be as much as 20% decentred and still give a good account of themselves, leaving us to wonder what they might achieve if they were put together right....

Well well well, losing faith etc?

I'm never impressed or amused as much as when some one condemns a product due to it not being perfect.

My present resentment approach to Pentax being only my POV.

Nothing in life is "just so".

Get a grip, use and prove and impress and be happy with your lot.

I did not discard (nor will) Pentax kit just because I use Nikon FF.

Every tool has a function and purpose.

For those that don't know......................

Pentax has a polished finish that others have yet to achieve.

Best regards.

Poor John, we're such a tough crowd!

Sorry John, not meaning to give you a hard time over this, especially as you didn't do this test, but this graphic actually shows at f/5.6 the edge is higher than the centre and this is on a wide angle zoom which normally has poor edges.
link Click on "Resolution at 18mm" Graph

There's no need to reply to that anymore than you have done, I'm just saying why I don't like Imatest.

Just for reference this is another (Imatest?) showing nearer to what I would expect from the Kit Lenses, although it's hard to accept that the edges are so bad. link

And just for reference (not much point in discussing Zeiss and Nikon here) this is the forum where they are unhappy with the DxO tests link

Pity the Paterson Lpmm chart won't work with Digital properly.

By a whisker, and that can easily mean slight decentreing just as well as a slight focus shift. I would say that's close enough to mean even coverage.

As regards the second test, why believe that one and not another one?

If the tests have been done with the Paterson chart, someone would be taking issue with the film/developer combination used.

If the images used instead were the Wellington on the Thames, then someone would eventually notice that boats actually move up and down with the flow of the water.

We have to have something, but it's only a guide and there's a lot of useful information in there. You've been given the full detailed charts in my reviews, so there's plenty of scope there if you know what to look for.