Some new lenses


Anvh

Link Posted 05/07/2011 - 16:06
John what kind of focus did you use, the Phase AF or the contrast AF in live view?
I would suggest doing the later since you bypass all AF calibration errors with that.
Stefan


K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ

johnriley

Link Posted 05/07/2011 - 16:10
I agree, and that is what I have been using. After all, there's no hurry. However, also a manual check as well for each shot.
Best regards, John

Algernon

Link Posted 05/07/2011 - 17:01
I usually find when testing by photographing banknotes etc.
3 shots of every 4 are often out at say f/2. The sharpest is
often the one with the biggest file size MF is usually
the most reliable. I've never tried live view. I do use a 2x
Refconverter though. The Eye-Fi card also comes in handy,
because I can see the shot straight away.

I've posted this link before which explains the problems with
focus on lens tests:

Focus Fallibility: Lens Test Fallacies
http://www.slrgear.com/articles/focus/focus.htm
-
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi
Last Edited by Algernon on 05/07/2011 - 17:11

johnriley

Link Posted 05/07/2011 - 17:16
Consistency and care is always paramount in all experimentation, including the humble lens test.
Best regards, John

womble

Link Posted 05/07/2011 - 19:15
Back to the reviews issue. If you select something from the drop-down box to limit the reviews you see, you do not get what you expect. Thus, if you select 'all' you get nothing, and if you select 'lenses' you get only one of the two lens reviews.

K.
Kris Lockyear
It is an illusion that photos are made with the camera… they are made with the eye, heart and head. Henri Cartier-Bresson
Lots of film bodies, a couple of digital ones, too many lenses (mainly older glass) and a Horseman LE 5x4.

My website

johnriley

Link Posted 05/07/2011 - 19:26
It's early days yet for splitting the sections into Reviews and Articles - if you've found a glitch then a report to IT will enable them to look into it.
Best regards, John

johnriley

Link Posted 06/07/2011 - 09:01
The second of the Limited lens reviews is now up on EPZ:

http://www.ephotozine.com/article/smc-pentax-fa-43mm-f-1-9-limited-lens-review-1...
Best regards, John

Algernon

Link Posted 06/07/2011 - 11:00
The 43mm Ltd is the only Ltd I've got. I bought it back in the
film days and it's a superb lens. I've only used it a few times
on digital, mostly because I prefer zooms. It does perform well
on digital.

I'm surprised the MTF test shows the edges lagging so far behind the
centres? The corners of the building photos don't indicate any
problems at all with the corners at f/8.
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi

johnriley

Link Posted 06/07/2011 - 11:12
Without getting back to the same discussion as before, which, by the way, may well be an effect of spherical aberration due to de-centreing, the MTF results are what they are. Very often, lenses gain reputations but the lab results may or may not show something extraordinary.

At the end of the day lenses are for making images and MTF testing only shows a technical result. The 43mm has that extra "something" which gives the images a certain quality, a warmth of drawing and reproduction.

By comparison, the SMC Pentax-FA 50mm f1.4 I find generally "bland", the f1.7 is much better, but it may have very impressive MTF scores. I don't know about that, I haven't tested it in that way.

What I do know is that I would reach for the 43mm before the 50mm f1.4 without a doubt.

Of course this is what makes a lens test and interpretation of it so difficult, we can't ignore either the technical aspects or the creative emotional ones. It makes it very difficult for those not familiar with the technicalities.

At one time there was a fad for camera club members having their lenses tested and I recall Kevin MacDonnell recounting the tale of how Mr 96 lines per mm was so proud, sending Mr 80 lines per mm away, crushed.....

If we take the 43mm and use it to make images we should be very happy with it but, as Algi says, technically speaking the edges do lag markedly behind the centre.
Best regards, John

Don

Link Posted 06/07/2011 - 11:58
Algernon wrote:
I usually find when testing by photographing banknotes etc.
3 shots of every 4 are often out at say f/2. The sharpest is
often the one with the biggest file size MF is usually
the most reliable. I've never tried live view. I do use a 2x
Refconverter though. The Eye-Fi card also comes in handy,
because I can see the shot straight away.

I've posted this link before which explains the problems with
focus on lens tests:

Focus Fallibility: Lens Test Fallacies
http://www.slrgear.com/articles/focus/focus.htm
-

Pointless endeavour.
link
Fired many shots. Didn't kill anything.

Algernon

Link Posted 06/07/2011 - 12:06
Don, did you know that most editors won't open a photograph of
a bank note, at least not a British one. That's why it takes so
long to open images the software scans it first for banknotes
Obsolete notes no longer in circulation are probably OK.

The do make good tests as shown here: link
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi

Don

Link Posted 06/07/2011 - 12:12
Algernon wrote:
Don, did you know that most editors won't open a photograph of
a bank note, at least not a British one. That's why it takes so
long to open images the software scans it first for banknotes
Obsolete notes no longer in circulation are probably OK.

The do make good tests as shown here: link

never tried to be honest...lol!
Fired many shots. Didn't kill anything.

rparmar

Link Posted 06/07/2011 - 16:07
John, I agree with your summary of the characteristic lens rendering. Certainly I have never used a lens with as much "flair" (not "flare"!) as the FA43, though the FA77 comes close. Unfortunately none of the test photos included with the article demonstrate this.

I agree that arguing about small differences in test figures is pointless. There are far more important things. However, like others, I am a bit stunned by the low MTF50 measures since these are even lower than those I have seen before. For example, the very dependable Photozone found 1100 wide open, double the figure here. Already by f/2.8 the lens had tightened up nicely to around 2000, a score never even attained in your test.

I have done a lot of shooting with this lens, as it was the first lens I bought for my camera (after the kit). The Photozone results accord with my experience. I can use this lens for brick wall shots and get great results corner to corner at f/4. I do this not for testing purposes, but because I like finding cool street art.

There is no way in heaven the FA43 should consistently have half the border score of the FA31 and DA70. (Only wide open would I expect this number to be so poor.) My only conclusion is that there is in fact some issue with the test you did. This might be down to a bad sample since I am sure you followed procedure and took due care.

The other difference is the camera used. You use a K-5, I use a K20D and Photozone tested with a K10D. I cannot imagine this would matter so much, and if it did would not all three Limited lenses have skewed scores?
Listen to my albums free on BandCamp. Or visit my main website for links to photography, etc.
Last Edited by rparmar on 06/07/2011 - 16:11

johnriley

Link Posted 06/07/2011 - 16:32
The tests you mention cannot be compared, simply because we are measuring the total system, lens and body. That's why the update is interesting. The lenses are fine and perform better than the other lenses I have been testing in this total system.

Now this is of course a problem in that we can't make direct comparisons, but we only have to look at Boridar's site to see that. It's always been the same. Without a lab and aerial examination of the image there will be discrepancies between testers.

This often gets forgotten and I'm sure it leads to a lot of confusion, but the analysis is also in the review, as are my conclusions. These lenses were designed for film but they can still outperform some more recent offerings, and not others.

I can see that when we love a lens then seeing it doing less well than expected isn't very welcome, but it actually did very well indeed. There's nothing I can really add to the facts found.
Best regards, John

Sandehalynch

Link Posted 06/07/2011 - 17:12
johnriley wrote:
At the end of the day lenses are for making images and MTF testing only shows a technical result. The 43mm has that extra "something" which gives the images a certain quality, a warmth of drawing and reproduction.
...

Of course this is what makes a lens test and interpretation of it so difficult, we can't ignore either the technical aspects or the creative emotional ones.

The 'signature' as I think it's often referred to, the very individuality that allows one to choose a lens as a painter might choose a brush - hog, squirrel, or sable.

I've had my 43mm for eight years and it's never disappointed ...




though sometimes I'll be wanting to use a 1910 anastigmat triplet instead.
www.sandehalynch.com
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