Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
08-02-2008, 03:30 AM   #1
Veteran Member
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,863
Sharpest lens, any brand, ever?

I am on the research of the sharpest lens. Focal length and make don't matter. I am only interested in center resolution.

I am asking because such a lens is the delimiting factor for achievable macro magnification using a macro coupler ring.

According to photozone.de, the three top performers for the K mount are:

FA 31/1.8 Ltd.: 2345/2244.5
FA 43 Ltd: 2422/2311.5
Sigma 30/1.4: 2453/2271

(figures are LW/PH at f/4 and f/2.8, resp.)

Of course, with a macro coupler, the mount doesn't matter.

Canon mount: (K-correction factor to Pentax K: 1.1587)
Sigma 30/1.4: 2117/2036.5
Sigma 30/1.4: 2453/2360 (K-corrected)
Canon 24/1.4 L: 2174.5/2173
Canon 24/1.4 L: 2519.5/2518 (K-corrected)
Zeiss 85/1.4: 2080/1985.5
Zeiss 85/1.4: 2410/2300.5 (K-corrected)

Nikon mount: (K-correction factor to Pentax K: 1.052)
Zeiss 85/1.4: 2291/2258
Zeiss 85/1.4: 2410/2375.5 (K-corrected)
Zeiss 50/1.4: 2319/2230
Zeiss 50/1.4: 2439.5/2346 (K-corrected)
Zeiss 35/2: 2321.5/2336.5
Zeiss 35/2: 2442/2458 (K-corrected)
Zeiss 25/2.8: 2325.5/ 2147.5
Nikkor 14/2.8: 2243/2107.5

So, the absolute top performers are easily recognizable by a resolution which is higher at f/2.8 than at f/4 (the latter being already diffraction-limited for those best of the best).

I.e., the Canon 24/1.4 L and probably best in this list, the Zeiss 35/2. The Zeiss 21mm is famous but not in the photozone test database.

With a Zeiss lens which are said to resolve about 300 lp/mm, features as small as
1.6 microns should resolvable. To reach the limit (0.55 microns), one needs a 900 lp/mm lens, i.e., a lens with optimum performance at f/1.0.

So, are there any better lenses out there? Maybe, for the FourThirds system? Or a high-quality P&S?

(they then have to be short focal and with a small image circle for physical reasons)

08-02-2008, 04:09 AM   #2
Veteran Member
Asahiflex's Avatar

Join Date: Jan 2008
Location: Netherlands
Photos: Gallery
Posts: 2,754
QuoteOriginally posted by falconeye Quote
So, are there any better lenses out there? Maybe, for the FourThirds system? Or a high-quality P&S?

(they then have to be short focal and with a small image circle for physical reasons)
You should really look into the 50mm Pentax Macro lenses, such as the SMC Pentax-F 50mm f/2.8 and also the FA version. Those are among the sharpest lenses ever made.

Just look at the resolution figures by made by Yoshihiko Takinami, he has tested quite a few Pentax lenses.

http://www.takinami.com/yoshihiko/photo/lens_test/
08-02-2008, 04:46 AM   #3
Veteran Member
rparmar's Avatar

Join Date: Jan 2008
Photos: Gallery
Posts: 8,783
I am a little confused by your methodology.

1. Since the best lenses will for some time out-resolve sensors, I am not sure why "the ultimate" is required.

2. For your application I am not sure you can base your decision on tests, since no-one does these in the macro range -- aren't MTFs done at infinity focus?

3. You specify values at f/4 and f/2.8, but this will give you practically no depth of field in a macro situation. Shouldn't you be looking at f/11 or more?

I am sure many besides me will recommend the Vivitar Series 1 105mm for macro use.
08-02-2008, 05:08 AM   #4
Banned




Join Date: Oct 2007
Location: Savannah, U.S./Baguio City, P.H.
Posts: 5,979
QuoteQuote:
. You specify values at f/4 and f/2.8, but this will give you practically no depth of field in a macro situation. Shouldn't you be looking at f/11 or more?

you absolutely should which makes this whole thing rather bunk to be honest because at f11 what lens isn't sharp? I typically use f8 to f16 when doing macro work with my bellows using an smc-M 50mm 1.7 if I tried using anything higher than f8 the DOF is so thin that even on a tripod its hard to get focus, forget about it hand held. I dont understand the point in this, anything I'm missing?

08-02-2008, 05:32 AM   #5
Veteran Member
Nesster's Avatar

Join Date: Oct 2006
Location: NJ USA
Photos: Gallery
Posts: 13,047
Also, the resolution numbers aren't directly comparable between cameras, so the Canon numbers won't match Pentax, and neither will match Nikon, and so forth. I see you applied some sort of correction factor, maybe that helps.

Further, due to testing methodologies, a difference of some percentage in the lines measurement represents false accuracy. Consider: the actual focus in a test needs to be different by a fraction of a mm and the numbers are different (ie. edge numbers may go up while center goes down).

Plus given lens sample variation - and again we're talking fractions of a mm - several samples would need to be statistically analyzed to give 'indicative' performance for a given lens model. Not to mention camera body variation - your body probably won't be precisely the same as the body used in testing, even if it is the same model.

And then the one you end up may be on either side of the bell curve.

All that being said, unfortunately if you're looking for the ultimate example for yourself, the usefulness of the tests is to get you a short list of possibilities. You then have to keep buying them, testing and discarding (selling off) the losers, until you've found the one with sufficient characteristics for you.
08-02-2008, 06:28 AM   #6
Veteran Member
jsherman999's Avatar

Join Date: Dec 2007
Photos: Gallery
Posts: 8,228
.

To summarize what others have said, you can save yourself a whole lotta headache
by picking up a Viv 105, FA 50 2.8, DA 35ltd, Sigma 70/105/180, Tamron 90, VL 125.

IMO, you could buy any of those without thinking about it and be very happy with
any of them, and all can be used in non-macro applications also.
08-02-2008, 07:32 AM   #7
Inactive Account




Join Date: Sep 2007
Location: Calgary, AB
Photos: Gallery
Posts: 942
What he's saying is that scientifically speaking, a lens that is sharper at 2.8 than f4 is capable of better resolution and was analyzing the ratios on that basis. By taking the lenses with the highest mean scores and then checking that ratio he's just sorting which one theoretically could be the highest resolver of the bunch.

I do wonder though along the lines of what others are saying, if aperture wouldn't negate a lot of the advantages of a top resolving glass and even out the field?
08-02-2008, 08:33 AM   #8
Senior Member




Join Date: Jan 2008
Location: Barrie, ON
Photos: Gallery
Posts: 174
maybe I'm just being naive, but all of the lenses are in the same area (2100/2400). Is that really that much of a difference? Are you going to be making 10' wide posters? If not, is that extra little bit going to be bothersome? Good luck though and let us know what you decide.

08-02-2008, 01:56 PM   #9
Veteran Member
philmorley's Avatar

Join Date: Mar 2007
Location: in a house in Armidale, Australia
Posts: 472
from memory photodo.com rated one of the contax lenses sharpest but a tokina? macro, pentax 50 macro and pentax 85 were almost there too.
08-02-2008, 05:50 PM   #10
Veteran Member
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,863
Original Poster
Hi, so, I created a lot of confusion. I'll go through the individual messages. In a second post, I'll provide an example of what I mean

QuoteOriginally posted by séamuis Quote
you absolutely should which makes this whole thing rather bunk to be honest because at f11 what lens isn't sharp?
I know the DoF is razor thin. That wasn't my point. At f11, no lens is really sharp because of diffraction (max. resolution is about 7.4 microns which isn't even enough for true 1:1 on the K20D).
QuoteOriginally posted by Nesster Quote
Also, the resolution numbers aren't directly comparable between cameras, so the Canon numbers won't match Pentax, and neither will match Nikon, and so forth. I see you applied some sort of correction factor, maybe that helps.[...]false accuracy
I know about the false accuracy. I used the lens data in boldface to calibrate across mounts. This isn't totally correct but the best I can do. Fortunately, some lenses were tested for multiple mounts and I used this for my calibration.

QuoteOriginally posted by jsherman999 Quote
Viv 105, FA 50 2.8, DA 35ltd, Sigma 70/105/180, Tamron 90, VL 125.
I already own a DA35 Ltd. Great lens and it really gives 1:1.
The point which I didn't get across: I want to go further down, up to 10:1 which is were the lights finite wave length would stop you

QuoteOriginally posted by thePiRaTE!! Quote
What he's saying is that scientifically speaking, a lens that is sharper at 2.8 than f4 is capable of better resolution and was analyzing the ratios on that basis. By taking the lenses with the highest mean scores and then checking that ratio he's just sorting which one theoretically could be the highest resolver of the bunch.
I do wonder though along the lines of what others are saying, if aperture wouldn't negate a lot of the advantages of a top resolving glass and even out the field?
Yes. The lower the aperture of max. resolution the better the lens. This is a universal law and true across mounts.
I don't plan to stop down the lens. This isn't possible anymore if you go beyond 1:1. You have to use the best resolving aperture and use focus stacking in software, i.e. dead subjects.

QuoteOriginally posted by ghost Quote
maybe I'm just being naive, but all of the lenses are in the same area (2100/2400).
photozone.de figures are limited by the sensor resolution. E.g., Pentax K10D is limiting figures to 2592 LW/PH, because this is the sensor's no. of pixels. All the lenses I mentioned are far beyond the sensor's capabilities and therefore, even small differences can mean huge resolution differences for the lens.

Also, I don't mount the lens to the body. I reverse-mount (front to front) it to another lens, e.g., a 50mm to a 300mm. The 300mm will magnify 6x and give the K20D a 0.8 micron sensor, so to speak. What resolves good on a 5 micron sensor (K20D) may resolve badly on a 1 micron sensor. Which is why I need such a perfect lens to go beyond 1:1. And by doing so, I continue to operate both lenses in their designed way, namely at infinite focus.
08-02-2008, 05:56 PM   #11
Inactive Account




Join Date: Sep 2007
Location: Calgary, AB
Photos: Gallery
Posts: 942
You're just going to make yourself paranoid of germs with that lens you know.

hah, j/k - what will you be shooting? sounds interesting.
08-02-2008, 05:56 PM   #12
Veteran Member
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,863
Original Poster
QuoteOriginally posted by philmorley Quote
from memory photodo.com rated one of the contax lenses sharpest but a tokina? macro, pentax 50 macro and pentax 85 were almost there too.
The pentax 50 macro isn't in the top league. Thanks for the other pointers. I'll look them up.
08-02-2008, 06:06 PM   #13
Veteran Member
deejjjaaaa's Avatar

Join Date: May 2007
Location: steel city / rust belt
Posts: 2,046
QuoteOriginally posted by thePiRaTE!! Quote
You're just going to make yourself paranoid of germs with that lens you know.
look at that person first - OP has long road ahead of him to get there

extreme macro 27:1 photo - fotoopa photos at pbase.com

inside Photo Gallery by fotoopa at pbase.com

fotoopa's Photo Galleries at pbase.com
08-02-2008, 06:18 PM   #14
Veteran Member
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,863
Original Poster
Here is an example of what I mean:

A Zeiss 50mm f/1.4, stopped down to f/4 (it's aperrture of max. resolution), reverse-mounted to a Pentax DA* 300mm f/4 (aperture doesn't matter on this side as it is effectively f/(4*6) = f/24 anyway).

I show to magnifications from a 50 Euro banknote / bill.
  1. The bill
  2. A magnification from the blue area with the yellow stars (in the middle of the right third). The blue lines are 400 microns apart. The smallest structures I can identify are about 3 microns large.
  3. A magnification from the hologram part (at the right border), i.e., a piece of one of the four bright rectangular lines in the corners of it. The line width (and image height) is 430 microns.
    The two vertical scratch lines in the right third of it are ~6 microns apart, i.e., about the distance of two sensor pixels in the K20D!
    Each individual scratch line is ~2 pixels wide which is 1.8 microns.

The theoretical limit of a 300 lp/mm lens is 1000microns/600=1.67 microns and I am pretty close already!

So far, I have achieved about 3:1 macro magnification and my question related about how to go even further. At about 1 micron you would start to see bacteria
  • My last image shows pollen-loaden parts of a blooming flower! As you can see, shooting at this magnification is no easy task. (Actually, I thought I would have taken a shot of a living wasp walking on the flower; but I missed it...) (The image covers an area of 2.7 x 4 mm only...)

Last edited by falconeye; 06-15-2011 at 05:28 AM.
08-02-2008, 06:44 PM   #15
Veteran Member
Jewelltrail's Avatar

Join Date: May 2008
Location: Rhode Island
Photos: Albums
Posts: 4,180
A Zeiss 50mm f/1.4, stopped down to f/4 (it's aperrture of max. resolution), reverse-mounted to a Pentax DA* 300mm f/4 (aperture doesn't matter on this side as it is effectively f/(4*6) = f/24 anyway).

QuoteQuote:
I show to magnifications from a 50 Euro banknote / bill.
1: The bill
2: A magnification from the blue area with the yellow stars (in the middle of the right third). The blue lines are 400 microns apart. The smallest structures I can identify are about 3 microns large.
3: A magnification from the hologram part (at the right border), i.e., a piece of one of the four bright rectangular lines in the corners of it. The line width (and image height) is 430 microns.
The two vertical scratch lines in the right third of it are ~6 microns apart, i.e., about the distance of two sensor pixels in the K20D!
Each individual scratch line is ~2 pixels wide which is 1.8 microns.

The theoretical limit of a 300 lp/mm lens is 1000microns/600=1.67 microns and I am pretty close already!


It appears Falconeye is the appropriate title for you--LOL. Seriously, this is fascinating work--thanks for the post!

Regards
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
canon, factor, k-mount, lens, macro, matter, mount, pentax lens, resolution, sigma, slr lens, zeiss
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Sharpest lens in Pentax Mount HoBykoYan Pentax SLR Lens Discussion 27 06-30-2010 01:56 PM
Sharpest Lens you own? Eagle_Friends Pentax SLR Lens Discussion 176 05-14-2010 05:37 AM
Which fast (better than F2) AF lens is sharpest at f1.7. pcarfan Pentax SLR Lens Discussion 4 10-01-2009 02:35 PM
Pentax 67 Sharpest Lens desertscape Pentax Medium Format 6 06-07-2009 05:58 AM
landscapes... which lens is sharpest at F16 to F32 etc? slip Pentax SLR Lens Discussion 7 01-06-2007 07:41 PM



All times are GMT -7. The time now is 09:58 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top