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01-20-2021, 03:18 PM   #421
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QuoteOriginally posted by bdery Quote
Well, the Laowa has no AF so the point is moot
Not quite moot, since AF may be an advantage for Pentax in some contexts even if it is as slow as molasses in LV.

01-24-2021, 07:24 AM   #422
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Today, I informally tested sharpness of this lens associated to a 13mm extension ring and to a SMC Pentax-F 1.7x AF Adapter, versus a Mitakon 85mm 1-5x Super Macro.
You can click the pictures to see larger version.

Here is the Laowa combo:


My subject is a French stamp (intentionally placed at an angle, in order to avoid front/back-focus problems), here is the stamp in its booklet:




Here is the stamp at 1:1:



Here is the stamp at about 4:1, full picture:



The focus is not exactly on the same place on every photo but it is not relevant as I only want to compare sharpness. Each photo has been taken wide open.

100% extract, Laowa 100mm:



100% extract, Mitakon 85mm:


For information, 100% extract, Oshiro/Bresser 60mm, same combo than the 100mm:


The Laowa looks way better than the two others.
01-24-2021, 07:47 AM   #423
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A quick question: the stamp is supposed to be all in a plane. why the photos you take look like a 3D object? Is it due to imperfect alignment?


QuoteOriginally posted by tryphon4 Quote
Today, I informally tested sharpness of this lens associated to a 13mm extension ring and to a SMC Pentax-F 1.7x AF Adapter, versus a Mitakon 85mm 1-5x Super Macro.
You can click the pictures to see larger version.

Here is the Laowa combo:


My subject is a French stamp (intentionally placed at an angle, in order to avoid front/back-focus problems), here is the stamp in its booklet:




Here is the stamp at 1:1:



Here is the stamp at about 4:1, full picture:



The focus is not exactly on the same place on every photo but it is not relevant as I only want to compare sharpness. Each photo has been taken wide open.

100% extract, Laowa 100mm:



100% extract, Mitakon 85mm:


For information, 100% extract, Oshiro/Bresser 60mm, same combo than the 100mm:


The Laowa looks way better than the two others.
01-24-2021, 09:31 AM   #424
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QuoteOriginally posted by tryphon4 Quote
My subject is a French stamp (intentionally placed at an angle, in order to avoid front/back-focus problems)
Sorry for my bad English, I seem not having being clear: I intentionally did not want the subject and the sensor to be parallel because when they are parallel, you can get front focus or back focus, and when they are not parallel the focus point can change but there is always something in focus.

My aim was not to determine whether the lens is flat field or not, I just don't care about that, my only concern was about maximum sharpness.

01-25-2021, 04:23 PM   #425
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QuoteOriginally posted by tryphon4 Quote
Sorry for my bad English, I seem not having being clear: I intentionally did not want the subject and the sensor to be parallel because when they are parallel, you can get front focus or back focus, and when they are not parallel the focus point can change but there is always something in focus.

My aim was not to determine whether the lens is flat field or not, I just don't care about that, my only concern was about maximum sharpness.
I find that printing screen patterns are too crude to judge resolution at macro ranges. Film grain is perfect!
01-25-2021, 05:29 PM   #426
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Focus stacking is your friend.......



QuoteOriginally posted by JensE Quote
I've written up a 4-way comparison of macro lenses on the KP at 1:1 and a discussion of the useful aperture range for the LAOWA 100mm at 2:1 on the German Pentaxians forum. The later may be of interest in this thread, so here's a brief version in English.

I wanted to know how far I can close down the aperture at 2:1 before diffraction takes away any resolution advantage over a crop from a 1:1 picture. I took a series of pictures at different apertures both at 2:1 and 1:1 of flowers of a willow, that somebody had cut down. Much easier to keep still than a bee , but with similar detail and contrast. The Full scene taken with a KP at 2:1 and f/8

What you can see is that the LAOWA 100mm is sharp at 2:1 wide open already. If any, improvements by stopping down to f/4.0 are minor. Chromatic aberrations are very well corrected, transition into both front and back unsharp regions is pleasant, some contouring is going on in the highlight disks a little further from the focal plane. Already at f/5.6, details are very slightly reduced. At f/8.0 (2:1), everything one gains in terms of detail from the increased magnification over the 1:1 shot at similar DoF, is eaten up by diffraction. There are some advantages in terms of noise/color, but I may have underexposed a bit, exaggerating the effect.

So in conclusion, to really reap the benefit of high magnification, you have to shoot at large to medium apertures. Close down to f/8 at 2:1 and you could as well use f/5.6 at 1:1 and crop instead.
01-25-2021, 06:11 PM   #427
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QuoteOriginally posted by Wheatfield Quote
Focus stacking is your friend.......
Most of my subjects are not exactly behaving, when I ask them to pose for a stack . Still I like to capture some of their behavior at high magnification.
01-26-2021, 02:45 AM - 1 Like   #428
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QuoteOriginally posted by JensE Quote
Most of my subjects are not exactly behaving, when I ask them to pose for a stack . Still I like to capture some of their behavior at high magnification.
A friend of mine used to do macros of bugs by capturing them and putting them in a jar in the fridge for a while. Doing that generally gave him 10 minutes or so to photograph them until they warmed up enough to become uncooperative.

01-26-2021, 02:51 AM   #429
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QuoteOriginally posted by Wheatfield Quote
A friend of mine used to do macros of bugs by capturing them and putting them in a jar in the fridge for a while. Doing that generally gave him 10 minutes or so to photograph them until they warmed up enough to become uncooperative.
Thanks, I'm aware of this option and that many people photograph bugs in early morning hours. I have used it e.g. to document mites on bees, but it's the 'behavior' part that isn't exactly working this way ...
02-04-2021, 07:13 AM - 6 Likes   #430
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Guys, the in-depth review of the Laowa 100mm 2x macro is now online!

Laowa 100mm F2.8 2x Ultra Macro APO Review - Introduction | PentaxForums.com Reviews
02-04-2021, 01:30 PM   #431
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I read the review yesterday, it is very interesting.

By the way, this lens is rated 7.9/10 while the 60mm is rated 8.1/10 but I still prefer the 100mm over the 60mm.
02-04-2021, 02:40 PM   #432
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QuoteOriginally posted by tryphon4 Quote
By the way, this lens is rated 7.9/10 while the 60mm is rated 8.1/10 but I still prefer the 100mm over the 60mm.
In other words, they are close.

IIRC, the ergonomics and aberrations are the two main differences.
02-05-2021, 12:11 PM - 1 Like   #433
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Laowa 100mm

I`m no longer a Pentax user but I also use the 100mm Laowa Macro on my Sony. This is a test shot of a silicon wafern at 1.4x magnification at f2.8. I shot a stack in small 5m steps and took the sharpest in each section, 100% crops of a 60 MP shot of a Sony ARiv.
This is an extraordinary good lens for its price, and at pixelshift it shows that it can resolve more than the 60 Megapixel :-)
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02-18-2021, 04:32 PM - 4 Likes   #434
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I took the first 'real' pictures with the Laowa 100mm today. We had 10C and sun on the hives, so the bees decided to clean and collect some water. This bee's judgement about the temperature over the melting snow wasn't very accurate, I'm afraid. Looks like she held onto that Thyme branch hoping to get warmer ...




Taken at f/8, 2:1 using a K-1. Cropped to about 60% width and 16:10 format. Lit by flash using a diffuse reflective umbrella.


Detail at 100%:
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Last edited by JensE; 02-18-2021 at 04:41 PM.
5 Days Ago   #435
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QuoteOriginally posted by JensE Quote
I took the first 'real' pictures with the Laowa 100mm today. We had 10C and sun on the hives, so the bees decided to clean and collect some water. This bee's judgement about the temperature over the melting snow wasn't very accurate, I'm afraid. Looks like she held onto that Thyme branch hoping to get warmer ...




Taken at f/8, 2:1 using a K-1. Cropped to about 60% width and 16:10 format. Lit by flash using a diffuse reflective umbrella.


Detail at 100%:
looks sharp!
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