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02-25-2018, 03:31 PM - 3 Likes   #1
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LAOWA 25mm F2.8 2.5-5X ULTRA MACRO for K-mount

I’m believe this lens was known about before, but Laowa is going to be showing it at CP+ and confirmed that there will be a K-mount version.

?????MF????LAOWA 25mm F2.8 2.5-5X ULTRA MACRO? - ???? Watch

02-25-2018, 05:16 PM   #2
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I knew about Venus lens but not about this ultra macro one. Does it mean we could reach a 5:1 magnification?
Any indication about AF/MF?
02-25-2018, 05:20 PM   #3
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No infinity focus - so a very specialised lens. Interesting though.
02-25-2018, 05:25 PM   #4
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Very interesting. No infinity focus of course, but full frame.

Here is a linked product announcement with a MTF chart and a photo of the lens in the full extended configuration.

Edit: It looks like the aperture ring is near the front element so most likely there will be no stop-down lever on the K-mount. Full manual stop down metering and manual focus - not unlike using a bellows.

LAOWA 25?? F2.8 2.5-5X ULTRA MACRO ?????????? - SIGHTRON

Google translate link:
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Last edited by Not a Number; 02-25-2018 at 05:42 PM.
02-25-2018, 05:41 PM   #5
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So its basically an enlarger lens, not useful for "regular" photography. But it should be great for closeups of stamps, coins..
I wonder what the working distance is at max magnification
02-25-2018, 05:44 PM - 1 Like   #6
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QuoteOriginally posted by Na Horuk Quote
So its basically an enlarger lens, not useful for "regular" photography. But it should be great for closeups of stamps, coins..
I wonder what the working distance is at max magnification
· It is possible to secure a working distance of 40 mm (5 times) to 45 mm (2.5 times) by optical design with a special configuration. It can correspond to various lighting to obtain better shooting result (via google translate)
02-25-2018, 06:07 PM - 1 Like   #7
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lenses like this look fun, but with no aperture lever there's no benefit to using it over a reversed 28mm lens.

if i put a reversed 28mm on the end of all my extension tubes (about 150mm), it's a little over 7:1. working distance for the dfa 50mm macro runs out a little over 3:1. maybe kaf4 will make it possible for an A setting for these kind of lenses... but afaik none of the (2:1, the mitakon 4:1) apertures communicate with any brand body.
02-26-2018, 04:11 AM   #8
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Interesting enough to make me think about getting my first third-party lens.

02-26-2018, 07:26 AM   #9
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QuoteOriginally posted by sculptor666 Quote
lenses like this look fun, but with no aperture lever there's no benefit to using it over a reversed 28mm lens.
The main benefit is having a variable magnification setup, one where there is no need to change lenses (or tubes) to change the magnification. In this sense, a better comparison would be to a 135mm plus reversed 28-70mm, a combo which would cover roughly 2:1 to 5:1.

But I agree that Laowa's macro products would really benefit from having an aperture linkage, and that without it they bring little advantage (maybe weight/convenience) over a more DIY approach...
02-26-2018, 07:53 AM   #10
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The layout of the lens precludes an aperture lever unless they come up with some hokey telescoping lever which would likely jam.

One of their UWA lenses has the lever and even Ka mount with contacts. I doubt they could put an electromechanical aperture to use the KAF4 mount without substantially increasing the barrel size either.

As noted about the advantages is having variable magnification without having to change tubes, have the rear elements and mechanism of the lens esposed or use a bulky and fragile bellows. A working distance of 40 to 45mm is a big plus as I'm lucky to get 10 -15mm with a reversed 28mm lens on my bellows.

You don't have an aperture linkage with reversed lenses on tubes. You do if you have any of the Pentax Auto Bellows (M42, M, K and A) but you still have to stop it down manually unless you made a dual mechanical and electronic shutter release cable.
02-26-2018, 09:50 AM   #11
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working distance at 5:1 on my reversed 28 (85mm extension) is around 40-45mm, of course working distance decreases as magnification goes up.

for me, it's easier to hold the aperture lever open with my finger than having to click it down to f 16 or whatever from wide open.... but it least laowa put it at the far end of the lens.

someone please make an eos-kaf4 converter so we can all use the mp-e 65 unless pentax makes a 60-70mm kaf4 macro and wr kaf4 helicoid extention tubes yes please.
02-26-2018, 12:25 PM   #12
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My ideal macro lens would have a range of 1:3 to 3:1. Maybe 80mm and F/4 so that it's not too big. No need for infinity focus, but auto-aperture please. Anyone listening?
03-04-2018, 10:29 AM - 1 Like   #13
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A review:

Laowa 25mm f/2.8 2.5x - 5x Ultra Macro lens review

It looks pretty decent... a little annoying I didn't know about it as I might have considered this over the Mitakon 20mm 4-4.5x macro I picked up a couple months ago (ok, it was relatively inexpensive). Ahh well, is it possible to have too many macro lenses? I'm not sure...

The 2.5-5x range would have some utility and only a small gap when paired with a dfa100mm + DCR250 (goes to 2x mag).

I'd also love an aperture lever, but I'm thinking the simplicity of the construction helps these Chinese manufacturers crank these lenses out and include the K-mount option. Annoying, but I can accept it as a practicality.
03-07-2018, 02:09 PM   #14
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Its official, and the price of 399$ isnt too bad.
03-07-2018, 04:30 PM   #15
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QuoteOriginally posted by Simen1 Quote
Its official, and the price of 399$ isnt too bad.
For zero automation and very specific usage I find it a bit pricey...
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