NikonGear'23

Gear Talk => Lens Talk => Topic started by: Michael Erlewine on May 30, 2021, 14:05:42

Title: Focus Throw: Laowa 100mm f/2.8 Ultra-Macro APO Lens for Nikon Z
Post by: Michael Erlewine on May 30, 2021, 14:05:42
I’ve had a little more time to play with the Laowa 100mm f/2.8 Ultra-Macro APO Lens for Nikon Z mount. I show two photos here, one using the Laowa 100mm macro with its short focus throw and the other using the classic Nikkor APO El Nikkor 105mm f/f.6 lenn with reasonable focus throw..

The Laowa does OK, but the problem is, as many pointed out earlier, that the focus throw is too short. This is about the best I could do with the short focus throw, while the APO El Nikkor had much more of a throw.

For most photography, this is not going to be a problem, but for tight focus stacking it certainly is. For me to use the Laowa 100mm APO requires I will have to mount it on a focus rail to get a longer throw. Anyone else have the same problem?

Also, these are DX size photos, not FX. I forgot to change it.

Refer to the file name to distinguish these lenses, please.
Title: Re: Focus Throw: Laowa 100mm f/2.8 Ultra-Macro APO Lens for Nikon Z
Post by: Birna Rørslett on May 30, 2021, 15:00:30
I do have acquired the 100mm F72.8 Laowa for close-up work. In general, images are very good, however I was less than pleased by the short focus throw. As long as I avoid going to 1:1 or beyond, it's doable and the lens is a nice, quite low-cost alternative to the elusive 125/2.5 APO-Lanthar. Putting the lens hood on is a reminder as it will prevent one venturing into that magnification range anyway -- it simply makes it impossible to put the lens at the reduced working distance occurring there.
Title: Re: Focus Throw: Laowa 100mm f/2.8 Ultra-Macro APO Lens for Nikon Z
Post by: richardHaw on May 30, 2021, 15:02:55
the micro-nikkor 50mm 3.5 and micro-takumar 50/4 will be nice alternatives :o :o :o
Title: Re: Focus Throw: Laowa 100mm f/2.8 Ultra-Macro APO Lens for Nikon Z
Post by: Michael Erlewine on May 30, 2021, 20:12:16
I add here a FX photo on an Iris, taken with the APO El Nikkor f/5.6 just to remind those interested in what a very high-quality lens is all about. Not putting the Laowa down, because I use it, and it is a heck of a bargain, yet this is why I have spent money are expensive lenses, as well.
Title: Re: Focus Throw: Laowa 100mm f/2.8 Ultra-Macro APO Lens for Nikon Z
Post by: dickb on May 31, 2021, 21:13:08
The Apo EL Nikkor doesn't have any focus mechanism, so its focus throw is a function of the helicoid or bellows  you use with it. Good to hear you have one that suits you well. I take it the Laowa is a floating elements / internal focussing design? Otherwise an additional helicoid may help the focus throw in the close focus region.
Title: Re: Focus Throw: Laowa 100mm f/2.8 Ultra-Macro APO Lens for Nikon Z
Post by: Michael Erlewine on June 01, 2021, 00:42:22
The Apo EL Nikkor doesn't have any focus mechanism, so its focus throw is a function of the helicoid or bellows  you use with it. Good to hear you have one that suits you well. I take it the Laowa is a floating elements / internal focusing design? Otherwise an additional helicoid may help the focus throw in the close focus region.


Yes, the APO El Nikkor needs a bellows or helicoid, while the Laowa 100mm needs a focus rail for anything fine like stacking. One can do a "short stack," meaning a few shots at key parts of the image and merge those, but any serious number of layers needs a focus rail, OMO.