New Laowa 100mm f2.8 Apo 2x Macro

[ray_parkhurst]

Another 2x offering from Laowa. I love the 60mm, and may buy one of these if it lives up to its hype:

https://www.dpreview.com/articles/61453 ... n?slide=18

[enricosavazzi]

The 24.7 cm focus distance (I assume this is the sensor-to-subject distance, not the working distance) mentioned in the article implies that the FL of this lens massively reduces at high magnification.

This is both good news (the lens design is not just a fixed-focal-length group moving all in one piece, and probably not just a moving front group and a fixed rear group, indicating that considerable effort has been made by the designers) and bad news (working distance at high magnification is far less than computed from a 100 mm FL).

The wide front of the barrel (some 60-70 mm judging from the picture) is a far cry from the reverse-conical barrel of some legacy bellows lenses like the Minolta 100 mm f/4, which have a minuscule front filter thread. Like the wide front of the Laowa 60 mm 2x, the even wider front and filter thread of the Laowa 100 mm are likely dictated by the very recessed position of the front element at infinity focus.

The Laowa 100 mm remains however an interesting lens, especially if geometric distortion is better controlled than in the 60 mm model.

[ray_parkhurst]

I suppose its appeal will also be affected by the final pricing. They put "Apo" in the name so I expect it to be a lot more expensive than the 60mm.

[enricosavazzi]

I suppose its appeal will also be affected by the final pricing. They put "Apo" in the name so I expect it to be a lot more expensive than the 60mm.

"Apo" in a lens name does not need to mean much. Sigma markets most of its lenses as Apo, but very few, if any, are actually apochromatic in a strict sense.

There are also different ways to rate a lens as Apo. Mitutoyo M Plan Apos, for example, are apochromatically corrected with respect to both transversal and axial chromatic aberration. The Rodenstock Apo Rodagon D series is only apochromatic with respect to transversal CA, not axial CA (it is only achromatic in axial CA correction). This is justified by the fact that these Apo Rodagons were originally designed as copy lenses to transfer an image from a flat film to another flat film, so no part of the subject was supposed to be out of focus and therefore axial chromatic aberration was irrelevant. It was no longer irrelevant when Rodenstock began to market these lenses for macro imaging of 3D subjects, but Marketing apparently found it easier to just gloss over the problem rather than redesign the optics (Rodenstock has a track record of producing a mix of excellent lenses as well as significantly poorer legacy optical designs that have not been updated for several decades - only the design of the barrels is updated now and then).

There are also different definitions of the term apochromatic. For example, some apochromatic lenses have all three CA correction wavelengths within the VIS range, while others have one of these wavelengths in the NIR, NUV or UV (Mitutoyo NIR, NUV and UV M Plan Apo series for example). So these expensive multispectral apochromats actually behave only as ordinary achromats in the VIS range.

[ray_parkhurst]

All good info, but my point was that I expect the Apo (true or not) to indicate this lens will be expensive.

[enricosavazzi]

All good info, but my point was that I expect the Apo (true or not) to indicate this lens will be expensive.

It is possible, especially if the lens is a true apo. It is not true of the price of Sigma "Apo" lenses, however, and a few others. Laowa might decide to test the waters and see if the market has an appetite for an unusually expensive macro lens, but this would be a move in a new direction for them.

[Macro_Cosmos]

The lens has apochromatic performance, offering better contrast, colours, and better suppression of chromatic aberrations than the Laowa 105mm STF, which is already impressive when it comes to supression of CA. That lens does have some other issues though, which according to Laowa, will not be present for the 100mm macro lens.

I believe the focus throw is 270 degrees -- not the best. I want 540 degrees. However it is far better than the 60mm and 15mm macro lenses.

At x2, the equivalent aperture is about f4.5-f5, not 5.6.

I've seen many sample photos and it is pretty impressive. I'm sure some forum members are familiar with the overpriced Macro Varon from Schneider. That lens is optimised for 0.5x-3x, with a floating element to compensate for CA. I wonder how well the Laowa can hold up against it.

Also there's another major upgrade from older Laowa lenses which isn't talked about. Laowa figured out the electronic coupling between the lens and the camera, which means Canon and Nikon DSLRs will be able to control the aperture electronically. It no longer acts as an Ai-s lens on Nikons. Even worse when it comes to Canon since there's no way to mechanically couple the lens with the camera. All sorted, I'm glad they figured it out!

(I am not sponsored by them)

[Macro_Cosmos]

"Apo" in a lens name does not need to mean much. Sigma markets most of its lenses as Apo, but very few, if any, are actually apochromatic in a strict sense.

Yes indeed. None of Sigma's "fakePo" lenses are apochromatic, it's a convoluted marketing trickery term to woo customers.

There are also different ways to rate a lens as Apo. Mitutoyo M Plan Apos, for example, are apochromatically corrected with respect to both transversal and axial chromatic aberration. The Rodenstock Apo Rodagon D series is only apochromatic with respect to transversal CA, not axial CA (it is only achromatic in axial CA correction). This is justified by the fact that these Apo Rodagons were originally designed as copy lenses to transfer an image from a flat film to another flat film, so no part of the subject was supposed to be out of focus and therefore axial chromatic aberration was irrelevant. It was no longer irrelevant when Rodenstock began to market these lenses for macro imaging of 3D subjects, but Marketing apparently found it easier to just gloss over the problem rather than redesign the optics (Rodenstock has a track record of producing a mix of excellent lenses as well as significantly poorer legacy optical designs that have not been updated for several decades - only the design of the barrels is updated now and then).

Thanks for the information!

There are also different definitions of the term apochromatic. For example, some apochromatic lenses have all three CA correction wavelengths within the VIS range, while others have one of these wavelengths in the NIR, NUV or UV (Mitutoyo NIR, NUV and UV M Plan Apo series for example). So these expensive multispectral apochromats actually behave only as ordinary achromats in the VIS range.

Yeah, another set of lenses that come to mind are the ultra-micro-nikkors, which most are apochromatically corrected, but only a few is designed to work in the visible range. Still the prices are jacked up by collectors.

Another thing is aprochromatic "element", this is simply deceptive marketing fluff. A single element that is apochromatically corrected is called a superapochromat, extremely expensive. There's also doublet and triplet arrangements with apochromatic performance. All in all, apochromatic is an adjective. "Apochromatic lens" doesn't exist in the strict sense.

There's also various ways to test apochromatic performance... simply having great CA suppression doesn't certify the lens for apochromatic.

[ray_parkhurst]

...
I'm sure some forum members are familiar with the overpriced Macro Varon from Schneider. That lens is optimised for 0.5x-3x, with a floating element to compensate for CA. I wonder how well the Laowa can hold up against it.

I consider the 85MV to be very reasonably priced given its performance, and ability to replace several lenses, making it a one-man band. It is nearly as good at 1x as the 105PN, and at 0.5x and 2x as the 95PN. I do still do keep those around, though.

Also there's another major upgrade from older Laowa lenses which isn't talked about. Laowa figured out the electronic coupling between the lens and the camera, which means Canon and Nikon DSLRs will be able to control the aperture electronically. It no longer acts as an Ai-s lens on Nikons. Even worse when it comes to Canon since there's no way to mechanically couple the lens with the camera. All sorted, I'm glad they figured it out!

For sure this was not clear in any of the materials I read, but makes the lens quite a bit more interesting!

[ray_parkhurst]

...
Yeah, another set of lenses that come to mind are the ultra-micro-nikkors, which most are apochromatically corrected, but only a few is designed to work in the visible range. Still the prices are jacked up by collectors.

The UMNs are all designed for a single wavelength. Which wavelength depends on when the lens was made, and what process node it was intended for. The design parameters were broad coverage and zero distortion at single wavelength, so performance at other wavelengths is compromised.

[JohnyM]

About "APO" optics, i can imagine all sigma "APO" lenses are INDEED apo lenses. And some achro lenses not marked as "APO" are still providing superior color correction in some / most conditions.

"APO" term is very vague, here is excellent read with some examples:
https://www.telescope-optics.net/semiap ... amples.htm
If it's too heavy, just scroll to bottom and read summary

As you can see, CA amount vary greatly depending on design. Even in microscopy, APO means nothing specific nowdays (besides lens being most likely to be excellent).

Fun fact on Nikon example:
Nikon stopped making APO lenses in CFN era!



Why? CFN PlanApo's were corrected for 4 lines, making them technically SUPERACHROMATS:


Next generation CFI VC objectives include additional h line:

Im not aware of proper term for this correction, but Thorlabs and Olympus are calling them SUPERAPOCHROMATS.

PlanFluor objectives could be, and technically SHOULB BE considered as APO. So if sigma was selling Nikon PlanFluors, they would probably be marked as apo.


Edit:
Wiki have simple, yet explanatory graphs. Y axis being crossed x times = lens designation. But achromat lens "curve" can be much flatter than some apochromats.

https://en.wikipedia.org/wiki/Superachr ... ssvg_1.png[/img]

[ChrisR]

Macro Varon from Schneider. That lens is optimised for 0.5x-3x

It's 2x.

[RobertOToole]

JohnyM

Very good thanks for sharing the info.

Fun fact on Nikon example:
Nikon stopped making APO lenses in CFN era!

Why? CFN PlanApo's were corrected for 4 lines, making them technically SUPERACHROMATS

One thing I need to bring up before people get excited about this is that APO or super APO area is very small, at least on the 4x CFN Plan APO. Away from the center the CAs glow like a neon sign!

BTW I have a special 4x comparison I plan on posting later with a few APO lenses.

Im not aware of proper term for this correction, but Thorlabs and Olympus are calling them SUPERAPOCHROMATS.

I believe these also suffer from a small field, 22mm or so if I remember correctly.

PlanFluor objectives could be, and technically SHOULB BE considered as APO. So if sigma was selling Nikon PlanFluors, they would probably be marked as apo.

People like to make fun of Sigma but at least they are a good value and some of the lenses they make are really APO lenses like the 150 OS. What bothers me more are brands that charge a premium for lenses like the Schneider APO-Componons, where a few are definitely not.

Anyway interesting info, thanks again.

[Macro_Cosmos]

Macro Varon from Schneider. That lens is optimised for 0.5x-3x

It's 2x.

Yep, just checked, thanks for the correction.