RustyBug wrote:
Wake me up when you find it ... just to make sure I wasn't dreaming.
Just drop it a few times to randomize element spacing. That should take the edge off sharpness. In this vein, my 50 Lux ASPH eventually loosens up to the point where there is play in the lens body that affects it optically. When this happens, it's quite soft/glowy wide open, but sharpness right back up stopped down a stop or so...
Or Fred could have Yukosteel open it up and check for any adjustable elements for spacing, tilt, etc.. or shims.
Last resort, maybe one of those cinema black mist filters (though not the same thing as SA).
szwayko wrote:
When I see VM skopar 90/2.8 at 2.8, 4 on https://www.fredmiranda.com/forum/topic/1733542/
I think that skopar has better correction for vignetting and maybe it is better for landscapes
szwayko wrote:
When I see VM skopar 90/2.8 at 2.8, 4 on https://www.fredmiranda.com/forum/topic/1733542/
I think that skopar has better correction for vignetting and maybe it is better for landscapes
As this lens (i.e., the Voigtlander 90 f/2 APO) is a stop faster I doubt it is has worse vignetting correction than the APO-Skopar at the same apertures, and for landscapes which are often shot stopped down a couple stops further vignetting is rarely a big issue anyway. The advantage of the APO-Skopar is that it is very small, which some might value. I know I did when I owned the lens.
Steve Spencer wrote:
As this lens (i.e., the Voigtlander 90 f/2 APO) is a stop faster I doubt it is has worse vignetting correction than the APO-Skopar at the same apertures, and for landscapes which are often shot stopped down a couple stops further vignetting is rarely a big issue anyway. The advantage of the APO-Skopar is that it is very small, which some might value. I know I did when I owned the lens.
That’s correct. At f/2.8 and smaller apertures, vignetting is nearly identical between the two lenses. For stopped-down landscapes, I would still prefer the Voigtlander 90mm f/2 APO-Ultron. Both lenses are equally compact, but the Ultron offers superior optical performance.
RustyBug wrote:
Wake me up when you find it ... just to make sure I wasn't dreaming.
There aren't many APO lenses with some residual uncorrected SA but it is not as though they don't exist. One clear example is the Zeiss Otis 28 f/1.4. I had this lens and it is huge, but had wonderful rendering. Wide open at f/1.4 it has, IMO, a nice amount of uncorrected SA, but stopped down just 2 stops the lens is amazingly sharp across the field at f/2.8. You can see that in the MTF charts here:
At f/1.4 the field is pretty flat with rather lower astigmatism, but the contrast levels are about 92%, 78%, and 52% contrast at 10, 20, & 40 lp/mm respectively. This level of performance is not unsharp, but it is not as though they corrected for all the spherical aberrations either. Those MTF charts match my experience with the lens as well.
You see a similar situation with the Zeiss ZE/ZF/Milvus 135 f/2 APO. Note this lens has zero aspherical elements, and this lens too has, IMO, after using it a fair bit some uncorrected spherical aberrations wide open as well. You can see that in the MTF charts here:
Wide open the lens has a very flat field with almost no astigmatism, but the contrast levels are about 92%, 82%, and 61% contrast at 10, 20, & 40 lp/mm. Again the level of performance is not unsharp and just a little sharper than the Otis 28 at f/1.4, but it is not as though the results are totally corrected for spherical aberrations either. The performance, just like the Otus is much higher a couple of stops down, and is notably below several other fast 135mm lenses.
I really like these two Zeiss lenses for their performance, but they are both very large. I would love to see smaller APO lenses that perform more like these two than APO lenses that go for the highest possible sharpness such as the Leica SL APO summicrons. I like it when a lens is a bit less sharp wide open than what it is a couple of stops down.
RustyBug wrote:
Wake me up when you find it ... just to make sure I wasn't dreaming.
While not telephoto lenses and not on par with modern APO designs, the MS Optics lenses offer great correction for longitudinal CA, particularly the 28mm and 35mm Apoqualia versions. They do show noticeable spherical aberration (glow).
Fred Miranda wrote:
While not telephoto lenses and not on par with modern APO designs, the MS Optics lenses offer great correction for longitudinal CA, particularly the 28mm and 35mm Apoqualia versions. They do show noticeable spherical aberration (glow).
It’s a great character lens. I read years ago it was called Apo-qualia because of the LoCal correction. Nice SA on that lens.
I'm going to be in Japan on the 14th of Feb, what do you think are the chances they aren't sold out by then? Is it possible to preorder and pick it up after a couple of weeks?
Stargenx wrote:
I'm going to be in Japan on the 14th of Feb, what do you think are the chances they aren't sold out by then? Is it possible to preorder and pick it up after a couple of weeks?
If you are visiting Tokyo, maybe you could email Map Camera and ask them to hold one for you if you pre-pay you leave a deposit? According to Juha's post above, it’s set to release in Japan on January 23rd. Perhaps same day for the US.
Fred Miranda wrote:
If you are visiting Tokyo, maybe you could email Map Camera and ask them to hold one for you if you pre-pay you leave a deposit? According to Juha's post above, it’s set to release in Japan on January 23rd. Perhaps same day for the US.
Looks like Map is accepting 'reservations' so you might be able to do as Fred recommended. I really liked shopping at Map, floors are divided by brand, with the Leica boutique front and center on the bottom floor. I spent most of my time on the Sony floor, but visited all of them.
Be warned: they have a lot of used lenses in immaculate condition for a good price. I did not leave with only one lens...
This is a great idea, thanks! No idea why I didn't think about this, I think it's a sign of the increasingly impersonal world we live in. I'll report back if they assent in case anyone else is in a similar situation.
The Voigtlander 90mm f/2 APO-Ultron has a minimum focus distance (MFD) of 0.9m, which is longer than the rangefinder coupling limit of 0.7m. This is typical for telephoto lenses designed for the M mount. For instance, the Leica APO-Summicron 90mm f/2 ASPH. has an even longer MFD of 1m..
Neither the Voigtlander nor the Leica APO-Summicron includes a floating element mechanism, which can affect spherical aberration control. While some residual spherical aberration is noticeable wide open on both lenses, the Voigtlander matches the Leica’s performance, apart from the Leica’s lower magnification.
I tested for focus shift by capturing images at f/2, f/2.8, and f/4 without refocusing, followed by refocusing at f/4 for comparison. Focus shift is negligible, and resolution and contrast improve progressively from f/2 to f/2.8 and further at f/4. (Read on to find out that it’s the Leica lens that shows focus shift.)
Overall, the Voigtlander 90mm f/2 APO-Ultron performs excellently at close distances, producing sharp and detailed results. It is already impressively sharp at f/2 but improves further at f/2.8 and slightly more at f/4. The following sequence shows its performance across these apertures.
At 0.9m MFD using LiveView
***Expand the browser window to view the full image without any resizing.
Left: f/2 | Right: f/2.8
Left: f/2.8 | Right: f/4
Left: f/4 | Right: f/4 (refocused) - no discernible focus shift at MFD
For comparison, I’ve included pixel-level crops below, showing the Voigtlander 90mm f/2 APO-Ultron and the Leica APO-Summicron 90mm f/2 ASPH. at their respective MFDs wide open (0.9m vs. 1m).
The results appear similar in terms of resolution and contrast, but the Voigtlander has the advantage of a closer minimum focus distance, allowing for higher magnification and greater detail capture at close range.
Having already compared the Voigtlander to the Leica at infinity and 2m distances, here’s a look at how the Leica performs at its MFD across f/2, f/2.8, and f/4 for further comparison:
Left: f/2 | Right: f/2.8
Left: f/2.8 | Right: f/4
Left: f/4 | Right: f/4: Resolution improves when refocusing at f/4, indicating that the Leica exhibits focus shift.
Jan 09, 2025 at 04:59 PM
Steve Spencer Online • • • • • • • Upload & Sell: On
The Voigtlander 90mm f/2 APO-Ultron has a minimum focus distance (MFD) of 0.9m, which is longer than the rangefinder coupling limit of 0.7m. This is typical for telephoto lenses designed for the M mount. For instance, the Leica APO-Summicron 90mm f/2 ASPH. has an even longer MFD of 1m..
I tested for focus shift by capturing images at f/2, f/2.8, and f/4 without refocusing, followed by refocusing at f/4 for comparison. Focus shift is negligible, and resolution and contrast improve progressively from f/2 to f/2.8 and further at f/4. (Read on to find out that it’s the Leica lens that shows focus shift.)
Overall, the Voigtlander 90mm f/2 APO-Ultron performs excellently at close distances, producing sharp and detailed results. It is already impressively sharp at f/2 but improves further at f/2.8 and slightly more at f/4. The following sequence shows its performance across these apertures.
At 0.9m MFD using LiveView
***Expand the browser window to view the full image without any resizing....Show more →
Fred, I think the Leica 90 f/2 AA doesn't have a floating element design either. There is no mention of a floating element in any of the Leica literature. And in the review at Pebble Place, a site I almost always find trustworthy, the say explicitly, "Unlike the Leica 75mm F2 Summicron-M APO, the 90mm APO does not have a floating lens element (FLE)."
That said as you show here the MFD performance is excellent. It is great that the Voigtlander 90 f/2 APO essentially matches it with a slightly shorter MFD.
Steve Spencer wrote:
Fred, I think the Leica 90 f/2 AA doesn't have a floating element design either. There is no mention of a floating element in any of the Leica literature. And in the review at Pebble Place, a site I almost always find trustworthy, the say explicitly, "Unlike the Leica 75mm F2 Summicron-M APO, the 90mm APO does not have a floating lens element (FLE)."
That said as you show here the MFD performance is excellent. It is great that the Voigtlander 90 f/2 APO essentially matches it with a slightly shorter MFD.
Thanks for the correction, Steve. I always assumed it had a floating element after getting it back from a CLA with Youxin, who mentioned that the focusing is never super smooth because of the FLE. Honestly, I took his word for it and never really checked or tested the lens at its MFD until now. I'll update the text to reflect this.
I’m considering sending my copy to DAG, as I’m still not satisfied with the focusing rotation. It’s not very smooth, even after the CLA. In contrast, the Voigtlander's focusing rotation is buttery smooth.
In this vein, my 50 Lux ASPH eventually loosens up to the point where there is play in the lens body that affects it optically. When this happens, it's quite soft/glowy wide open, but sharpness right back up stopped down a stop or so...
