Cosina Voigtlander 110 APO-Lanthar Sharpness Issue

RobertOToole · Post by **RobertOToole** » Fri Dec 20, 2019 10:19 am

Yesterday I received a rental Cosina Voigtlander 110 APO-Lanthar for a test this weekend but after doing a quick check on my A6300, there was an issue!

100% view center crop, jpegs, no sharpening. Lens is clean, no smudges, and no I didn't drop the lens

CV110 vs Sigma Art 70

CV110 vs CV125 SL

I sent the rental company these crops and they are going to send me a replacement sample so I will keep you posted.

This is a good example of why you need to test your new equipment against a reference.

Also this is a good example of the sharpness out of the Sigma 70 Art lens

Surprises are popping up even before I've had a chance to start the test,

Robert

RobertOToole · Post by **RobertOToole** » Fri Dec 20, 2019 10:27 am

Update

Good news.

A CV110 replacement is shipping for Saturday delivery via Fedex.

LensRentals customer service is doing an excellent job so far.

They offered the Sat. delivery, I didn't insist.

Lou Jost · Post by **Lou Jost** » Fri Dec 20, 2019 11:49 am

I second the high quality of the 70mm Art lens. It's very good.

chris_ma · Post by **chris_ma** » Fri Dec 20, 2019 12:49 pm

wow, that certainly looks like something is spooky with that lens.

I like the lensrental blog, they have a lot of MTF tests.
I actually thought I've read there that they run each lens through a quick automated MTF check after each rental, apparently not with this lens.
But good to know that they help to solve the issue.

the Sigma 70mm has also been tested by the digital picture. not on macro setting, but still a nice site for comparison:
https://www.the-digital-picture.com/Rev ... &APIComp=0

RobertOToole · Post by **RobertOToole** » Fri Dec 20, 2019 1:12 pm

chris_ma wrote:wow, that certainly looks like something is spooky with that lens.

I like the lensrental blog, they have a lot of MTF tests.
I actually thought I've read there that they run each lens through a quick automated MTF check after each rental, apparently not with this lens.
But good to know that they help to solve the issue.

the Sigma 70mm has also been tested by the digital picture. not on macro setting, but still a nice site for comparison:
https://www.the-digital-picture.com/Rev ... &APIComp=0

Yes, that is true Chris, I've read the same, they MTF every lens wide open to find problems before they rent. They also test each lens over time and retire the lenses after a certain amount of time elapses.

Not sure if you read the post about the shipment of Sigma lenses that was off. Sigma USA contacted Japan about it and they asked for a sample back and turns out the entire shipment was damaged between Japan and US. So the story was that Sigma japan decided to test and re-engineer the shipping containers they use to stop the problem from happening again.

Maybe that is the same thing that happened here, maybe there was an issue with shipping?

Anyway I will report back. The 125mm SL lens is certainly sharp, the new 110 should be similar or even better on the Sony.

Best,

Robert

RobertOToole · Post by **RobertOToole** » Fri Dec 20, 2019 1:15 pm

Lou Jost wrote:I second the high quality of the 70mm Art lens. It's very good.

Yes, it is, and the price point is very good also.

I am getting the Sony FE 90mm f/2.8 Macro G OSS Lens today which is about 2x the price of the Sigma. It will be interesting to see how they compare at 1x.

Best,

Robert

Lou Jost · Post by **Lou Jost** » Fri Dec 20, 2019 1:48 pm

I'll be interested to know the answer to that. I am a big fan of its optics, though I hate its focus-by-wire system.

Also, for any S1R owners who might be reading this and thinking to buy it: DON'T DO IT. Sigma's claim that this lens in Canon mount would be compatible with the S1/S1R through the Sigma MC21 mount converter is false. The focus bracketing function, the most important feature of this camera for macro photographers, is disabled with this lens.

I also can't get the "Linear" focusing mode to work, though this may be my fault for not setting something somewhere. This mode would make the focus-by-wire mechanism behave more like a manual-focus lens. Instead the focus is "gestural", the lens travel depends on the amount of torque you apply. Very difficult to use for fine macro focusing.

A new native L mount version is due to come out in a month or two. You should wait for that.

Chris S. · Post by **Chris S.** » Sat Dec 21, 2019 1:06 am

Robert, this is very interesting. I'll be watching to see how it plays out.

chris_ma wrote:I like the lensrental blog, they have a lot of MTF tests.
I actually thought I've read there that they run each lens through a quick automated MTF check after each rental, apparently not with this lens.

I also like their blogs, and also recall that they test lenses upon every return. But I have a memory that there are some things that their impressive test equipment can't handle, and something I consider important that is in the "can't handle" category. Was it the macro range of a macro lens?

Not surprised, but pleased to hear, that their customer service is treating the customer well, here.

--Chris S.

chris_ma · Post by **chris_ma** » Sat Dec 21, 2019 4:22 am

Chris S. wrote:I also like their blogs, and also recall that they test lenses upon every return. But I have a memory that there are some things that their impressive test equipment can't handle, and something I consider important that is in the "can't handle" category. Was it the macro range of a macro lens?

yeah, now that you mention it I also seem to remember that their machine is set up for infinity (or near that).
since the findings here are that even 1:10 is closer to infinity then to 1:1 I guess that makes sense for normal use
chris

RobertOToole · Post by **RobertOToole** » Sat Dec 21, 2019 9:10 am

Chris S. wrote:Robert, this is very interesting. I'll be watching to see how it plays out.

chris_ma wrote:I like the lensrental blog, they have a lot of MTF tests.
I actually thought I've read there that they run each lens through a quick automated MTF check after each rental, apparently not with this lens.
I also like their blogs, and also recall that they test lenses upon every return. But I have a memory that there are some things that their impressive test equipment can't handle, and something I consider important that is in the "can't handle" category. Was it the macro range of a macro lens?

Not surprised, but pleased to hear, that their customer service is treating the customer well, here.

--Chris S.

I've spent more time reading that blog than I would like to admit.

The test bench was designed to test loaner lenses wide open at infinity. I don't think the test bench can test at closer distances but they don't really have a purpose to test lenses at closeup distances anyway. The bench isn't designed for that.

BTW the bench rotates each lens to tests each corner automatically, the results are averaged for the MTF data, I haven't seen that done anywhere else.

I have read macro lens comparisons on the blog including MTF data at 1:2. For these close-up tests they generated the MTF data with imatest with a closeup test chart.

Maybe that was it?

Other than Miljenko and Mark Goodman I don't think I've seen any MTF data posted online that was made at closeup distances, I could have left someone out maybe?

Best,

Robert

Macro_Cosmos · Post by **Macro_Cosmos** » Sat Dec 21, 2019 9:10 am

That looks abysmal, it's definitely damaged optically. Glad to hear that Lesnrentals is prompt on the customer service. I'm guessing it was damaged during shipping, perhaps the lens' construction isn't the most robust; but then unless the lens is specifically designed to be robust, it's not their fault if shipments are handled in a rough manner.

Edmund Optics ruggardised lenses: https://www.youtube.com/watch?v=k-Xhbrz4esY

chris_ma · Post by **chris_ma** » Sat Dec 21, 2019 10:33 am

Macro_Cosmos wrote:Edmund Optics ruggardised lenses: https://www.youtube.com/watch?v=k-Xhbrz4esY

interesting video, but I'm a bit surprised they used a camera with rolling shutter for the high speed shots - makes it look like the lenses are made out of rubber

RobertOToole · Post by **RobertOToole** » Tue Dec 24, 2019 9:59 pm

Update on the Cosina Voigtlander 110 performance issue

The good news:

LensRentals customer service did get another CV 110 in my hands on Saturday

The bad:

The replacement was better but still the quality was not as expected, I can only guess something is wrong with that entire CV110 shipment. I plan to post some images when I get a chance so you can see for yourself.

Over the weekend I did have a chance to compare the CV110 with a total of 10 lenses at 1x on a rented Sony A7R IV. 2 more issues came up during the test. The Sony 90 G OSS lens performance was way off with soft corners and bright lateral blue and pink CAs in the corners. The Canon 100 IS sharpness was okay but also had a problem with CAs, but this time they were ultra bright red fringing in the center of the frame, there is no way type of thing is normal, is it? The CV 125 had the usual dark blue fringing but this issue might not be the lens.

There were some big surprises during the test, the performance of the Sigma 70 Art was absolutely fantastic, and the Canon MP-E 65 is very good at 1x, one of the better lenses in the test, who knew?

Best and happy holidays,

Robert

JLyle · Post by **JLyle** » Wed Dec 25, 2019 10:40 am

I purchased and returned 2 different 110mm CV lenses and in between I rented one from Lensrentals. All 3 copies had various skew issues, softness, CA and even in the center, wide open and a stop down image quality was just not there. The 65mm CV lens is a different story. Hard for me to understand how CV got the 110mm so wrong and the 65mm so right. Oh, well.

Lyle

Lou Jost · Post by **Lou Jost** » Wed Dec 25, 2019 1:15 pm

That's really unfortunate; I had high hopes for that lens, and would have bought it if I had the money.