Another TTArtisan lens with AF problems...
It looks like AF is to new for them not yet there strength...
AF has never been TTA's strong suit, their manual focus glass is what has turned heads in the last year or two. In fact, the 75/2 was essentially their first lens that got it mostly right and was very reliable and consistent. That's why the regression in the following lenses has been a bit of a surprise. It's possible they used better STM AF motors in the 75 than the small lenses are getting.
Then you have threads like this, where users are having to physically hit their 75/2 to get the focusing motors/rear element to work. In general, you get what you pay for still applies.
On the bright side, I actually like how the TTA 40/2 renders, even with the strong vignetting . The AF is quite competent at f/2, which is how I mostly use the lens, so for me it's still a great choice if size is a priority. (Especially on the Kolari Sony which completely fixes the extreme outwards field curvature)
I still hope they'll release a firmware update to improve AF, especially when the lens is stopped down, but I’m not in any rush as this lens is a keeper for me because it produces very nice images.
Fred Miranda wrote:
On the bright side, I actually like how the TTA 40/2 renders, even with the strong vignetting (Especially on the Kolari Sony which completely fixes the extreme outwards field curvature). The AF is quite competent at f/2, which is how I mostly use the lens, so for me it's still a great choice if size is a priority.
I still hope they'll release a firmware update to improve AF, especially when the lens is stopped down, but I’m not in any rush as this lens is a keeper for me because it produces very nice images.
RoamingScott wrote:
I still much prefer the rendering to the Z 40/2 when it works, so I'm hoping they can sort out whatever is happening with the AF.
agreed, i like the rendering better than the sony 40/2.5 as well. i also only use AF wide open anyway so i haven't been bothered with those issues (it is still less accurate sony's faster lenses at f/2 though). given the price, i'd still call it a good deal.
I would say it's a fantastic 40mm lens with a unique character, regardless of its lower price. It accomplishes everything I want. It is the most compact 40mm with AF among the options, is well built, and feels great in hand. It looks nice as well. AF operates almost silently and accurately at f/2, which is how I use it most of the time, and the rendering is exactly what I like, better than the alternatives including the Sony. I really do not like the strong onion pattern on the 40/2.5. The cherry on the top is that it's actually at 37mm lens.
How could it be even better?
1) For the E-mount version, reverse the focusing ring direction.
2) Correct the AF issue when stopping down the lens.
TTArtisan never responded to my feedback or inquiry, so if more E-mount shooters can, that's the feedback I believe could make this lens even better. (imo)
So Nikon just got a feature that allows full time open aperture focusing no matter what the aperture is "set" to.
I'm curious if using this in conjunction with the "A" setting on the lens would improve things, though that would completely defeat the point of the aperture ring. I'm not wasting any more time testing my current copy, so this theory will have to wait.
Fred Miranda wrote:
[...]
How could it be even better?
1) For the E-mount version, reverse the focusing ring direction.
2) Correct the AF issue when stopping down the lens.
TTArtisan never responded to my feedback or inquiry, so if more E-mount shooters can, that's the feedback I believe could make this lens even better. (imo)
As mentioned (page 7 post #13) I got another firmware from TTA.
I opened it and it turned out to be a firmvare dated 20250811 so somewhat older than version 02 we all have. OK, I loaded it and the lens now still says version 02. That may be confusing. Keep an eye on the fw dates (file name in date format yyymmdd)
With the August 11 fw it's possible to focus (Sony A1, AF-C) from f/2-f/5.6. In very dark situations (tested light situations at EV0 and EV1) it doesn't work all the time at f/5.6. But when do we use that aperture in the dark? F8 can still be problematic. When moving the focus point away from the center my camera/lens-combo sometimes looses track of the focus point. The newer fw (20250814) is a bit better. Perhaps that's where they got lost at TTA?
Anyway, when comparing the TTA 40/2.0 with the FE 40/2.5 in the same situations the Sony lens is all the time a notch better with regards to AF. The Sony is faster, totally silent, doesn't hesitate and is more sticky to the chosen focus point.
That doesn't make the TTA lens bad.
The 20250811 fw is not perfect but it's matching myway of using a 40mm lens better than the 20250814 fw version.
Other findings:
(An error about the speed was mentioned here, my mistake, false info deleted. Sorry for that!)
There is an electro-mechanical problem with the aperture. I noticed that when going back and forth between f/8 and f/9 the aperture blades doesn't move. This was after having passed the f/8 marking once and then going back again towards f/16. Strange. After discovering that (by chance) I checked the aperture stops down to f/2 and found the same problem between f/4 and f/4.5.
The speed difference is of no importance to me. I'm much more interested in the aperture opening than in the transmission numbers.
The aperture blades not reacting to turning the aperture ring is worse. I'll leave some feedback to TTA about the firmware and will of course ask for a replacement lens. Hopefully the problem is a random glitch rather than a systematic error leaving us all with non-functional aperture mechanisms in the future.
Jonas B wrote:
As mentioned (page 7 post #13) I got another firmware from TTA.
I opened it and it turned out to be a firmvare dated 20250811 so somewhat older than version 02 we all have. OK, I loaded it and the lens now still says version 02. That may be confusing. Keep an eye on the fw dates (file name in date format yyymmdd)
With the August 11 fw it's possible to focus (Sony A1, AF-C) from f/2-f/5.6. In very dark situations (tested light situations at EV0 and EV1) it doesn't work all the time at f/5.6. But when do we use that aperture in the dark? F8 can still be problematic. When moving the focus point away from the center my camera/lens-combo sometimes looses track of the focus point. The newer fw (20250814) is a bit better. Perhaps that's where they got lost at TTA?
Anyway, when comparing the TTA 40/2.0 with the FE 40/2.5 in the same situations the Sony lens is all the time a notch better with regards to AF. The Sony is faster, totally silent, doesn't hesitate and is more sticky to the chosen focus point.
That doesn't make the TTA lens bad.
The 20250811 fw is not perfect but it's matching myway of using a 40mm lens better than the 20250814 fw version.
Other findings:
The TTA lens is not that much faster than the Sony 40/2.5. Maybe a third of a stop rather than the expected two thirds of a stop.
There is an electro-mechanical problem with the aperture. I noticed that when going back and forth between f/8 and f/9 the aperture blades doesn't move. This was after having passed the f/8 marking once and then going back again towards f/16. Strange. After discovering that (by chance) I checked the aperture stops down to f/2 and found the same problem between f/4 and f/4.5.
The speed difference is of no importance to me. I'm much more interested in the aperture opening than in the transmission numbers.
The aperture blades not reacting to turning the aperture ring is worse. I'll leave some feedback to TTA about the firmware and will of course ask for a replacement lens. Hopefully the problem is a random glitch rather than a systematic error leaving us all with non-functional aperture mechanisms in the future.
Jonas B wrote:
As mentioned (page 7 post #13) I got another firmware from TTA.
I opened it and it turned out to be a firmvare dated 20250811 so somewhat older than version 02 we all have. OK, I loaded it and the lens now still says version 02. That may be confusing. Keep an eye on the fw dates (file name in date format yyymmdd)
With the August 11 fw it's possible to focus (Sony A1, AF-C) from f/2-f/5.6. In very dark situations (tested light situations at EV0 and EV1) it doesn't work all the time at f/5.6. But when do we use that aperture in the dark? F8 can still be problematic. When moving the focus point away from the center my camera/lens-combo sometimes looses track of the focus point. The newer fw (20250814) is a bit better. Perhaps that's where they got lost at TTA?
Anyway, when comparing the TTA 40/2.0 with the FE 40/2.5 in the same situations the Sony lens is all the time a notch better with regards to AF. The Sony is faster, totally silent, doesn't hesitate and is more sticky to the chosen focus point.
That doesn't make the TTA lens bad.
The 20250811 fw is not perfect but it's matching myway of using a 40mm lens better than the 20250814 fw version.
Other findings:
The TTA lens is not that much faster than the Sony 40/2.5. Maybe a third of a stop rather than the expected two thirds of a stop.
There is an electro-mechanical problem with the aperture. I noticed that when going back and forth between f/8 and f/9 the aperture blades doesn't move. This was after having passed the f/8 marking once and then going back again towards f/16. Strange. After discovering that (by chance) I checked the aperture stops down to f/2 and found the same problem between f/4 and f/4.5.
The speed difference is of no importance to me. I'm much more interested in the aperture opening than in the transmission numbers.
The aperture blades not reacting to turning the aperture ring is worse. I'll leave some feedback to TTA about the firmware and will of course ask for a replacement lens. Hopefully the problem is a random glitch rather than a systematic error leaving us all with non-functional aperture mechanisms in the future.
The TTA 40/2 is indeed about two-thirds of a stop faster according to my calculations. What I notice is that when you compare them side by side, focusing on the same subject at the same distance, the blur appears quite similar because of its wider field of view. Also, if you check the entrance pupil on these lenses, the TTA is noticeably larger.
Thanks for the information on the 20250811 firmware. Would you be able to share it with us? I would love to try it and see if it keeps the same performance at f/2 while improving reliability when stopped down a little.
RoamingScott wrote:
You should throw the Aug 11 firmware on dropbox and share here for further testing
EDIT: 260204: The official fw 03 is out. It seems to work as well as the beta I shared here.
Fred Miranda wrote:
The TTA 40/2 is indeed about two-thirds of a stop faster according to my calculations. What I notice is that when you compare them side by side, focusing on the same subject at the same distance, the blur appears quite similar because of its wider field of view. Also, if you check the entrance pupil on these lenses, the TTA is noticeably larger.
OK. I double checked now and I made mistake using the wrong metered area. I corrected my post above. Thank you!
Thanks for the information on the 20250811 firmware. Would you be able to share it with us? I would love to try it and see if it keeps the same performance at f/2 while improving reliability when stopped down a little.
EDIT 260204: Well, it did work well. But, there is now an official firmware (FE-mount) version 03 available so I have taken the August 11 beta down from my dropbox.
