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Techart PRO AF adapter now In Stock!
  
 
bluloo
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p.27 #1 · p.27 #1 · Techart PRO AF adapter now In Stock!


I have the same set of tubes. I wonder how that setup would work with a Rokinon 85 F1.4, vs the Rokinon and a Marumi DHG +5 macro lens.


Aug 31, 2016 at 05:18 PM
arduluth
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p.27 #2 · p.27 #2 · Techart PRO AF adapter now In Stock!




GMPhotography wrote:
Remember focus is best achieved on vertical lines and not horizontal. Always look for a vertical contrast spot to get the best focus. This really is how Sonys work best


FWIW it's not just Sony cameras - I've seen this behavior in most CDAF cameras I've used. I had the EOS M for a short time, it always had a really hard time focusing when there wasn't something vertical. I remember having to rotate it 30 degrees to get it to lock.



Sep 01, 2016 at 12:12 AM
jankap
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p.27 #3 · p.27 #3 · Techart PRO AF adapter now In Stock!


But what is the reason for this? In the vertical direction there are sensor points too, I suppose.
Is the reason, that the vertical dimension of the sensor is less (24mm)?
Jan

Perhaps the programmer of the camera software thinks in one direction only?



Sep 01, 2016 at 06:50 AM
genji
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p.27 #4 · p.27 #4 · Techart PRO AF adapter now In Stock!


For anyone wondering how long they might have to wait for a Techart PRO ordered from the manufacturer, I received an email this evening with the subject line:

Your TECHART PRO order from August 21, 2016 is SHIPPED

There's only a two hour difference between Hong Kong and Sydney, so the adapter was shipped 11 days after I ordered it.



Sep 01, 2016 at 10:47 AM
DavidBM
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p.27 #5 · p.27 #5 · Techart PRO AF adapter now In Stock!


Yep, I too (also a sydney address) got a shipping notification from TechArt! About a week in my case. Very exciting! The tiny CV 2.5/75 (poor mans summarit) will be fun for portraits...


Sep 01, 2016 at 11:08 AM
darrellc
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p.27 #6 · p.27 #6 · Techart PRO AF adapter now In Stock!



Sure an engineer here can explain, perhaps it is because we don't have global shutter and powerful enough processors? I imagine current sensor readout is done row by row so horizontal contrast changes are faster to calculate than vertical? A guess, of course I've no idea why...
jankap wrote:
But what is the reason for this? In the vertical direction there are sensor points too, I suppose.
Is the reason, that the vertical dimension of the sensor is less (24mm)?
Jan

Perhaps the programmer of the camera software thinks in one direction only?




Sep 01, 2016 at 11:11 AM
BrandonSi
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p.27 #7 · p.27 #7 · Techart PRO AF adapter now In Stock!


Pretty excited to use this guy.. Luckily caught in stock on Adorama 2 days ago.. should be here tomorrow. :P Got a CY/M and M42/M adapter coming from Amazon as well.

Anyone tested M42 lenses at all? I imagine they'll work just fine, assuming the M42/M adapter and the flange (or lack thereof) get along with the few lenses I have. I'm strangely excited to see the Helios 44M autofocus..



Sep 01, 2016 at 11:45 AM
inglis
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p.27 #8 · p.27 #8 · Techart PRO AF adapter now In Stock!


My order from Aug 23 has also shipped, thanks in large part to this thread,

Is anyone going for the Kolari thin filter for the A7RII? An email arrived with the following link,

http://kolarivision.com/product/sony-a7-series-thin-filter-legacy-lens-upgrade/

I wonder what the downside for Sony FE lenses would be on an A7RII



Sep 01, 2016 at 11:54 AM
genji
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p.27 #9 · p.27 #9 · Techart PRO AF adapter now In Stock!


Hahah! I have the CV 2.5/75 too! It should be great with the Techart. I also ordered Leicaist C/Y to M and OM to M adapters because I have high hopes for autofocusing the OM 85/2 and the C/Y 85/2.8. But the main reason I bought the Techart is to add AF to a bunch of vintage LTM 50mm lenses.

DavidBM wrote:
Yep, I too (also a sydney address) got a shipping notification from TechArt! About a week in my case. Very exciting! The tiny CV 2.5/75 (poor mans summarit) will be fun for portraits...




Sep 01, 2016 at 11:58 AM
DavidBM
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p.27 #10 · p.27 #10 · Techart PRO AF adapter now In Stock!



Snap! I've ordered the k&f om and c/y to M adapters as well (as far as I can tell they will fit TechArt and much cheaper than Leicaist, but if they don't...)

For me on the OM side it's on 3.5/28, a few fifties, and a rare late 3.5/135 (the only production run of tiny 135 that was ever multi coated). And on the c/y side it's 3.5/100 and 35-70. If it all works well I'm tempted for pure sentimentality to get some of the OM lenses I loved the most from my film days (3.5/21, 2/28, 2/50, 2/90) but great lenses though some of these are it doesn't make much sense except for the fun of it...

genji wrote:
Hahah! I have the CV 2.5/75 too! It should be great with the Techart. I also ordered Leicaist C/Y to M and OM to M adapters because I have high hopes for autofocusing the OM 85/2 and the C/Y 85/2.8. But the main reason I bought the Techart is to add AF to a bunch of vintage LTM 50mm lenses.





Sep 01, 2016 at 12:25 PM
 

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bluloo
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p.27 #11 · p.27 #11 · Techart PRO AF adapter now In Stock!


genji wrote:
For anyone wondering how long they might have to wait for a Techart PRO ordered from the manufacturer, I received an email this evening with the subject line:

Your TECHART PRO order from August 21, 2016 is SHIPPED

There's only a two hour difference between Hong Kong and Sydney, so the adapter was shipped 11 days after I ordered it.


Received the same notice.
My order was also close to two weeks - but to ship dumb adapters that were listed as "in stock" when ordered.
They must be really busy.



Sep 01, 2016 at 02:13 PM
arduluth
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p.27 #12 · p.27 #12 · Techart PRO AF adapter now In Stock!


jankap wrote:
But what is the reason for this? In the vertical direction there are sensor points too, I suppose.
Is the reason, that the vertical dimension of the sensor is less (24mm)?
Jan

Perhaps the programmer of the camera software thinks in one direction only?


It's a matter of the algorithms being used to get fast AF. CMOS sensors lack a global shutter - data is read row-by-row. I can't remember all the numbers now, but readout time on a lot of the Sony FF, APS-C, and MFT sensors is ~1/13 sec. The sensor in the A7S/A7SII has a readout speed of ~1/30, which is faster than most.

If it takes 1/13s to fully read from the sensor, why doesn't AF always take at least 1/13s? Because the CDAF system is using that data, row-by-row as it's read. I'd wager there's some row skipping on the first pass. The CDAF system uses the information in adjacent rows, but it can't see into the future. Speed is achieved by making a best guess as to when you've hit focus on that point. There's a balance between focus errors caused by these optimizations and reliable accuracy.

Imagine doing a cross-word puzzle as fast as you can while being limiting yourself to scanning rows for words, left to right. You'll be able to recognize horizontal words more quickly and reliably than vertical words. You're still able to find vertical words, but it'll require more time and be a bit more error prone - the latter because your algorithm might make assumptions about the beginnings of words to speed things up.

This is a best guess informed by working with and programming embedded systems, as well as observing camera behavior.

EDIT: @darrellc managed to explain much more succinctly. Story of my life. :P



Sep 01, 2016 at 02:47 PM
Chad Wadsworth
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p.27 #13 · p.27 #13 · Techart PRO AF adapter now In Stock!


I have both K&F adapters you mention below and they are excellent on the Techart Pro (TAP). K&F are making a nice product at a good price point.

I had ordered a Fotodiox OM to M adapter and returned it immediately due to the sloppy fit - it was so bad that I had light leaks. The K&F is nice and snug.

I'm using the OM 50/1.8 and the 21/3.5 with nice results.

DavidBM wrote:
Snap! I've ordered the k&f om and c/y to M adapters as well (as far as I can tell they will fit TechArt and much cheaper than Leicaist, but if they don't...)

For me on the OM side it's on 3.5/28, a few fifties, and a rare late 3.5/135 (the only production run of tiny 135 that was ever multi coated). And on the c/y side it's 3.5/100 and 35-70. If it all works well I'm tempted for pure sentimentality to get some of the OM lenses I loved the most from my film days (3.5/21, 2/28, 2/50, 2/90) but great
...Show more



Sep 01, 2016 at 04:36 PM
ecarlino
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p.27 #14 · p.27 #14 · Techart PRO AF adapter now In Stock!


GMPhotography wrote:
Remember focus is best achieved on vertical lines and not horizontal. Always look for a vertical contrast spot to get the best focus. This really is how Sonys work best


jankap wrote:
But what is the reason for this? In the vertical direction there are sensor points too, I suppose.
Is the reason, that the vertical dimension of the sensor is less (24mm)?
Jan


The Nikon Phase-Detect module with 51 AF points has 15 points that are "cross-type sensors" to be able to detect contrast in both vertical and horizontal lines. I believe these are concentrated in the center of the frame.

I think none of the Sony On-Sensor Phase Detect AF points are "cross-type" and therefore only capable of detecting "vertical" contrast (with the camera in landscape orientation).

I am unsure of the Contrast Detect algorithm, but it's likely that it's reading row by row, left to right so it also is only detecting vertical contrast - but i haven't seen any details on that algo.



Sep 01, 2016 at 04:54 PM
GMPhotography
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p.27 #15 · p.27 #15 · Techart PRO AF adapter now In Stock!


I'm shooting product today and some issues. Twice now everything dies and once just went from manual to AF on its own. The dying one is weird I mean full dead . Have to power off than on.

I'm in a controlled shooting too. Studio

So rule of thumb for me carry my Fotosy adapter which I have with me. Not good



Sep 01, 2016 at 05:55 PM
k-h.a.w
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p.27 #16 · p.27 #16 · Techart PRO AF adapter now In Stock!


Guy, no surprise here. We are all beta testers.

K-H.

Edited on Sep 01, 2016 at 06:09 PM · View previous versions



Sep 01, 2016 at 06:08 PM
bluloo
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p.27 #17 · p.27 #17 · Techart PRO AF adapter now In Stock!


GMPhotography wrote:
I'm shooting product today and some issues. Twice now everything dies and once just went from manual to AF on its own. The dying one is weird I mean full dead . Have to power off than on.

I'm in a controlled shooting too. Studio

So rule of thumb for me carry my Fotosy adapter which I have with me. Not good


They dying issue isn't uncommon, though it doesn't seem to occur all that often during use.
Yes, it's a pita, and potentially rage-inducing should you miss that once-in-a-lifetime-shot. Hopefully fixable in a coming FW update.




Sep 01, 2016 at 06:08 PM
GMPhotography
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p.27 #18 · p.27 #18 · Techart PRO AF adapter now In Stock!


Yea just did not know if others are reporting this. It's not critical today luckily . Been a beta tester so long I don't know what normal is. Lol


Sep 01, 2016 at 06:21 PM
k-h.a.w
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p.27 #19 · p.27 #19 · Techart PRO AF adapter now In Stock!


Guy, relying on the TAP for a time-critical shoot to me seems like a recipe for disaster.
I like and use the TAP a lot, but that's for having fun with special lenses.

K-H.



Sep 01, 2016 at 06:37 PM
naturephoto1
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p.27 #20 · p.27 #20 · Techart PRO AF adapter now In Stock!


k-h.a.w wrote:
Guy, relying on the TAP for a time-critical shoot to me seems like a recipe for disaster.
I like and use the TAP a lot, but that's for having fun with special lenses.

K-H.


If you remember Paul and Phigment Technology and the Leica M to Sony NEX adapter, Paul had enough issues with the adapter, the electical connections, and failures between the adapters and the cameras that he finally decided to stop the manufacture and support of the adapters after running out of sufficient parts. Hopefully this will not be the case with the TAP adapter.

Rich



Sep 01, 2016 at 06:46 PM
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