23mm closeup focusing issues

[MrPolite]

I just got the 23mm f1.4 and I noticed that if I shoot closeup of white text against black background there is a purple glow to the white text and it's not super sharp at center. I'm shooting wide open and very close to the minimum focus distance. I can focus fine with MF however and there is no purple glow (I feel like AF back-focuses). I'm posting here to see if others with the 23mm have had any AF issues when shooting close to min focus distance? debating whether I should send the lens back for replacement, but if it's a common issue then the next lens might as well have similar problems.

 

Also oddly, while in AF if I get as close to the subject as possible then switch to MF, the lens is out of focus at minimum distance. I have to step back about an inch before minimum MF range is in focus compared to minimum AF range. Doesn't make sense why the minimum focus distance is different between AF and MF modes. Thoughts?

[Merde]

I'm shooting wide open and very close to the minimum focus distance. I can focus fine with MF however and there is no purple glow (I feel like AF back-focuses).

 

My guess is that even though your camera confirms AF lock in reality you are closer than MFD.

[MrPolite]

My guess is that even though your camera confirms AF lock in reality you are closer than MFD.

I thought so too, but I've tried finding the minimum focusable AF distance and looking at the close-up with focus-assist, it looks relatively clear. Switching to MF and going to MFD, everything is considerably blurry... can someone else try this on their 23mm?

 

Also here's a 50% crop of the MF vs AF I just tried

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[Merde]

Still looks like not-quite-in-focus to me.

I cannot help you as I don't own this lens.

[MrPolite]

thanks I think I'll just return the lens for a replacement, as the AF picture on the left is even a few inches further away from the MFD range... just wish Fuji had the ability to do focus tuning like some of the other big names do

[MrPolite]

Just as a FYI for those who may be interested in testing lenses, I found this pretty helpful. http://www.lensrentals.com/blog/2010/11/how-to-test-a-lens

 

Ignorance is however bliss, and maybe not testing your existing lenses is a better idea - I test my 23mm since I still have an opportunity to exchange it. Not sure how accurate my tests are or how much of this really matters in real life. I compared the 23mm auto focus to my other lenses. Focus spot was always narrow area on the '5' text and I tested each several times for consistent results. Some of my other lenses are slightly off too but the 23mm is the worst:

 

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[frod]

thanks I think I'll just return the lens for a replacement, as the AF picture on the left is even a few inches further away from the MFD range... just wish Fuji had the ability to do focus tuning like some of the other big names do

Focus tuning is not relevant when we focus on the sensor, just as it isn't for live view on a dslr. It seems more like your AF or camera-> lens electrical connections could be faulty, or maybe something impairing the sensor?

[MrPolite]

Focus tuning is not relevant when we focus on the sensor, just as it isn't for live view on a dslr. It seems more like your AF or camera-> lens electrical connections could be faulty, or maybe something impairing the sensor?

good point ... as for camera itself, I have to send it for repairs soon since there are hot pixels on the sensor, so maybe I'll ask them to check AF as well, thanks for pointing that out