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10-13-2014, 09:22 AM   #1
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Takumar 28mm on A7R

I'm thinking of buying a SMC Takumar 28mm. I will use it on my K5 but have pretty much committed to upgrading to an A7/A7R next year and wondered if anyone has experience of this lens on the A7/A7R?? I have read on some forums that the corners are not great so would be interested in anyone's experience :-)

10-13-2014, 10:46 AM - 1 Like   #2
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I don't have an A7, but have used the lens on a 20mp full frame. This is a crop of a corner at F8. It does alright.
10-13-2014, 11:44 AM   #3
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Holy cow! Is that like a 2000% crop?
10-13-2014, 11:49 AM   #4
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QuoteOriginally posted by 6BQ5 Quote
Holy cow! Is that like a 2000% crop?
You want to see pixels or not? It's a very small corner of the photo showing that the lens resolves as well as the aa filter. I got the FF largely to test old lenses in their natural environment.

10-13-2014, 11:52 AM   #5
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QuoteOriginally posted by clicksworth Quote
You want to see pixels or not? It's a very small corner of the photo showing that the lens resolves as well as the aa filter. I got the FF largely to test old lenses in their natural environment.
Me, personally, no. I'd rather see the whole picture.

Good point though on showing how the AA filter works though. I hadn't thought of that.
10-14-2014, 01:49 AM   #6
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cheers for the reply. Good to know it works on FF

I think I'd have bought the lens anyway to use on my K5 but nice to use it on both cameras :-)
10-14-2014, 08:44 PM   #7
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I find that it gets rather dark around the edges when wide open. The effect varies with aperture and is good for keeping the sky blue at mid openings.




10-19-2014, 10:38 AM   #8
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i tested several 28mm lenses on the a7r, and the lowly pentax-m 28/3.5 had some of the cleanest sides, so it's what i use for landscapes these days.

wide glass on the a7r really shows the field curvature problems with lenses.

28mm lens comparison, on the Sony a7R

here is the pentax-m 28/3.5 on the a7r, at f/8... in general, i found that pentax legacy 28mm primes are better than what canon, minolta, and konica was making back in the day.

the problem with a lot of those legacy 28mm primes is that they only have five aperture blades, so they aren't the best choices for bokeh shots:

10-20-2014, 02:21 AM   #9
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QuoteOriginally posted by clicksworth Quote
I find that it gets rather dark around the edges when wide open. The effect varies with aperture and is good for keeping the sky blue at mid openings.

I see what you mean. Seems to vignette quite a bit.

---------- Post added 10-20-14 at 10:27 AM ----------

QuoteOriginally posted by osv Quote
i tested several 28mm lenses on the a7r, and the lowly pentax-m 28/3.5 had some of the cleanest sides, so it's what i use for landscapes these days.

wide glass on the a7r really shows the field curvature problems with lenses.

28mm lens comparison, on the Sony a7R

here is the pentax-m 28/3.5 on the a7r, at f/8... in general, i found that pentax legacy 28mm primes are better than what canon, minolta, and konica was making back in the day.

the problem with a lot of those legacy 28mm primes is that they only have five aperture blades, so they aren't the best choices for bokeh shots:


Looks pretty good. Does it work wide open or have the same vignette issues like the Super Tak? To be honest I can't see myself shooting 28mm wide open, but good nice to know in advance if the lens has any drawbacks.
10-20-2014, 05:12 AM - 1 Like   #10
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QuoteOriginally posted by osv Quote
i found that pentax legacy 28mm primes are better than what canon, minolta, and konica was making back in the day.
Probably because of their longer registration distance, which doesn't cause issues with the microlens array.
10-20-2014, 10:07 AM   #11
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QuoteOriginally posted by mde1970 Quote
Looks pretty good. Does it work wide open or have the same vignette issues like the Super Tak? To be honest I can't see myself shooting 28mm wide open, but good nice to know in advance if the lens has any drawbacks.
i measured the vignetting:

SMC Pentax-M 28mm f/3.5 at f/3.5: -3.34 (f-stops)
Vivitar(Kiron) 28mm f/2.0 at f/4: -2.69 (f-stops)

it's probably a bit worse than a 28/2.8, but they should be pretty similar by f/8.

i with you there, i want one of those faster pentax 28's instead, but they can be kinda pricey.
10-21-2014, 10:11 AM   #12
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QuoteOriginally posted by clicksworth Quote
I find that it gets rather dark around the edges when wide open. The effect varies with aperture and is good for keeping the sky blue at mid openings.
Way back when, wide open performance wasn't such a big deal. People didn't shoot their lenses wide open that often, they wanted everything in focus and tended to bring tripods more often than we do. It was more for focusing and bright viewfinder picture.

Also, 35mm was the "wide angle" back then, 28mm was a superwide, and 20/24mm were the ultrawides. The more "exotic" a lens is in terms of features, the less you tend to care about pure wide-open performance. You're just glad to have a lens that can do what you want...

On lenschat, I was never that impressed with my SMC-M 28/2.8 even on film. I found it to be somewhat low-contrast wide open, and often rather flare prone. It did the job, but nothing to write home about. Nowadays I prefer to reach for my P67 55/4 if I want 28mm FoV. If I can get away with a 35mm and don't need a superfast lens, the 35/3.5 cannot be beat. Crazy sharp and contrasty right from wide open, and plays well with digital sensors. Discontinuing it in 35mm was a Dumb Idea, and it lived on in the "professional" 6x7 series as the 75mm f/4.5 until the system was discontinued around 2000.

If you're going to spend big bucks for a manual focus lens, the Samyang 35/1.4 is excellent value for the money. You can often pick them up used for about $325 and they meet or beat the performance of the Canon/Nikon 35/1.4s, so you will be able to make good use of that high-resolution sensor. The Samyang 24/1.4 is great value too. If you're interested in shooting rather than collecting, I think these options make the Takumar/Pentax 35/2s a poor choice these days, the 35/2s (understandably) don't match the wide-open performance of a modern lens, they're more expensive than a 35/3.5, and if they were cheaper I'd probably still prefer the 35/3.5's great performance.

Last edited by Paul MaudDib; 10-21-2014 at 10:27 AM.
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