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05-16-2013, 01:16 AM   #1
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Soft lens or normal - Samyang 14mm

Hi all

I bought the 14mm but had heard you often get soft copies. Mine seems to be soft, but then maybe what I am seeing is normal for a wide angle (first one I own).

Here is how I have tested - put a newspaper on a wall. Camera is around 2m away and set on tripod with shutter timer (so SR is off etc). Camera is set to F8. I tried using hyperfocal and DOF charts and couldn't get a sharp picture. I then took a series of pictures with a minor tweak of the focus each time starting at one end of focus and ending at the other, and not one is sharp. They look "OK" when viewed normally but when I zoom in the text on the paper is unreadable due to blur in every single picture.

I then tried the same thing with my DA 35 and even used manual focus still, and when zooming in the text is perfectly sharp.

So question is, does this sound like I need to replace the lens, or is it normal for wide angles to be less sharp?

05-16-2013, 01:35 AM   #2
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Without pictures to show, i believe it'll be hard to tell. But judging from the steps that you have listed down, i believe it is so; your lens is "faulty"..
Others might differ..

:/
05-16-2013, 01:45 AM   #3
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Yeah I planned to post the pictures but could figure out how to export a "zoomed in" picture from Lightroom. I have seen people on here posting zoomed in crops so any tips on how to do that and I will post them.
05-16-2013, 01:56 AM   #4
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QuoteOriginally posted by thechumpen Quote
Yeah I planned to post the pictures but could figure out how to export a "zoomed in" picture from Lightroom. I have seen people on here posting zoomed in crops so any tips on how to do that and I will post them.
In the interim, just post them on your Flicker site?

From what you describe could be you have a faulty lens, but have you tried in-camera AF Fine adjustment?

05-16-2013, 02:45 AM   #5
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I have a 14mm Samyang and its really hard to tell. I think the problem is the hype that you read online. I mean, its sharp, but its not as sharp as a 50mm. And focusing is really not as easy as they like to say it is. I returned one copy and got another that was basically the same. In fact, the second copy has less CA, but also less sharpness in the centre? I'm not sure. But for a test I suggest you do two things:
1) just manually focus the lens into as near as you can. So, the opposite of infinity. And now take a photo of a newspaper, but the newspaper should be at angle, not parallel to the sensor. You will see exactly where the DoF is and you will see how sharp the "sharp" part actually is.
2) Turn off shake reduction, use shutter speed at least as fast as 1/125 and don't count on hyperfocal focusing. Be smart when using "sharpening" in the raw developer. In my case, Lightroom makes it look weird, rather than sharp, until I start fiddling with the sliders. All the amazing photos you see online taken with this lens were sharpened in some way.

What you need to watch out for is decentering (uneven sharpness, CA) and misaligned focus ring (there are some reports that the focus ring numbers are wrong, that infinity on the focus ring isn't actual infinity. There are even some tutorials on how to fix this). And I don't know, sometimes I get good sharp results from this lens, sometimes I get photos where nothing looks sharp, at all, even though I used a high f-stop and hyperfocal..
05-16-2013, 03:16 AM   #6
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OK, doing the newspaper thing close up it is sharp.

However, the reason I bought this was for landscapes and to use hyperfocal distances rather than for close up work. Maybe my understanding of all this is correct but my assumptions are:

1) At F8 my hyperfocal distance (using a DOF calculator) is 1.2m, which means if I focus at 1.2m then everything from 60cm to infinity should be in focus.
2) I know of the reports about the 14mm focus marks not being accurate hence trying lots of different shots with slight tweaks. My assumption is that somewhere I should get the pic in focus, but it never happens.

This is the best I got and if you zoom in then you can see how blurry the text is on the paper:
14mm test shot | Flickr - Photo Sharing!
05-16-2013, 03:53 AM   #7
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QuoteOriginally posted by thechumpen Quote
OK, doing the newspaper thing close up it is sharp.

However, the reason I bought this was for landscapes and to use hyperfocal distances rather than for close up work. Maybe my understanding of all this is correct but my assumptions are:

1) At F8 my hyperfocal distance (using a DOF calculator) is 1.2m, which means if I focus at 1.2m then everything from 60cm to infinity should be in focus.
2) I know of the reports about the 14mm focus marks not being accurate hence trying lots of different shots with slight tweaks. My assumption is that somewhere I should get the pic in focus, but it never happens.

This is the best I got and if you zoom in then you can see how blurry the text is on the paper:
14mm test shot | Flickr - Photo Sharing!
Hi there chumpen,
Ok I have just done the same test as you with my copy of the lens on a K5iis and K5 and have pretty much identical results.
1 question - What was the zoom ratio you where using to view the actual print on the newspaper?

As an aside I also checked the distance scales against measurements from the sensor plane to subject and found the markings to be any where between 10 to 50 percent out.
05-16-2013, 03:56 AM   #8
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Bud, I think I'm in the same boat. Like I said, turn off SR, don't rely on hyperfocal. You can try a test where you take a landscape photo focused at infinity and then more and more away from infinity. Of course, the problem is that the lens can focus beyond infinity.
Hyperfocal is merely "acceptable" focus, not "perfect focus", and it was also developed for film, which has different characteristics from modern digital sensors with high pixel density. Some say you need to use zone focusing at one stop higher aperture, to compensate. I just kind of gave up on zone focusing with this lens and treat it like a regular MF - focusing as near to the object that I want, and then maybe getting more stuff in focus as well.
Also, other UWA lenses cost much, much more and aren't necessarily that much better. The internet hype gives us too big expectations of this lens. Its really not bad for the amount it costs, but it won't beat a 24mm or 50mm Pentax prime in terms of sharpness and build.

05-16-2013, 04:13 AM   #9
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kiwi - I viewed the pics in Lightroom at 3:1 magnification and also on the camera by just zooming as far as it would go. If I do this with my DA 35 I get perfectly sharp text.

Na Horuk - I have it set to a timed shutter, which I believe automatically turns off shake reduction. Also, whilst I tried hyperfocal I found it didn't work then went through the process of taking loads of photos and slight increments in focus ring, thinking that I would find a sharp image in there somewhere. Alas it wasn't to be so.

Would be interested to hear if this is just to be expected for this lens or if some people have one that does give sharp results.

Interestingly I have just tried with my 18-55 set at 18 and this gives pretty much the same thing. Maybe I am just expecting too much and this is normal for a wide angle.
05-16-2013, 11:30 AM   #10
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QuoteOriginally posted by thechumpen Quote
I viewed the pics in Lightroom at 3:1 magnification and also on the camera by just zooming as far as it would go. If I do this with my DA 35 I get perfectly sharp text.
Yes there is not too much wrong with that DA35 and the Samyang 14mm is on par with it I have found.

If you compare same image heights between the two lenses you will see what I mean.
Example - get a ruler and photograph it with both lenses with it just completely filling the frame. View both images at the same magnification and you should have the same image quality.(Unless your copy is indeed a real dud, but from your photo I would not think so)
The trap I fell into with this lens (when using it for the first time just last week) is that I expected it to record scenes with a perspective twice as broad,with the same detail, as my longer lenses.
The result, of course, was an image with half the detail.

Last edited by ak_kiwi; 05-16-2013 at 12:46 PM.
05-16-2013, 01:24 PM   #11
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QuoteOriginally posted by ak_kiwi Quote
Hi there chumpen,
Ok I have just done the same test as you with my copy of the lens on a K5iis and K5 and have pretty much identical results.
1 question - What was the zoom ratio you where using to view the actual print on the newspaper?

As an aside I also checked the distance scales against measurements from the sensor plane to subject and found the markings to be any where between 10 to 50 percent out.
You need to remember that the lens is a full frame lens so hyper focal distances are wrong because the depth of field is different when enlarging from ASp-c and full frame. I have no issues with my 14/2.8 purchased from B&H about 43 years ago now with vivitar markings.

I have used it on my K10 and K7 as well as my PZ1
05-16-2013, 05:24 PM   #12
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QuoteOriginally posted by Lowell Goudge Quote
You need to remember that the lens is a full frame lens so hyper focal distances are wrong because the depth of field is different when enlarging from ASp-c and full frame.
Yes I totally agree. You have to calculate hyperfocal distances based on the crop factor.
I was referring to the focused distance (rather than DOF markings which I don't have on my copy) as marked on the lens barrel which I checked against a measuring tape after manually focusing in live view.
05-16-2013, 05:42 PM   #13
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This probably explains it better - this 2.46m at sharp focus......
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05-16-2013, 05:55 PM   #14
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QuoteOriginally posted by ak_kiwi Quote
This probably explains it better - this 2.46m at sharp focus......
Holy mother of goat! I would say it's a dud!

Send it back!

Last edited by SyncGuy; 05-16-2013 at 06:03 PM.
05-16-2013, 06:48 PM   #15
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QuoteOriginally posted by thechumpen Quote
kiwi - I viewed the pics in Lightroom at 3:1 magnification and also on the camera by just zooming as far as it would go. If I do this with my DA 35 I get perfectly sharp text.
Maybe I misunderstand you, but this test makes no sense. Is your tripod in the same place for the pictures you took for both lenses, or did you move back so that the paper occupied the same amount of the frame when you took the picture with the DA 35, as ak_kiwi is saying? If the tripod didn't move, it's a no-brainer that the DA 35 is sharper: the paper covers more pixels.

Your test shot looks perfectly fine to me. How sharp do you expect it to be? It's a lot more difficult to make a lens as wide as this than it is to make a 35mm. I'd say it's outstanding for the price it sells for.

Here's a shot from mine @f/5.6:



100% crop of the same:



I didn't do any sort of sharpening. Yeah, it's not that sharp when you're pixel-peeping, but you won't find anything better for even close to the same price. Besides, it's the colors and contrast, along with the extremely wide angle, that make me love this lens.
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