Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
08-16-2013, 12:31 PM   #1
Veteran Member
romansolar's Avatar

Join Date: Jun 2012
Location: Kosice,Slovakia
Photos: Gallery | Albums
Posts: 438
Help!-1Day Old 14mm Samyang

hi folks

i bought samyang 14mm prime. Brand new manual lens. I saw great reviews and also on lens review this prime has very solid reputation

but i thought this lens will produce sharp images, maybe i am wrong, please no offense, i went outside and try few shots with my k01. I used m28mm prime pentax old lens, and also this samyang.

f22, tripod, same spot and time. Focus checked with live view.

Here you can see full images directly from camera. In camera settings for sharpness: +1\

is this ok? i mean i though images will be much sharper please i need advice, this is common output or should i return it?

pentax m28mm



samyang 14mm



100%crop pentax



100%crop samyang



samyang left part | pentax right part



thx!

08-16-2013, 12:34 PM   #2
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 42,352
The problem is you're shooting at f22. At such a wide focal length, the diffraction will be pretty severe. Set your lens to f8 or f11 for optimal sharpness.

Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)



PentaxForums.com's high server and development costs are user-supported. You can help cover those costs by donating. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

08-16-2013, 12:43 PM   #3
Veteran Member
romansolar's Avatar

Join Date: Jun 2012
Location: Kosice,Slovakia
Photos: Gallery | Albums
Posts: 438
Original Poster
thank you Adam! i will do retest with f8

but for this output, looks fine? can you say from this pictures if its ok performance?
08-16-2013, 01:16 PM   #4
Loyal Site Supporter
THoog's Avatar

Join Date: Aug 2012
Location: North Carolina
Photos: Gallery | Albums
Posts: 3,484
Do you have Shake Reduction turned on, and if so, is the focal length set to match the lens? If the focal length setting is not correct, SR can actually introduce some blurring and make the lens look "soft".

08-16-2013, 01:33 PM   #5
Veteran Member
romansolar's Avatar

Join Date: Jun 2012
Location: Kosice,Slovakia
Photos: Gallery | Albums
Posts: 438
Original Poster
QuoteOriginally posted by THoog Quote
Do you have Shake Reduction turned on, and if so, is the focal length set to match the lens? If the focal length setting is not correct, SR can actually introduce some blurring and make the lens look "soft".
yes, SR is on, focal length was set to 12 because there is no 13 or 14 on my k01, do you think this could be problem? thank you!
08-16-2013, 01:42 PM   #6
Junior Member
topher's Avatar

Join Date: Aug 2009
Location: Central Pennsylvania
Posts: 31
QuoteOriginally posted by romansolar Quote
yes, SR is on, focal length was set to 12 because there is no 13 or 14 on my k01, do you think this could be problem? thank you!
You might try it with SR turned off since you are using a tripod.
08-16-2013, 02:06 PM   #7
Veteran Member
romansolar's Avatar

Join Date: Jun 2012
Location: Kosice,Slovakia
Photos: Gallery | Albums
Posts: 438
Original Poster
thanks! will do it again without sr
08-16-2013, 02:16 PM   #8
Pentaxian




Join Date: Jun 2009
Location: GMT +10
Photos: Albums
Posts: 10,756
As everyone has said:

- set aperture to f5.6 or f8.
- turn SR off
- make sure no light is hitting the lens directly.

You may also find the following comment from photozone useful:

QuoteQuote:
"Infinity focus is actually way "beyond" infinity - at least on our test sample. Consequently the initial field attempts were pretty bad but during our 2nd session we used settings at slightly less than 2m (which is a good idea anyway) for wide, open scenes and the results improved drastically."
As you can see from the lenstip.com test of the lens, it is at it's softest at f22 on both full-frame and APS-C...best to stay away from shooting at f22

Attached Images
 
08-16-2013, 02:20 PM   #9
Veteran Member
demp10's Avatar

Join Date: Jun 2011
Location: Atlanta
Photos: Albums
Posts: 602
As mentioned, when on tripod SR MUST be off, and F22 is way too small and will introduce image quality loss due to diffraction. The optimum F-stop for that lens is F5.6 or F8, although it is very sharp at F2.8 also.

When you check focus you must zoom in 6X or 8X to see the details. The DOF is great, but if you nail focus it will be sharper. It is next to impossible to tell focus if you are viewing the entire frame.

Many copies of this lens (mine included) are not correctly calibrated in the distance scale. Infinity focus on mine is at 2m. You can do an experiment at F2.8, camera on tripod (SR off) and shoot a series of a far distant sharp-edged object at various distance settings on the lens. Then compare the results and find the sharpest. That will be your infinity mark. You can set the lens at that and F8 and never wary about focusing for landscapes again.

You will get much better results if you shoot RAW and then in post-processing increase clarity and sharpness.
08-16-2013, 04:35 PM   #10
Pentaxian
Na Horuk's Avatar

Join Date: Feb 2012
Location: Slovenia, probably
Photos: Gallery | Albums
Posts: 10,764
I also have that lens. It is really hard to focus on the K-01, because the display looks sharp constantly. Focus peaking helps only when you are focusing very near. So here are my tips:
If you have a tripod, use 2 sec timer for landscape photos. (this goes for all lenses. 2 sec timer also disables SR. SR is useless and can even be bad on a tripod) Keep aperture under f16, around f8 or so. DoF is pretty big either way, even at f4.0.
For focusing, use the digital zoom to help you find the sweet spot. You can try zone focusing, but dont rely on the distance scales on the lens - they are mostly wrong. And the lens might not be focusing on the same distance, depending on whether you focus to it from infinity or from near.

Another thing to remember is that this is ultra wide. Its not going to give you sharpness like a 50mm, and you cant just enlarge the photo and expect it to look as if it were taken with a longer lens. This lens definitely takes some getting used to, to learn how to operate it, how to compose photos, and even how to process the photos. I shoot raw and bump the sharpness up to 40 and above (from the default 25). Radius of 0.6 or so.

There are also some blog posts and threads online that show you how to calibrate/fix your focus ring on that lens, so it will be more accurate. You can try that if you want, I personally havent bothered (yet)

The only thing I suggest you check is for lens decentering - make sure its equally sharp all across the frame. And then take a photo at closest focus, of a book placed at an angle, to check how sharp the lens really is (because the DoF will be clearly visible at near focusing, so you can tell apart what is OoF vs. what should be in focus and sharp). Relax, uwa lenses simply have a lot of distortion, more CA, flare very easily, and are not quite as sharp as normal lenses (35-60mm). And resolution is limited by the camera, so there is only so much detail it can record. The Samyang is not a bad lens, but it certainly has its weaknesses and takes a lot of getting used to. Check out the link in my sig and scroll down, there should be quite a few test photos I took of forests with the Samyang 14mm. These are very much processed and sharpened up.

Good luck.

Last edited by Na Horuk; 08-16-2013 at 04:42 PM.
08-16-2013, 10:18 PM   #11
Site Supporter




Join Date: Jul 2011
Location: Auckland, New Zealand.
Posts: 328
Hi Roman all the above rings true.
May I suggest that you compare image heights when comparing one lens against the other.
I use a sheet of newspaper and shoot with my favorite 50 set at it's best f stop as a comparison shot
Before moving anything or changing lenses I also mark where the corners of the viewfinder just show on the paper.
Now put on the Samyang 14mm and set to f5.6.
Move tripod closer to newspaper until it fills the frame exactly the same as it did in the first shot and use live view/ focus peaking to get best focusing and take shot.
Before you move anything check distance to newspaper to sensor plane with a tape measure and compare what lens is set to for reference.
I have found the Samyang 14mm to be very sharp when compare to other lenses when comparing the same size image heights.

Hope this helps, Chris.
08-16-2013, 11:22 PM   #12
Veteran Member
romansolar's Avatar

Join Date: Jun 2012
Location: Kosice,Slovakia
Photos: Gallery | Albums
Posts: 438
Original Poster
firstly, thank you all for help! much appreciate, i will try today again shooting outdoor, will post results soon


QuoteOriginally posted by ak_kiwi Quote
Hi Roman all the above rings true.
Before you move anything check distance to newspaper to sensor plane with a tape measure and compare what lens is set to for reference.
, Chris.
thanks Chris, i could do that, but what do you mean with above sentence? i dont understand it

thanks all!
08-17-2013, 01:00 PM   #13
Site Supporter




Join Date: Jul 2011
Location: Auckland, New Zealand.
Posts: 328
Lowell Goudge in a earlier thread suggested that the distance scales marked on the focusing ring and barrel for this lens may actually be for Canon registry distance.
The reason I raise this point is that if use you the distance scale to prefocus the lens it is very likely that you will get an out of focus picture.

Calculating hyper-focal distance for APS-C and setting this lens at f4 results in a 2.46m distance setting. With a tape measure set the camera this distance from the newspaper test subject and focus lens for maximum sharpness.
If you now have a look at what the distance is showing on the lens you will find the scales are somewhat inaccurate.

I have checked hyper-focal distances for various f stops with my lens and written down what the variance is in relation to the markings on the focus-/barrel. I have found this useful to use as a reference point when using prefocus.
08-18-2013, 01:37 AM   #14
Veteran Member
romansolar's Avatar

Join Date: Jun 2012
Location: Kosice,Slovakia
Photos: Gallery | Albums
Posts: 438
Original Poster
thank you all for inputs, yesterday i tested lens again, performed better i think, will post images very soon. I used f around f5.6, focused with live view, k01.
08-18-2013, 11:33 AM   #15
Veteran Member
romansolar's Avatar

Join Date: Jun 2012
Location: Kosice,Slovakia
Photos: Gallery | Albums
Posts: 438
Original Poster
examples, still did not have enough time to properly test different setting as many of you suggested, so hopefully for future, even better images will be produced. I think i will keed this lens, what do you think about following images. no post processing. only camera setting, sharp+1 contrast+1










i like how sharp distant forest looks on picture below, look for horizon, but i dont know, maybe they are so sharp because part of sky right over distat forest is burned, sodont know if the lens is sharp or its just because of contrast due to overexposed part of sky



200% crop



Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
14mm, camera, images, k-mount, lens, m28mm, pentax, pentax lens, samyang, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Soft lens or normal - Samyang 14mm thechumpen Pentax SLR Lens Discussion 28 05-28-2013 07:43 AM
For Sale - Sold: Bower 14mm (aka Vivitar, Samyang, Rokinon) superstan Sold Items 2 12-04-2012 11:28 AM
Wanted - Acquired: Samyang 14mm, Sigma 15mm/f2.8 Turtle Sold Items 3 09-08-2012 05:59 AM
For Sale - Sold: Samyang 14mm 2.8 UWA (Vivitar Branded) joe.penn Sold Items 12 01-17-2012 01:00 PM
For Sale - Sold: Rokinon/Samyang 14mm f/2.8 adpo Sold Items 6 10-14-2011 09:19 AM



All times are GMT -7. The time now is 12:10 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top