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romans001
Joined: 06 Aug 2013 Posts: 41 Location: Slovakia
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Posted: Fri Aug 16, 2013 7:33 pm Post subject: Help!-1Day Old 14mm Samyang |
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romans001 wrote:
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! |
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bernhardas
Joined: 01 Jan 2013 Posts: 1432
Expire: 2017-05-23
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Posted: Fri Aug 16, 2013 7:41 pm Post subject: |
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bernhardas wrote:
edited
Last edited by bernhardas on Thu Apr 28, 2016 1:48 pm; edited 1 time in total |
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iangreenhalgh1
Joined: 18 Mar 2011 Posts: 15679
Expire: 2014-01-07
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Posted: Fri Aug 16, 2013 7:46 pm Post subject: |
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iangreenhalgh1 wrote:
I agree with Bernhard, f22 you will have some diffraction for sure. Try f8 and check focus carefully, I strongly suspect your Samyang focuses slightly past infinity and that is the cause of your problem. Many lenses go slightly past infinity so it's not faulty. _________________ I don't care who designed it, who made it or what country it comes from - I just enjoy using it! |
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romans001
Joined: 06 Aug 2013 Posts: 41 Location: Slovakia
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Posted: Fri Aug 16, 2013 7:46 pm Post subject: |
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romans001 wrote:
bernhardas wrote: |
At 22 the lens might not be at its sharpest. Also diffraction kicks in. But that should affect both lenses .
I would try at 5.6 and 8.
Also try nearer focus not infinity.
The weather like haze dust or hot air raising from the ground might affect the picture at long distances (air perspective). |
thank you! i will do retest with f8. I tried focusing not to infinity, nearer also but best output was with infinity focus for this hills. I will try again
but can you say from this images if this performance is ok for this lens? at f22 for now |
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romans001
Joined: 06 Aug 2013 Posts: 41 Location: Slovakia
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Posted: Fri Aug 16, 2013 7:47 pm Post subject: |
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romans001 wrote:
iangreenhalgh1 wrote: |
I agree with Bernhard, f22 you will have some diffraction for sure. Try f8 and check focus carefully, I strongly suspect your Samyang focuses slightly past infinity and that is the cause of your problem. Many lenses go slightly past infinity so it's not faulty. |
will try it again, but i double checked live view for correct focus, i tried near infinity, not maximum, but this was best i can achieve |
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iangreenhalgh1
Joined: 18 Mar 2011 Posts: 15679
Expire: 2014-01-07
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Posted: Fri Aug 16, 2013 7:51 pm Post subject: |
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iangreenhalgh1 wrote:
f22 on APS-C is definitely giving you diffraction. Show us again at f8 and we can give you a better opinion.
If it's not much better, then you have a faulty one and should get it replaced. _________________ I don't care who designed it, who made it or what country it comes from - I just enjoy using it! |
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poilu
Joined: 26 Aug 2007 Posts: 10472 Location: Greece
Expire: 2019-08-29
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Posted: Fri Aug 16, 2013 8:18 pm Post subject: |
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poilu wrote:
the samyang is very sharp, mine was going past infinity, I had to use the 3m mark for infinity
if you cannot get any better even with liveview you probably need to adjust infinity
check 2nd page for the method http://forum.mflenses.com/first-walk-with-samyang-142-8-on-5dii-t50565.html _________________ T* |
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romans001
Joined: 06 Aug 2013 Posts: 41 Location: Slovakia
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Posted: Fri Aug 16, 2013 8:31 pm Post subject: |
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romans001 wrote:
thanks people, i will do some tests tomorrow again (11pm here right now) and will post here results, hopefully images will be sharper. |
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iangreenhalgh1
Joined: 18 Mar 2011 Posts: 15679
Expire: 2014-01-07
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Posted: Fri Aug 16, 2013 8:35 pm Post subject: |
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iangreenhalgh1 wrote:
Good luck! _________________ I don't care who designed it, who made it or what country it comes from - I just enjoy using it! |
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eddieitman
Joined: 12 Apr 2011 Posts: 1246 Location: United Kingdom
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Posted: Fri Aug 16, 2013 8:55 pm Post subject: |
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eddieitman wrote:
I have this lens and can confirm it does go over infinity by a bit, I think my infinity is like 10m and F8 is the sweet spot on the Samyang _________________ My web site www.digital-darkroom.weebly.com
Life is like a camera. Focus on what's important, capture the good times, develop from the negatives and if things don't work out, just take another shot. |
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romans001
Joined: 06 Aug 2013 Posts: 41 Location: Slovakia
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Posted: Fri Aug 16, 2013 9:08 pm Post subject: |
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romans001 wrote:
eddieitman wrote: |
I have this lens and can confirm it does go over infinity by a bit, I think my infinity is like 10m and F8 is the sweet spot on the Samyang |
hopefully i could be able to find this sweet spot too will try again |
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fuzzywuzzy
Joined: 18 Dec 2010 Posts: 1258 Location: Down East, Canada, eh?
Expire: 2013-11-30
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Posted: Fri Aug 16, 2013 10:07 pm Post subject: |
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fuzzywuzzy wrote:
Check your infinity focus with the lens wide open, then stop down.
Here's an article about diffraction, with a calculator to help you determine the point at which stopping down will start reducing sharpness for your body.
http://www.cambridgeincolour.com/tutorials/diffraction-photography.htm _________________ I welcome C&C, editing my pics and reposting them on the forum is fine.
NEX-F3
~~~~~~~~~
CZJ Sonnar 135/4, Biotar 58/2, Pancolar 50/2, Tessar 50/2.8, Flek 35/2.8, Flek 25/4
Super Takumar 135/2.5, 135/3.5, 100/4 bellows, 50/1.4, 28/3.5
Helios 58/2, 3M-5A 500/8, Mir 20M
Vivitar Series 1 70-210 - - - - - - - - Nikkor 200/4
Rikenon 28/2.8 - - - - - - - - Zeiss 50/1.7 Planar
PB 50/2.4, 135/2.8
Yashica 50/1.9, 28/2.8, 135/2.8
Hexanon 28/3.5, 50/1.4 |
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sichko
Joined: 20 Jun 2008 Posts: 2475 Location: South West UK
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Posted: Fri Aug 16, 2013 10:49 pm Post subject: |
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sichko wrote:
Reduction in sharpness due to diffraction depends upon the lens f-number and the wavelength of light. It doesn't depend upon the camera body. _________________ John |
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fuzzywuzzy
Joined: 18 Dec 2010 Posts: 1258 Location: Down East, Canada, eh?
Expire: 2013-11-30
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Posted: Fri Aug 16, 2013 11:10 pm Post subject: |
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fuzzywuzzy wrote:
sichko wrote: |
Reduction in sharpness due to diffraction depends upon the lens f-number and the wavelength of light. It doesn't depend upon the camera body. |
How many megapixels is a factor, crop factor is a factor, smaller pixels = more sensitive to diffraction. _________________ I welcome C&C, editing my pics and reposting them on the forum is fine.
NEX-F3
~~~~~~~~~
CZJ Sonnar 135/4, Biotar 58/2, Pancolar 50/2, Tessar 50/2.8, Flek 35/2.8, Flek 25/4
Super Takumar 135/2.5, 135/3.5, 100/4 bellows, 50/1.4, 28/3.5
Helios 58/2, 3M-5A 500/8, Mir 20M
Vivitar Series 1 70-210 - - - - - - - - Nikkor 200/4
Rikenon 28/2.8 - - - - - - - - Zeiss 50/1.7 Planar
PB 50/2.4, 135/2.8
Yashica 50/1.9, 28/2.8, 135/2.8
Hexanon 28/3.5, 50/1.4 |
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sichko
Joined: 20 Jun 2008 Posts: 2475 Location: South West UK
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Posted: Sat Aug 17, 2013 4:55 pm Post subject: |
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sichko wrote:
fuzzywuzzy wrote: |
sichko wrote: |
Reduction in sharpness due to diffraction depends upon the lens f-number and the wavelength of light. It doesn't depend upon the camera body. |
How many megapixels is a factor, crop factor is a factor, smaller pixels = more sensitive to diffraction. |
Really ? Then what about this statement ...
Diffraction thus sets a fundamental resolution limit that is independent of the number of megapixels, or the size of the film format. It depends only on the f-number of your lens, and on the wavelength of light being imaged.
These words match my understanding but they are taken directly from the first page of the Cambridge in Colour link you provided. Then McHugh (the CiC owner) goes on to talk about diffraction limited cameras. I haven't a clue what he's talking about. It looks like nonsense to me. Can you - or anyone - help ? _________________ John |
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Aanything
Joined: 27 Aug 2011 Posts: 2187 Location: Piacenza, Italy
Expire: 2014-05-30
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Posted: Sat Aug 17, 2013 5:02 pm Post subject: |
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Aanything wrote:
sichko wrote: |
fuzzywuzzy wrote: |
sichko wrote: |
Reduction in sharpness due to diffraction depends upon the lens f-number and the wavelength of light. It doesn't depend upon the camera body. |
How many megapixels is a factor, crop factor is a factor, smaller pixels = more sensitive to diffraction. |
Really ? Then what about this statement ...
Diffraction thus sets a fundamental resolution limit that is independent of the number of megapixels, or the size of the film format. It depends only on the f-number of your lens, and on the wavelength of light being imaged.
These words match my understanding but they are taken directly from the first page of the Cambridge in Colour link you provided. Then McHugh (the CiC owner) goes on to talk about diffraction limited cameras. I haven't a clue what he's talking about. It looks like nonsense to me. Can you - or anyone - help ? |
I'm not an expert, but what I understood reading that is that diffraction happens according to f number, but this loss of resolution is perceived according to the pixel pitch. _________________ C&C and editing of my pics are always welcome
Samples from my lenses
My gear
My Flickr |
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hifisapi
Joined: 25 Sep 2012 Posts: 941 Location: USA
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Posted: Sat Aug 17, 2013 8:10 pm Post subject: |
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hifisapi wrote:
diffraction is more noticeable on small formats or higher pixel pitch sensors. _________________ ===========
ACQUIRED OVER 30 YEARS:
Cameras: DSLR=Pentax istDS FILM=Pentax SP, SP-F, ESII, SP1000, KX, K2
Lenses : Pentax M42 = Super Multi Coated Takumars 50/1.4 55/1.8 100/4-BELLOWS 500/4.5 1000/8 135-600/6.7 Pentax PK= SMC Pentax-Ks K17/4-FF Fisheye K18/3.5 K20/4 K24/3.5 K28/3.5 K28/2 K35/3.5 K35/2 K50/1.2 K50/1.4K 50/4-MACROK 55/1.8 K85/1.8 K100/4-MACRO K100/4-BELLOWS K105/2.8 K120/2.8 K135/3.5 K135/2.5 K150/4 K200/4 K400/5.6 K45-125/4K 85-210/4.5 Pentax PKM = SMC Pentax-M M40/2.8-Pancake M50/1.4 M75-150/4 M80-200/4.5 Pentax PKA= SMC Pentax-A A15/3.5 A50/2.8-MACRO A28/2 A35/2 A50/1.4 A135/2.8 A200/4 A*300/4 A35-105/3.5 A24-50/4 A70-210/4 TAMRON AD2= SP80-200/2.8 SP180/2.5 TOKINA AT-X PK= ATX28-85/3.5-4.5 ATX35-70/2.8 ATX60-120/2.8 ATX80-200/2.8 ATX100-300/4 ATX90/2.5 MACRO KIRON-LESTER DINE PK = 105/2.8-MACRO VIVITAR PK = 135/2.8-MACRO 28-85/4 NOFLEXAR AUTOBELLOWS PK = 60/4 105/4 |
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iangreenhalgh1
Joined: 18 Mar 2011 Posts: 15679
Expire: 2014-01-07
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Posted: Sat Aug 17, 2013 8:16 pm Post subject: |
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iangreenhalgh1 wrote:
Instead of quoting facts and figures, I think it better to rely on practical experience. On an APS-C sensor with a pixel pitch of around 6 then diffraction is not noticeable until f11, and even then, you have to pixel peep and look closely to see it. Always beware the advice of people who don't post pictures. _________________ I don't care who designed it, who made it or what country it comes from - I just enjoy using it! |
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Aanything
Joined: 27 Aug 2011 Posts: 2187 Location: Piacenza, Italy
Expire: 2014-05-30
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Posted: Sat Aug 17, 2013 8:22 pm Post subject: |
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Aanything wrote:
iangreenhalgh1 wrote: |
Instead of quoting facts and figures, I think it better to rely on practical experience. On an APS-C sensor with a pixel pitch of around 6 then diffraction is not noticeable until f11, and even then, you have to pixel peep and look closely to see it. Always beware the advice of people who don't post pictures. |
I've had 3 16 mp apsc cams so far and all of them showes no perceivable signs of loss of resolution at f11.
Something could be noticed at f16, and at f22 usually is quite evident.
That said, and back to the original topic, the lack of sharpness in the pictures posted seem a bit too much, but it's impossible to state anything without more samples at other apertures. _________________ C&C and editing of my pics are always welcome
Samples from my lenses
My gear
My Flickr |
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iangreenhalgh1
Joined: 18 Mar 2011 Posts: 15679
Expire: 2014-01-07
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Posted: Sat Aug 17, 2013 8:37 pm Post subject: |
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iangreenhalgh1 wrote:
I would agree, you see it at f16, at f11, it's hard to see and not always visible.
I made some shots with an I-61 yesterday at F16, I don't see any lack of sharpness at all, I can see very slight diffraction but my usual sharpening completely overcomes it, making it fair to say that shooting at f16 on a 14mp APS-C sensor like the one in my NEX-3 is perfectly possible.
I agree, the lack of sharpness in this Samyang looks far beyond what diffraction would cause. _________________ I don't care who designed it, who made it or what country it comes from - I just enjoy using it! |
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pdccameras
Joined: 23 Aug 2009 Posts: 825 Location: Putnam, CT
Expire: 2014-08-11
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Posted: Sat Aug 17, 2013 11:20 pm Post subject: |
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pdccameras wrote:
Romans,
I find my Bower version of this lens acceptably sharp. I used Poilu's instructions (brilliant presentation by the way!) to re-set infinity, but I find I usually focus via live view anyway. Here are a few shots with 100% crops from 5D raw files for you. Don't want to hijack your post, but thought you might want a few comparisons. These were taken this evening.
Best,
Paul
Set one:
Set two:
_________________ Canon 5D Mii, Canon 40D, Canon 350D IR, Sony A7 Mii, Sony Alpha-6000, a ton of lenses: AF & MF and too many cameras to count, all formats: 110 - 4x5. |
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iangreenhalgh1
Joined: 18 Mar 2011 Posts: 15679
Expire: 2014-01-07
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Posted: Sun Aug 18, 2013 1:12 am Post subject: |
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iangreenhalgh1 wrote:
Wow, that first shot's a stunner Paul! _________________ I don't care who designed it, who made it or what country it comes from - I just enjoy using it! |
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pdccameras
Joined: 23 Aug 2009 Posts: 825 Location: Putnam, CT
Expire: 2014-08-11
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Posted: Sun Aug 18, 2013 1:50 am Post subject: |
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pdccameras wrote:
Thanks, Ian. I can't take credit for the beauty of Cargil Falls, but the Bower can deliver-even on full frame! The Samyang/Bower images look remarkably similar to those produced by the medium format 30mm Arsat lenses from Arsenal in Russia. I have an almost identical image I made with the Arsat in P6 mount adapted to Pentax 645.
Paul _________________ Canon 5D Mii, Canon 40D, Canon 350D IR, Sony A7 Mii, Sony Alpha-6000, a ton of lenses: AF & MF and too many cameras to count, all formats: 110 - 4x5. |
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iangreenhalgh1
Joined: 18 Mar 2011 Posts: 15679
Expire: 2014-01-07
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Posted: Sun Aug 18, 2013 3:57 am Post subject: |
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iangreenhalgh1 wrote:
I have the Arsat too, you just reminded me I must develop the roll I shot with it! _________________ I don't care who designed it, who made it or what country it comes from - I just enjoy using it! |
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romans001
Joined: 06 Aug 2013 Posts: 41 Location: Slovakia
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Posted: Sun Aug 18, 2013 8:42 am Post subject: |
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romans001 wrote:
yesterday i tested lens again, i think with better results, i used f around 5.6 and live view sharpening. But still, when i am sharpening with liev view i cant see change in sharpness for distant details whenever i used infinity mark or even close but i think its just ok for wide lens.
i will post images today, will see. looking forward to hear your comments. i think i will keep this lens. I though i will change it for some 10-20 sigma or similar but i was happy yesterday with results. |
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