Issue(?) with samyang 18mm f2.8

[kookoo_gr]

A couple of months ago i bought for my canon eos 450d a samyang 14mm f2.8 and i am struggling with a halo/comma issue. When i take images at f2.8 even though i am focused i have at the stars a halo/comma which is not uniform at the whole image. If i take images at f4 this issue is not that much visible. The lens is brand new with no visible problems (aka hits) and i use no adaptors for the camera. Also the focusing for this lens is at the 2-3 m mark on the ring rather than infinity is this normal? i would like some opinions on the matter before i return the lens.

 

here is a sample image at 15sec iso800 f2.8

 

 

[Wyvern]

Hi,

Yours seems a common "complaint" on these "lightbucket" lenses.  Better results are found at f4, but stopping any lens down generally improves things as standard. Have a search for this thread here on SGL 

Samyang 14mm - star image quality assessment

Makes for interesting reading.

Les

[Daniel-K]

Loney speck ( https://www.lonelyspeck.com/ ?  had the same problem with one side of the field in focus and the other out of focus. sadly this is poor QC and normally requires a return. 

[kookoo_gr]

I managed to take a few more pictures and i would like your opinion, photos are 15sec iso800 f2.8

[michaelmorris]

Samyang lens are great and the 14mm is renowned for good star shape pretty much right to the edge, even when wide open.  However, quality control is not all it should be and apparently many people have experienced  misaligned optics in lenses they have purchased.  This does sound just like one such case.  I have heard of one person who returned two lenses before the third one was acceptable.  I have the 10mm and (knowing the potential issues) I checked it thoroughly as soon as I bought it.  Mine wasn't perfect, but easily within the tolerances I would find acceptable.