I recently picked up a slightly used copy.
Its very sharp in the center, but noticing out past 80% or so of the FOV, the edges are noticeably soft.
This is true before & after lens correction.
I have only notice it when shooting landscape images, but haven't done a thorough test
to see where it goes soft.
I need to find a scene with a range of object distances "around" the scene,
It appears to be OK on the top & bottom. Just an issue, on the L/R sides.
I will also do a focus stacking experiment to see if its distance related
Will post an image later on tonite.
Your copy is definitely below the standard for this lens. Mine only gets that blurry in the very corners of the frames (sides are ok). Yours is not a focusing issue perse but likely one of the elements is out of spec, assuming you're focusing the lens correctly. To be sure, try f/8 and f/11 at hyperfocal.
Here's a full-sized sample from mine, uncorrected for distortion, on a 5DM2:
Wow, what a difference!
Do you remember what f-stop you shot that at
I need to do other f-stops as you mentioned.
I had hoped to use f5.6 for best sharpness!
Do you know anything about service or is it just return it through the selling store?
dswiger wrote:
Wow, what a difference!
Do you remember what f-stop you shot that at
I need to do other f-stops as you mentioned.
Dan
I'm not sure but judging from the shutter speed and lighting conditions I'd say f/8 or f/11. I think sharpness-wise the lens is probably at/near optimal at f/5.6 across the frame. Here's photozone's charts on it:
Yeah, that does not look good at all. I generally shoot mine at f/5.6 and it is very very sharp corner to corner on full frame. The only issue/annoyance with my copy (and apparently many other copies) is that the focus distance markings and infinity stop are way way off.
Due to the cheap mechanics the lens could be tilted.
My Samyang 14mm f/2.8 is at them moment not usabel - because such a misalingment. I think about DIY made a own mount part, to get rid of that plastic.
If you have used my way of register distance correction check the lens again without the washers - these washers need to very accurate!
On my lens the three screws on the outer barrel are not sturdy enough - the hole front could be pulled ~1mm out and pressed again. That was much fun :-/
But if you screw the screws more, the iris stopped working :-/
dswiger wrote:
I recently picked up a slightly used copy.
Its very sharp in the center, but noticing out past 80% or so of the FOV, the edges are noticeably soft.
This is true before & after lens correction.
I have only notice it when shooting landscape images, but haven't done a thorough test
to see where it goes soft.
I need to find a scene with a range of object distances "around" the scene,
It appears to be OK on the top & bottom. Just an issue, on the L/R sides.
I will also do a focus stacking experiment to see if its distance related
Will post an image later on tonite.
Fred, thanks for reply.
Not likely to return as I bought used and the orig owner bought it 8/2010.
I should have had a better plan for testing out such an ultra-wide.
I don't know of Samyang has any U.S repair either.
If I can get it to clean up at f8 I guess I would consider myself lucky
Yea, I would fear that as this lens is 16 months old.
I think the prior owner used in in such a way he didn't notice.
He shot at f8 or f11 for one.
A lot of interior/architecture stuff.
AND after applying the profile, did cropping.
So he may never had "seen" the smeared focus.
My mistake was not testing it thoroughly. I should have
thought through what kinds of scenes I should do test shots on,
what f-stops. Near far point of focus, etc.
Not much I can do at this point.
I couldn't sell it w/o disclosure & that would mean dirt cheap.
Which is possible.
My only hope is
Somehow get it service/replaced by a generous supplier.
or hope that at f8 & f11 it cleans up.
dswiger -- The Samyang family of lens brands are distributed (and imported) and serviced by Elite Brands.
I sent my 14mm in under warranty repair and received a replacement lens.
Your lens is out of warranty, so you may as well have them work on it instead of going to your neighborhood jeweler!
From my experience, I can say they were honest and gave good service, if a little slow. I recommend them based on my repair and a couple phone calls talking to Morris. I recommend calling first.
Elite Brands
Attn: Morris Didia (Lens Repair)
499 7th Ave, Floor 17 North
NYC, NY 10018
Currently a little bit of a setback.
The folks at Elite Brands don't seem interest in non-warranty work if I can't show where I purchased it. Morris is out so I am dealing with his "staff" I guess.
The lady did have me email her with the full story and she would forward it to Morris.
I am will to pay to get it fixed, up to a point. Anything more than about 50-60% of the lens retail value would not be a wise expenditure.
I have also located a local camera/lens repair store and am awaiting their respons.
I have tried it at f8, f11 & f16. It does clean up a little.
So my options are:
1. Get Elite Brands to fix it for a reasonable fee.
2. Get local repair to fix it for a reasonable fee.
3. Use it at f8 or f11 and crop to 17-20mm equiv and consider myself lucky.
Actually this may not be so bad as it is sharp in that region & most of my
landscape images are at 24-35 and a few at 17-20 (from 17-40 days)
4. Sell it as-is w/full disclosure cheap.
Dan -- One way or another, I do hope it works out for you.
This is an amazing lens, and you really deserve to have a decent copy to use -- you'll be shocked at the difference. Other than severe light falloff at large apertures, it should be good from wide open.
I agree, if you are to pay more than that, you might as well get a new one.
Let's hope Morris will be helpful and get it fixed at modest cost. Or your local place works out.
Fred Miranda wrote:
Once you get a good copy, you will be happy. I would try returning it to the store if you have that option. The elements do not seem to be centered.
Here is a quick test at f/5.6 at a closer range. (This is a full size sharpened in LR with default values)
It is possible that hole lens is tilted, as I stated before.
A single lens element decentring is possible to, but I would think this is much more unlikely.
