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12-08-2016, 03:58 PM   #61
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QuoteOriginally posted by laci Quote
I have just finished test. I have really same issue :-(. How did you proceed with RMA?

Best regards,
Laci
Hi laci, I'm sorry to hear that you have the same problem... I use a k5iis, but in your k1 the problem is way more visible.

I have just called to the store telling my problem and saying that i would like my lens to be replaced by another one. So I think you should contac with your store and tell about the problem, this problem should be known by Irix...

These days, here in Spain are like national holidays, so I haven't received any answer, when I recieve an answer I will tell you guys what happens.

Best regards

12-08-2016, 06:55 PM   #62
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Just out of curiosity, does anyone of you have any experience with the Samyang etc. 14 2.8? I've read a lot about decentering and some kind of WA distortion. This post on dpreview by BobORama has some interesting points.

"I like the K-1 with the Samyang 14 as well. It is a ridiculously sharp lens for the price, and having used it with pixel shift produces a significant increase in sharpness - again, reinforcing the lens is, itself, out performing the sensor.
This lens does over-correct spherical aberration which seems to be their way of reducing coma. This results in zoning - that is, multiple focal points, or a continuum of focal points. So best focus for the center will never be best focus for the center. The center sharpens up first, then the corners.
Its sort of like no-line bifocals - you have two focal distances with a continuum between them. So this is why you hear people debating where infinity is on this lens.
With such a short focal length, even with the optical zoning ( multiple actual focal lengths ), you can set the focuser so that all of the optical zones are in hyperfocus. Now you do favor the center OR the edges, but both will be very sharp. For astro work, you place it about dead center and the entire frame will be very good."
12-08-2016, 09:00 PM   #63
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I just got sy 14 2.8, I love it so far. Looks sharp across the frame, in-camera aperture control, distortion can be fixed with a simple profile in LR, and it was very affordable (249$ on black Friday sale on Amazon). I was considering irix few weeks ago, but honestly I think samyang is good enough for what I need and saved me few hundred bucks.

Edit: while I don't have much experience with this lens yet, I haven't noticed the effect guy from dpreview mentioned. At 2.8 corners are not pin sharp, sure. But at f8-11 and onwards the whole image is sharp, and that's where I'd use it for landscape work. I've yet tested astro with it, but people say good things about it in that regard
12-10-2016, 09:40 AM   #64
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QuoteOriginally posted by laci Quote
I have just finished test. I have really same issue :-(. How did you proceed with RMA?

Best regards,
Laci
Hi, Sorry to hear you may have a bad copy, but are you sure that your target is really perpendicular (90 degrees) ? Because the image suggest they are not since we see the borders with angles...

12-10-2016, 03:53 PM   #65
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Hi Weevil, yes i am sure. I also did another test to be sure. It this test i did focus via live view on left side of the picture and take a photo. Then i did same with right side of the picture. If i compare both photos, much sharper photo is on second picture (right side of the frame).
12-14-2016, 12:04 AM - 2 Likes   #66
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A few more pix .....





12-14-2016, 09:36 AM   #67
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QuoteOriginally posted by awscreo Quote
I just got sy 14 2.8, I love it so far. Looks sharp across the frame, in-camera aperture control, distortion can be fixed with a simple profile in LR, and it was very affordable (249$ on black Friday sale on Amazon). I was considering irix few weeks ago, but honestly I think samyang is good enough for what I need and saved me few hundred bucks.

Edit: while I don't have much experience with this lens yet, I haven't noticed the effect guy from dpreview mentioned. At 2.8 corners are not pin sharp, sure. But at f8-11 and onwards the whole image is sharp, and that's where I'd use it for landscape work. I've yet tested astro with it, but people say good things about it in that regard
I appreciate your feedback!
12-16-2016, 09:06 AM   #68
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For those who can read spanish, this review against the Samyang 14mm f2.8 can be of interest
Comparativa: Irix 15mm vs Samyang 14mm - Foto24

12-17-2016, 08:13 PM - 7 Likes   #69
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I had a chance to try out my IRIX on a night sky recently using the Astrotracer function on my K1. "Seeing" was not ideal due to an onshore sea breeze but I'll be quite happy to continue using the lens for this purpose.

* My copy of the lens seems nicely calibrated at the factory for infinity.
* Stars over the majority of the fov are nice point forms. There seems to be some coma near the right edge but it's pretty minor, and some star trailing is evident away from the centre due to the very wide fov.
* Constellation shapes are distorted towards the edges.
* Colour rendering is quite acceptable to me with stars like Aldebaran and Betelgeuse appearing as they should, although a very slight shift in colour towards the red end may be warranted.
* I found that f2.8 at ISO 800 to 1600 captured plenty of stars with good contrast.

I've included four images below; not the best "seeing" as I've noted earlier, but a happy start with the IRIX. (Notes on Flickr).







12-17-2016, 11:13 PM - 2 Likes   #70
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QuoteOriginally posted by OzzRod Quote
I had a chance to try out my IRIX on a night sky recently using the Astrotracer function on my K1. "Seeing" was not ideal due to an onshore sea breeze but I'll be quite happy to continue using the lens for this purpose.

* My copy of the lens seems nicely calibrated at the factory for infinity.
* Stars over the majority of the fov are nice point forms. There seems to be some coma near the right edge but it's pretty minor, and some star trailing is evident away from the centre due to the very wide fov.
* Constellation shapes are distorted towards the edges.
* Colour rendering is quite acceptable to me with stars like Aldebaran and Betelgeuse appearing as they should, although a very slight shift in colour towards the red end may be warranted.
* I found that f2.8 at ISO 800 to 1600 captured plenty of stars with good contrast.

I've included four images below; not the best "seeing" as I've noted earlier, but a happy start with the IRIX. (Notes on Flickr).






Wow ! Cool! That the kind of photos I wanted to see with the Irix... I especially like the 3rd one...

I think it has less softness and distortion toward the edges compared to the shots I did this summer with the Bower (Samyang) 14mm/2.8 (below)

La Voie lactée au dessus de Owl's Head/ The Milky Way over Owl's Head
by Sylvain Cote, sur Flickr
12-18-2016, 06:52 PM   #71
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QuoteOriginally posted by OzzRod Quote
a happy start with the IRIX.
QuoteOriginally posted by Weevil Quote
I think it has less softness and distortion
Gentlemen, thanks for the images and comparison! I don't have a faster WA prime yet for stars. Real world examples are of great value.
12-20-2016, 05:50 PM   #72
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Hi all, posted some humble shots from irix 15 with pentax K1. Thank you.



01-02-2017, 04:00 AM   #73
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@jmpince and laci
My 15mm Blackstone arrived a few days ago and I seem to have the same decentering problem. Right side is perfectly sharp through all apertures but the left side is not sharp just like yours. It gets a little better stopping down but the problem is still there.
Have you received answer or even already have a new copy from IRIX? If so did they replace it or repair it? How was the response time and quality of service?
01-03-2017, 02:32 AM - 4 Likes   #74
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One more from the Firefly

Found one gripe with my copy. It's a pain in the neck to get a circular filter screwed on. The filter has no trouble going on a step up ring otherwise. Guess you can't have perfection for 300 Euros.
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01-09-2017, 06:34 PM - 1 Like   #75
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QuoteOriginally posted by mag07 Quote
One more from the Firefly

Found one gripe with my copy. It's a pain in the neck to get a circular filter screwed on. The filter has no trouble going on a step up ring otherwise. Guess you can't have perfection for 300 Euros.
Wow.. nice shot..
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