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09-19-2017, 10:14 AM   #166
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QuoteOriginally posted by Erd§ Quote
That's laughable since they had to use a cheap adapter to test the lens, I wonder if the adapter manufacturer is also renowned for its lens mount reliability?
Also, did you see the images they shot when "testing" the lens? I'll bet they were not so generously provided.
A shame, really - good copies of the lens are...well, the evidence is here within this thread.
Good luck on this, I'm following this thread....the IRIX is on my near-term purchase list.

Thanks/Bill

09-28-2017, 01:25 PM   #167
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QuoteOriginally posted by OzzRod Quote
And here's an uncropped star shot showing part of the Milky Way. A 90 second exposure at f4.5 using the K1's in-built astrotracer function.
QuoteOriginally posted by wgosma Quote
....the IRIX is on my near-term purchase list.
Same for me, almost ready to pull the trigger...
but after reading some external reviews, I see that some mention it has too many COMA and Astigmatism aberrations for night landscapes ...

Anyone here can validate it is the case ?
09-28-2017, 03:18 PM   #168
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QuoteOriginally posted by Weevil Quote
Same for me, almost ready to pull the trigger...
but after reading some external reviews, I see that some mention it has too many COMA and Astigmatism aberrations for night landscapes ...

Anyone here can validate it is the case ?
I think all lens aberrations are very well controlled in this lens from the examples I have seen to date. I think it compares very favorably to other lenses in this range.

Ken Rockwell likes it and he is pretty picky. ;-)
09-28-2017, 08:12 PM   #169
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QuoteOriginally posted by Rickster Quote
I think all lens aberrations are very well controlled in this lens from the examples I have seen to date. I think it compares very favorably to other lenses in this range.

Ken Rockwell likes it and he is pretty picky. ;-)
Thanks for the limk, this is a very interesting site... but he did not covered the COMA effects of a Starfield type of photos...

09-28-2017, 09:19 PM   #170
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QuoteOriginally posted by Weevil Quote
Thanks for the limk, this is a very interesting site... but he did not covered the COMA effects of a Starfield type of photos...
Here's an example star-field with the Firefly. Looks good to me. ;-)

Irix 15mm f/2.4 Firefly by Irix lens - Photo 224561769 / 500px
10-01-2017, 08:24 AM - 4 Likes   #171
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Went over to the Oneida Narrows in Southeast Idaho to capture some fall color. All images K-1 with Irix 15mm













The image below taken on Bartlett Camp Road in Bear Lake
10-01-2017, 01:39 PM   #172
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QuoteOriginally posted by Rickster Quote
Went over to the Oneida Narrows in Southeast Idaho to capture some fall color. All images K-1 with Irix 15mm
The image below taken on Bartlett Camp Road in Bear Lake

That's a fine set.
10-01-2017, 10:31 PM   #173
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QuoteOriginally posted by WPRESTO Quote
That's a fine set.
Thank you for your kind words. This Irix 15mm lens is beginning to grow on me. ;-)

10-05-2017, 01:22 PM - 2 Likes   #174
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Irix 15mm on K1

So I just started with the K1 a couple of weeks ago and just got some lens in other than the 28-105 kit lens. This was with the Firefly 15mm hand held No HDR just simple PP for contrast and a 16x9 crop. Just as an FYI I have been shooting Nikon and Leica for the last 15 years and the K1 has to be one of the best I have used.
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10-05-2017, 04:14 PM   #175
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Nice shot, thanks for sharing! You'll enjoy the K-1, NICE camera - I just got a Firefly 15 mm lens and started playing with it, pretty sweet lens for the price!
Bill
10-05-2017, 07:58 PM   #176
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the decentering question continued (tldr: the lens is probably working as expected)

QuoteOriginally posted by Rickster Quote
I wouldn't send it back just yet.

I'm not sure this technique is the right way to test this issue. (Decentering) I think it is best to do a critical focus on a distant object in the center of the lens field, lock the focus, then rotate & tilt the camera on your tripod (you are using a tripod, right?) to take 4 additional frames of that same object in the 4 corners of the image field. In your test above the towers on the left and right are not in the same image plane as the center focal point.
After doing what you said I concluded that it's not decentered after all. I think that the "decentering" is actually an optical illusion resulting from the fact that distortions don't pick up any extra--I'm not sure what the word is--definition or detail. Looking at a stop sign straight on I can see it clearly and it's small. The same stop sign is stretched when it's at the left edge of the screen, but it's not blurry. Now, the leaves behind the stop sign look much blurrier at the edge, but that's only because they're distorted. In my pic, number 1 is at the centre, 2 just to the left and then further to the left with each (native res) crop until we see the left edge at number 7. I don't think those are blurry, just less and less defined. Do you agree?
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10-06-2017, 10:43 AM - 3 Likes   #177
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Solitude.
Irix 15mm F2.4

10-06-2017, 09:29 PM   #178
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QuoteOriginally posted by PiotrM Quote
After doing what you said I concluded that it's not decentered after all. I think that the "decentering" is actually an optical illusion resulting from the fact that distortions don't pick up any extra--I'm not sure what the word is--definition or detail. Looking at a stop sign straight on I can see it clearly and it's small. The same stop sign is stretched when it's at the left edge of the screen, but it's not blurry. Now, the leaves behind the stop sign look much blurrier at the edge, but that's only because they're distorted. In my pic, number 1 is at the centre, 2 just to the left and then further to the left with each (native res) crop until we see the left edge at number 7. I don't think those are blurry, just less and less defined. Do you agree?
Just a smidgen of chromatic distortion at the edge. I don't see any decentering in these examples.
10-08-2017, 06:49 AM - 4 Likes   #179
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2 image panorama with K-1 and Irix 15mm of Blue Pond Spring, St Charles Canyon, Bear Lake Idaho

10-08-2017, 09:05 AM - 1 Like   #180
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QuoteOriginally posted by Rickster Quote
2 image panorama with K-1 and Irix 15mm of Blue Pond Spring, St Charles Canyon, Bear Lake Idaho
That is a very satisfactory image in every way. Why would anyone spoil the pleasure of seeing it to worry about whether the edges are as sharp as the center?
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