Irix 15mm f/2,4 for full frame K-mount

repaap · 09-12-2016, 04:13 AM

Originally posted by clackers

Isn't this a manual focus lens?

I suppose that original meaning of that comment was about most of shots that has been focused too close...I do agree, especially when you are shooting f4 or f2.5.

D1N0 · 09-12-2016, 04:31 AM

Originally posted by wkraus

With all respect for Lenstip, some of these samples appear quite a bit front-focused to me.

The 5d Mk III has only 22mp an anti-aliassing filter and no sharpening applied here.

Sharpened it:

krsto · 09-12-2016, 12:48 PM

The Samyang 135 (considered very sharp) samples made with the same camera, settings, on the same website, so good *for comparison*: Samyang 135 mm f/2.0 ED UMC review - Sample shots - LensTip.com

Na Horuk · 09-13-2016, 11:34 AM

That is weird. It looks like my 16MP K-01 is sharper than that 22MP Canon, because unsharpened raws often look sharper than those jpegs..
So I am willing to accept that the Canon is just so soft and the PP was so so low that it makes even sharp lenses seem soft.

awscreo · 09-13-2016, 05:50 PM

Samyang 14 2.4 lens announced, part of new line up of premium lenses. I wonder if price would be comparable to these irix ones, and would live to see the performance on K-1. If it's as good as they say (and actually has a k mount version), might end up with samyang.

**disasterfilm** · 09-13-2016, 07:39 PM

Originally posted by Na Horuk

That is weird. It looks like my 16MP K-01 is sharper than that 22MP Canon, because unsharpened raws often look sharper than those jpegs..
So I am willing to accept that the Canon is just so soft and the PP was so so low that it makes even sharp lenses seem soft.

It might also have to do with deterioration near the edges of the image circle. Your K-01 has a big advantage that the edges of its frame are still relatively close to the center of the image circle, where as a 5D3's full frame sensor edge is further away from the center. UWA's can see massive loss in IQ and distortion at the edges.

copland35 · 09-14-2016, 02:29 AM

You have to be a good deal more careful in this type of discussion. There is a different set of strategies around image production in the cameras. You must consider both the sensor and the image processing engines. Canon is full frame and 22 mega-pixel. Pentax is APS-C 16 mega-pixel.
Let's choose a lens that can be used on both cameras; the resolution of that lens on both sensors is the same. The sensitivity of each sensor one of its fixed constants. So as long as we supply light within range of the sensors' capabilities we can call this another fixed constant. We can assume the image circle to be significantly larger than any standard sensor if the lens is worth its reputation, so let's call this a fixed constant.

Consequently, the closer spacing of pixels and smaller sized pixels on the APS-C sensor will use more of the resolution potential of the lens. The processing engines equalise and massage the signal from the sensor and deliver it as the finished image. The APS-C needed technical advances to work well and evolved faster than full frame sensors. The developments made in the APS-C sensors are now being applied to full frame sensors and cameras creating the next generation of super full frame cameras. The low light image quality and super-high iso specifications of sensors are actually down to better corrective algorithms in the processing engines.

The story here then is down to how much more advanced the K-01 and its pairing of a higher resolution sensor with a clever processing engine is, compared with the pairing of the sensor and processing engine in the Canon. The cameras have different emphases in their uses that are served by the compromises made in their processors and processing engines. The K-01 therefore can easily be sharper than the Canon, all things being equal.

Na Horuk · 09-14-2016, 03:42 AM

Originally posted by disasterfilm

It might also have to do with deterioration near the edges of the image circle. Your K-01 has a big advantage that the edges of its frame are still relatively close to the center of the image circle, where as a 5D3's full frame sensor edge is further away from the center. UWA's can see massive loss in IQ and distortion at the edges.

True, FF vs. APSC edges is a big big difference. But I was talking even about image centre, where things should be more equal. But true, these two cameras have different bit depth, different AA filters, different pixel density, so comparing them is not always easy. But feel free to click my gallery (sig) to see what my K-01 does with a lowly, slightly decentered copy of Samyang 14mm f2.8 (after some PP, of course, so while direct comparison is not possible, it still has something to say)

Originally posted by awscreo

If it's as good as they say (and actually has a k mount version), might end up with samyang.

The Samyang primes so far had KA mount, so you can use Av or M or P or any mode. If Irix does not have this, this alone is a big advantage

And to be fair, I really wanted to love Irix. It just hasn't lived up to its hype according to what I have seen so far. And I keep my mind open

repaap · 09-14-2016, 05:01 AM - **1 Like**

I'v said it before, and will say it again. Samyang 2.8/14 has poor corners on FF if not stopped down atleast to f8. At f2.8-4 it's edges are unusable. For real, because of vingetting, distortion, color(because of vingetting). Yes, you can PP to work around this things, and have a great shot. But IF I could choose less distortion and better corner performance near f2.8-4 I'd choose that instead. BUT is that worth 300€ differense in prize? When I actually do own SY14 already...that reminds to be seen. 14 mm is WIDE on FF, if I'd correct distortion little a bit in 'wrong way' I'd get nice fishy efect. Even 20 mm is really wide on FF.

---------- Post added 09-14-16 at 15:03 ----------

Originally posted by Na Horuk

True, FF vs. APSC edges is a big big difference. But I was talking even about image centre, where things should be more equal. But true, these two cameras have different bit depth, different AA filters, different pixel density, so comparing them is not always easy. But feel free to click my gallery (sig) to see what my K-01 does with a lowly, slightly decentered copy of Samyang 14mm f2.8 (after some PP, of course, so while direct comparison is not possible, it still has something to say)

The Samyang primes so far had KA mount, so you can use Av or M or P or any mode. If Irix does not have this, this alone is a big advantage

And to be fair, I really wanted to love Irix. It just hasn't lived up to its hype according to what I have seen so far. And I keep my mind open

Irix has KA mount. Only thing 'missing' is AF.

**WPRESTO** · 09-14-2016, 03:17 PM

Here's a site where I found a recent hands-on review of the Irix 15mm, comparing to a Nikon of similar FL. Apologies if someone has already posted a link to this review, BTW: The Irix 15mm appears to be as good or better than any current lens of similar FL.

IRIX 15mm f2.4 - review | Fotoinfo

virusn3t · 09-14-2016, 03:27 PM

Originally posted by WPRESTO

Here's a site where I found a recent hands-on review of the Irix 15mm, comparing to a Nikon of similar FL. Apologies is someone has already posted a link to this review, BTW: The Irix 15mm appears to be as good or better than any current lens of similar FL.

IRIX 15mm f2.4 - review | Fotoinfo

Seems very good lens, if Samyang dont deliver with their 20mm, my next lens will be the irix. I hope Amazon get the distribuition and i could get one.

**WPRESTO** · 09-14-2016, 03:30 PM

Originally posted by virusn3t

Seems very good lens, if Samyang dont deliver with their 20mm, my next lens will be the irix. I hope Amazon get the distribuition and i could get one.

BIG difference in FOV from 20 to 15mm. For me it's not 15 vs 20, it's only one or both.

**Tas** · 09-14-2016, 03:32 PM

Originally posted by WPRESTO

Here's a site where I found a recent hands-on review of the Irix 15mm, comparing to a Nikon of similar FL. Apologies is someone has already posted a link to this review, BTW: The Irix 15mm appears to be as good or better than any current lens of similar FL.

IRIX 15mm f2.4 - review | Fotoinfo

Ta for posting that.

The review is not overly long but the distortion comparison with the 14-24 is what jumped out at me. I no longer need one of these but you have piqued my interest for this new lens and the upcoming reviews on higher res cameras.

Tas

virusn3t · 09-14-2016, 03:33 PM

Originally posted by WPRESTO

BIG difference in FOV from 20 to 15mm. For me it's not 15 vs 20, it's only one or both.

I want/need a wide angle, and 15 or 20 is a good number beign the 15mm in the very extreme on what i feel comfortable, if the 20mm dont give a step up in QC and end up like the 14mm with all the problems of lemons and bad infinity focus, then i will go with the 15mm.

repaap · 09-14-2016, 11:20 PM

Originally posted by WPRESTO

Here's a site where I found a recent hands-on review of the Irix 15mm, comparing to a Nikon of similar FL. Apologies is someone has already posted a link to this review, BTW: The Irix 15mm appears to be as good or better than any current lens of similar FL.

IRIX 15mm f2.4 - review | Fotoinfo

Now, these examples are nice! I really liked realife distortion and lack of it. I must say that My Samyang is feeling little nervous..

09-12-2016, 04:31 AM	#272
D1N0 Pentaxian Join Date: May 2012 Location: --- Photos: Gallery Posts: 6,802	Originally posted by wkraus With all respect for Lenstip, some of these samples appear quite a bit front-focused to me. The 5d Mk III has only 22mp an anti-aliassing filter and no sharpening applied here. Sharpened it: Last edited by D1N0; 09-12-2016 at 04:38 AM.

09-14-2016, 03:42 AM	#278
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Originally posted by disasterfilm It might also have to do with deterioration near the edges of the image circle. Your K-01 has a big advantage that the edges of its frame are still relatively close to the center of the image circle, where as a 5D3's full frame sensor edge is further away from the center. UWA's can see massive loss in IQ and distortion at the edges. True, FF vs. APSC edges is a big big difference. But I was talking even about image centre, where things should be more equal. But true, these two cameras have different bit depth, different AA filters, different pixel density, so comparing them is not always easy. But feel free to click my gallery (sig) to see what my K-01 does with a lowly, slightly decentered copy of Samyang 14mm f2.8 (after some PP, of course, so while direct comparison is not possible, it still has something to say) Originally posted by awscreo If it's as good as they say (and actually has a k mount version), might end up with samyang. The Samyang primes so far had KA mount, so you can use Av or M or P or any mode. If Irix does not have this, this alone is a big advantage And to be fair, I really wanted to love Irix. It just hasn't lived up to its hype according to what I have seen so far. And I keep my mind open Last edited by Na Horuk; 09-14-2016 at 03:58 AM.

09-14-2016, 03:17 PM	#280
WPRESTO Loyal Site Supporter Join Date: Aug 2010 Location: Massachusetts Photos: Gallery \| Albums Posts: 59,111	Here's a site where I found a recent hands-on review of the Irix 15mm, comparing to a Nikon of similar FL. Apologies if someone has already posted a link to this review, BTW: The Irix 15mm appears to be as good or better than any current lens of similar FL. IRIX 15mm f2.4 - review \| Fotoinfo Last edited by WPRESTO; 09-15-2016 at 03:59 AM.

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09-12-2016, 04:13 AM	#271
repaap Pentaxian Join Date: Oct 2010 Photos: Gallery \| Albums Posts: 6,242	Originally posted by clackers Isn't this a manual focus lens? I suppose that original meaning of that comment was about most of shots that has been focused too close...I do agree, especially when you are shooting f4 or f2.5.

09-12-2016, 12:48 PM	#273
krsto New Member Join Date: Mar 2014 Posts: 15	The Samyang 135 (considered very sharp) samples made with the same camera, settings, on the same website, so good for comparison: Samyang 135 mm f/2.0 ED UMC review - Sample shots - LensTip.com

09-13-2016, 11:34 AM	#274
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	That is weird. It looks like my 16MP K-01 is sharper than that 22MP Canon, because unsharpened raws often look sharper than those jpegs.. So I am willing to accept that the Canon is just so soft and the PP was so so low that it makes even sharp lenses seem soft.

09-13-2016, 05:50 PM	#275
awscreo Veteran Member Join Date: May 2016 Photos: Gallery \| Albums Posts: 2,722	Samyang 14 2.4 lens announced, part of new line up of premium lenses. I wonder if price would be comparable to these irix ones, and would live to see the performance on K-1. If it's as good as they say (and actually has a k mount version), might end up with samyang.

09-13-2016, 07:39 PM	#276
disasterfilm Site Supporter Join Date: Aug 2014 Location: Texas Posts: 406	Originally posted by Na Horuk That is weird. It looks like my 16MP K-01 is sharper than that 22MP Canon, because unsharpened raws often look sharper than those jpegs.. So I am willing to accept that the Canon is just so soft and the PP was so so low that it makes even sharp lenses seem soft. It might also have to do with deterioration near the edges of the image circle. Your K-01 has a big advantage that the edges of its frame are still relatively close to the center of the image circle, where as a 5D3's full frame sensor edge is further away from the center. UWA's can see massive loss in IQ and distortion at the edges.

09-14-2016, 02:29 AM	#277
copland35 New Member Join Date: Feb 2016 Posts: 10	You have to be a good deal more careful in this type of discussion. There is a different set of strategies around image production in the cameras. You must consider both the sensor and the image processing engines. Canon is full frame and 22 mega-pixel. Pentax is APS-C 16 mega-pixel. Let's choose a lens that can be used on both cameras; the resolution of that lens on both sensors is the same. The sensitivity of each sensor one of its fixed constants. So as long as we supply light within range of the sensors' capabilities we can call this another fixed constant. We can assume the image circle to be significantly larger than any standard sensor if the lens is worth its reputation, so let's call this a fixed constant. Consequently, the closer spacing of pixels and smaller sized pixels on the APS-C sensor will use more of the resolution potential of the lens. The processing engines equalise and massage the signal from the sensor and deliver it as the finished image. The APS-C needed technical advances to work well and evolved faster than full frame sensors. The developments made in the APS-C sensors are now being applied to full frame sensors and cameras creating the next generation of super full frame cameras. The low light image quality and super-high iso specifications of sensors are actually down to better corrective algorithms in the processing engines. The story here then is down to how much more advanced the K-01 and its pairing of a higher resolution sensor with a clever processing engine is, compared with the pairing of the sensor and processing engine in the Canon. The cameras have different emphases in their uses that are served by the compromises made in their processors and processing engines. The K-01 therefore can easily be sharper than the Canon, all things being equal.

09-14-2016, 05:01 AM - 1 Like	#279
repaap Pentaxian Join Date: Oct 2010 Photos: Gallery \| Albums Posts: 6,242	I'v said it before, and will say it again. Samyang 2.8/14 has poor corners on FF if not stopped down atleast to f8. At f2.8-4 it's edges are unusable. For real, because of vingetting, distortion, color(because of vingetting). Yes, you can PP to work around this things, and have a great shot. But IF I could choose less distortion and better corner performance near f2.8-4 I'd choose that instead. BUT is that worth 300€ differense in prize? When I actually do own SY14 already...that reminds to be seen. 14 mm is WIDE on FF, if I'd correct distortion little a bit in 'wrong way' I'd get nice fishy efect. Even 20 mm is really wide on FF. ---------- Post added 09-14-16 at 15:03 ---------- Originally posted by Na Horuk True, FF vs. APSC edges is a big big difference. But I was talking even about image centre, where things should be more equal. But true, these two cameras have different bit depth, different AA filters, different pixel density, so comparing them is not always easy. But feel free to click my gallery (sig) to see what my K-01 does with a lowly, slightly decentered copy of Samyang 14mm f2.8 (after some PP, of course, so while direct comparison is not possible, it still has something to say) The Samyang primes so far had KA mount, so you can use Av or M or P or any mode. If Irix does not have this, this alone is a big advantage And to be fair, I really wanted to love Irix. It just hasn't lived up to its hype according to what I have seen so far. And I keep my mind open Irix has KA mount. Only thing 'missing' is AF.

09-14-2016, 03:27 PM	#281
virusn3t Veteran Member Join Date: Jul 2014 Posts: 676	Originally posted by WPRESTO Here's a site where I found a recent hands-on review of the Irix 15mm, comparing to a Nikon of similar FL. Apologies is someone has already posted a link to this review, BTW: The Irix 15mm appears to be as good or better than any current lens of similar FL. IRIX 15mm f2.4 - review \| Fotoinfo Seems very good lens, if Samyang dont deliver with their 20mm, my next lens will be the irix. I hope Amazon get the distribuition and i could get one.

09-14-2016, 03:30 PM	#282
WPRESTO Loyal Site Supporter Join Date: Aug 2010 Location: Massachusetts Photos: Gallery \| Albums Posts: 59,111	Originally posted by virusn3t Seems very good lens, if Samyang dont deliver with their 20mm, my next lens will be the irix. I hope Amazon get the distribuition and i could get one. BIG difference in FOV from 20 to 15mm. For me it's not 15 vs 20, it's only one or both.

09-14-2016, 03:32 PM	#283
Tas Site Supporter Join Date: Aug 2013 Location: Brisbane, QLD Photos: Gallery \| Albums Posts: 2,202	Originally posted by WPRESTO Here's a site where I found a recent hands-on review of the Irix 15mm, comparing to a Nikon of similar FL. Apologies is someone has already posted a link to this review, BTW: The Irix 15mm appears to be as good or better than any current lens of similar FL. IRIX 15mm f2.4 - review \| Fotoinfo Ta for posting that. The review is not overly long but the distortion comparison with the 14-24 is what jumped out at me. I no longer need one of these but you have piqued my interest for this new lens and the upcoming reviews on higher res cameras. Tas

09-14-2016, 03:33 PM	#284
virusn3t Veteran Member Join Date: Jul 2014 Posts: 676	Originally posted by WPRESTO BIG difference in FOV from 20 to 15mm. For me it's not 15 vs 20, it's only one or both. I want/need a wide angle, and 15 or 20 is a good number beign the 15mm in the very extreme on what i feel comfortable, if the 20mm dont give a step up in QC and end up like the 14mm with all the problems of lemons and bad infinity focus, then i will go with the 15mm.

09-14-2016, 11:20 PM	#285
repaap Pentaxian Join Date: Oct 2010 Photos: Gallery \| Albums Posts: 6,242	Originally posted by WPRESTO Here's a site where I found a recent hands-on review of the Irix 15mm, comparing to a Nikon of similar FL. Apologies is someone has already posted a link to this review, BTW: The Irix 15mm appears to be as good or better than any current lens of similar FL. IRIX 15mm f2.4 - review \| Fotoinfo Now, these examples are nice! I really liked realife distortion and lack of it. I must say that My Samyang is feeling little nervous..