• 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Forums > Back > Some details on Irix 11/4
#1
As the weather is not very inviting to go out and take better shots than yesterday after I bought that lens, I thought I could share some details which were new, at least for me. Not much test reports available at the moment as well. But both Irix-lenses (or all 4, as the two focal lengths are available each in two versions, firefly (less expensive) and blackstone (more metal on it).

 

General details

 

But the following is not about the optical quality. That could be much worse, but at a price point of 900.- for an ultra-wide (not to use the term "hyper wide" for FF sensors obviously the quality has some space to improve. More on that later.

 

After pulling the lens out of its soft shell case, which sits in a tin-box which sits in a card-box (you get a lot of unboxing-show for that money... ^_^ ) I discovered a second rear-cap. Maybe necessary? Mots of that cap is of comical shape, so it could slip out the fingers. Put that off and see a metal mount with rubber gasket (the blackstone version has better weather sealing than the firefly-version, I think) and the filter holder for 30×30 gelatine filters. And the electrical contacts. Aperture is set by camera (but mechanically, like the non-E Nikkors), the lens delivers EXIF like focal length and aperture value - well made, Irix! Not just a manual lens like Laowa.

 

The dealer had the gelatine filters. A little plastic bag, containing 5× ND4, 5× ND8, 5× ND16, cost me 18.- francs extra, more on them also a bit later. 

 

Focus-ring is well damped, has a DoF scale and also a hyperlocal scale - both I don't trust with a + 40 MP camera. These scales are, opposite of what Irix claims, not phosphorescent. They don't save light to glow in the dark, but you can see them much better than most AF scales.

 

The ∞-position clicks in, you can feel it. If one decides to go hyperfocal, you can lock that position. And the lock is solid, although I would recommend to hold the lens on it's fixed diameter if you want to unmount it to put in a gelatine filter and remount it again.

 

Now we're coming to the frontside. After removing the most clever designed lens cap I have seen on ultra-wide angles, the bulbous front element is exposed. And protected by a plastic lens hood which I cannot remove. That hood shows a little screw which holds a cover. After removal I could adjust ∞-position, or better said the click-position of it. There's an extended manual available for this operation. The manual itself is well done and comes on 11 languages.

 

Back to the clever cap. Two buttons at it's side release two plastic hooks which hold it in place. How often I pulled an ultra wide lens out of the bag and the front cover was already off because it stuck in the bag - no longer with this design  Smile .

 

Gelatine filters, some thoughts about

 
15 little filters for just 18 francs - or a filter holder and three filters (Lee, NiSi, Hittech, Haida, WonderPana and what else) which will set you back between 300-600$ - where's the caveat?
 
They are fiddlicult to use, I'd say. 5 gelatine filters, in a little plastic bag, in another plastic back to contain the 3 sets - ever tried to get the dust off a negative film with an antistatic cloth? The filters collect dust like magnets collecting nails. A little bit of wind and off they go. Would I feel happy to remove the lens to change the ND value, on a beach, in the rain, in the fog or water spray on a waterfall? What good is the weather sealing for if I have to remove the lens to change a filter?
 
But then, rain is also no friend of the super expensive filters, as well as sand and wind and sea salt. And compared to Hittech, the Irix ND filters are neutral. And not giving a weird magenta cast.
 
The quality 
 
Although the lens is rectilinear and no fisheye, I need all the bells and whistles in Capture One to bring the results from "wellll, I'd say..." to "acceptable". Wanna have a look? See for yourself.
 
Chromatic aberration is active, additionally removing purple seams - but that's not enough. Reducing the seams still leave purple parts in the dark details, like twigs. So, another go with the color editor to reduce saturation was necesary. Sharpness and falloff compensation are between 20 and 50, Distortion slider is usually around 40-50 (max. values are 120 for non-CaptureOne users).
 
But the real problem is the perspective distortion. A picture from Sigma 14/1.8 or Nikkor 14-24/2.8 @ 14 mm will always look more natural, more real and less of a caricature. Later I will set up a little gallery.
 
There's another issue. All pictures looked good at the LCD of D850, and sh*t on the Mac. I set Capture One to a preview size of 2560 pixel at longest side. So it has to downscale them if I'm not looking at a picture in fullscreen mode. This downsizing softens all details. Which can be seen in a full-size export viewed at 100% but still with some softness. I didn't know if it's the lens or the JPG compression. So I checked. A 12 MB JPG against a 260 MB TIF.
 
It was no JPG problem. I just don't have any high hopes for astrophotography.
  Reply
#2
Looks somewhat softer on the left.

  Reply
#3
Corners are quite soft. Actually, only the center seems somewhat sharp.

And I thought my Fuji 18mm f2 was soft in the corners.

--Florent

Flickr gallery
  Reply
#4
Yeah, Irix does a lot of things to get the picture rectilinear. Other than that, sharpness is suffering due to CA and purple fringing. I just think, at this price range (the firefly version is around 500 $ and Irix states it has the same optics as the blackstone version) I better don't expect too much.

 

I didn't write the post to point out the optical qualities. I was just surprised that Irix took care of a lot of little details, like the lockable Front cover.

  Reply
#5
I'm wondering - what do you need 11mm for? Just a question. Because I'm a bit lost at such focal lengths.

  Reply
#6
Looks softer on the left? I looked at an image with somewhat comparable subject distance left/right, and don't really see that https://sojujo.smugmug.com/Testshots/Iri...-krMvjPm/O

  Reply
#7
Quote:Corners are quite soft. Actually, only the center seems somewhat sharp.

And I thought my Fuji 18mm f2 was soft in the corners.
The corners mainly are "pulled apart" by astigmatism/coma (can't yet really tell what is what) and CA. Once you correct the CA they are not that soft.

Your Fuji is a 28mm f3 FF equivalent.... 
  Reply
#8
Quote:The corners mainly are "pulled apart" by astigmatism/coma (can't yet really tell what is what) and CA. Once you correct the CA they are not that soft.

Your Fuji is a 28mm f3 FF equivalent.... 
 

Not sure why you always have to bring equivalency into everything.

You're missing the point.

The point is that my Fuji 18mm's corners are not that bad compared to the samples shown here.

Nothing more, nothing else.
--Florent

Flickr gallery
  Reply
#9
Quote:Not sure why you always have to bring equivalency into everything.

You're missing the point.

The point is that my Fuji 18mm's corners are not that bad compared to the samples shown here.

Nothing more, nothing else.
You don't take into account correcting the CA. With your not very wide angle lens, I am sure you do have CA correction. And you compare corners from 11mm (which always will look pulled apart in some way or another) to a mere 28mm equivalent. Which is the odd thing.

 

Also... To what are you comparing 45.7 megapixel images, exactly?
  Reply
#10
Quote:I'm wondering - what do you need 11mm for? Just a question. Because I'm a bit lost at such focal lengths.
 

The answer is sort of "why do you want to climb this mountain?" "because it's there". Honestly, it was just curiosity about the brand and to have a wide angle I nearly could use as rear mirror  Big Grin

 

As a little bit more satisfying answer: I sometimes need to document machinery parts and I never have enough space or get enough angle. The lens has massive "reality" distortions, but it's also fun to use and enough to get an overview. Also (but that I haven't known before I decided to purchase it) it's challenging my Capture One skills. All of you detected corner softness, but if I posted the RAWs...  :wacko: .

 

I would also get a oretty wide angle if I stitch tow 14 mm shots together. I'm just afraid that due to geometrical distortions, the stitcher would have a hard time. But I admit, I never tried...

  Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)