Irix Issues - Bad Luck or User Error

[@samimqazi4270]

IRIX Lenses are beast but they do got Aperture problem and i dont know how to fix mine "IRIX 15mm Lens"

[@CapeNightPhotography]

I don't know if it is fixable unfortunately.

[@johnchen1469]

I wish you solved your Irix 11mm problem 1:49 already. I have K1m1 and this lens, and I have exavtly the same issue.

[@dopetom]

I have this same combination, k1m1 and irix 11mm. I can honestly say I do not have this issue.. but I will scrutinise it a bit further. I have found the lens to be so different from the others I use (generally primes 50+) that I’ve not used it as much.. but generally, it seems to have been consistent.. out of interest are you using the black stone or the firefly, (not that I think it’s a quality matter, I use the firefly) I think the previous commenter had the best input, if you can open a line of comms with irix, that would be ideal, because they seem like a company that are trying to engineer new tools for the market.. by the way, your video on the k1 astrotracer mode was very helpful, thank you for your concise and helpful content✌️

[@CapeNightPhotography]

Hey, thanks for your feedback! I would definitely use this lens for all my real estate shoots because (when it works) it is perfect for interiors and the tight spaces I frequently have to deal with. I haven't seen anyone else have this issue either so I just don't know where to go with it at this point. I think I may sell it to put toward another lens from a different manufacturer. The IRIX rep was very friendly and responsive and I certainly had no issues with her. Glad you liked the astrotracer video!

[@dopetom]

That is a shame, like you said it is a quirky lens re the scope and perspective it produces.. ​if there is anything I can do to help let me know.. but yea is quite the strange bug,, especially the aperture winking.. do you always use the electable dial set to ff/crop? I’m sorry you’ve not had more luck with it.. happy to video chat if that help@@CapeNightPhotography

[@GuidoMengelberg]

At first try I couldn't reproduce your results. C26 is set 2 - and there are 5+1 contacts between lens and K-1. I'm going to test it more intensively at the weekend.

[@CapeNightPhotography]

Would love to hear the results. I have changed any potentially applicable menu options to see if the issue was buried in a setting.

[@ioio5993]

I've been on the fence on acquiring the new IRIX 21/f1.4 ever since I heard about the lens. My interest stems from the 1.4 aperture for shooting the Milky Way. I'll probably go ahead and get the lens. Have you posted about this over on the Pentax Forums? There are a number of lens guys over there that may help. Back to your specific problems. Several third-party manufacturers have had problems in the past (Sigma comes to mind here). The OEMs really do not provide any design guidance in terms of the lens interfaces (mechanical, electrical, logical), so the interfaces tend to be reverse engineered. That means that there can be some differences in terms of how the lens interface works as designed (by Pentax) and implemented by the third-party manufacturer. Since this is a manual lens and not AF - I would think that the interface would be much simpler (lens ID and aperture information) - but who knows. Another area that may explain some of this is the chips used in the lens. All of your copies may have been from the same manufacturing batch - and thus have chips from the same batch from the semiconductor manufacturer's FAB, which differs ever so slightly from the batch of chips that were used in IRIX's initial development. I would suspect that there is probably an analog component there in the design. Analog design is somewhat of a lost black engineering art these days. I really think that the only approach is to work with IRIX on this. Since you have two bodies that exhibit the same problem, lending IRIX one for a month so that they can characterize the problem would be my main suggestion. [I'm a retired embedded real-time software systems engineer for 50 years and these random types of problems are difficult. Being able to repeat them is the key to solving the problem.]

[@CapeNightPhotography]

I appreciate the time you took to write this detailed response. I certainly would be open to doing what you suggest if they felt like it would be helpful to them. I hear what you are saying about the batch. I haven't posted on the Pentax Forums but I am hoping this makes it to some of those folks. I am trying to weigh the amount of effort I want to continue to put into this situation after already having lost so much time trying to get a workable copy for my K1 bodies. That said, winter is coming and I will have more time to focus (pun intended) on such things :)

[@samimqazi4270]

i have the same issue ... over or sometimes under exposed ... i haven't update it ,,,donno if that gonna help / i use it with my Canon 6D and also Lumix 5S and it shows issues with both cams

[@CapeNightPhotography]

No kidding? That's interesting to hear and I appreciate you letting me know. I have since listed mine for sale because I just can't get it to constantly work with my Pentax bodies. In reading the reviews, I seem to be in the minority. But two copies not working with two Pentax bodies is too much of a coincidence to me.

[@glebrasseur]

I got the problem for years ! I thought mine was Brocken. It gives me a bit of hope to find a solution if if is a design problem. Btw, I got the 15mm and never had any problem with it, really great lense.

[@CapeNightPhotography]

Well, that makes me feel better that I am not the only one! I have heard great things about the 15. My 15-30 hits that range for me and I am pleased enough with it to not need another 15 right now...but I am glad yours is working!

[@RB-yx6bc]

At first I thought you might have exposure bracketing on, and forgot. I did that and felt like I was chasing my tail with exposure. But that doesn’t seem to be the case with you.

[@CapeNightPhotography]

That's exactly what it looks like, doesn't it? This was also one of the first things I checked because it seemed so similar.

[@ashwanibhola3766]

Did you happen to reach out to Irix about this issue to find out if they were aware of it? And whether they have any firmware updates that were available or being worked on that might help?

[@CapeNightPhotography]

Up until this point, I have only framed my communication with them as a replacement request. Part of the reason I made this video was with the intent of being able to send it to them and say "here is my problem." This is the next step I think.