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If you come from a video background (like me) or a film background then you are used to the joy of an iris on a lens that is smooth as butter and that is located where it should be…on the lens.

Every 2/3″ lens I used in my 23 year career has had the ability to change the iris in micro adjustments. Perfect for riding exposure during a shot. My Sony EX1 (now deceased) and my EX3 (alive and clicking but gathering dust) have a proper smooth iris on the lens, and this is especially cool on the EX1 as it is not a removable lens. Many other cameras of that ilk have the iris control on the camera. Smoothish but not the same as having it on the lens.

One of the biggest issues I came across when I first started using 35mm adaptors with still lenses was the inability to change exposure on the lens during a shot due to the iris moving in clicks. This was not so bad on 35mm adaptors, as I always rode the exposure on my EX1 lens which also maintained my depth of field. The 35mm lens on the front stayed at the same aperture to hit the ground glass creating that chosen depth of field.

But, with DSLRs it has gotten worse. Stills guys are used to it. But I was not. All Canon made lenses and the MAJORITY of the third party lenses and many Nikon lenses (although at least you generally get a choice with Nikon made glass) have the iris controlled within the camera. I am sure most stills guys are used to that now and to be honest they don’t need to ride exposure during a shot as that is a purely video thing. The majority of lenses controlled by the Canon cameras from the dial change the iris in 1/3 stop increments. This is nowhere near fine enough to use during a shot. Actually the Canon C300 is the best camera I have used for using Canon EF and EFS glass as it lets you change exposure in “fine” mode which is around 1/8 of a stop give or take…This is “just” about smooth enough to get away with during a shot when you need to change exposure. The superb RED Epic Canon mount for example only lets you change the iris in 1/3 stop increments again (that may change in firmware).

You may ask why would you want to change exposure during a shot? Well as a predominantly documentary filmmaker, a lot of what I shoot is at the mercy of the light as clouds go past etc. For my drama work then if the light changed we cut and do a new take.

There is a, semi solution. Unfortunately it’s not for Canon made glass as you are stuck. It’s a physical thing not having a manual iris ring…I have been trying to tell people not to buy Zeiss ZE glass for their cameras but the Nikon mount ZF instead…why? It has a manual iris on it.

ZF with manual iris

ZE with no manual iris

With an adaptor like the Fotodiox Pro the ZF will go on a Canon body no problem. It will also go on just about any camera out there with an adaptor, and as it has a manual iris you don’t have the issues of waiting for a Canon EF electronic mount adaptor to come out…

The downside it the ZF focuses the “Nikon way” round, which is the opposite to any lens I have ever used. You get used to it though.

There are loads of other lenses with manual iris I have used, other than Nikon glass, like the budget lenses by Samyang/ Rokinon. Even the Canon one has a manual iris! They are pretty good and worth checking out. I have the 35mm F1.4 Samyang and use it lot.

So now we have got to the benefits of having a manual iris, but we still have issues. The iris is not smooth. In fact it’s worse in some cases. Instead of the 1/3 stop increment the Canon cameras have, the ZF lenses only have 1/2 stop increments between the full stops. Even less smooth. I used a Contax lens the other day and it had no increments at all. It went from one stop to the next. Terrible for riding the exposure. That is where people like Eddie Houston, The Lens Doctor,  come in. Eddie is based in Scotland and camera recommended by my friend Dan Chung. For a relatively low cost (dependent on the lens) he will “de-click” your lenses for  you. So suddenly you have cine-lens-like smoothness in the iris ring. He removes the clicks but adds enough resistance so it’s not crazy loose. I recently got him to do all my ZF glass, and it’s like having a whole new set of glass. I also have had my Samyang de-clicked and recently bought the ZF 35mm F1.4 which I am going to send to him shortly. So instead of 1 stop, or 1/2 stop or 1/3 stop it’s micro fine adjustments. Suddenly you can ride the exposure smoothly!

Eddie has also repaired a couple of my lenses and done a wonderful job. I cannot recommend him enough.

If you don’t live in the UK there are loads of places that will offer the same service. Make sure you get a recommendation before you send your glass off but I promise you this, it won’t change your life, but it will make shooting a lot easier with still lenses!

If you have any global recommendation for places like “The Lens Doctor” please share them in comments below.

USA based? Then Matt Duclos is your man. He can add front filter diameters so all your lenses match and permanent focus wheels too…

There is one other way to get smooth iris change, and this will not effect your DOF like changing an IRIS will, and that is a Variable ND. I have been using them since I started with DSLRs and they have been a godsend. No good in lower light conditions as even at their minimum setting you are looking at losing well over a stop of light, and be careful of cheap ones. They often are soft and give you a colour shift.

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  1. Matt Duclos of Duclos lenses in the states does great work. Most people will know him from his PL tokina 11-16 conversion. He offers a service to declick ZF lenses, and also remount to canon and add a uniform front element so that a single reduction ring or MB clamp ring can be used with the whole set.

    Definitely worth looking at if you are stateside.

    1. Philip Bloom says:

      ah yes Matt is a star!

      1. Austin says:

        Indeed, Matt did a beautiful job de-clicking my 35, 50, and 90mm Leica Rs. Did a quick test and review-

    2. nerdo says:

      If you want to go Dutch, you can check out Kamera Service:

      They ask 45 euro dollars for each lens.

      If you want to go cine-crazy® you should check out the x-circle, it will flip the lens 90 degrees so your AC can see wassup aperture / focus wise:

  2. I understand that manually changing the iris during a shot can be useful to control the exposure. But while doing it, doesn’t it also affect the DOF ?

    1. Philip Bloom says:

      yes it does, but if you are shooting something that is “happening” changing exposure if light changes is essential. Screw the change in DOF!

  3. Francis rene says:

    Any places in canada?

  4. Eric says:

    Actually, I would prefer an iris that acts like the human eye.
    When it gets darker, it opens up. When it get brighter, it closes.
    So exposure remains as even as possible automatically.

    Thus an auto-iris would be preferable, with a manual over-ride when you actually want to control DoF (and exposure gets handled with ISO play).

    Hmmm, now that I think about it….isn’t that called Aperture-Priority?

    1. Philip Bloom says:

      AUTO!!?!?! AUTO?!!? Get off this site and NEVER come back! :)

      1. Chris says:

        Philip just when I was thinking nothing in this article would make me laugh, except the title you write this brilliant comment moderation.

      2. nicholasp313 says:


    2. Don McVey says:

      No. Aperture Priority is when you set the Iris and it stays fixed. Oh, and it’s only for photos!

      What you’re talking about is auto iris. Good luck with that!

      1. Per Lichtman says:

        What we usually think of as auto iris (for stills) is shutter priority. The problem is flicker from micro-adjustments, something that can be easily seen on most timelapses shot in that mode in particular.

        In the case of timelapse people have put a lot of effort into efforts like the Little Bramper (bulb ramper) to set it up to work with light meters that would be intentionally set to limit to slower/smoother adjustments instead of flitting back and forth between settings all the time.

        The problem is that it gets around that by varying the exposure time continuously by using bulb mode, not by adjusting aperture. But if you combined some of that sort of modified light meter approach with a stepless/declicked lens to control the apeture it could potentially work.

        Seems like it would be a way off, though.

  5. Anyone know somewhere to get this done in Australia? I’m particularly interested in the dampened iris ring. I was under the impression that several lens ‘de-clickers’ didn’t do this.

  6. What are your thoughts on pulling exposure using a Fader ND filter?

    It doesnt change the DOF and in is smooth as butter, is there a downside in your ipinion/experience? this site

  7. Don McVey says:

    I just got a mint Olympus Zuiko 135mm f3.5 from ebay for £36 (with iris on the lens)

    Have a few of these cheaper than cheap OM lenses that I stick on my 60D. I don’t know that much about lenses but I get a great image from them. £36!

  8. gecofilms says:

    You can declick your lenses, but if you already have nikon lenses without iris ring you can use an adapter with iris control like this one:
    I use this one with my nex-fs100 and work wonderfull, micro adjustments.

    1. Philip Bloom says:

      not really a solution as that is an adaptor for E mount cameras. What if you want to put nikon glass on a nikon or a canon for example?

  9. I’m also interested in a place in Canada. I don’t really want to send my lenses accross the border, I’m afraid of the possible delays

  10. Depending on the lens, it’s actually quite easy to declick a lens yourself… I’ve done so with some Olympus OM, Leica R, Nikon, and Vivitar Series 1 glass. Dampening can be done with a small (SMALL) amount of silicone grease.

    Of course, that’s talking about a used vintage $10-300 lens… A $1500 Zeiss may require slightly more delicate treatment.

  11. Jiri Vrozina says:

    While i like smooth iris i dislike using ZF Lenses especially on Canons.
    Focus direction is annoying and using cheap adaptors is a problem. Sooner or later they are loose.
    Also Canon c300 Iris control (1/8) is not really smooth at all.
    I own Zeiss ZE lenses.
    50 mm f1.4 is a joke…soft
    New 35mm f1.4 is good, so is 50mm macro and 85mmf1.4
    21mm is great but slow at 2.8.
    Zeiss are crazy not having 15mm wide lenses for DSLRs.

    Finally here is my lens selection for new Nikon d800 :-)
    Nikons 24mm f1.4, 50mm f1.4, 14-24mm f2.8 and 16-35mm f4.0 VR
    Iris is smoothly controlled by 2 buttons on D800 body.

    1. Philip Bloom says:

      always so bullish Jiri!:)

      It’s not hard to get your head around focusing the other direction…also 1/8 whilst not perfectly smooth is a damn site better than 1/3!

      1. Jiri Vrozina says:

        It is difficult for me. One minute i use my f330 and next minute Canons.
        After 25 years of filming it is hard especially if you change cameras all the time.
        Having said all that i really might end up with Nikon if Canon will not release Full Frame DSLR.
        APS-h or c is not an option here. I tired of ruining my wide lenses on non full frame cameras.

        P.S. can you talk to somebody from Zeiss to rerelease 15mm for ZE and ZF ?

        1. Jiri. Buy the old Pentax 3.5/15. It`s an original Zeiss design. And the first type was allegely aspheric.

  12. Chris Weatherly says:

    I really need to send my lenses to Matt. I use Nikon mounts and I could use a life change. Variable ND works, but when working in lower light you can forget about it! And the mentioned color shift is a pain when grading in post.

    Thanks for the reminder Philip.

  13. real men declick their own lenses (and I did it too)

  14. Gum Bum says:

    I just declicked a 14mm Samyang my self! I should add that I am totally useless with tools of any kind and I thought that I had a 50% chance of destroying the lens all together.
    Turns out that it is really really easy and nothing to be scared of.
    Only thing is that the aperture ring is a bit loose but not in a problematic way…

  15. mattdavis says:

    +1 for Eddie the Lens Doctor. I have a couple of lenses from him, and will be sending off a couple more for de-clicking shortly.

  16. Andrew says:

    I have used Eddie on many occasions both to repair and to buy lens from him. I too wrote a review of his service on my website and highly recommend him. The link to my article is

    So between Philip and myself you get a pretty good idea about why Eddie at Lens Doctor is the way ahead.


  17. Philip. You forgot to mention another solution to the problem. By chance I have old zeisses 180/2.8 and 80/2.8 and I know there were 58/2 and 35/2.8. What then? All have preset diaphragm! Many other makers produced in the past some quality glass with presets, Leica for.ex. For the younger folks a little explanation. In old days, before automatic stopdown action, lenses were made with two aperture rings. One set the actual value while the other operated fluidly between the max opening and the set aperture.Voila! Of course the were old but neverless still respectable marbles, wonderfull for those memories oh! memories retro flicks.

    1. stanislaw says:

      Halleluja. Am I right! Voghtlander-Cosina must seen the light as they presented 17/0.95 for MFT with preset
      diaphragm. Now you have both of the worlds. Clik stops for stills. Fluid for movies. On top of that you can set the smallest usable aperture refractionwise as a limit for fluid aperture setting. Old common sense comes to modern usage.
      Hej Zeiss, how about your manual gems? Time for update!

  18. Gum Bum says: I declicked my 35 and 85mm Samyangs as well…easiest thing in the world. And I have researched a bit about how to dampen them. The advise I found so far, was to use grease…grease that doesn’t give off fumes.

    I have found a company that makes grease specifically for dampening (don’t know if I’m allowed to post links)
    It cost around £ that’s gonna be the price for having the entire Samyang range of lenses (the 24/f1.4 soon to be added) declicked and dampened…sweet!

    1. Yea mate, please post that link! any links for how to de-click the aperture yourself?

      1. Gum Bum says:

        As for declicking Samyang lenses (don’t know if it applies to other brands): Turn your lens over, screw the mount off.
        A plastic frame will appear..screw that off as well. Now the aperture ring is exposed…lift it up a bit and a tiny spring and steel ball will pop out. All done! Seriously! Screw it back together.

        Would I do this to a $2000 Zeiss lens? Absolutely!
        Would I apply grease to that same $2000 lens? Hmm..I’ll have to get back to you on that one 😛 I’m gonna start with the 14mm Samyang (not a lens I use a lot) and work my way up.
        The lenses are perfectly usable without the grease…I just think they would benefit from a bit of resistance.

        A few threads debating do-it-your-self declicking: (where I found the Nye grease)

        1. Gum Bum says:

          I want to thank you Philip Bloom for opening my eyes to this. I never considered changing exposure while recording an option on my 5D2…this is great!

  19. I come from a Film and Video backgorund Phlip great posting I like it alot of key points.

  20. I would like to recommend Eddies service as well. Perfect job and a real gentlemen. I did discover one odd thing. Sticking a Tamron and a Vivitar on my D7000 the smooth aperture would only stay where it was put with the cameras battery in otherwise it would try and return to wide open. Very weird.

  21. I was considering buying the ZE lenses for my 7D before I read this article. Glad I haven’t yet seeing how now I have a lot more questions.

    – Right now, I am shooting photography and video equally. The ZF.2 lenses sound great with manual aperture but 1/2 stop increments? No thanks. It sounds like if I get the ZF lenses, I’ll need the modification. Has anyone had any experience with the modified lenses and shooting photography? Does it affect spot metering and if so, how?

    – I’ve also read that using a lens adaptor (such as the fotodiox) creates a small amount of space between the lens and the body of the camera thus throwing off infinite focus a bit. I can’t imagine it’s bad but wanted the input of those who have used or are using it. Also, it looks like Duclos offers a set of ZF.2 lenses with Canon EOS hard mounts. Does anyone have these lenses and what are your thoughts?

    Thanks for the article Mr. Bloom. Keep up the excellent work.

  22. walker says:

    I had 3 old fast FD lenses ( 24mm 1.2, 50mm 1.2, 85mm 1.2) done here – he removed the clicks and took them back to factory EOS mounts.

    He’s in upper Michigan i beleive.

    I originally had them dome for my P&S 35mm adapter, then when the DSLR’s hit …i was ahead of the game. for once.

  23. JoeJITSU says:

    EX3 collecting dust? Put it to good use and sell it to me. I have a family business and with the right price Philip, I might like to buy it.
    Other than that, Love all your work.

    1. Philip Bloom says:

      I do use it for training videos though

  24. nicholasp313 says:

    Hey Philip,

    Would you get your lenses declicked if you plan on doing timelapse stuff too? Does doing this affect timelapse at all?

    1. Philip Bloom says:

      not in the slightest. makes no difference

      1. nicholasp313 says:

        Great, thanks! Your blog is the best. It’s been an invaluable resource. I’m on my way to get the Zeiss Planar 50mm ZF.2 now. Looking forward to it.

  25. mmarshall says:


    I have a zeiss 50mm, 1.4, Canon EF mount.
    I shoot on the GH2, with a Kipon m4/3 adapter.

    I can’t open the aperture to 1.4. Is there an adapter that will allow you to open all the way, or do I need to get the nikon mount zeiss?

  26. Well Philip, I understand that being a very busy man you didn`t comment on my modest answer to declicking problem, by pointing to the old preset lenses. But now see what do we have. The good old Voightlander/Cosina introduces at CP+ MFT 17/0.95 with what? blimey me. A preset aperture lens! It even has by the nature of mechanism possibility to limit the smallest usable aperture before refraction steps in.Wonder why lovely Zeiss manuals forgot what they were doing generation ago.

  27. Che says:

    Any suggestion on where to find a pro nikon to canon adapter in the UK? I’m going to send a coupe of zeiss lenses to Eddie Huston next week but I still have to find something like the Fotodiox Pro here in London.

    1. andbrehm says:

      Just check out Leitax:
      Very nice guy and craftsman.

    2. Bill Gill says:

      I’m uk based and fotodiox got one of their adapters to me in just over a week – i would order with confidence if i were you

  28. andbrehm says:

    For all you people living in southern Germany, here is a great address of real craftsmen for de-clicking lenses:

    I had my ZFs done in no time for €25 (!) a lens. That’s a bargain for the great job they did.


  29. gfilmdawg says:

    De-clicking is a good thing for cinema lenses… using the aperture to ride exposure is very useful. But with the development of the fader ND filters, I’ve had good success riding the fader. The advantage is keeping the aperture
    the same, so the DOF remains unaffected.

    BTW. Philip… love your blog… keep up the good work.

  30. ismaelteron says:

    Hello Mr. Bloom now im making a decision abut buying lenes for my Canon 5D Miii and you talk abut the “Rokinon” lenes quality compare so the Zeiss that i was waning to buy and because “Rokinon” lenes are good price for video and still this brand make a big diference y quality ?

  31. Morts says:

    As I was unsuccessful in finding a ‘lens-doctor’ in Australia I decided to attempt to de-click my Samyang 35mm myself and even though it was not too difficult I might not attempt doing it with a more expensive lens. I did a short blog-post describing the process should anyone decide to give it a go themselves:

    Have a great day


  32. Aisles says:

    Man, the more I think I know about video and DSLRs, the more I realize I dont know anything yet… Manual Iris, I never thought of that! since I’ve always been with DSLR’s so far, and of course the drastic change of aperture during filming is a no go, I just do it and then I just edit it like nothing happend, but in real life sometimes that’s not an option… some day I’ll need one de-clicked lense for sure, by now, I’m saving for some escencial lenses… by the way, I got the 5DMIII and I only got the EF 28mm f1.8 prime and the nice glass but toy-like low budget 50mm f1.8 II (I have some other lenses like the ef-s 15-85mm and EF-s 55-250mm but they don’t work there) … I don’t know what to get next because I want everything!… a 100mm L Macro, a 100-400 L telephoto plus 2 x extender (I like extremes) or a zoom lense with fixed aperture like 70-200… f2.8 or f4… Now that you know what I’m into, what would you recommend for an HDSLR starting point? or you think it’s just up to me?… I also have huge questions about color grading because no one on the net seems to get it right for my taste, but I won’t bother with that… I’m not a pro, so that’s why I’m asking for recommendations! thanks..