Dedicated video lenses usually feature stepless aperture to allow for smooth adjustment of exposure. Most still photography lenses, in contrast, feature stepped aperture adjustment. This article demonstrates how to "de-click" Canon FD lenses to get stepless aperture.

Before you continue, note that

1. De-clicking is easy. All you need to do is to unscrew the rear and take out one or two things.
2. The process will not introduce dust into your lens---the optical assembly is sealed in one piece inside the lens.
3. There is a "cheat" that gives you continuous aperture adjustment without the hassle of opening up the lens. All you need to do is set your lens to the smallest aperture, then turn the ring on the FD adapter. The downside of this cheat is you do not have any indication of which f-stop you are at.

With that in mind, if you still believe de-clicking is useful---and I personally do find that being the case---here is a quick demonstration on how to do so.

1. Take apart the lens from the rear and remove parts that cause un-smooth movement

2. Remove the piston

If instead your FD lens locks with a rotating metal ring, you will need to remove the two ball bearings inside the aperture ring.

3. Removing the spring holding the aperture selector

4. Linking the aperture ring to the aperture diaphragm

If your FD lens locks with a rotating metal ring, you will be lopping around the coupling fork instead:

5. Re-assemble the lens. It's done!

I used to buy the focal reducers offered on PV, they have good optics. However, I love the fact this one has aperture blades. Any experience with this one?

I'm on my once in a lifetime around the world trip and my Sony FE 24-240mm f/3.5-6.3 OSS broke down in middle of nowhere in Philippines.

The problem:

• Camera body (Sony A7sII) does not recognize lens aperture and it cannot be controlled. When switching lens on and off and flicking camera power the camera might show the right aperture just for 0,5 seconds and then disappear into -.

• Lens aperture sometimes randomly "hunts" between aperture fully open and closed until it always gets stuck in closed (~f36).

• Focusing works very randomly. Focus mode cannot be changed due to "Lens not attached properly or not supported"

• Still photos can be taken (not in focus) but no video cannot be recorded.

• There is a strange ticking sound inside the lens when camera power is turned on and lens attached.

Tried fixes:

• Contacts are cleaned and no physical damage can be seen on the lens. Other lenses Sony FE lenses work fine with the camera body.

Have you guys experienced similar problems with Sony FE lenses??

I'm truly getting desperate. :(

RARE: 16-160MM CONSTANT F/2 M4/3 CINEMA SPEED LENS IMMACULATE CONDITION

1. INFINITY FOCUS. The lens is made "parfocal", providing proper infinity focus. Minimum focusing distance with this lens is about 3 to 4 feet.

2. PRECISION GLASS. Manufactured in Japan, this zoom precision lens is nearly perfect in optical quality. As the photos demonstrate, the glass on this lens is stunning, though it only resolves 1080p.

3. PARFOCAL. With most zooms you lose focus as you zoom the lens. However, this lens maintains perfect focus throughout the entire zoom range of 16mm to 160mm. (See photos straight off GH2)

4. ZOOM. The zoom throw on this lens is about 55 degrees, the zoom barrel is tight with no play. It is smooth and a pleasure to shoot with.

5. VERY FAST. This is a constant F/2 lens which is an exceptional low light performer. An 8 blade aperture produces a nice round bokeh. The declicked aperture for silent, butter smooth operation. Aperture throw is 45 degrees.

6. NO VIGNETTING. As set up and tested on the BMPCC and the GH4 in 4K in UHD, there is no vignetting anywhere on this lens. This lens covers the 4K image circle on the GH4, but it only really resolves 1080p resolution, you need Canon Cinema lenses to resolve 4K… As you consider, remember that this lens has a CONSTANT aperture of f/2 all the way out to 160mm! Please be aware, the lens has better sharpness at F/5.6... F/2.0 wide open, like any lens, is relatively soft.

If you are interested in purchasing this lens from me, please send me a PM or contact me below... This lens is valued at $500USD, but I am willing to sell it for $400USD and free shipping because I know people like good deals! Besides, I need to buy a Canon XA35 so this lens will no longer be needed by me. You win!

Please visit https://www.dropbox.com/sh/6qy72l557o3h9em/AABsnc2nzu38jiwa8ZyhjgA4a?dl=0 for high resolution photos.

Contact: Brennan Kirkpatrick brennan@infinichair.ca 613-466-0222

Any clue?

The biggest benefit I can think of is that the exposure will stay constant as you zoom. You can fix the shutter speed, focal ratio, and ISO values and then zoom without needing to change them. That sounds great but do we really need that?

With cameras that have Auto ISO available in manual mode can’t you just let the auto ISO control the exposure while you zoom?

Also aren’t all lenses constant aperture, just not always at their wide open apertures? If you stop down to the minimum aperture of the lens then the aperture will remain fixed in aperture priority or manual mode while you zoom even if the lens isn’t a true “Constant Aperture” lens.

What happens as you zoom? Aren’t these lenses still changing the aperture in order to keep it constant? Doesn’t that mean that your depth of field will change as you zoom? If the focal ratio of a not constant aperture zoom lens increases as you zoom in could it then keep depth of field constant as you zoom if so desired? Would that ever be desirable?

Couldn’t a constant aperture zoom lens have a slightly wider aperture or slightly longer focal length if it wasn’t a constant aperture lens wide open? Aren’t they crippling the lens slightly in order to make it constant aperture wide open?

Also what about being parfocal. Isn’t maintaining focus as you zoom more important than maintaining focal ratio especially in cases where you can let Auto ISO solve the changing exposure issue?

I am just curious as to why we insist on having constant aperture lenses. To me the benefits of a constant aperture lens do not outweigh the benefits of a non-constant aperture lens as long as your camera allows auto ISO in the modes you are shooting with.

With that being said the 35-100mm F2.8 is pretty much the only lens I use on my GH4 now. However, I really don’t zoom that often while filming so I am not sure I use it to its full abilities.

• Post photos taken with your vintage manual lenses at wide open aperture, preferably at f/1.4 or faster, but other lenses with slower max apertures are also welcome.

• List the lens, the camera, and the aperture (includes speedboosters!)

I just recently wanted to buy a fisheye lens to filming skateboard videos, but I came across 2 different fisheyes :

• The Rokinon 7.5mm f3.5 for Micro 4/3

Or

• The Rokinon 8mm f2.8 for Sony E-mount (NEX-7, NEX-5, NEX-3...) + Adapter

The thing is I know the Rokinon for M4/3 is going to fit directly on my camera (tried it in a shop), but the Rokinon for Sony is much faster, but maybe a little less wide...

Can you please help me choose ?

Thank you.

Thanks

"Our system can be used with commercially available DSLR cameras and photographic lenses without modification to either. We leverage the fact that defocus blur is a function of scene depth and f/# to estimate a depth map. We demonstrate several applications of our multi-aperture camera, such as post-exposure editing of the depth of field, including extrapolation beyond the physical limits of the lens, synthetic refocusing, and depth-guided deconvolution."

Interesting tech, the lens Is CRAZY!!!

http://people.csail.mit.edu/green/multiaperture/MultiAperture_lowres.pdf

It should give a really nice circular bokeh with the number of aperture blades on it. Might be a great cinematic upgrade for lenses with less than desired bokeh. Has 58mm thread, with a max aperture diameter of 37mm. Clickless lever for smooth change.

Question is, would it work if screwed into the front of your lens and how well? Has anybody tried something like this?

I am selling this VERY VERY RARE great lens in excellent condition!

I am from Hungary, Europe.

I can receive money via Paypal.

Price: 799 USD + 29 USD shipping cost worldwide (as priority and registered mail with tracking code)

Worths to take a look about this rare lens:

http://camerajunky.wordpress.com/tag/carl-zeiss-jena-pancolar-80mm-f1-8/

If anybody is interested, please PM me! ;)

Have a nice weekend for everybody on this forum! ;)

But now we tried the equally fantastic Pana 12-35 and same DP found the same Issue with this lens as well. Is this something well known? I have not heard it from other sources.

Is there any workaround that someone knows about or other zoom that can be used.

Now with an even better Gh3 Coming up and our AF101 still performing well it is à shame not to be able to find good tools. Prime - wise the situation is fantastic ... But Video zoom?

Now THE slow 14-140 does not behöver in this way. But focus by wire is not really good.

THE new Pana zooma just must work... But How can one prevent the aperture to change while zooming?

Leif

http://diydrones.com/profiles/blogs/arduino-control-of-a-camera-lens

Vladimir-- built an Arduino-based pass-through ring (translated) which intercepts automatic lens controls. It’s meant for use with the Canon EOS lenses which have their own electronics allowing control of things like focus and zoom.

It seems like part of the motivation here was to uses the lenses with other brands of cameras. But Vladimir does also talk about the possibility of improving on some of the sensors that don’t perform well in certain climate conditions (think of how crystal oscillators will drift as temperature changes).

The machine translation is a bit rough to follow, but it seems the adapter ring still uses the settings sent in from the camera but has the Arduino clone to translate them into a format that the lens is expecting. In addition to this there is a set of buttons on that small PCB beside the lens which allow for fine tuning the aperture.

Here is the Russian link if anyone can translate or extract better info:

http://www.ixbt.com/digimage/canonautosonyl.shtml

It would be nice to translate GH-2 lens focus commands to say Canon. Then we can have our autofocus and aperture control on a wide range of adapted lenses.

Maybe a Russian speaker can e-mail him to see if he can adapt to M43 to canon rather than Sony to Canon.

Thanks in advance for any help.

Here is a list of lens used at the moment, they all behave the same:

Panasonic - 14-42 - 14 140mm

Nikon: - 135 mm 1:2.8 - 50mm 1:1.8 - 52mm 1:14 - 85-205mm 1:8 - 300mm 1:4.5