16X Manual Lens Questions

[Tony Davies-Patrick]

I've just been talking again to Optex headquarters. What I first thought was a thread for filters or hood on the .7X Wide Angle Optic, is in fact a special thread designed to accept another slightly different .7X Wide Angle Optic, that when both are combined, increases the angle of view from 30% with one element, to 50% with two elements.

The reason why Optex do not actually make a lens hood to fit the Optex is mainly due to problems with vignetting. However, I did find out the size of the thread - and that should be (Optex thinks!) the same as the second Wide Angle outer Optic, which is 93mm.

Now all I need to find is a lens hood with a 93mm filter thread which has a cone that doesn't vignette on the .7X Optex...I think I've got more chance of catching a salmon in the Thames! It looks like I'm going to have to try and make my own ultra-large lens shade to fit, or live without one.

[Tom Hardwick]

I've always thought that this Optex method of combining two single spherical elements to form a powerful wide-angle converter is the wrong way to go. Two elements = 4 more glass surfaces ahead of your VAP.

As you've found out Tony, tiny imperfections in the glass, coating, or minute traces of foreign matter can really begin to shadow the chip at the sort of focal lengths we're dealing with here. Your lens is 5.5 mm at the wide end. With the Optex combo in place you're filming with a focal length of 2.75 mm - that's well under 1/8". The depth of field - even at fairly wide apertures - can come to within millimetres of the front element, and can even come inside it at close focusing distances.

So beware. Avoid using polarisors, UV filters or anything else that presents more air-to-glass surfaces when using these minute focal lengths.

I agree that these very wide-angles can make your shots looksteadier and your hand-held tracking shots look devine. Now one thing you didn't mention was the barrel distortion. Any comments?

tom.

[Tony Davies-Patrick]

I was recently out on location, testing my lens combinations again. A lot of the time was spent near and around water, testing for reflections in bright conditions, using the polarizer, etc, and then followed by an afternoon testing both the Manfrotto stability, and Reinhardt windsock on the mic during really strong winds blowing across open heath land and hilltops.

To really put the 16X manual and Optex through its paces, I did a lot of shooting with sunlight either in or just outside the frame. It soon became obvious that my setup just didn't cut it. The glare was bad in the Optex, and even showed in a lot of shots using the 16X manual on its own.

I've spent a long time looking at options for shading bright light from my lenses. I could buy an expensive extension hood or bellows shade for the 16X lens, but the large Optex Wide Angle Optic would need a larger and even more expensive shade.

I looked at lots of different options from barn doors to various Matte boxes - all would either vignette or would simply not fit, even with adapters. Above all, the cost for a very large Matte Box system seemed madness!

I thought that this Cavision shade might do the trick, fitted on the outside of the Wide Angle Optex:

http://www.cavision.com/LensHood/LH100w.htm

But it is far too small and wouldn’t stop all the bright sunlight.

Then there is this:

http://www.cavision.com/Mattbox/Mattebox.htm

Or a French flag/Shade set-up such as this:

http://www.cavision.com/french_flag_for_3x3.htm

Then I looked at the cinetactics model:

http://cinetactics.com/mb100m-ffl.php#

Now, this looked closer to what I needed; however, the system really has to fit over a hood, and the tiny rim of the Optex is just too narrow. Not only that, but all of the options so far cost king’s ransom, considering what they are made of.

In desperation, before I forked out good money, I cut out a section of black plastic, to the shape of the Cinitactics Matteblox kit (but in larger pattern), and then tried to fit it to the Optex. No way, it just wouldn’t hold in place or work well…I’m glad I didn’t order the complete kit plus adapters etc!

Another thought went through my mind - When I was filming beside the lake - with lens pointing slightly towards a sun that sent shafts of bright light across the front of the large glass element (making the footage look like I had a fog filter over the lens!) - it only needed my hand held out high and to the front of the lens, to block out all sparks of sunlight…all internal glass reflections disappeared, bringing back full contrast and deep, saturated colours back to the scene.

It is OK to hold out your hand for a static scene on a tripod, but certainly not for slow pans or handheld shooting etc. My mind span at different options…then I thought of a ‘flag’ held on an extended arm. Ebony make such a model for use on Large Format still cameras, shown here:

http://www.ebonycamera.com/acc.html

I ordered one to try. When it arrived, I cut out an extra-large wide crescent shape from a lightweight, semi-stiff sheet of matte-black plastic, and then slipped this between the clamp jaws of the Ebony Shade Holder (The shape, size and stiffness can be made to your requirements and any type of photo shoot).

The Ebony Lens Shade Clip also has a hotshoe foot, so fits nicely inside the Canon XL1s hotshoe mount. The extension of my Light Waves Systems SI-XL1 mount pushes the Ebony clip forward beyond the long 16X manual lens combined with the Optex Wide .7X optic, allowing full shading from bright sunlight, and the small ball & socket joint of the Ebony allows for adjusting the ‘Shade’ to block out light from any angle.

I went out on a really bright and sunny day to give it a full testing on my 16X and Wide Angle Optex. All I can say is…Superb…and it has saved me a packet of money!
The system is so flexible and so lightweight, I can now use it for most of my outdoor shooting and with any lenses I choose.

[Tony Davies-Patrick]

I am looking to slow down the servo zoom on the 16 X manual lens for some shots (without clicking the zoom manually off servo control). Is it possible to slow the servo zoom right down to a very smooth creep, similar to the autofocus 16X or 20X, by using the ZR-1000, or Vari-zoom?

Ken mentions in his report: "...The 16x Manual Servo lens’ variable-speed servo is capable of producing a good, slow creeping zoom ..."

On servo, the zoom is just one fairly fast speed, so "variable servo zoom" does not seem correct...or did Ken mean variable with the use of the remote?

[Chris Hurd]

This lens will zoom fairly slow, though not as slow as the white 16x auto lens. On servo, you should have a feathered zoom with about eight distinct speeds. If you're only getting one speed, it's most likely because you have the camera's internal menu set to govern that zoom speed, so you'll need to change it.

The Canon ZR-1000 will allow you to dial in the slowest speed the lens is capable of, and maintain it or change it as you see fit. These controllers are an absolute neccessity in my opinion, they're well worth the cost.

[Tony Davies-Patrick]

Chris, Thank you for your answer, it has helped a great deal!

[Dean Orewiler]

does anybody know where I can find the instructions for the 16x manual zoom lens??

[Richard Alvarez]

check your mailbox

[Dean Orewiler]

I appreciate it !!

[Steve Rutherford]

Ok here's a question about DOF.
I've read the articles on the 16x lens but my question is about DOF. Does the 16x have shallow DOF like the glass on the "big" cameras? I realize how deep this question can be but I'm looking for answers from users of this lens...

Thanks
Steve

[Mike Teutsch]

Originally Posted by Steve Rutherford

Ok here's a question about DOF.
I've read the articles on the 16x lens but my question is about DOF. Does the 16x have shallow DOF like the glass on the "big" cameras? I realize how deep this question can be but I'm looking for answers from users of this lens...

Thanks
Steve

I think the one word answer is, no! See this thread and others, for the whole story.

http://www.dvinfo.net/conf/showthrea...al+depth+field

Good luck----Mike

[Steve Rutherford]

Thank you Mike,,, that's all I needed,, have a great one

[Mike Teutsch]

Originally Posted by Steve Rutherford

Thank you Mike,,, that's all I needed,, have a great one

Also see this thread:

http://www.dvinfo.net/conf/showthrea...hlight=dof+16x

basically the longer the lens the better for DOF.

Mike

[Charles Papert]

It's not the lens, it's the size of the imager that determines depth of field...as long as you are using a 1/3" camera (XL1, DVX 100, the HDV cameras, etc.) the depth of field will be the same on all regardless of which lens is in use. This is why devices like the Mini35 and it's knockoffs have become so popular, it's the only way to get the shallow depth of field on a 1/3" camera that one would expect from a 35mm size imager.

[Tony Davies-Patrick]

It also depends, along with the mm length of the lens used, how wide the aperture/iris opening is set.