8mm Forum: Sankor 13-D anamorphic lens question.

This is topic Sankor 13-D anamorphic lens question. in forum 8mm Forum at 8mm Forum.

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Posted by Tom Photiou (Member # 130) on May 02, 2016, 03:15 PM:

Not sure if it's me being a bit daft,(again),
My Brother has one of these with the bracket to fit it to his Elmo 1200HD. He uses the Elmo 1:1 lens and a 8 foot screen.
Its taken him years to mention this but no matter how hard he tries with this Sankor lens his image had bend at the lower of the image. I have taken a look and i am guessing that this lens is pretty much for a 16mm projector rather than a super 8 machine [Confused]

I myself use the excellent Iscomorphot lens i bought as a kit from Derann many years ago, this one is just perfect.
Here is the lens and also the bracker in place.

BTW, we had this lens cleaned internally by a photographic repair shop so the lens's are all serviced despite the gritty looking body.I personally think he needs to sell this one to purchase a suitable one for 8mm.

Posted by Steve Klare (Member # 12) on May 02, 2016, 03:26 PM:

Hi Tom,

This is what I use for 8mm and I have no troubles.

I do have it much closer to the machine's lens, though. (When I run with a Eumig 800 series I often rest the front of the machine's lens inside the recess at the back of the anamorphic.)

-maybe you are getting some kind of vignetting?

You would think the 8mm image would be a smaller train to send through a tunnel and not so likely to hit the sides! (-Sorry for the railway metaphor, the cleanest one I could think of other than this involved geese!)

Mine is actually Royal Navy Retired: my old friend Tim Christian bought it for me over there surplussed at a really good price, checked it out and sent it here about 10 years ago.

Posted by Tom Photiou (Member # 130) on May 02, 2016, 03:56 PM:

Thanks Steve, i shall have a little experiment tommorow night.(no puns intended [Big Grin]

)

Posted by Steve Klare (Member # 12) on May 02, 2016, 04:02 PM:

I'd try to take it out of the mount and fly it manually!

-maybe try the 'ol books and bag o' rice trick!

Posted by Tom Photiou (Member # 130) on May 02, 2016, 04:20 PM:

will do that, i think your right about it being too far away from the projector lens, the other one i use literally fits inside the outer frame of the elmo lens. Train in tunnel as you say. [Big Grin]

Posted by Maurice Leakey (Member # 916) on May 03, 2016, 03:12 AM:

The rear element on the 16D is 52mm in diameter and is probably for 16mm, however, having said that, there is no reason why I shouldn't work correctly with an 8mm projector.
So I agree with Steve, there is too much distance between the two lenses.
The Bell & Howell anamorphic for my 16mm projectors screws directly into the backing lens, and in the later days of 35mm scope projection the two lenses were kept permanently screwed together.

Posted by Rob Young. (Member # 131) on May 03, 2016, 05:40 AM:

Yes, it sounds like the beam from the Elmo 1.1 is hitting the extremes of the 16D rear element.

The 1.1 lens will go pretty wide (11mm as I recall), so when set for maximum image size it will challenge most super 8 anamorphic lenses. Even my Kowa 8-Z has to be pushed right back so that the two lens barrels meet(KOWA 8-Z was designed for super 8, but still has a 52mmm rear barrel diameter and is very similar to the 16D), if you want to use the 1.1 at 11mm. But that isn't really desirable as you are really pushing the optics too far, even with these quality lenses.

So, either zooming the image smaller (which obviously you don't really want to do) or moving the 16D back towards the 1.1 should help. Bit of a pain as you'll need a new lens holder, but at least it should be solvable.

Posted by Brian Fretwell (Member # 4302) on May 03, 2016, 06:39 AM:

I'd add that the anamorphic looks a little lower than the projector lens which might mean the combination is distorting the beam.

Posted by Tom Photiou (Member # 130) on May 03, 2016, 06:41 AM:

Thanks to all, i shall have a play about tonight and let you see how i got on.
Very helpful [Wink]

BLIMEY, I JUST REALISED WHAT A MAROON I AM, LOOK AT THE THREAD TITLE> [Frown]

Posted by Rob Young. (Member # 131) on May 03, 2016, 12:52 PM:

Yep, I noticed that too Brian and it may well contribute to distortion on the lower edge of the projected image.

Not sure how Tom could adjust the current holder to move the 16-D upward a tad though.

Let us know how you get on Tom.

The 13-D is actually the very rare high quality version. [Wink]

Posted by Paul Browning (Member # 2715) on May 03, 2016, 01:37 PM:

I have the isco lens Tom, also from Derann. I use it with the beaulieu 708 standard lens, but like every one is saying here it does need to be much closer to the projector lens. I do find though that when it is this close the lens, after a while in place the front lens of the lens on the beaulieu fogs up. I have not tried this scope lens yet with any elmo lens, so I've yet to see if this what happens too. An odd one.

Posted by Rob Young. (Member # 131) on May 04, 2016, 02:58 PM:

Interesting Paul; it must be condensation of some kind?

Sounds perhaps obvious, but have you tried making sure the glass on both lenses are at room temperature before projection? Especially if the Anamorphic is kept somewhere cooler when not in use?

I've heard of vapour from prints fogging up the rear element of a projector lens. Actually, Keith Wilton noted this when running B&W prints on the CHC / Fumeo prototype all those years back and commented that he'd also seen this when running B&W prints on an early Beaulieu 708.

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