35mm adaptors dead?

[Simon Wood]

I bought that Mini35 from Michael Galvan at $700! Couldn't say no at that price because I used to drool over them a few years back when they were worth thousands...

I'll have to pick your brains about these devices once I get a hold of it!

[Bob Hart]

Dennis.


It's that way now that I have to regard the 35mm adaptor season as a savant period in my history. Like all good things that come, then yield their place to something new, 35mm adaptors in such a relatively short period had had their day it seems and so too, my own small moment in history as a prolific though unqualified commentator. With many coming onto the used market at discounted prices, they remain a valid tool for people who remain costed out of the new DLSRs until the first generation of those are passed on in favour of the next big thing.

However, people should not forget the validity of the purpose of the immediate ancestor, a groundglass based director's viewfinder, designed and manufactured by P+S Technik.

With an eyepiece dioptre in place of a camera, an internal framing mask, the mounting hardware replaced by a handgrip, press and hold triggerswitch and for some, a relocated battery compartment, all the image-erecting ( flip ) adaptors would be quite satisfactory as 35mm director's viewfinders for use whilst the camermen and DOPs fret and sweat over their recalcitrant DSLRs.

The existing alternative vendors might make an extra few dollars from their past adaptor sales by offering dioptres to go on back of their adaptors in place of the video cameras. - But please, no dirt-cheap single element ones that go soft in the corners, which would kill off that market very quickly.

[Chris Barcellos]

I have a shelf full of disks, glass slides, wax, vibrating motors, and potential adapter housings that were part of my days of trying to beat the Letus, Cinevate and Redrock adapters with a rig of my own. I built a working spinner out of the Redrock workbook, using a Cinevate lens. I was almost there, I spent a lot of time doing that. I also worked on a Letus35 with improvement. I shot several shorts, and one 20 minute epic that is yet to be edited by the producer. That was a six day shoot, complete with daily crashes on the borrowed Letus flip adapter-- things like the vibrating screen stoping intermittentily with overheat or due to bad solder job, or the set screw letting go and one my my primes falling into a reflecting pool.....

I finally broke down and bought the Canon 5D when it was first out. But even there, wanting to improve on the product, I started working with the Magic Lantern crew to get the camera more film worthy.

I actually am glad I can buy the Canon T3i or the GH2 for less that I could buy one of the better adapters in the "olden days". I doubt seriously whether I could ever have gotten the images out of my DIY attempts that these cameras can give. Yes, there are issues, but then, I still cringe at the frozen grain pattern that was streaking through some of my films with those 35mm adapters.

[Bob Hart]

If I get off my backside, bother to go buy a lotto ticket and my cargo plane comes home and brings moderately valuable good things for the people, I would be tempted to buy a Sony F3.

Alas I need to pull my head in, cull my wishlist of indulgences and live within my means.

I was able to get the Letus Extreme working well but there was always that nagging doubt, will it see out the production or lay down. As it was, it never did die and I had no troubles with it.

Dennis Wood's Cinevate Brevis looks good on the SI2K with the Cinevate varifocal relay. The practical reality is giving up some ease of operation on what is already a heavy camera, when the integrated camera/record unit is used. Super16 ultra primes get you much of what you want in sensible shallow depths-of-field anyway.

The original two flip AGUS35s I built from plumbers pipe and endcaps are now in the shed in a plastic storage box. I wonder if I can persuade the museum to take them.

"Those were the days my friend,
I thought they'd never end---"

Now that shows my age doesn't it?

[Bob Hart]

Locals honing their action genre skills. The guys are getting more adventurous with each project.


They used a Letus Extreme and Sony PMW-EX1. The overlay scene with the girls watching the video I think was likely shot with a Canon 7D that one of the crew bought after the initial action shoot. Their subsequent projects have been done with the digital SLRs.


http://www.youtube.com/watch?v=X-rNu81402A

YouTube - Surfaced Teaser


Grabs ex-facebook.

[Bob Hart]

Here is a link to a website for "Bellflower", an indie movie which screened at Sundance. It was shot on what appears to be and one would have to describe as, the mother of all groundglass adaptors.

It looks like it might be based on large format plate camera imaging and we thought Ted Ramasola and others were going a bit extreme with medium format developments. Large format camera tech brackets across two centuries.

Coatwolf

From a historical sentimentalist standpoint, the camera they used ( very early SI2K by the look of it ) and the alternative 35mm groundglass based adaptors, had their kickoff here on this very forum as did the RED system.

I don't know what waits around the corner in five years time, of a semi-opensource flavour but assuredly, the chances of it being discussed and matured on this site will be pretty good.

[Bob Hart]

Here is another movie, made on a low budget with a guerilla cast and crew and EX3 and Letus Ultimate adaptor.

The title is "MONSTERS". It is in DVD release and the extras are worth a look. The website is here :-

MONSTERS THE MOVIE

[Bob Hart]

I have been a bit remiss in not doing this sooner but have been waiting for a suitable poroject to come along. A little 3 minute movie will happen in a pine forest in the next four weeks or so.

There's lots of linear texture in the trees and ground litter which would provoke moire and lots of movement which will provoke rolling shutter and lots of contrast likely needing deep dynamic range. The 35mm "look" is desired. The budget is near to zero. Don't we here in the west like to punish ourselves.

So chasing for the best of all worlds, we will be giving the SI2K plus Cinevate Brevis and Dennis's prototype varifocal relay a try.

[Bob Hart]

Here's a few location scouting stills for "Professional Hero" a 3 minute medieval short being directed by Matt Barron in Western Australia.

Still minding up on whether to do it on the SI2K on a 35mm adaptor or direct-to-camera or with the EX1/Letus these frames were shot on. - I don't have a digital stills camera. The groundglass motor was not switched on. I also have not done an alignment on the groundglass since I cleaned it last, hence the softness in right side of frame.

An ample illustation of why you don't hire me as an operator, short sight and needing close-up glasses which I had left behind. The SI2K spoils you as it has a sharpness by printed numbers focus readout which you can call up on the screen.

[Frank Ladner]

Originally Posted by Sanjin Svajger

Yes it's a hassle to use this adapters BUT in no way is the 7D or any other dlsr for that matter a replacement. Cmos skew, aliasing, form factor, acquisition codec, zebras, waveform, etc. etc. Even with the new cameras coming out (AF100 and F3) I'm still going to buy probably a new adapter. Even this new cameras have cmos related problems. I for one can't stand looking at skewed video. I'm allergic to it!

Sorry, don't wanna derail this topic. It just warms me up when somebody mentions this dslrs as a professional tool.

Anyway the Merantau trailer looks nice despite the bad rez...

I use a Canon 7D and t2i, but I feel the same way. Particularly for camera-tracking / effects applications (even with care in camera movement). In these cases, rolling shutter skew really messes things up.

I miss CCDs, but CMOS sensors are cheap, so we're seeing lots and lots of 'em.

At any rate, I feel that skew and moire are the biggest reasons to opt for DOF adapter + small-chip CCD camera. ;)

[Finn Yarbrough]

I would like very much for them not to be dead... particularly since I bought one new about six months ago. Since then, I have become aware of some of the limitations, and I hope that a veteran here might be able to help me. I shoot with a JVC GY HD200u, which is a 3ccd 1/3" shoulder-mount. I have the Letus Ultimate and Letus 1/3" short relay lens.

My problem: how do I minimize the vignette? I find it extremely distracting all the time, but particularly when shooting indoors, and particularly when introducing camera movement (when the image is still, the eye doesn't seem to pick up on the fall-off as easily). I am using old Nikon still lenses, formulated for film--is that the problem? I know that they were made for lower resolution specs...

I can't just zoom in past the vignette, because the relay lens is fixed. Has anybody else dealt with this?

[Bob Hart]

Finn.


Could you advise which Nikon lenses you are using.

Anything which is no faster ( lower aperture numbers ) than f2.8 may be likely to vignette. Also, did you buy in the Ultimate together with the 1/3" relay as a kit or separately.

[Finn Yarbrough]

I use a 50mm f/1.4 Nikkor prime, and a wide (20-35) and telephoto (80-200) zoom of the same era (c. 1990) that are both f/2.8

I did buy the relay lens from Letus together with the Ultimate.

[Bob Hart]

This one is counfounding me a bit. The vignette I would expect from f2.8 zooms as these typically have a small exit pupil on the back. However if you are getting this from the 50mm f1.4 there is something else at play. Unfortunately I have not had my greasy hands on the direct 1/3" relay for the JVC GY-HD*** camera family. I only ever set it up with the stock Fujinon which was an awkward arrangement.

With the 1/3" relay lens removed, is there in back of the Letus Ultimate, what looks like a magnifying lens or is there a flat glass surface which is the rear face of a prism inside of a rectangular frame?

My understanding is that the direct relay lens may be able to view the groundglass through the adaptor prism path without need of an achromatic dioptre between the relay lens and the prism. If this is the case, then the extra dioptre in the path would complicate matters and perhaps expand the view of the groundlgass and include the vignette from the Nikon lenses which might not otherwise be apparent. However I cannot be sure of this.

A means of checking would be to take the relay lens off the back of the Ultimate, mount the relay lens on the camera, position a focus target, a piece of paper with gridlines drawn across a 24mm square on it about 7-8" from the camera focal plane and check if sharp focus can be had through the relay lens onto this target. If there can, then likely there is no need for an achromatic dioptre in back of the Letus Ultimate.

In this state the target will appear upside-down.

The Letus Extreme/Elite/Ultimate from my vague recall, provided in the kit for fixed lens cameras, an approx 4+ power achromatic dioptre to enable close focus on the groundglass.


If there is an achromatic dioptre in backof the Letus Ultimate and yet viewing directly through the relay lens onto a target without the Letus on front of the camera and you can get a sharp image from the target, then the next step is to remove that achromatic dioptre from the back of the Letus Ultimate, assemble the relay lens plus camera back onto the rear of the Letus Ultimate with the Achromatic dioptre now not in the path and see if you can get a sharp focus on the groundglass and an adequately sized frame of the image conveyed onto the groundglass by your Nikon lenses without the groundlgass texture being too apparent.

That achromatic dioptre is a bit delicate and tricky to deal with. The glass compound element looks like it is bonded by UV cure adhesive or a two-part hard adhesive like aradlite or similar into its threaded rim. If you shockload or distort the screw-in rim the glass is mounted into, there is a risk of cracking or spalling the edge of that lens which will ruin it.

The best method to remove that dioptre is to use the proper Rolyn spanner and tips which fit. You could make up a simple plate wrench but take care that there is a small arch in centre of the wrench to clear the surface of the glass so you dont gouge or scratch it and tape over the edge of the plate wrench to the full width of the rim so that it does not slip across and scratch the glass. Do not use two screwdrivers and a torque bar to turn them. They will be too uncontrollable. Most definitely do NOT use a screwdriver and hammer method to chisel the rim to unscrew it. The shockloads will ruin both the achromatic dioptre, the small subprisms of the compound prism and even the groundglass disk.

Here is a link to a clip related to the Letus Extreme which is similar but not identical to the Ultimate. The clip gives you a look inside the guts of the prism enclosure which is near identical. I had modified this one for x-y axis adjustment. Your Ultimate has x-y-z axis adjustment built-in. A short shot shows me removing the rear achromatic dioptre with a Rolyn spanner.

ROIDING THE EXTREME. - ADDED LATERAL CENTERING ADJUSTMENT. By Bob Hart On ExposureRoom

Both are near identical from the rear to the front of the prism enclosure. Do not attempt to dismantle the front off your Ultimate. You will only ruin it because it is too tricky for the average punter to tackle.

[Bob Hart]

Before you go screwing and spannering, maybe try this test first. Set the relay lens iris to its widest aperture, as in lowest number and use the Nikon lens iris only for controlling light. If this makes the vignette go away then you might have to opt for ND filters on front of the Nikons with a mattebox to control overexposure.