DIY adapters for RB645 and 35mm lenses
 

Im posting this to share my experience with other DIYers on the pros and cons of each setup.

I first made the mid format adapter and with the help of people in this forum was actually able to have it work. I have used it for corporate work and for a TV spot. The image on the GG is big and manageable to "hit" to avoid vignette/falloff.

image on GG is 36mm x 24mm.

After several real world uses i found the limited availability and variety of lenses as its major con.

I then proceeded to fabricate a 35mm adapter for the nikon mount.
Lenses are easily available. I used a different and finer GG this time.

The adapter size is much smaller because of the small diameter of the GG.

I can use our photo department's wide array of 35mm lenses especially our old manual Tokinas, Sigmas, Tamrons and Vivitars.

The available accesories allowed me to use a nikon m2 extension tube as a lens mount and a gutted polarizing filter as a locking mount that engages the achromat at the rear.

Im "cheating' on image size on gg at 30.5mm x 18mm to maximize image size (concentrating on optimum image that falls within the TV safe area).
below is a side by side pic of the two adapters for comparison. and grabs of a bokeh test using the 35mm adapter 50mm nikon lens at f1.8 and a macro shot using 105mm f2.8. a wide shot using a sigma 20mm f2.8.


Ted

Ted.


What power close-up lens (achromatic dioptre) are you using?

I found that the 7+ was best for a compact handheld portable adaptor but the best results I get are from using a 4+ and sitting furthur back off the groundglass.

The camcorder zoom for the 4+ has to be all the way tele to 54mm and this loses a little more light than the 7+ arrangement which requires the zoom to be no more than 45mm.

The "Tears in the Rain" behind-the-scenes clip on YouTube was shot with the longer setback 4+ arrangement. It is a backbreaking swine to handhold though.

Your edge softness I suspect may relate to the relay path - close-up lens and camcorder lens combination. It may be helpful to position the close-up lens closer to the front element of the camcorder lens if you can achieve this.

I have used my "Sony" evolved adaptor on a JVC HD100 via its standard Fujinon lens.

I actually fastened the close-up lens on front of the standard Fujinon focus barrel itself rather than use the 82mm filter mount as this remains in a fixed position relative to the lens itself which moves forward or backwards with focus movements.

Mounting the close-up lens on the filter mount does not allow the close-up lens to be close enough to the Fujinon's front element to work properly.

The 7+ dioptre I used was a 58mm filter diameter size threaded mount inside a 72mm sleeve. This was crudely attached to the front of the Fujinon's moving focus barrel.

I did not see any edge softness with it but I did not test extensively as the JVC HD100 owner has the real thing from P+S and does not need to use my adaptor.

If you can get your dioptre closer to the Fujinon, I think your edge softness may go away.

You could probably afford to give a little of the image area away, maybe come down to about 28mm wide which is what the 4+ and full zoom does for me with the Z1 and still keep an adequate area for the TV safe area.

This might require you to go to a finer grind on your disk. I note a few arcs on the pliers and spanner image which suggest the grade is yet a little coarse.

Otherwise nice dense colours and contrast.

Bob

thank you again for the great assistance you provide.

the achromat is from dennis wood, i believe he told me its a 10+, it has a 72mm thread.

The suggestion you gave me provided significant improvement on the soft edges. Im attaching two charts.
after removing the achromat from the stepdown ring i attached it directly to the adapter's rear via a series of empty filter rings. setting it farther from the gg at 78mm or a notch more than 3in.

sharpness improved at the sides even beyond the TV safe areas while still giving me 29mm image width.

the moving of the achromat deep into the focus barrel also diminished significantly falloff.

Many thanks for your critical inputs Bob.

Ted

Ted.

You have a significant improvement and maybe as good as it will get with the 10+ which might be a bit strong for the Funjinon unless you can get it a little closer inside the front of the Fujinon lens. The 10+ is a necessity otherwise the non-flip adaptor-camera combination becomes unworkably long.

With the Century 7+ I actually had the 72mm threads bedded into one of the ridges of the anti-reflective plastic area in the rotating focus barrel.

If you buy in Dennis Woods' flip enclosure you may be able to come down in power of the achromatic dioptre which may help, inf fact you may have to if the path becomes too long. My home-made is a flip using prisms which is why I had to stay in the 4+ to 7+ range which is roughly 8 inches and 5 inches setback, physically shorter with the prism foldback of course.

Dennis may also have a condenser in there between the achromat and the groundglass. You would need to ask him about that. P+S Technik also seem to have come down in favour of lower power and longer setback for their direct relay versions. I have not seen their setup for lens-in-camera styles.

The Pro35 has an optic behind the groundglass. I don't know if it is there in the Mini35, but the setup is similar.

Still, within the TV safe area, what you have is useful and careful composition and framing should taske care of the corners most times.

Bob,

My first point of reference in my setup was the chart you posted indicating diopter power --distance from gg---camcorder zoom. You indicated 3in distance from GG. After applying the setback of the diopter by removing it from the step down ring and placing it inside snuggly against the fujinon focus barrel it changed the distance from gg significantly.

The previous chart i posted still has soft sides and corners which is enhanced when using wide lenses. By shortening the GG to diopter rim distance to 70mm or 2 3/4 inch i was able to produce sharper edges and corners.
The 70mm distance is based from the front(matte) side of the gg to the rim of the 10+ achromat.
Otherwise,depending on gg thickness, in my case its 1mm, its 69mm distance from the back surface to diopter rim.

Image captured on GG increased slightly to 32mm x 18.5 mm

Im attaching grabs and a chart, this time i use a white backed chart to better aid me in avoiding falloff.

Ted

Like all R&D, things get better in smaller increments beyond the first giant leap.

You still have some soft corners but this may be related to the larger 32mm image width.

I have about run out of ideas. The only last thing I can suggest is to perhaps to to set the "groundglass to front of lens" distance so that the Fujinon lens is as close to infinity focus as you can get it but still keep just a little for final focus trim with the lens barrel focus adjustment.

Don't use macro-focus or the backfocus on the Fujinon lens for the final trim. Those functions both use the same retrofocus element.

It might be worthwhile emailing Dennis for his "groundglass to front of lens" distance. The elusive last few percentage points of image quality may be related to adding a condenser element, if his optical path was engineered and not a mix and match of available trade parts.

Beyond that, you may have to zoom in that little bit closer and shoot a smaller groundlgass image. Zooming furthur in brings the front element of the internal travelling group that bit closer to the achromatic dioptre which might help with the corner softness as well. At 28mm width, you will still be 2mm either side wider than the standard academy frame.

I never tested my arrangement to a 32mm width as my prism path comes in on the sides before then. I have hobbled myself with cost cutting by using identical prisms of only just enough image width to clear 28mm.

In an ideal world, I would spend on two prisms of different sizes or a a prism-mirror hybrid with larger mirror pair a la Mini35. Unfortunately, the ideal world and my financial means are not in harmony.

Out of interest, in your kit of stills lenses, do you have a 55mm f3.5 Micro-Nikkor. The Micro-Nikkor can focus to 8.5 inches. But as a non flip direct relay, it would be a bazooka with no real advantage over the Fujinon/achromat for overall length except for possibly sharper image and better edge to edge sharpness. You would lose some light performance as well.

On another thread for Letus, a user has fitted another Nikon lens with macro to his JVC via a lens adaptor to use as a direct relay like Quyen does with the Minolta prime and reports good results.

His lens may be a zoom which might lose a bit of resolution and some light but this might be offset by the smaller 1/3" CCD shooting through the centre. Hopefully he will publish more details and some grabs.

That may be an alternative option for you to examine.

Bob,

I did some tests with the fujinon settings and found out how much the iris settings on the 16x can affect the image from the adapter.

Speaking of the letus extreme, Luis Caffesse over at another forum
posted his tests with a res chart. Here are the links to his test with and without the letus using the HVX and zeiss 50mm t1.4.

http://www.pitchproductions.com/pics/HVX-RES.tif

http://www.pitchproductions.com/pics/LETUS-RES.tif

I then took out a similar chart and framed my tests same as his and found some interesting results.

My DIY adapter was able to come close to the letus especially in the corners.
The soft falloff on the letus is wider.

Using the same opening at 1.4 on the 50mm i had I achieved a sharper corner image(take note of the '16:9' text on the chart corners) when i stopped down the jvc to f11.

at f2.8 on the nikon and 5.6 on the jvc is similar to the letus+hvx chart.

Pushing the fujinon for comparison, at f5.6 nikon and f1.4 on the jvc the image fell apart.

In my set up, macro is fully engaged, and focus is at infinity. I use the zoom ring to achieve focus on the GG.

Im attaching the charts below to campare with the charts on the links.

Regarding arcs on the image. Heres my test results.
Lenses 20-40mm f2.8, 50mm f1.4, 85mm f2 dont exhibit the arcs up f4.
Lenses 105mm f2.8, 200mm and above exhibit the arcs.

Ted

Well what is there to say. There's no disputing the test charts.

That's the popular notion of f5.6 or thereabouts camcorder iris being the sweet spot in groundglass relay, shot up the butt like a garden thrush, leastways in this particular lens/achromat combination.

The edges seem square and correct so the spacing between the Fujinon and achromat seems about right. What zoom have you got the Fujinon set to? I think it is a rectilinear lens which means there will be diagonal stretch in the corners to keep straight lines straight anywhere in the frame. If there is any softness in the corners, a rectilinear lens will amplify it.

I could not get the .tif files to come down the pipe, probably a bandwidth thing this end.

Bob,

Zoom setting on the Fujinon is slightly above the 20 mark. Say the white line points at the rear end of the zero.

A funny thing i discovered about the nature of lenses is that all our long lenses from 105mm up to the 300mm seem to show the arcs. Is there something with the optics in them that makes this happen? Or is the narrow light path the culprit?

But anyhow, knowing the parameters i can work with through these tests will allow me to rest easy on an actual shoot.

Ted

20. That's wide compared to my setup.

I did observe the Fujinon seemed to require a slghtly closer GG position than the Sony Z1 for the same zoom position, in my case closer to 50.

This may be due to different specification for the "on-chip" lenses CCD cameras apparently have between different manufacturers. It is tech info I do not know at all.

It is a contrary business. The wider lenses provoked the groundglass artifacts on my setup. If there is any oil gets on a Mini35 GG, the wide lenses provoke that. Yet on yours it is the long lenses.

Your groundglass textured surface. Is it on front face of the disk closest to the SLR lens or the rear face of the disk? Mine is on the rear face.

The textured Surface of the GG faced the SLR lens. You think i'll have better results if i invert it? Conventional knowledge do dictate the matte surface faces the light source.

I think the jury is still pretty much out on which way is best for the groundglass. My personal preference is to have the groundglass texture facing the camera.

Film emulsions of course face the lens.

I have no scientific reasons to back it up other than to hope multiple generations of diffusion and reflection within the groundglass itself are less evident as a halation artifact.

My half-baked theory is that the groundglass texture itself might hide from the camera's clear optical view, half a generation of any clearly defined reflection within the groundglass back onto the texture.

As to your arcs. They are quite sharply defined. My guess is that individual large spots or large pits might be making them.

It might be worth experimenting with pinpoint spots of water ink, diluted down to about a mid grey with a bit of white PVC paint or some typewriter correcting fluid darkened to a neutral grey.

Dip into it with a tooth pick and spot just into the pit itself without going over onto the adjacent area of the glass.

If you are using a plastic disk, this might make trouble for you as plastic is harder to clean off without damaging the texture so you might leave best be and not try to change things.

Bob,

I opened my adapter cleaned the GG, experimented inverting it.

I found some big specs on it and blew them out but small arcs remain at small apertures using long lenses.

The inverted GG produced same results as far as resolution and gg induced grain goes. It might introduce different flare characteristics when light hits at an angle, didn't test that and inverted it back.

In relation to the corners improving when the relay lens is stepped down, i'm attaching a "chart", of the tests results on corners after i recalibrated my focus on the gg. I actually gained a little bit on f5.6 from my previous test, but f8 and smaller is best.

I hope this will also help those who are new at using adapters since i think the principle also applies to the "branded" adapters.

Ted

Another Small Increment
 

Bob,

Quoting your earlier post;
"Like all R&D, things get better in smaller increments beyond the first giant leap."

I made another small increment and this seems to confirm what you said that I should zoom in more on the gg.

I hesitated doing so since I thought I got the optimum balance in edge to edge sharpness and light falloff. However I discovered darker corners outside the TV safe area which flows into the viewable area when images are subjected to extreme contrast adjustments in post and when using very wide lenses.

Im posting a group of images below and the settings on the fujinon for you to see if i'm nearing the settings that you expect in this set up.

I also suggest to DIY'ers out there to do a "plain wall" test to manage falloff.

Your help and comments Bob really show your experience and altruism in these forums.

Best wishes for the new year.

Ted

Ted.

Looking good. You may have also recovered a little more corner sharpness along the way.

You should be able to do chroma key work with it now.

Does the option for small adjustments with the zoom for composition or effect remain? This is one feature I like about relay via the camcorder's own lens, which compensates for the awkardness of the longer arrangement.

All the best for the coming New Year.

Once I hit the focus on the GG using the zoom on the fujinon i usually tape it down since its hard to get the focus especially outside the TV safe area.

I also added 10mm worth of filter rings between the GG and achromat to allow me to zoom in a little bit while keeping the achromat snug against the fujinon front element.

The zoom adjustment really cant go far from the ideal target of edge to edge focus. A little deviation and the sides or the center go off focus.

Its really like walking on a tightrope.

I plan to make a "mamiya 645 lens-to-nikon mount" so i can flexibly use the mini35 i made to accept the mid format lenses, this way i will carry one adapter housing but "flexible' to use 2 lens types, i assume i'll just 16.8mm in distance from the rim of the nikon mount to comply with the 63.3mm flange depth.

Is this feasible?

Ted.

That is precisely what P+S do with their Mini35 and Pro35. They use a bridgepiece between a universal mount and whatever mount the user chooses which is fitted to the bridgepiece which is a custom added distance for each mount type toi make up the correct flange to focal plane distance.

It just happens that the universal mount is PF profile but in its universal role, the flange of the universal mount is much closer to the focal plane than the PL lens mount's 50mm or thereabouts. (not sure of exact distance).

It therefore gets a bit confusing because a PL mount lens will go straight on to the universal mount but the backfocus is then way off. The PL mount therefore is actually a PL mount at both ends which adds space to make the flange to focal plane distance correct for PL mount lenses.

So for your purposes, to keep it simple, the universal mount can be the Nikon mount and the Mamiya mount with its longer flange to focal plane distance would be a bridgepiece with Mamiya mount on front and a Nikon rear lens end on back. You would also be able to make a Nikon to PL Mount bridgepiece which would be a handy option.

There is a remote chance the edges of the fitting which goes inside the Nikon mount may obscure the corners of the larger format image but I don't think so.

The word "universal" that I use is my own. P+S may use another definition.

2 lens formats in one adapter
 

I finished the 645-to-35 mount for the mamiya 645 lenses.
Respecting proper 645 flange distance i can now attach the 645 lenses to the fixed nikon mount lens adapter.

The mount has a locking pin to prevent the lens from falling.

Though the 35 adapter cant produce the same image size as my dedicated 645 adapter, which gives a 42mm x 24mm image on the GG, the 35 adapter can still give a bigger image on the gg when using mid format lenses.

Im attaching photos below and a chart showing the difference in gg image size.

I was motivated to do this because i felt i had to utilize the large image of mid format while still allowing me the flexibility of diff 35mm lenses, without carrying 2 different adapters.

I imagine you should be able to harvest better centre-area definition when using your widest medium format lens compared to the 35mm stills lens for the same field-of-view.

What quality of edge sharpness from the medium format lenses are you getting with your hybrid setup?

kindly ask for information
 

kind Ted Ramasola,
I'm a student, and learning for video. from my relative, i can get several mamiya 645 lens, such as 85mm/f2.8. and wish i can attach these lens to my Sony V1.
how can i get the information for DIY ?
thanks in advance,
gracias,

agatha

Agatha,

Theres a ton of information in this forum on DIY adapters, this is where i got my information.

Decide on these things about your adapter. Static, Spinning or Vibrating.

I made two kinds of adapters, the first is purely for the mid format, the 2nd was meant for the 35mm lens but evolved to this 'hybrid' that will allow the use of mid format lenses.

As to making a diy lens adapter you must decide which format you will be using and for what needs. It would require certain skills at machine shop tools and some electrical soldering as well.

The initial prototype i made is still posted here,

http://www.tedramasola.9k.com/photo.html

the close up lens indicated in the photo has since been replaced by a higher quality 10+ achromatic diopter from cinevate.

In my adapter there is a 5.9 volt motor thats holds and spins a custom cut "ground glass" from a frosted plastic material.

Try to decide on the housing or casing that you can find locally then determine how you will mount this in front of your V1. In my prototype i used fixed aluminum mounts. The ideal are rods which is flexible to different adjustments and other cameras.

The mid format lenses has a longer flange distance which will have you ending up with a longer adapter than a one using 35mm lenses. Try to decide if you can handle this added length to your set up.

Ted

Thanks Ted,
I will search the forum for DIY for this subject.

I see your setup on http://www.tedramasola.9k.com/photo.html
and will try to collect the spareparts.

How to buy (of make) "nikon mount to mamiya lens adapter ??
Cannot find it in internet...

Regards,

Agatha

Agatha,

The mamiya-to-nikon mount is something that i made retrofitting a rear lens cap, adding reinforcement and a pin lock, attaching a canibbalized nikon lens rear mount. Consideration is made to carefully compute the dimensions of this mount to accurately get the flange distance of the mamiya lens via this mount/converter/adapter to the ground glass.

Ted

Bob,

when using mid format lens of the same fov as with 35mm lenses AND maintaining the adapter position, there is 'not much' noticable difference in center sharpness.

BUT edge sharpness is 'better' with the mid formats.

The mamiya mid format lenses produce deeper colors and contrast compared with the nikon and sigma 35 mm.

When the adapter is repositioned for mid format lens use only, the edge to edge sharpness is 'much better' as compared to 35mm lens use position.
Overall resolution is improved.

Ted

Kind Sir Teddy,

I have with me now 2 Mamiya lenses, 45mm and 85mm, and V1 with several raynox :) for V1 and several lens Nikon 80-200, 50mm f1.4, 18-200VR.
And i'm eager to make DIY like yours, and i had push my brother to help me on machining the tools (if needed)

I went through internet today and found these links :
http://www.adorama.com/PRODOFA.html?...pter&item_no=2

Pro Optic 645 DOF adapter, Front lens cover, Rear lens cap, Mamiya 645 lens mount

and also link to the promoter of the product ( kind mr.vargas)
http://www.freewebs.com/wvargas/70mmadapterphotos.htm

and

http://www.fotodiox.com/shop/product...oducts_id=4187

Mamiya lens to nikon mount. (hope the have vice versa)


I know this is DIY forum, but based on your experience, is it better to try the short cut to above pro-optic 645 ???

Thanks for your suggestion,

Agatha

Agatha.

If your friend is not able to make a new complete Nikon to Mamiya adaptor or fashion one out of salvage parts from dimensions provided by Ted, you may find that Les Bosher (in the UK) and other machinists who make lens adaptors already do one.

A "Mamiya-only" groundglass relay device (these also are called adaptors) would be simpler to make than a multi-purpose adaptor which is Ted's most recent evolution. However, if you intend to go the multi-purpose route, Ted's solution should be fine for you.

Your friend will need to take care when making the holes in the casework for the lens mounts and spacers etc.. Step-up rings and threaded spacers are good in that they remain centred but the holes on each side of the box must be accurately centred to parts of a millimetre.

For "normal" and telephoto lenses, this may not be so much of an issue however with rectilinear wide lenses, the diagonal distortion pattern in motion imaging becomes very apparent if it is assymetric due to mismatched centres.

Another small wrinkle is that with some video camcorders, the lens optical centre and centre of sensor do not match. The Sony DSR PD150-PD170/VX2000-VX2100 have this trait and I have been told but cannot verify that the Canon GL1 also does. I don't know if the V1 is offset. Unless you actually test by zooming in on the centre of a test chart, centering the image then zooming back to see if the centre of the chart remains in the image centre, you would likely never know.

This offset if it occurs causes a few small problems in setting centres up if the achromatic dioptre is not to be directly attached to the camera. If you use the camera image of the groundglass image or the image of the front lens mount with the groundglass not fitted, to establish the dioptre image centre by eyematching, although the actual image is correctly centred relative to the lens on front of the adaptor, the achromatic dioptre centre axis and the camcorder optical centre axis become misaligned.

Image sharpness may be inferior and some chromatic abberation may also occur.

To be safe, for the centres, use accurate measuring and marking out onto the job and avoid eyematching through the viewfinder and preferably use Ted's, also the most common method of maintaining optical centre accuracy by using step-up rings threaded into the filter mount of the camcorder to mount the achromatic dioptre if it does not already screw straight in.

Avoid using the threaded filter mount for mechanical support of the groundglass relay device alone but add support with a bridgeplate from the camera tripod mount or bridgeplate and rods. Sooner or later you will add the accessory rods for followfocus and mattebox so may as well integrate it from the beginning.

Some plastic project boxes you might decide to use, may be comprised of a formula which causes latent stresses to reside in the material. When you cut large holes in it, the material may warp and bow inwards. Die-cast metal boxes may also do this.

You may find it necessary to lay up a plate or plywood re-inforcement inside the case to brace the material back to a flat plane. If warping occurs, the lens centres will likely remain accurate however the optical centre axes will become skewed which will throw the projected groundglass image offcentre.

If your friend has a vernier caliper for measuring, to check for parallelism, ignore the faces of the plastic box and measure with the depth-gauge from the front face of the lens mount itself, through the box to the front rim of the achromatic dioptre on front of the camcorder with the camcorder mounted and all bracing or bridgeplates installed.

A more accurate method might be to lay straight edges across both the front of lens mount and rear rim of the achromatic dioptre or step-up ring attached to the case and measure the gap between the straight-edges well outboard of the optical centre axes. This does not enable a final test with camcorder installed but the difference will be negligable.

You could chase the image by eyematching and moving the camcorder end of things about but then the likelyhood is that you will experience an assymetric edge softness.

Finally. The simpler groundglass relay devices or adaptors do not flip the image but present it to the camera upside down. This means you have to flip the image upright afterwards in the editing computer. Some camcorders like the JVC GY-HD250 flip the image upright electronically.

The V1 does not do this. Cineform software if used for capture conversion of footage from .m2t to .avi has a preset which will do this automatically for you. The upside-down image in the viewfinder remains a pest to work with and you may need to add a small LCD monitor which has a built-in flip function or mount it upside-down.

QUOTE:

"It therefore gets a bit confusing because a PL mount lens will go straight on to the universal mount but the backfocus is then way off. The PL mount therefore is actually a PL mount at both ends which adds space to make the flange to focal plane distance correct for PL mount lenses."

END OF QUOTE.


I have been the inadventant purveyor of slight misinformation.

The quote above is from a previous post in this thread above.

My recollection of an event was slightly incorrect. The profile of the PL Mount and the P+S Technik mount is very similar but not identical as I state above.

It is possible to have fitted the PL Mount for a PL lens, then during hasty lens swaps, to have fastened the Nikon or Canon and possibly other other mounts onto the already installed PL Mount in error.

During the event, it was discovered with some concern that the Nikon mount lens simply would not focus after the PL Mount lens was used, - great bokeh though. The PL Mount had become in effect a macro tube. On closer inspection, the fitment is discovered to be not a match but the lens mount will remain re-assuringly firm and does not drop out.

So. Apologies for another firing-from-the-hip error. So soon after another, it looks like it has become habitual.

Agatha.

The fotodiox product would work on Ted's adaptor. You would still need to engineer the added piece which goes in between the camcorder and the groundglass relay device when the Mamiya lenses are used.

Dear Bob,

After read more carefully the process and precision needed for this DIY, i think I cannot find enough resources to do the job. Maybe if later i have a boy friend, i will look someone good in machine-drilling... :)

Anyway, even as simple as : http://www.mediachance.com/dvdlab/dof/index3.htm
I doubt I can make it myself....

So , if i can find this fotodiox, what will be the ready solution for me?
I possible I still want to use these Mamiya 45mm and 80mm lenses along with several nikon mount we have (50mm/1.8, 80-200/f2.8, 18-200/f3.5-5.6)

Letus ?? Brevis.... or PRODOFA (whom claim as the only mamiya lens adapter)..

Thanks in advance... again apologize since this is DIY forum.

Regards

Agatha.

Ted's adaptor is the only one which will make close to the best of both Nikon and Mamiya lens image areas on the groundglass. All other adaptors are either 35mm movie frame size, some 35mm still-image frame size or Mamiya size image only.

Do not buy any adaptors off ebay without checking back with us here first.

I just acquired a nikon 80-200 ED and did some tests with the adapter.

This lens is heavy BUT its really bright and I think I'll be using this often than primes. I also think this will make me leave behind 3 lenses. my 85mm f 2, 105mm f2.8 and 200mm f3.5. the zoom will be very useful in quickly adjusting framing and composition especially in outdoor set ups.

Heres a pic of the lens on the adapter i posted at the JVC forums. its a monster at 31 inches long.
http://www.dvinfo.net/conf/attachmen...1&d=1201610242

Here are some grabs from some test shots today.

Sweet images.

A trace of arc artifact on the chook shot and another. I guess available light was not your friend there. It this observable in the motion footage or does the action or moving images pretty much bury it? The keyboard shot. Is that an old "Beale" or "Cable" brand piano?

You may find running your disk slower, down to 620 rpm or 310 rpm even, and possibly running a 1/100 sec shutter with an extra wider stop of aperture may help bury the arcs. I am assuming you are shooting 24P.

The arc is buried in the motion now unlike the tokina 200mm. Im so curious why the arc shows up in long lenses and not in normal and wide.

I'll try slowing it down.

The piano is a wurlitzer.

My imaging is that the angle of incidence of light from the lens is more closer to ideal for a wider area across the image. Less random scatter so patterns in GG texture might become more apparent.

You may find that a normal to wideangle digital stills lens does it too in adverse lighting conditions. These I understand are optimised for the imagers which share the same problems as groundglasses related to angle of incidence.

The Nikon 12mm -24mm f4 zoom is the worst offender on my setup. I had always attributed this to the f4 aperture but now on having some more thought about it, I am not so sure.

I had the piano tagged as American as it has a sllght backwards tilt to the keys relative to the cabinet work. If ever you are bored and have absolutely nothing to do, lift the top lid and have a look at the writing cast into the frame in centre or possibly right side near the lid.

Mass production piano making apparently shared a a few of the characteristics of our automotive and appliance making of today in that the scale of operation was big enough for specialisation in sub-components like keyboard mechanisms and frames.

So some brands share some parts with others. Like OEMs of today, if enough frames were ordered, apparently you could have your own brand name cast into them.

There you have it, some totally useless information which I gained entirely secondhand and word of mouth.

Hi Bob and Ted,

I have a gift from my relative come from USA, and he will bring me Letus FLIP, and I suppose to use 50mm/f1.4 nikon lens.

Upon your posting here, I'm glad that possible to use my 80-200/f2.8 ED as well.
Will post some footage when available. Maybe I have chances to use his HVX200 and brevis too, when he come to Jakarta this time.

Mean time, we use whatever available in the camera to make DOF-look.
If you don't mind I want to share a footage we took recently :

http://www.youtube.com/watch?v=ZbJz8Qd_vxk

we use in this a handicam panasonic gs320, V1P, several raynox, nikonos u/w cam, d300, d200, 18-200 VR, 50mm/1.4, 80-200/f2.8 , fisheye 10.5 , infrared modified camera, and most of all my DIY stabilizer :P

http://www.youtube.com/user/agathagraselia

Regards,
Agatha

Agatha.


You should enjoy the Letus flip. If you get a Nikon to Mamiya adaptor to fit in the Nikon mount, you should be able to achieve a good look on the Letus which has a large groundglass screen.

The Nikon f1.4 lens you propose to use is a sweet lens for groundglass work.

Have a look at the instructions posted at the Letus website or at the "sticky" on the Letus threads posted here titled Clayton's sticky.

(The word Clayton's in English language is meaning fake or substitute. The word comes from "Clayton's", a brand of party drink which is not alcoholic but tastes the same as the alcholic drink it pretends to be.).

There are some things you need to do to the Letus lens mount to get it working best.

Having a free afternoon I played arround with a Zeiss 6x6 lens and some plumbing equipment.

The GG is an focusing screen of an 1950s Exacta.

Plumbing tube and rubber grommets of the plumbing supply shelf keep everything in place.

In the back sits an Achromat (10 dioptr.)

No glue or other modifications, everything bolts right in.

Took me about 10 minutes including quick and dirty backfocusing.

I just clamped it betwen the HVX and the mattebox.

I can not post attachments here, so check out the pictures and screengrabs here:

http://www.dvxuser.com/V6/showthread.php?t=121773

AGUS35 DPVNE ?? (AGUS35 Deuscher Plumber's Version Non-Erecting.).

Can't see the pics as dvxuser won't let me in.

Your project would have to be good for a Guiness Book of Records entry. The closest I have come to that is a Pringles can, two rolled up socks which had the heels out of them, a handground microscope slide, an X-Fujinon f1.8 50mm prime and a PD150, elastic bands, rolled up pizza box for packing under the Pringles can and a piece of flat pinewood the PD150 was bolted down onto and the Pringles can was banded down onto.

It took me the best part of two hours to cobble together.

I called it the Pringlecam. All that is left are the memories, the piece of wood, the X-Fujinon, four pics up on dvinfo and the PD150.

Bob,

I tested the adapter for green screen work after you said its possible and i was able to pull a good key. Heres some grabs of a raw and a composite. I shot it with a Nikon 50mm at f1.4 and on the fujinon at f8.

I also recalibrated my zoom settings after i realized i can remove the anti flare ring of the fujinon lens allowing me to further plunge the achromat deeper by 8mm.

After these tests i think i can use the rig now without removing the adapter. my only problem now is adding more counterweight on my DIY jib to offset the added load of the adapter.

Ted