Hi Guys

First off...I love the new extreme, it is by far the most professional 35mm adaptor I have used. Feels indestructible. A tank! Build quality a world away from the previous Letus FE and so easy to use. Great picture quality, very little light loss. It really is a winner!

One thing I have seen mention of is a kind of smear with bright lights. I did a few tests today and certainly came across it. The shot without me in it you can clearly see it, the shot with me in it the bright reflected light off the car in the background looks quite odd. It feels like the diffuser gives an oily type smear to bright out of focus highlights...

Have a look.

Phil what cam are you using the Extreme with? (not that it had anything to do with the smear your talking about). I'm trying to put some positive pressure on Quyen to get a move on with a HD100 "Extreme" version. I have the current version of the Letus HD100 and am getting great results but would love a thinner GG and less blooming that comes with the new condenser.

I have it hooked up to my z1 at the moment as it is so heavy it doesn't work well with my JVC 201.

I too would love an extreme version for that, would be a beautiful combination.

I wondered if it was the glass I was using...the shot of me is with a nikon f2 105mm and the other shot is Zeiss 85mm f1.4

What did u mean by oily? It's looks to me like the problem he was having with the other apters, the blooming that was associated with the condenser. It seems like it's that more so than the glass. Where was ur f stop on the 85mm?

Oily is just a way for me to describe it, you know...oily!

Wide open at f1.4

Also curious, have seen photos of Ryan Walters Extreme with the Logo on the front which is white, mine is just etched.

What are other people getting?

Oily is just a way for me to describe it, you know...oily!

Wide open at f1.4

LOL! I think i know what u mean. I notice you have been working with the Brevis. I dont know how that GG is it seems to have no grain at all. My point is I think that what my perception of what you mean by oily is the combo of the grain of the GG and the lense's bokeh, thats my opinion. That's the wasy the Letus HD and all the Letus adapters were are before the new GG again if that's what u mean.

Also curious, have seen photos of Ryan Walters Extreme with the Logo on the front which is white, mine is just etched.

What are other people getting?

Our is also etched, which I like better.

Phil, that is weird. I have tested the Extreme extensively and haven't seen this kind of smear. It doesn't seem to be lens-related because what you are using shouldn't be causing that problem...

I'm a little perplexed because I have shot a lot of stuff in all different circumstances and haven't seen anything like that.

EDIT: Actually what would be interesting would be for you to shoot the same scene with the Brevis or whatever other adapters you have and see if you can replicate it.

I won't be able to replicate it as yesterday was the last sunny day we will see this year in London!

I have used the Brevis extensively over the past year and never had that effect. I had seen frame grabs from other Letus X users with this and I didn't even try and replicate it and straight away it was there.

If half of us are getting smear and the other half is not getting smear what do you think is the problem.

I mean If the lens that you are using with your M2 and Brevis doesn't have this problem. And it does with the Extreme, do you think it due to your lens? Or maybe the Letus Extreme will only work with certain kind of lenses that won't give out smear , glow or ghosting.

Look at Tim Tyler's still shots, he is also having some problems around bright lights.

http://timtyler.net/LetusExtremeStills.zip

The customers wanted more light. Quyen has given them more light.

The customers wanted better resolution, given them that too.

The customers wanted the fixed pattern artifact to go away. It pretty much has.

The means of the achieving those solutions is likely to have been a new groundglass with a finer texture and greater transmissiveness.

The piper to be paid is that beyond a certain point, the finer the grade of the groundglass texture, the more pass-through of aerial image occurs.

It manifests at its worst when the soft background contains bright sharply defined highlights such as white barked tree branches in late afternoon or pinshines off motorcars etc..

Choice of groundglass texture is all a balancing act.

From what I see in Phil Bloom's grabs, sharp highlights are coming through the groundglass.

The downer is choices will have to be made to avoid bright pinpoint highlights in background.

The upside is that footage from this groundglass will intercut much better with direct-to-camera footage.

Lens choices may not make much difference.

I really don`t know if it applies to Letus too but my assumption is that if the SLR lens would be closed down to f4 all that smear should go away and form that nice looking bokeh instead. It loses almost as much light as it would lose with a ruffer GG that will give the same image properties. At least that was concluded after our Cinedof research two years ago. So it really is a balancing act.

T

The customers wanted more light. Quyen has given them more light.

The customers wanted better resolution, given them that too.

The customers wanted the fixed pattern artifact to go away. It pretty much has.

The means of the achieving those solutions is likely to have been a new groundglass with a finer texture and greater transmissiveness.

The piper to be paid is that beyond a certain point, the finer the grade of the groundglass texture, the more pass-through of aerial image occurs.

It manifests at its worst when the soft background contains bright sharply defined highlights such as white barked tree branches in late afternoon or pinshines off motorcars etc..

Choice of groundglass texture is all a balancing act.

From what I see in Phil Bloom's grabs, sharp highlights are coming through the groundglass.

The downer is choices will have to be made to avoid bright pinpoint highlights in background.

The upside is that footage from this groundglass will intercut much better with direct-to-camera footage.

Lens choices may not make much difference.

I really have no problem with it. It really only happens with "extremes", both the flares are from the same object, reflection from the sun on a car and yes both lenses were wide open. I wasn't actually setting out to get this effect, I only noticed it when I got back to final cut pro. If I see it in the future whilst shooting I will stop down a little and lose it! It's a very small price to pay for a quite superb 35mm adaptor. Congratulations to the Le brothers, they have taken criticism for their previous ones and really pulled one out of the bag with this.

It's not quite as bright as the Brevis but then again it's flipped, the difference is tiny.

It's not quite as bright as the Brevis but then again it's flipped, the difference is tiny.

It is not as Bright as the Brevis? I can't wait till Dennis sent you the flip unit. It would interesting to see how they match up . When both adapters offer flip image and one has light smear.

I think the Letus will win out against the Brevis with the flip. Apparently the letus loses just half a stop, very similar to the Brevis CF1. Not sure how much more the Brevis flip loses, I think it is around another half a stop.

I would be very interested to hear if Redrock are planning to catch up with the competition...They haven't touched their M2 in ages whereas the Brevis is constantly being revised and the Le brothers have stuck a big two fingers up to P & S and Movietube with their adaptor.

Now, all they need to do now to make me happy is bring one out for the JVC with a relay. Now that would be one sweet combo.

For aerial image pass-through, tighter apertures are not going to help much except for reducing the actual soft area around the pinpoint so it may be less apparent as an artifact.

You may find you have to use a polariser to dull reflections down a little and maybe do some tricky things with black-stretch in the camera if you have it, to pull down bright highlights and bring up the dark detail to compete for attention in the image.

As a mater of idle interest, try 1/100th sec shutter to see if the groundglass fixed pattern artifact comes back. If you can wring 1/100th sec out of it, this will make a few music video folks who like to shoot a sort of slowmotion quite happy.

...i second that jvc relay...although id prefer it if Dennis came up with one first...

For those who are desperately impatient and already own a Letus for JVC, chances are, and I must emphasise "chances" -- with all the uncertainty, grief and malaffection that comes with uninformed comment (mine) subsequently acted upon by innocent others (you?) with disappointing outcomes ---- got this far ---

okay caveat expressed --- and Quyen, please beat me down to a quivering pulp of bundled neuroses if I am wrong so no harm be done, ----

---- chances are, that the relay for the original Letus35 flip for JVC GY HD100 might be in the meantime usuable from the flip module rearwards with a small mod, on a LETUS Extreme or maybe more easily, on the LETUS economy.

Almost certainly, the bridging tube from the rear of the flip enclosure would have to be carefully drilled with precise screwholes to match the screw fitment of the bridging tube on the Extreme. The internal diameter of the bridging tube might need to be skimmed to match the diameter of the rear shoulder on the Extreme but it may not if the same tube material has been used on both.

Posted by Hien over at LetusDirect regarding the JVC


We are working on that one. Available in couple of months, we know exact what to do already, just finding some good glass for it. It will hook right onto your extreme (Yes, it is modular).

Posted by Hien over at LetusDirect regarding the JVC

Modular...brilliant news. There was me thinking how I can justify coughing up another $1200 or so!

Tell the boys if they need a guinea pig, I AM THAT PIG!

Phil what cam are you using the Extreme with? (not that it had anything to do with the smear your talking about). I'm trying to put some positive pressure on Quyen to get a move on with a HD100 "Extreme" version. I have the current version of the Letus HD100 and am getting great results but would love a thinner GG and less blooming that comes with the new condenser.

Hi Jamon ...I did the same thing but Quyen just answered me " They are working on that" I tried to ask again asking if they have already expecting dates but he never aswered, Do you have another response from Quyen?

Thanks, I guess it would be a good combination....

Hi Jamon ...I did the same thing but Quyen just answered me " They are working on that" I tried to ask again asking if they have already expecting dates but he never aswered, Do you have another response from Quyen?

Thanks, I guess it would be a good combination....

Hey Alan,

I actually Talked to Hein (I hope i spelled his name right) and he said that he was actually playing with one not too long before I talked to him. He said that it was brighter than the stock Fujinon, I don't know if he was just talking but I wont doubt it, I love the Letus. I couldn't nail him down on a date but i will say he hinted before X-Mas so....As you probably gathered from the modular quote they are actually working on a relay that will be sold separately. The relay is probably gonna be around $1,000.

I came across the smear again yesterday. Will post examples. Worst culprit was my f2 nikon 105mm dc. When I used the dc function I could minimise or exagerate it. This could be vital information as to why it is happening.

As a side-effect, does the DC function move the plane of the iris blades forward or backward on the optical centre axis relative to the focal plane?

This might have some bearing on it if it does.

Every adapter will have some effect on the picture, you are shooting thru a diffuser.

M2 has less blooming and very little grain but loses a TON of light and the bokeh has a distinct and sometimes "fake" look, like it was forced in post

Brevis has very little blooming, loses very little light but can get grainy very fast, especially with CF3L. CF1L is a great diffuser but you will need to stack some ND's in front of it to get more DOF.

The Letus EX has almost no light loss but you get the smeary bloomy effect. It is on EVERY unit but it is situational. It is the easiest adapter to use.

Bottom line, know your unit and how to work around its faults. There will never be a unit that addresses all the issues, to fix one, you create another, it is just the nature of shooting thru a diffuser.




ash =o)

Phil what cam are you using the Extreme with? (not that it had anything to do with the smear your talking about). I'm trying to put some positive pressure on Quyen to get a move on with a HD100 "Extreme" version. I have the current version of the Letus HD100 and am getting great results but would love a thinner GG and less blooming that comes with the new condenser.

I'd be up for a HD100 Extreme, should it eventuate.

Sam

The HD100 version of the Extreme will be a modular addon for the existing Extreme. This makes the Extreme very versatile as it can be used now by threading onto a lens or when the HD100 module comes out, it can be attached directly to the JVC body.

I'm trying to put some positive pressure on Quyen to get a move on with a HD100 "Extreme" version.

I already built my own LetUs Extreme for my HD100...work beautifully. And I am not talking about adding the adapter to the end of the fujinon lens. I was able to get a adapter to connect nikon prime to the HD-100 body and then attach the Extreme to it...works like a champ!

EXTREME - NIKON PRIME - JVC

I already built my own LetUs Extreme for my HD100...work beautifully. And I am not talking about adding the adapter to the end of the fujinon lens. I was able to get a adapter to connect nikon prime to the HD-100 body and then attach the Extreme to it...works like a champ!

EXTREME - NIKON PRIME - JVC

Really? I'd like to know more about that...

Les Bosher JVC to Nikon lens adaptor >> Nikon prime lens (35mm or 50mm) >> close-up lens or achromatic dioptre >> the hard bit you make your self - new bridging tube between back of Letus and front of Nikon.

NOTE: This is a theoretical "means", not a verfied and tested "end" result.

The means of the achieving those solutions is likely to have been a new groundglass with a finer texture and greater transmissiveness.

The piper to be paid is that beyond a certain point, the finer the grade of the groundglass texture, the more pass-through of aerial image occurs.

It manifests at its worst when the soft background contains bright sharply defined highlights such as white barked tree branches in late afternoon or pinshines off motorcars etc..

Choice of groundglass texture is all a balancing act.

From what I see in Phil Bloom's grabs, sharp highlights are coming through the groundglass.

The downer is choices will have to be made to avoid bright pinpoint highlights in background.

The upside is that footage from this groundglass will intercut much better with direct-to-camera footage.

Lens choices may not make much difference.


I'm no expert, but shouldn't it be the case that if the camcorder's aperture is wide open, then the aerial image will be out of focus anyway? Perhaps these undiffused pinpoint highlights could be eradicated by opening up the camcorder's aperture and using an ND filter?

I am no optical expert, just someone who sometimes gets a few cogent thoughts together and discovers a particular experiment works.

The use of a wider camcorder aperture makes sense and may account somewhat for the inconsistent manifestation of this artifact and that it is much less apparent in controlled artificial lighting environments. In those, everything is often opened wide to suck in every available skerrick of light which might account for this anomaly.

My personal preference is to try to stay within the camcorder's optical sweet spot in regard to aperture, mainly to stay in the sharpness zone, but also to avoid reported diffraction artifacts attributed to very tight camcorder aperture settings and small format CCDs. Your comment gives me cause to re-examine my preferences.

With the existing LETUS35 direct relay models, this is also somewhat mandatory as the Minolta relay lens sharpness tends to go off when it is fully wide-open. If Quyen is going with a custom relay lens for the new "Extreme" things could get interesting.

I can't speak for the Brevis, SGPro or Redrock M2 as I have not played with them.

The P+S Technik Mini35 direct relay version for JVC HD100, does not seem to care what you do to it. The relay lens is apparently sharp all the way to wide-open, which is likely why you pay premium price for the product.

Aerial image has not passed through in any work that I have observed on it thus far. The same best practice rules apply relating to flare and light levels at the groundglass.

According to P+S Technik's Tino Liberatore, who demonstrated their products here earlier this year, the grade of groundglass they use is as fine as it can be taken without producing passthrough and a lot of work was done in arriving at the ideal grade. (my paraphrase recollection of his discourse).

With alternative adaptors and homebuilds with finer groundglass textures, a long setback arrangement with a lower power dioptre might work better in this regard than a short setback arrangement with higher power as the camcorder's own inherent depth of field will be shallower from being zoomed furthur in or at maximum. This might account for P+S Technik's use of a long arrangement besides the optical benefits relating to edge-to-edge sharpness.

The use of ND filters before the groundglass is consistent with best practice to limit internal reflection and flare in the groundglass in any event.

Minolta relay lens

Pardon my ignorance...but how does a relay lens differs from a regular lens?
I've googled it but I quite don't get it.

When building my own Letus Extreme version for the HD100 i had copied the idea by looking at a picture of the current Letus version for the HD100. I saw there was a lens attached to the camera body and that was in turn attached to the Letus. After searching for the perfect lens...i found a nikon that would allow me to focus on the Letus Extreme. The picture is perfect and sharp...still i dont understand the concept of the Relay Lens.

In basic terms, it doesn't. All you are doing with relay is taking a picture of another picture. However there are desirable minimum performances required from it.

The term "relay" is applied to the optics which lie between the groundglass in the case of a 35mm adaptor or the display tube in night vision.

In "lens-in-camera" style video cameras, the "relay" lens becomes the combination of the camcorder's inbuilt lens and (if neccessary), the close-up lens which goes on front to enable closer focus.

In detachable lens style cameras the "relay" lens may be a dedicated lens to replace the standard lens and good for nothing else than close focus, perfect image without barrel or pincushion distortion and preferably equal sharpness throughout its aperture range. If an adaptor builder chooses to use the existing standard camcorder lens plus a close-up lens on front, this combination becomes the "relay".

Ideally, a dedicated lens will also be small to avoid the combination of camcorder and adaptor becoming too unwieldy.

SLR camera lenses in the range approx 35mm to 50mm can be used to "relay" the image from the groundglass to a detachable lens style camcorder imager. Most will require an added close-up lens on front or forward offset to enable "macro" focus, so there is little advantage to this approach except for cost.

The LETUS35 uses a 50mm Minolta SLR camera lens. P+S Technik use a dedicated lens which previous references here suggest is made for them by Schneider-Kreuznach.

For home builders, the 55mm f3.5 Micro-Nikkor might work for them without any close-up lens on front straight off the Les Bosher adaptor or may require a minimal forward offset.

The low light performance would be less than ideal.

Off-topic, the Micro-Nikkor f3.5 55mm apparently was used in microlithography for scaling of the microprocessor designs from human workable drawing sizes down to the real-world size of the chips in the early days of R&D, another reference from this site.

In basic terms, it doesn't. All you are doing with relay is taking a picture of another picture. However there are desirable minimum performances required from it.

The term "relay" is applied to the optics which lie between the groundglass in the case of a 35mm adaptor or the display tube in night vision.

In "lens-in-camera" style video cameras, the "relay" lens becomes the combination of the camcorder's inbuilt lens and (if neccessary), the close-up lens which goes on front to enable closer focus.

In detachable lens style cameras the "relay" lens may be a dedicated lens to replace the standard lens and good for nothing else than close focus, perfect image without barrel or pincushion distortion and preferably equal sharpness throughout its aperture range. If an adaptor builder chooses to use the existing standard camcorder lens plus a close-up lens on front, this combination becomes the "relay".

Ideally, a dedicated lens will also be small to avoid the combination of camcorder and adaptor becoming too unwieldy.

SLR camera lenses in the range approx 35mm to 50mm can be used to "relay" the image from the groundglass to a detachable lens style camcorder imager. Most will require an added close-up lens on front or forward offset to enable "macro" focus, so there is little advantage to this approach except for cost.

The LETUS35 uses a 50mm Minolta SLR camera lens. P+S Technik use a dedicated lens which previous references here suggest is made for them by Schneider-Kreuznach.

For home builders, the 55mm f3.5 Micro-Nikkor might work for them without any close-up lens on front straight off the Les Bosher adaptor or may require a minimal forward offset.

The low light performance would be less than ideal.

Off-topic, the Micro-Nikkor f3.5 55mm apparently was used in microlithography for scaling of the microprocessor designs from human workable drawing sizes down to the real-world size of the chips in the early days of R&D, another reference from this site.

thanks for the response...you da man. Upon close inspection, my lens in between the letus extreme and the JVC is a Nikon with Macro..I remeber that all other lenses I tried did not work. All that extra telephoto that I was getting, did not allow me to properly focus on the ground glass...go figure

Coco.

If you have a chance, could you shoot a test chart and post a frame grab, also provide the model of Nikon lens. This would be a good help for home-builders seeking direct relay to the JVC HD100 style and Canon XL style camcorder families.

If this approach is viable, the stills lens vendors and ebay may become confounded by another sudden demand for a particular lens type.

Coco.

If you have a chance, could you shoot a test chart and post a frame grab, also provide the model of Nikon lens. This would be a good help for home-builders seeking direct relay to the JVC HD100 style and Canon XL style camcorder families.

If this approach is viable, the stills lens vendors and ebay may become confounded by another sudden demand for a particular lens type.

I will gladly do it....but....where do i download a test chart. Do i have to use certain lights, wattage, what distance from the chart should I shoot. Any paramaters I should keep in mind? Any type of lens in front of the LetUs Extreme?

Coco.


A few of us here have used the EIA 1959 chart.

Here is a web address which gives some info on charts. It linked to a high quality copy of the EIA 1959 chart which can be downloaded as a .pdf and printed.

http://www.bealecorner.com/trv900/respat/

Use the standard 50mm lens. The chart should frame vertically at about 1M to 1.2M, which is about 39" to about 47" approximately. There will be a missing piece on the sides because this chart is a 4:3 chart.

Whatever light you can put on it which does not force you into more than about 3db video gain should be okay. Position the lights in traditional key-fill or crosskeys so that no shine comes back off the chart. Otherwise take it outside and clothespeg it to a chairback.

Try to make sure it is square-on to the camera lens otherwise there will be soft areas.

Phil, just curious, when you shot the initial footage that revealed the smear, did you have the camera iris closed tightly, or did you stop down with an internal ND filter? Check this thread out here, and give me your thoughts.

http://www.dvinfo.net/conf/showthread.php?t=112518&page=2

Being a soon to be Letus owner, I'm following this with great interest!

I already built my own LetUs Extreme for my HD100...work beautifully. And I am not talking about adding the adapter to the end of the fujinon lens. I was able to get a adapter to connect nikon prime to the HD-100 body and then attach the Extreme to it...works like a champ!

EXTREME - NIKON PRIME - JVC



which adapter are you using to mount the nikon lens to the jvc body ?

which nikon prime lens work the best ?

any magnification issue ?

do you have any footage to post ?

thanks

Phil, just curious, when you shot the initial footage that revealed the smear, did you have the camera iris closed tightly, or did you stop down with an internal ND filter? Check this thread out here, and give me your thoughts.

http://www.dvinfo.net/conf/showthread.php?t=112518&page=2

Being a soon to be Letus owner, I'm following this with great interest!

can't remember. But not experienced it since