Preface:
I think this warrants a new thread, although there is another similar one right here: http://www.dvinfo.net/conf/showthread.php?t=49790
I think this review would of been lost in that thread as it already was going off in other directions.
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What is LetUs35? (http://adapterplace.com)

A device, that when attached to a video camera together with a photographic lens achieves a MUCH shallower Depth Of Field, as seen in many professional productions, and normally only obtainable with more expensive, larger professional equipment. It is a low cost piece of equipment that "simulates" expensive equipment by achieving a similar look with a less expensive camera.

Equipment used in testing:
- LetUs35 (black anodized, 72mm thread, FD mount) from adapterplace.com
- Canon 50mm f1.2 FD lens
- Canon 28mm f2.8 FD lens
- Panasonic DVX-100AE camcorder (PAL)
- Sony DCR-PC120E camcorder (PAL)
- VEGAS 6 (for capture and flipping of image)

Cost of LetUs35: $300 retail ($180 as special deal sometimes available, i.e. beta testing, or eBay)

Competition to LetUs35 (from $$$ to $):
- Mini35 (pstechnik.de), note: about $9000
- Cine-One (cine-one.com/de/), note: incl. CineOne/Indi
- G35 (Guerilla35.com), note: not available as of this writing, but about $1000
- Micro35 (redrockmicro.com)
- Marla (marlathemovie.com), note: DIY
- DOF Machine, (mediachance.com/dvdlab/dof/index.htm), note: DIY

LetUs35's cost is the lowest of the ready-made units. Only cheaper option is to make one yourself, and I'm actually not quite sure if it can be done cheaper, especially if you calculate your hourly time spent building a unit at more than $1.50/hour! ;-)


Review:
I have read numerous reviews of various Depth Of Field (DOF) devices. They seem to have the following features (or maybe 'problems') in common, although to varying degree:
- they reduce the contrast
- they soften the image somewhat
- they introduce "grain"
- any dirt, dust or particular matter within the adapter will be VERY visible in the final video
- they 'lose' light

I first tested the LetUs35 with a DVX-100AE (and the Canon FD 50mm f1.2 lens), set to SQEEZE mode, and directly coupled to the DVX's front via the 72mm thread. An email to Quyen Le (of adapterplace.com, maker of LetUs35) helped me through some small issue with adjusting the LetUs35 so that it lines up correctly once threaded all the way. Email response was quick.
Once the LetUs35 is attached to the DVX-100AE, one has to zoom in just enough to view the full image, and set the manual focus correctly (reading on DVX was MF13).

The unit comes with an external battery pack which holds two AA (UM3) 1.5V batteries. I used NiMH as recommended by adapterplace.com. This battery pack has a switch which turns on a small vibratory motor which removes most of the very visible grain. I have already made suggestions to possibly integrate a rechargeable battery inside the aluminum housing, with a DC connection to charge that battery up. It would "streamline" the LetUs35 much more.



The cam's LCD will show the image up-side-down, which is nearly impossible to get used to. There are, however, tricks that can make the LCD show correctly, such as a magnet, or depending on the cam, a simple menu setting. (Note: I have not bothered for this test to figure out how to do this on both cams I tested it with.)

Now on to shooting:
Just looking at the LCD is VERY IMPRESSIVE, as one can immediately see the effect of shallow DOF. It is an amazingly useful tool, such as when a particular object or subject needs attention drawn to it. You can focus on one thing, and have everything else blurred out.

Results:
But the resulting video that I took with the DVX-100AE weren't quite as impressive as I'd hoped for, once I reviewed them on a broadcast video monitor. The images seemed washed out, not detailed, and losing much of the 'resolution'. DOF was awesome though of course.

BUT:

When tested with the DCR-PC120E, all the negative points I found in the DVX completely turned around:
Since the DCR-PC120E is quite harsh by itself, the introduction of the grain, smoothness/softness, etc, made the final image from the DCR-PC120E MUCH more pleasing than would of been possible without the LetUs35.

So, I can summarize like this:
The introduction of MORE grain, softness, etc. on the DVX proved –for me at least– to be too much. I also read that Barry G. had similar experiences when testing a G35 with a DVX. It's like having a film look applied to footage that already HAS a film look. The one positive thing is of course the addition of the shallow DOF, but it comes at a hefty price: picture quality. I guess since the DVX is so good at that all by itself, the DOF device really has to be MINIMALLY 'intrusive' on the DVX's image in all other aspects other than DOF. It really only needs to add shallow DOF, not alter the image look.
The LetUs35 just might not be able to do that alone.

B U T:
with the DCR-PC120E (and probably with most smaller cams also, maybe up to a GL1/GL2/VX2000) the LetUs35 VERY MUCH improves the look and feel in ADDITION to adding the shallow DOF.
It's almost like taking a $1000 camera, and making it into a DVX type cam, by giving it a film look, AND adding shallow DOF (I did write ALMOST! ;-). The added grain (even if only in a small amount) adds to the DCR-PC120E look, and it's fun to shoot with (although the LetUs35 is almost as big as the DCR-PC120E, so I'd have to think of how to properly attach it, as it's too much weight on the little 37mm thread of the cam)

So: the LetUs35 is a GREAT, low cost alternative to the higher end offerings. Ideally suited for probably the consumer grade cams though, IMHO. The DVX and probably also the XL-2 with their "built-in" film look, suffer too much from the added artifacts, IMO, especially as shallow DOF can be done to some degree with other little tricks without an adapter. For a DOF device to work very well with the DVX, it has to be nearly grain free and not change the image in any other way either: no or hardly no introduction of softness, no or hardly no loss of contrast, etc.
We'll have to see if the G35 can deliver in this regard (seems to cope well according to some sample clips), although like I mentioned, it is more than three times more expensive.

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The LetUs35 can turn an inexpensive camcorder into a film look camcorder with awesomely shallow DOF for under $350 (including a secondhand lens, adapter rings and shipping)
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(Notes: I didn't do extensive tests in trying to change the scene file settings with the DVX although I' sure I could of improved the picture quality somewhat.) Also: between the time when I tested the DVX and the DCR-PC100 the weather had completely changed from sunny to rainy, so I could not perform realistic and helpful side-by-side comparisons. But I will upload some screen captures soon.)

P.S.: I believe Quyen is already working on an "HD" version.


Reviewed 17 September 2005

Marius,

Thanks. The Letus35HD version will be available soon, thanks.

Quyen

If you put the detail up and put cine-matrix to NORM you'll probably loose a lot of the grain that the dvx naturally has, while keeping the gamma to cine-like. That's what I am planning on doing when I get my Letus35.

Whoever received the 72mm macro on the Letus35 unit will probably experience the same problem of softness toward the edge. The problem is, the 72mm macro is too large and the outer part of the macro lens will add softness to the video. There is a way to overcome this problem. Get a black cardboard or thick paper and cut it to a size of the macro lens, cut out the rectangle piece in the center of the cardboard to the size of about 24x36mm and put it between the camera lens and macro lens. This will increase the sharpness of the outer edge. If you see the edge of the cardboard on video, cut it a little more. I receive no report from people using 58mm macro lens on this problem so far. For people using 58mm macro, I think this method will also increase video sharpness. If you find this method is helpful, please say something so we all can learn, thanks.

Quyen

Thanks Quyen,
I tried that yesterday after your email, and it did improve the sharpness.

Now I have a question though: is a 58mm macro sharper than a 72mm one with special cardboard?

Marius,

The sharpness of the image mostly depend on the size of the macro being used. When you use the 72mm macro then use cardboard to block the outside, it will give you the smaller opening and give you better sharpness. This is the reason why the DCR-PC120E can give you better image than the DVX100AE when using the Letus35. The 58mm is smaller in size and will give better image than the 72mm but not better than the 72mm with cardboard if they both have the same quality. When using the macro which is too large, the outside part will do more damage than good to the picture quality. I hope this will answer your questions. Thanks.

Quyen

I hope this will answer your questions.

It does. Many thanks Quyen,
and kudos for a fantastic product!

Sample movie uploaded (8mb, QuickTime Sorenson3):


Shot with DVX-100AE and LetUs35, and Canon 28mm, f2.8 lens:

http://erkljhtnoiwv3y48tvybw38ilyt9obvw3y4ivusher5ktghv2798y5viehtiytv.us/letus35-sor3.mov

There seems to be an awful lot of color abberation in the trees, doesn't it?
It also seemed to be there with the movie Ben has made (in some shots and not as obvious because it was posted in a smaller format).

But here it is very clear. Mmm. Makes me wonder. Is this because of the design?

A cut off arm is very scary. Not as much as abberation. Did you ever try shooting a contrasty black and with object, like a checkerboard pattern?

What were your scene file settings for this? And was this shot before or after you fixed the problem? This looks really nice but could be zoomed in a bit more and focused if possible. Describe what you did to get this shot.

Sharpness doesn't look very good.

Marius,

Thanks. The Letus35HD version will be available soon, thanks.

Quyen


What will the difference be? P+S doesn't have a special adapter for HD for example. Because it shouldn't matter. What matters is the lenses you use with the adapter. Your shooting lens and macro lens is what dictates how sharp your image will be. So, it would be interesting to know what will be the difference in the Letus35HD. Are you just using a better quality Macro? Finer GG for less grain? What is it?

What were your scene file settings for this? And was this shot before or after you fixed the problem? This looks really nice but could be zoomed in a bit more and focused if possible. Describe what you did to get this shot.

Scene file was F5, slightly modified, but still 25p.
This sample DID include the carboard modification.
Unfortunately I did this by myself, and in a hurry, as what would of helped even this silly thing, would of been an immediate rack focus to the arm.

Sharpness doesn't look very good.

Aye; two things to consider also:
1) EVERY time you add glass/lenses/filters in front of the naked cam's lens, you're going to loose sharpness. The degree will vary. ALL these DOF devices lose sharpness, some more than others.
2) Since we now have an EXTRAORDINARY SHALLOW DOF, any 3D object will only have one small "plane" in focus. With some lenses and in some conditions this can be not much more than 1/2" (12.7mm) wide. In this example, I'd say that only about 1" or 2.54cm are in focus.

Michael Maier

Every optical element has its property. For example, same 1/3 inch lens but one is good for DV and other is optimized for HD. Since the Letus35 basic is built on affordable strategy, it uses affordable parts to deliver low cost adapter. With 58mm macro lens that we use, the VX2000 works good. However, HD is more strict than DV with sharpness. Therefore, we have to use better optical element to deliver a better solution for HD. Of course, price will be different. With the mini35, they build their equipment for the price that I and many other can't afford. How dare they uses affordable parts to build their equipment? Thanks for asking.

Quyen

Thanks. But as I said, what could you replace besides the macro? The GG doesn't really affects sharpness as it does grain. It's just a projection screen. The camera doesn't see through it. So it doesn't affect sharpness. You can maybe improve on the building quality of the adapter. But besides the macro, I don't see how you can improve anything else optically.
How much will the HD version cost by the way? At least approximately?

I don't think you know the complexity of buiding the unit. It involves many factors than just good optical glass. I am still collecting data from beta testers, it's too soon to tell what need to be replaced. I am sure not just the macro lens. The price would be in the neighborhood of $400-$500. Still affordable. We will post the final price when it's ready to be shipped, thanks.

Quyen

Well, the principle of all these adapters is pretty simple really. If you get a SLR camera and use a camcorder to focus in the SLR's viewfinder, you will get the results of the shallow DOF. There's really no complexity in suck adapter. Specially the el cheapo ones with the upside down image. The P+S is more complex because it has a relay lens and flips the image back to the upright position. But these low budget units are basically a tube with a lens mount in one end, a GG in the middle and a macro lens in the other end. All you need to do is to calculate the right distances between them. So, there isn't really any complexity. I still can't see how you could have a HD adapter , rather than having a better built and or better quality one. You can maybe get the GG to move faster(since there seems to be a problem with this issue and your adapter) to eliminate grain and pattern, and you can get a better quality macro. But optically, there isn't really much more you can do. I think the reason the Letus35 seems to look so soft, may be a low quality macro. It’s a pity really. Because it seems to have great potential.

Another important element in the adpater is the condensor lens. In my opinion the adapter is useless without it. I know Quyen has done ALOT of research on all this. I tried building Quyens design a while back when he made a tutorial of his design, mine did not work. Quyens design is extremely elegant, and he has done alot of work to put it together into a working version. Believe me, its not just a simple matter of putting it together. Yes the concept is very simple on all these adapters, but getting it to useable quality, especially for HD, thats the challenge. It is possible though, and thats where the complexity, and research comes in.

Just my 2 cents,
Wayne.

I still can't see how you could have a HD adapter...

Hello Michael,
you seem a little bitter about all these adapters and stuff, as you seem to be a little argumentative on this subject?

Quyen has made an affordable adapter. He is taking suggestions of persons who have one of his units, and is trying to improve on the design. It's that simple.
Not everyone will like this, or any other product. That's fine.

Cheers though, and happy filming,
Marius

You either need a macro or a condenser right? I don't think you need both.

Michael,
The Macro and condensor lenses play 2 different roles in these adapters, a commen misunderstanding. The condensor lens is used to get rid of vignetting. The macro lens is to help the camcorder focus in the small image area of 36x24mm. Both mine and Quyens designs use condensor lenses.

Wayne.

A condensor and a macro(achromat)?

Michael.
Yes thats right. Quyen's adapter uses both. They play 2 different roles in the adpater. Its not until you start researching focal lenghs and diameters for condensor lenses, best GG grit size, correct distances, what strength macro to use, best mechanism to move the GG, building that mechanism effectively and strongly as not to produce to much noise, but be strong....etc

So many variables of each element, finding the correct combination, and making it compatible with a wide variaty of camcorders, is the complexity.

Thanks,
Wayne.

So macro and condensor? No wonder it lowers the sharpness so much. In this case one shouldn't go for anything else but the best macro and condenser possible. The Mini35 doesn't use a condenser and macro, does it?
Anyway, I was talking about having a HD version, which would require anything else than optical improvement, which is basically a better macro and condensor. It would probably be the same adapter with just better optics. It's not like a whole new R&D and a new adapter needs to be developed. That was my point.

Yes point taken, not too much more effort to create HD from a standard SD unit. But i think its also the GG and the moving mechanism that comes into play here. A HD unit is going to be less forgiving to any kind of artifact an adapter produces, so any grain movement not noticable on an SD cam maybe apparent in HD? In terms of sharpness, yes its mainly the macro and condensor, but I think more research into ground glass grit size and its effect on sharpness and if it has any effect needs to be done, probably what Quyen is doing right now.

Thanks,
Wayne.