The (Unofficial) Home Theater Brothers Lens Thread

Hey Buck,

Excellent timing for this thread. I anticipate the purchase of the HD or HD+ in the near future. Could you also outline the differences/benefits between the two?

Thanks in advance for the help.

Bob

Buck

Post a few Pics of your setup once you have a review for us

Buck,
Please tell us about the quality of the lens and your setup. Can you compare it to other lenses?
thanks,
Jeff

Buck

Wheres are update

ditto

Hey buck, I live in cottage grove, mn and I am also leaning towards getting the improved anamorphic lens from home theatre brothers. I am going to pair it with the benqw9000, so I hope your results are positive. Hope to check back here soon and see.

Wow, I'm from Hastings, small world. I honestly have nothing to add to this topic really, other than I've been looking at CIH for a while but the lens' are always too spendy for my blood. Cheers!

Ok folks! I've got my HTB Lens all set up and I'm ready to review this puppy! Is this the proper thread? Are there any rules about posting photos that I should be aware of? Anyone interested?

Of course! Please post up a review. I'm very interested in it and I'm sure there are a bunch of others interested as well!

Be sure to do some tests for chromatic aberations at the edges of the screen. The only thing I can think about posting pictures is to post a lot of them. Oh and use a tripod and a timer so the camera is steady.

I saw one of these lenses at cedia. Please let me know what you see in the following areas
1 - loss of contrast when the lense is in place
2 - extent of chromatic aberation at the edges of the picture
3 - how much pincusion

The one that I saw wasn't setup optimally. I looked to me like it did exactly what it was supposed to. It delivered a pretty crisp 2.35 image! The comparison would be to the panamorph (about $3k) that really does produce an exceptional image.

I really would like to see a test pattern that shows resolution at screen center and at screen edges.

I wont have my lens until next weekend
Z

So where are the reviews?

For those of you interested in the Home Theater Brother's (HTB) anamorphic lens, I'd like to offer my recent experience. I purchased my HTB lens almost a couple of weeks ago now and have had a chance to really get to know it's strengths and weaknesses.

I purchased my HTB lens from Randy using his web site's posted email. Since the moment that I contacted him, his communication and professionalism has been top notch. Perhaps it's because HTB is a small outfit, but I really feel like I've been given one on one attention throughout the entire purchase.

I spent the extra money and bought the Anti Reflective version of his lens. It's said to have better light transmission qualities and at the price point that we're talking, I figured an extra 20% was well worth the extra quality.

Randy packaged up the lens with plenty of peanuts and shipped it out to me on the same day I ordered it. It arrived very quickly and after I pulled it out and gave it a good once over, it basically sat on a shelf waiting for my brand new RS1 to arrive.

In the meantime, I inspected the quality of the lens. HTB has created an extremely solid metal housing that, while simple, is elegant and functional in design. The design essentially sandwiches the dual AR prisms between the top and bottom case plates. A dense, but very thin foam lines the top and bottom of the case and works extremely well to keep those lens in their "factory set" positions. I consider the build quality to be excellent. I think I could drop this baby on my carpeted home theater room without any damage. (But I'm not going to test that theory!)

Besides being sturdy, the lens and associated casing is surprisingly heavy, so I wanted to be sure and create a mounting system that could handle the weight and still be flexible.

The prisms themselves are magic to me. IE, I understand the theory of prisms and an anamorphic horizontal stretch lens quite well, but I can't really speak to the quality of the lenses themselves. I'll have to let the resulting picture quality speak for itself in that regards.

Once my RS1 arrived and was placed in it's RPA 184 mount, I was ready to mount the lens. Of course, I held it up in place to see what would happen and sure enough, it looked like it was going to work just fine.

To aid in mounting, the HTB lens comes with an adjustable mount that is connected to the lens via two thumb screws. Into each side of the mount is built a special threaded insert that is designed to accept the thumb screws. These mounts allow the lens to point up and down, handling the needed adjustment to the Y axis. To handle any panning and tilting, you'll have to come up with your own method.

While driving to Home Depot, it dawned on me that I could implement an extremely low tech and flexible mount system out of threaded pipe. I was going to build a sliding unit, but after I had this mini brainstorm, I just had to try it. It cost less than ten dollars and took about ten minutes to put together. The most difficult part was finding the ceiling joists to which I firmly screwed a mounting plate to.

The photos below show my ten dollar mounting system. Everything is firmly hand tightened, except the top most thread which is tightened enough to allow the unit to rotate, but not so little as to let the mount swing out of control. This allows the entire system to be tweaked tremendously, tightened, and then rotated out of the way and toward the back of the projector. Randy thought it was cool when I sent photos to him. There's zero slop as well, meaning that once I 'dial' the mount in, it doesn't move on me. (Yeah, I need to paint that peice of plywood black!)

Next I'll cover adjustments and image qualities. Yes, I know, you wish I had started with that! Patience, grasshopper!

After mounting my HTB lens in a way that enabled me to tweak to my heart's content, I started to throw images up on the wall.

Having never used such a lens, I was surprised to find that some of the adjustments were counter intuitive. IE, if you want the image thrown a bit to the left, you have to point the lens a bit to the right. Clearly there are "sweet spots" in regards to the optics involved, and getting your lens to work well with your projector and screen will require anywhere from a few minutes to a half-hour to get right. My advice to anyone purchasing such a system is to ensure that their mounting system is easily adjusted.

I took Randy's advice and put my RS1's lens as close to the HTB lens as possible. I haven't found any stray reflections coming from the front or back of the lens. Nothing is projected up on the ceiling, etc. HTB supplies a little black foam cut-out to help prevent unwanted "back into the project's lens" reflections, but I haven't found the need to use it. Presumably this is because of how close I can match up my RS1's lens to the HTB lens.

For test purposes, I used a combination of image sources. Because the RS1 won't natively vertically stretch hi-def signals, I was really limited to stretching standard def DVDs. I picked Star Wars and The Fellowship Of the Ring as test DVDs because, well, duh, who wouldn't!?! In addition, I downloaded a 720p version of an anamorphic test screen, the results of which are shown below.

Twisting, panning and tilting the lens all change the optical nature of the projected image. Tilting the lens will cause pincushing; anywhere from barely noticiable to extreme. Finding a sweet spot is quite easy and once you've done this, the two thumb screws can be tightened. Twisting the lens shouldn't be necessary unless you mount isn't straight. Panning the lens is required to ensure that when you put the lens in it's final position, the resulting cinemascope image is centered on the same location the 16:9 widescreen image is centered. I originally missed this and was a bit annoyed that I had to manually use horizontal lens shift to correct for it. Learn from me and don't make this mistake. Once you have the HTB lens in it's proper position, it will expand the projected image centered exactly as it should.

In the following photos, you'll see the projected anamorphic test image projected with and without the HTB lens in place. I have a black velvet frame, and you may notice a bit of cropping occuring... don't sweat that. Of course, the image also looks better than these photographs can show.

These two images are to tide you over. In my next post I'll write up on the strengths and weaknesses of the lens (in my opinion), any optical abberations I'm seeing, and I'll touch on why in my unique case, I may not end up using it! (How's that for a teaser?)

Looking forward to the next update. I'd like to see a high resolution shot of a scene with high contrast (some sort of black to white transition) near the edges of the screen so we can see what the color fringing looks like.

Thanks for the info!

Focus looks WAY out on the left. Unless it's your camera?

Let's get to the meat! I'm going to break this down into "effect" and "affect".
First, let me speak a bit about the "affect".

I sat my wife down and said, "Ok, are you ready for this?". She was patient with me.

First I hit the magic stretch button on the RS1 and the 16:9 image filled the screen. I considered discussing the merits of lighting up all the pixels on my panel, but decided there was a better time for that.

Then, I walked over to the projector and rotated my lens into place. My wife actually said, "Wow!". I later thanked her for saying "Wow". The affect was quite dramatic as we watched the opening vision of Frodo's home town fill up a 111 inch wide screen. It was glorious and we sat there enjoying the view for several minutes. Of course, I was looking at the edges of the screen; scanning for signs of reflections and other curses of the optical gods. I couldn't detect any problems... but I was watching a movie, not critically inspecting a test image. My wife then said to me, "When are you going to fill up the entire wall?" I think she was serious.

So, the affect of the lens is exactly what you would hope: It wonderfullly stretches the image as it should and gives you a theater experience. Allow me to say it in as clear terms as possible: At the price I paid, this is the best home theater deal I've gotten in a long, long time. When compared to the prices of the "big boy's" lenses, this clearly falls into the "great bang for the buck" category.

Now, let's talk about the "effect". As fun as the lens is, it's not perfect. As mentioned earlier, if not carefully adjusted, you will get some pincushing that can be from minor to severe. To me, the pincushing is a total non-issue and well under control. I'm projecting from 14 feet back onto a (final size) 111 inch wide 1:2.36 screen. I think in my case, it's minimizing pincushing.

Timmy (above) mentions "color fringing". This is a term I'm not familiar with, but I'm guessing that I'm seeing it. The greatest optical downside is that as the image moves away from the center of the screen, the lens suffers from a linear increase in horizontal blue shift. IE, the higher frequencies of light are being expanded more than the lower frequencies. These mini rainbows are clearly visible when you walk up to a static test image (or take a high resolution photo of a still image), however, I never noticed it until I did this.

In the pictures below, you will see a worse case situation. Here I have the white lines of the anamorphic test image being drawn next to their black background. I purposely took these photos on the far left side of the image. (The right side of the image has a mirror effect.) You can clearly see the effect in these shots.

Let me reiterate my last paragraphs: I'm purposely highlighting the very worse effect that I could produce with a "close to properly" set up lens. In use with a movie, I would not have noticed this issue at all. I feel so strongly about this, that it pains me to even mention what I'm seeing... particularly without first consulting 'The Brothers' themselves. Yet, it's there and I feel needs to be mentioned.

As I'm typing this, I'm seeing a comment saying that the focus looks way out on the left. I believe that you're seeing the effects that the shots below will highlight. With tweaking, what you're seeing CAN be minimized. IE, at one point, I had the left side looking better, but at the cost of more problems on the right side. I have no doubt that I can make the image look better with a bit more tweaking... so with that said, I'll post this and finish up in a little while with some large Star Wars shots and my final take on why it might not be the right solution for me. (What, more teasers?)

Yes VTPete, what you described is the color fringing (or chromatic aberrations) that are caused by the two prism setup.

It's going to be there no matter what and with tweaking the best you can do is average it out to the left and right sides so it's not too drastic at any one point. Not a deal breaker but something to be aware of.

Could you try to get a shot from a movie where this is present? It's tuff to picture how much it would effect a movie image just from the test patters.

Thanks for all the work!

If the chromatic aberation is what's causing that L/R out of focus condition in your shot, then it is extreme. It looks out of focus as well. You might try changing the PJ's focus and see if you can "improve" the L/R focus. The chromatic aberation won't go away if it's there, but the individual colors will come into focus (better). That would speak to whether or not the focus at the sides in "right". The PJ's optics and photos can add to the issue.

The pixel size limitations on posted forum images would require me to resize my photos to a point where I don't feel they are properly showing what the image quality is like.

As such, I'm going to refrain from posting movie images.

All right, all right, I'll post ONE, but guys, please don't complain about the image quality of this snapshot as a) it's not representative of the true picture and b) it was taken before I had finally tweaked the lens.

So, consider this a shot to put you into the proper mindset of what it's like to use CIH.

-Pete

P.S. If you look carefully, you'll see the black foam core edges that I used to blacken the ceiling. Darkening my room from at least the projector forward was the best thing I could have ever done.

Throw some high res shots up on a free image hoster like ImageShack:
http://imageshack.us/

And just give us the link.

Cheers!

Summary:

As DarthBuck has pointed out previously, the HTB lens buying experience was personal, professional and informative. I hope that as HTB grows Randy can continue the kind of support that he showed me with all of his customers.

What do you get with this lens? In my opinion, you hit the sweet spot between price and performance. Are more expensive lens going to perform better? I'm not even going to answer that because the goal of the HTB lens is to get CIH into the hands of the masses, and that it does wonderfully.

Pros:
a) The lens is solidly and professionally built.
b) It uses two high quality lenses with anti-reflective coatings that really work.
c) Set-up is a breeze.
d) The price was right.
e) The optics do the job they're supposed to!
f) My wife said, "Wow!" (Put a price tag on that, guys!!!)

Cons:
a) Getting the lens into the perfect position takes patience and a bit of trial and error.
b) There's definitely some CA occurring. Seems like this is a known issue with two prism systems.

Now, with all of that said above, you may be wondering why I've been hinting at why this lens might not be right for me. It's because while I was testing this lens, I kept manually zooming out my RS1 to fill the screen for comparison shots.

When I would do this, I was amazed at the quality of the resulting image. My screen is black above and below for several feet, meaning those pesky black bars are not visible. (And we all know about the RS1's blacks.) Also, the brightness was, for all intents and purposes, equal with the CIH / Lens method. I've scratched my head over this for several days and the only explanation that I can offer is that the RS1's light efficiency is much greater at wide zoom settings. Because my projector is a reasonably long distance (14 feet) from the screen, I'm guessing that I'm not able to make full use of the full lumen output of the projector. When I zoom out to fill my 1:2.36 screen, I lose light from it being spread out, but I gain some from the efficency of using the wide zoom mode.

The result is that I'm not seeing (and neither is the camera) a benefit to using the HTB lens with this setup.

Additionally, the RS1 lacks a vertical stretch for hidef signals, and despite earlier rumors, JVC probably won't add one. And, I'm not about to go spend a couple of grand for a scaler that handles HDMI, 1080p and 24 frames per second... not when I can zoom out and still be blown away by the image quality.

So, I'm in no hurry to make any final decisions. I've spent 15 hours playing with my RS1 and still have not sat through a full-length blu ray movie. I think it's about time I do so!

In summary, I'm going to congratulate the HTB team for building a great product. I know that there are other options available, but I could only buy one and I'm happy that I did. Randy is a great guy to work with, and if you're considering purchasing a lens, give him a ring and discuss it with him. Although we didn't discuss return policies, my guess is that if you buy the lens and you're not happy with it, you'd be able to return it. So, what do you have to lose?

-Pete

P.S. If there is sufficient interest in this thread, I could be persuaded to take and post more pictures. I hope this has been helpful.

VTPete, there's interest in some more shots. Especially if you could get them uploaded at a high resolution to a sight like ImageShack.

A couple comparison shots between the lens in place and using the zoom method would be great!

Cheers.

VTPete,

Some comparison shots like mentioned with and without lens would be great. I am about to pull the trigger on a VW-60 and if a person could get the same satisfaction from just zooming as opposed to getting a lens, that is great.

Jason.

I would like to see the chromatic aberation at the extent of a 16x9 screen.

Would CA be improved if the screen were curved? Don't see why it would be

Am I the only one here that thinks most of the posters in this thread are coming from the same computer?