CurtPalme.com Home Theater Forum

[barco_75]

Hi, I have a set color corrected c-elements and HD-214 lens from an old retroblock. I understand the C-elements are same as those found in the Cine 8 Onyx. I'm currently running a set of color filtered HD-145 with adapters. I'm wondering if I would gain any noticeable improvement by installing a set of HD-215 with my c-elements? The HD-215 doesn't have the outer focus adjustment where the HD-145 does. Seems like I might lose some sharpness at the sacrifice of greater contrast and less haloing.

Which is the better setup? Will one by vastly superior or just a minor improvement?

Also, I know there are many changes needed to make this a Cine 8 Onyx....I don't need information on this...just curious about the lens.

[CasetheCorvetteman]

Depends if you want ultimate sharpness or a bit better contrast ratio, HD-18 lenses would be a much better option.

HD-145s will be sharper than HD-215s by quite a bit.

[barco_75]

Thats what I was afraid off. I noticeable drop off in sharpness for a minor improvement in contrast. Are the HD-18 to be used with c-elements or without? I assume those would not work with my c-elements.

[CasetheCorvetteman]

HD-18 are what comes with XGs and G70s, not sure if the C elements are compatible or not. If you can get some HD-18s and they will fit those housing as well as be compatible with those C elements it would probably be worth the effort.

If those housings came from a rear projection TV they may be designed for a limited raster usage and have the edges blocked off more than front projector housings. A few rear pro TVs had housings that seemed to block out almost all the unused phosphor area, probably to reduce excess light spill. They also may not have adjustable lens flapping, since they were designed to suit one or two screen sizes.

Its not really a minor improvement in contrast, its about 50% better, but in the case of those lenses id say youd be forced to use a smaller tube face area to maintain good enough focus away from the middle. It might not be too much of an issue, those being short throw lenses, Kal would be the one to know since he had a Cine 8 Onyx.

[gjaky]

I have seen the HD215 in person, but is was mounted on a zentith pro 900x, the lack of corner focus was apparent even there. But I'm not even sure that if you compare HD-18 with the HD-145 using test patterns you'd find the HD-18 as sharp as the HD-145. But you won't tell that with movies, on the other hand the contrast improvement is huge, almost day and night.

[barco_75]

The HD-145 will bolt to the c-element housing but as far as I know they are not compatible. Too bad. I have no way to test that combination without a huge amount of work.

[CasetheCorvetteman]

No, HD-145 are AC lenses, you need LC lenses.

[barco_75]

Thats what I figured. Any other lens options? Anyone ever mount a set of HD-18 to a Barco? Are the C-elements curvature matched to a particular lens? Or is it an issue if the lens, c-element, and housing can physically be bolted together? The HD-145 and HD-215 bolts are spaced 100.41 mm apart (measuring horizontally and vertically).

What is the mounting distance of the HD-18? Is it comparable to the HD-145 and HD-215, these are both short throw?

[barco_75]

Digging in the archives "all about lens" I've found:


"Just to let you know.

Went back to the HD-117-12 lens and doing a 16/9 110 inch screen width (about 2,8m) with my BG 808s LC.

This lens is listed with a max. SW of 1,53m but i can get a full sharp corner and edge focus with my width !

Picture is supersharp with the P16 tubes.


ElTopo"

and


gcom007 wrote:
I'm still digging and I have some idea, but if someone can easily tell me what lens options I have on LC PT18's, I'd appreciate it!


You can use
HD214, HD215 which have no corner focus adjustment.
HD117-12 (up to 168cm width) or HD117-24 with corner adjustment
HD18 also with corner focus adjustment (chuchuf conversion, link to other forum)

But there is a difference in C-element (from left to right as listed above) and the adapter ring hight is different(I can upload a picture from this later)

large

Wil"

[CasetheCorvetteman]

The HD-144 are short throw, HD-145 are not, and i wouldnt say HD-18 are either.

I will take some pics when i get home, i have both types there.

[Decibel]

I have two Barco 808.

Both have hi-rez tubes LC, Cine 8 software and hardware modified.

One have HD18's lenses matching with Sony G70 colored c-elements.
The other have HD117-24's lenses matching with Barco's native clear c-elements.

[barco_75]

Thanks everyone! I was looking to shy away from the HD-215 if possible. if I do this as I didn't want to lose the focus ability that I have with my HD-145. Decibel your familiar with my c-elements, Barco Cine 8 Oynx. Have you tried it before? Would those work with the HD117 or Hd18? Which do you like better the HD117 or HD18 if you exclude the color correction?

[Decibel]

The electronic and tubes are identical in both projectors, the differences are the lenses and the c-elements.
Unfortunately, I had little time to compare them.
However the performances was great for both units with a little preference for the projector with HD117-24's because was capable to showing a focus really amazing.
Actually one unit (HD18's lenses) are waiting for a buyer.
I would to mount the other in a little studio-laboratory.

[barco_75]

Any idea if my c-elements will work with either?

[Decibel]

The problem is native plates of hd215's that are unusable for other type of lenses.

The options are:

1) HD215's with his native plates.
2) HD18's with diy plates.
3) HD117's with native Barco plates.

2 and 3 need diy supports for fix tubes into chassis, I don't know if option 1 need diy supports, perhaps yes.

[barco_75]

Seems like I'm going to go to the effort to do this I should go with the HD18 or HD117 since the HD215 focus is not that great. I know it doesn't matter when you are watching a movie, but i'm can't imagine going back the HD215 which I would guess would focus about as good as the HD-8.

[Decibel]

Steve you need LC chambers anyway.
I don't know if the LC chambers pulled from 708 retroblock are compatible with 808 chassis.
The dimensions of bare tubes should be identical ... perhaps you can try to use the 708's LC chambers but surely you'll must to do diy adapters.

[Decibel]

Remember: HD117's are short throw lenses.
With HD117's the projector need to place near the screen.

[barco_75]

The chambers are no good for the 8" Sony tubes. Your right I would need to check the image size. I have some flexibility because I just use my wall for my projection surface. Could you use tinted gycol with the HD-117 to make them color corrected? Or does that not work well in practice? I'll need to check out both lens further but at least I know my options.

[Decibel]

No tinted glycol in LC tubes because the liquid, matching with c-element, form a optical section between tube surface and the lense.