CurtPalme.com Home Theater Forum

**Curt Palme**

Apparently I did a booboo some time ago and sent out a set of color corrected HD6C lenses instead of a set of HD144/145.

I know the HD6C came off an NEC, and they are indeed color corrected/tinted. Are they on par with the HD144/145, or does someone have some hard specs that the later 144/145 lenses have a higher resolution? I've never seen a difference, but want to make good with the customer/forum member.

Thanks!
Curt

**AnalogRocks** · Posted: Sat Mar 07, 2009 4:48 am Post subject:

Where's Joust? He did all this testing some time ago.

benareeno · Joined: 22 Mar 2006 Posts: 1614 Location: ottawa, canada

I think they're plastic...on par with HD8's, I guess.

They're filtered, but they're green and red not cyan and magenta...I would say a big step down from 144/145's.

kschmit2 · Posted: Sun Mar 08, 2009 9:22 am Post subject:

HD-6C are already hybrid glass/plastic lenses like any of the later lens models incl. HD144/145, HD10 and so on.

I also have a set of color corrected and color filtered HD-6C ML lenses here (from a NEC PG9000), and sold a set to a fellow in Italy about 2 years ago. But I never compared them to the HD-145 lenses on my PG Plus.

IIRC HD-6C lenses were spec'd at either 6 or 8 lp/mm though, while HD 145 lenses are spec'd at 10 lp/mm

Kai

Mark_A_W · Posted: Mon Mar 09, 2009 10:45 am Post subject:

If I was the customer, I would accept 145s instead of 144s (assuming 145s are filtered).

But I'd be spitting chips if you sent me HD-6's.

mc86 · Posted: Wed Feb 02, 2011 3:33 am Post subject:

Hi -

Just to update this thread and seek a little input...On the penultimate (one of my fancier words) post on the sticky thread "About All Lenses" a US Precision Lens PDF doc was posted that stated explicitly (below) that the HD-6Cs were spec'd at 10 lp/mm as well. This differs from the above posts regarding the differences between HD-6Cs and the 144/145s.

I haven't found any direct comparison tests anywhere on the HD-6C vs. HD144/145. It seems clear my ECP 4500 would really benefit from dumping the colored glycol and switching to tinted lenses. Any advice on if they should be tinted HD-6Cs or HD-144/145s? I have some flexibility in throw distance still. I don't know about mounting details for the HD144/145.

Thanks,
Matt

From the PDF:
"With the CRT spot size approaching 0.1 mm, the projection lenses for HDTV and
DATA/GRAPHICS applications must have a maximum MTF at 10 lp/mm. The lens shown in
Figure 30 is capable of providing this level of performance. It has been sold for a number of
years under the name HD-6. The field of view of the lens is 46”, it covers 5” raster diagonal
on the CRT."

Sticky thread on "About all Lenses" is:
https://www.curtpalme.com/forum_archived/viewtopic.php@t=2761.html

kschmit2 · Posted: Wed Feb 02, 2011 6:46 am Post subject:

well, I have since done some testing with the HD-6C ML lenses on my PJ, and they are noticeably softer than the HD-145 lenses, and halos are much worse (almost non-existent with HD-145 lenses).

Halo improvement alone warrants a switch to HD-144/HD-145 lenses.

But if anyone is interested in a set of color-filtered and color-corrected HD-6C lenses, I still have a set here that I can let you have for cheap (only shipping those to Europe though).

Kai

gjaky · Joined: 05 Jun 2010 Posts: 2802 Location: Budapest, Hungary

what about HD-6C contra HD-8? The color filtering itself worth the effort the mess with lens adapters on my marquee?

mc86 · Posted: Wed Feb 02, 2011 4:04 pm Post subject:

Gjaky and Kai -

Thanks for the input on the HD6s vs the 144/145s! I am a noob, but think I have this all correct. The HD-6 and HD-8 are same quality/spec family (deliver same image qualities), but the HD-8 simply has to be bigger for the 8" tubes. The HD6/HD8s came tinted and clear. Same with the 144/145s. So, there are two issues we should not mix-up:

1) Color filtering (the tinted lenses, not "color correction") vs "clear" lenses. Apparently, though I have not gotten this far myself, there is no debate on this. For your case, the HD8 clear to HD8 tinted would be upgrade #1. See below.
https://www.curtpalme.com/forum_archived/viewtopic.php@t=3820.html
On a related note, somewhere on the CP forums I read about using gel-type color filters as a very inexpensive alternative to tinted lenses, albeit at the cost of having to drive the tubes harder for increased brightness. This solution also comes with a little diffusive softness. This could save on buying retro kits for the 8" guns.

2) Other lens performance improvements would be gained by switching to 144/145 regardless of tint. These include reduced haloing, improved corner focus, possibly resolution, etc. are all to be better with the 144/145s (again, FAQ link above). The fantastic PDF technical overview of lenses, configuration trade-offs, etc. I quoted above is concise, must-read info for CRT infants like me. Again, it is at the very end of this thread:
https://www.curtpalme.com/forum_archived/viewtopic.php@t=2761.html

Bottom line: the order should be HD6 or H8 clear worst < anything tinted and 144/145 < tinted 144/145. I am in the midst of making my mind up on this. For ~$100 with shipping I hope to get some tinted HD6s soon. I will post HD6 clear vs HD6 tinted for folks, possibly with colorimetric data. After that setup is done and I have cut my teeth on the ECP 4500, I'll step up and spend the ~$200(?) on the tinted 144/145s. I could then keep those for use (someday!) when I am ready to step-up to an intermediate 8"CRT PJ...or maybe I'll leap to a 9"LC advanced! (ahhh...to dream, to dream.)

Thanks!
Matt in Pittsburgh, PA
pursuit can be perfect without possession.

the_maniac · Joined: 10 Jul 2009 Posts: 111 Location: Austria - Europe

i don't see much sense in spending money on HD144/145 for an 7" ESF projector, because the tubes will limit the focus not the lenses. you better save your money for an 9" LC

Revox · Joined: 13 Feb 2008 Posts: 158

When i compare the Barco 701s with T180 Tubes and the HD 145 my 8500 with HD 145. I think both tubes use the same Phosphor. My Marquee is much much sharper! Especially when the picture is brighter. You wont use a ESF Pj in high brigthness.

I think with optics its a little bit like with cables in Hifi. A lot of people think they can upgrade in a new product range with better cables and they create a new hype. A different optics would not change the basic performance of the PJ.

mc86 · Posted: Fri Feb 04, 2011 5:19 am Post subject:

The big improvement I expect to see will be result of the tinted lenses more than the improved optics of the 145s. As I expect to step-up to an 8500 (using same 145s) in maybe two years or so, this purchase is logical and practical step. I think going to an advanced 9"LC from a 7" would be imprudent...thoughts?

Finally, while I'm not Daddy Warbucks, this won't break my bank as Curt extended a very fair price. I'm following Curt's (and others) recommendation to skip the tinted HD6s now.

lest I forget: continued thanks!
Matt

MrBlonde83 · Joined: 16 Mar 2009 Posts: 132 Location: Lansford, PA

Yes I agree it would be pointless... I'd just assume wait for that marquee I have my eye on in the future or something, just have to find a herd of oxen to lift it. This one is heavy enough.

mc86 · Posted: Mon Jul 09, 2012 1:13 am Post subject:

Anyone know the throw difference between an HD-6 and HD-145? I see stuff all over stating the 145s are a little longer than the 144s, but can't find a HD-6 to HD-145 comparison. I know, I know....the lens sharpness isn't the issue for a 7"ES machine...but halo reduction comments above and other reasons push me to have an inquiring mind. And inquiring minds want to know!

Matt

CIR Engineering · Posted: Mon Jul 09, 2012 3:55 am Post subject:

Matt,

I have a nice set of color filtered HD-145N lenses here that I will give you for the price of shipping. Let me know if you want them Smile

Kind regards,
craigr

zGman · Joined: 22 May 2006 Posts: 599

Jump on that and Quick!
very nice offer and 145N's are the best...!
G

gjaky · Joined: 05 Jun 2010 Posts: 2802 Location: Budapest, Hungary

I wish I have an offer like that here in europe...

mc86 · Posted: Mon Jul 09, 2012 1:57 pm Post subject:

PM sent to Craig -- I'll make a small donation to the site for his generosity, too. Gotta love this site -- yesterday I offer-up some nice SD187s to pay it forward...and it comes right back!

What is funny is I had JUST paid curt for a set...so now I'll have two sets. Indeed, pieces for a softblend are starting to come together...albeit as fast as cold-flowing molasses.

Looks like I'll be the one to report on the throw differences on the HD6 and 145 lenses. Once I know, I post that on the all about lenses thread and will link to it on this one. Wink

Matt