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post #181 of 292 Old 05-02-2011, 01:32 PM
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Quote:
Originally Posted by plew View Post

Picture mode: Film
Color space: Standard
Color temperature: 6500K
Gamma: A
Iris: 0 Fully open
Lamp power mode: Low
Hours: 87
Throw: 15 ft
Not calibrated, everything at o
Lumens: 516

That sounds like right in the ballpark of what would be expected for low lamp mode. I assume you also had the HDMI input mode set to standard. Did you also measure the high lamp lumens?

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post #182 of 292 Old 05-02-2011, 02:09 PM
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Quote:
Originally Posted by plew View Post
Picture mode: Film
Color space: Standard
Color temperature: 6500K
Gamma: A
Iris: 0 Fully open
Lamp power mode: Low
Hours: 87
Throw: 15 ft
Not calibrated, everything at o
Lumens: 516
amazing.. I can barely achieve that lumen output with the same throw, brand new lamp and lamp set to 'high' on my RS50 regardless of which color profile I am using.

With the hobbled CMS and gamma settings in the 50/60, the RS40 owners definitely got the best bang for the buck with the 2011 models.
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post #183 of 292 Old 05-02-2011, 02:17 PM
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I did not measure in high...not sure about HDMI standard. I left it at default.
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post #184 of 292 Old 05-02-2011, 02:41 PM
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Quote:
Originally Posted by plew View Post
Picture mode: Film
Color space: Standard
Color temperature: 6500K
Gamma: A
Iris: 0 Fully open
Lamp power mode: Low
Hours: 87
Throw: 15 ft
Not calibrated, everything at o
Lumens: 516
Hi,

Thanks for the measurement.

That is exactly the same measurement I had at 3 hours at mid-throw.

What size screen were you using?

Thanks.

Larry
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post #185 of 292 Old 05-03-2011, 01:31 PM
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120 diag, HP.
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post #186 of 292 Old 05-03-2011, 02:02 PM
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Quote:
Originally Posted by LarryChanin View Post

Hi Ron,

I want to thank you and Geof for the interesting discussion on meter accuracy.

If Chris is monitoring this thread it would be very informative if he could report back how JVC measures their projector's lumen output. I wouldn't be surprised if they are simply using an accurate light meter conforming to the CIE curve.

Larry

Hi Ron,

I found the following document which states how Philips measures their lamp output.

Benchmark tests to the quality of projector lamps

Quote:


3 MEASUREMENT PROCEDURE
3.1 Front projectors


The illuminance is measured by means of a 9 points measurement4. The average of the individual illuminance values is token [taken?] and multiplied by the surface area to get an ANSI lumen value. The illuminance is measured with a lux meter (Minolta CL-200) equipped with a cosine filter correction5.

The distance from beamer to screen is determined by a fixed frame on the wall with an aspect ratio of 4:3 (horizontal:vertical)6. By moving the beamer in transversal direction with maximum zoom7 the distance to the wall will be set. A white screen was obtained by a PowerPoint slice [slide?].

For the measurements on the DLP and LCD lamps respectively a DELL 2300MP projector and a SANYO PLC-XW55 projector are used.

The average temperature in the measurement room was 22° Celsius8.

All lamps are 15 minutes stabilised before starting any measurement9.

_______________________________________
4 IEC 61947-1:2002(E) - page 12
5 ibid - page 12
6 ibid - page 11
7 ibid - page 10
8 ibid - page 11
9 ibid - page 11


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post #187 of 292 Old 05-03-2011, 02:25 PM
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Originally Posted by plew View Post

120 diag, HP.

Hi,

Thanks.

That puts you at slightly less than mid-throw. For a 120" diagonal screen the minimum throw is 11'10", mid-throw is 15'10", and maximum throw is 24'2".

Interestingly, I also have a 120" diagonal screen and it is at a 16' throw. So our lamps are functioning virtually identically.

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post #188 of 292 Old 05-03-2011, 03:00 PM
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I only measured the center point. I did some quick scans and the average of nine points is lower. I did not do a full measurement though. I have the iris closed at -12 for 2D and is plenty bright.

Nice theater setup, Larry. I'm using my living room and would love to have a dedicated room.
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post #189 of 292 Old 05-03-2011, 03:30 PM
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Quote:
Originally Posted by plew View Post

I only measured the center point. I did some quick scans and the average of nine points is lower. I did not do a full measurement though. I have the iris closed at -12 for 2D and is plenty bright.

Yes, the brightness does drop off as you measure away from the center of the screen. On High lamp power my center measurement was 817 lumens, but my 9 point ANSI average was only 748 lumens.

My previous projector was brighter and I have become accustomed to more lumens, even though at 3300 hours my old projector may have been dimmer than my RS40 with a new lamp. I continue to experiment with the lens aperture setting. Currently it is at -5 with Normal lamp mode for normal viewing. However, I think that when it looses more lumens I will be forced to switch to High lamp mode. I never used high lamp mode on my previous projector.

Quote:


Nice theater setup, Larry. I'm using my living room and would love to have a dedicated room.

Thanks for the kind words. I love having a dedicated home theater, however, I rarely use it without a group of friends.

Larry
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post #190 of 292 Old 05-03-2011, 08:33 PM
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I have friends/family that want me to tear down walls so there's more seating space. We can currently sit 4-6 comfy, but only 3 glasses for 3D...

I have an 8 year old so movies are so limited at this time. I'm really sick of animation but it's so much fun to have guest come and experience front projection.

I remember Top Gun on a 30" with DD surround. It was great at the time.
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post #191 of 292 Old 05-04-2011, 07:54 AM
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Quote:
Originally Posted by LarryChanin View Post

Hi,

Thanks.

That puts you at slightly less than mid-throw. For a 120" diagonal screen the minimum throw is 11'10", mid-throw is 15'10", and maximum throw is 24'2".

Interestingly, I also have a 120" diagonal screen and it is at a 16' throw. So our lamps are functioning virtually identically.

Larry

Hi plew,

I have taken a closer look at Projection Central's calculator.


Projection Pro Calculator for JVC DLA-RS40


Although for a 120" diagonal screen its graphic shows 15'10" in the middle of the minimum and maximum throw distances, if we calculate the mid-point of this throw range it comes out to 18'.

So I'm not sure what the 15'10" distance represents.

If we were really at mid-throw would could have expected an increase of about 11% if we were to move to the minimum throw distance. Since we are at about 33% of the throw range we can expect an increase of about 7.8% in moving to the minimum throw distance. This would yield an out-of-the-box, peak center screen lumens of about 880 lumens for usable settings with High lamp mode.

In my case I don't find it practical to move the throw distance.

Larry
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post #192 of 292 Old 05-04-2011, 08:35 AM
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Quote:
Originally Posted by plew View Post

I have friends/family that want me to tear down walls so there's more seating space. We can currently sit 4-6 comfy, but only 3 glasses for 3D...

I have an 8 year old so movies are so limited at this time. I'm really sick of animation but it's so much fun to have guest come and experience front projection.

I remember Top Gun on a 30" with DD surround. It was great at the time.

Hi,

Prior to moving to Florida my wife and I had the luxury of pouring over countless floor plans. After we found a suitable plan, and a builder willing to do major changes, we were able to "tear down" walls, remove windows, redesign and add walls on paper without the inconvenience of actually living through an actual demolition.

Initially I only purchased an emitter and two pair of glasses, since I wasn't sure I would like 3D. After my second 3D movie, an animated movie, I ordered another 4 pair. I still don't have enough for all my seating. I'll probably waiting to see if pricing decreases. JVC isn't exactly giving these things away, are they?

Yes, technology marches on. I was trying to avoid being an early adopter on 3D front projection, but my existing projecter died and I found myself reluctantly thrust into the "bleeding edge" again.

Larry
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post #193 of 292 Old 05-04-2011, 08:44 AM
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Attached is an updated Lux to Lumens Excel spreadsheet. You can now enter the projector-to-screen throw distance and the zoom ratio will be calculated. A zoom ratio = 1.0 corresponds to max. telephoto setting, which givens you the smallest possible image size. At the other zoom extreme, max. wide angle, the zoom ratio = 2.0 which gives you the largest possible image size. This zoom ratio calculator is only intended to work for the zoom lens used on the JVC projectors (RS40/50/60/X3/X7/X9). Note in the spreadsheet I only show the zoom ratio to one decimal place since this only intended to be an approximation.


For those of you that use the spreadsheet, please include the zoom ratio when you post your projector's measured lumens.

UPDATE - May 9, 2011 - I have replaced the attached file with a corrected version of the Excel spreadsheet.

 

Lux to Lumens Calc - v2.zip 4.287109375k . file

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post #194 of 292 Old 05-04-2011, 09:49 AM
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Quote:
Originally Posted by Ron Jones View Post

Attached is an updated Lux to Lumens Excel spreadsheet. You can now enter the projector-to-screen throw distance and the zoom ratio will be calculated. A zoom ratio = 1.0 corresponds to max. telephoto setting, which givens you the smallest possible image size. At the other zoom extreme, max. wide angle, the zoom ratio = 2.0 which gives you the largest possible image size. This zoom ratio calculator is only intended to work for the zoom lens used on the JVC projectors (RS40/50/60/X3/X7/X9).

For those of you that use the spreadsheet, please include the zoom ratio when you post your projector's measured lumens.

Hi Ron,

For my peak center screen lumens of 817 with useable settings and High lamp mode my zoom ratio was 1.7.

Can we use the zoom ratio to extrapolate lumens for minimum throw?

Thanks.

Larry
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post #195 of 292 Old 05-04-2011, 10:10 AM
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Quote:
Originally Posted by LarryChanin View Post

Hi Ron,

For my peak center screen lumens of 817 with useable settings and High lamp mode my zoom ratio was 1.7.

Can we use the zoom ratio to extrapolate lumens for minimum throw?

Thanks.

Larry

Larry -

I had considered that but I haven't taken enough data points for the lumens vs. zoom setting to verify if it is linear. If it is then the additional lumens to be gained by going to the shortest throw (i.e., with the zoom having a zoom ratio of 2.0) would be:

(2.0 - Zoom Ratio) x 23%

Thus in your case with a zoom ratio of 1.7 this would be:
(2.0 -1.7) x 23% = 6.9%

Thus if the light loss is linear as you zoom from wide angle to telephoto then your lumens would increase about 6.9% if you relocated your projector to the shortest throw possible for youir screen size. Note in the spreadsheet I only show the zoom ratio to one decimal place since this is only intended to be an approximation.

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post #196 of 292 Old 05-04-2011, 10:27 AM
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Quote:
Originally Posted by LarryChanin View Post

Hi plew,

I have taken a closer look at Projection Central's calculator.


Projection Pro Calculator for JVC DLA-RS40


Although for a 120" diagonal screen its graphic shows 15'10" in the middle of the minimum and maximum throw distances, if we calculate the mid-point of this throw range it comes out to 18'.

So I'm not sure what the 15'10" distance represents.

If we were really at mid-throw would could have expected an increase of about 11% if we were to move to the minimum throw distance. Since we are at about 33% of the throw range we can expect an increase of about 7.8% in moving to the minimum throw distance. This would yield an out-of-the-box, peak center screen lumens of about 880 lumens for usable settings with High lamp mode.

In my case I don't find it practical to move the throw distance.

Larry

Quote:
Originally Posted by Ron Jones View Post

Larry -

I had considered that but I haven't taken enough data points for the lumens vs. zoom setting to verify if it is linear. If it is then the additional lumens to be gained by going to the shortest throw (i.e., with the zoom having a zoom ratio of 2.0) would be:

(2.0 - Zoom Ratio) x 23%

Thus in your case with a zoom ratio of 1.7 this would be:
(2.0 -1.7) x 23% = 6.9%

Thus if the light loss is linear as you zoom from wide angle to telephoto then your lumens would increase about 6.9% if you relocated your projector to the shortest throw possible for youir screen size. Note in the spreadsheet I only show the zoom ratio to one decimal place since this only intended to be an approximation.

Hi Ron,

Yes, when I use a bit more precision I get 7.2% instead of 6.9%. The 7.2% isn't too far from my 7.8% value that I obtained by using Projector Central's calculator.

By the way, do you have any idea what the middle value on Projector Central's throw range is supposed to represent? Do you agree that its not the mid-throw value?

Thanks.

Larry
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post #197 of 292 Old 05-04-2011, 12:45 PM
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Quote:
Originally Posted by LarryChanin View Post

Hi Ron,

Yes, when I use a bit more precision I get 7.2% instead of 6.9%. The 7.2% isn't too far from my 7.8% value that I obtained by using Projector Central's calculator.

By the way, do you have any idea what the middle value on Projector Central's throw range is supposed to represent? Do you agree that its not the mid-throw value?Thanks.

Larry

I noted that if you use the Projector Central calc for the RS40 in combination with a 120" diagonal 16 x 9 screen it correctly shows the throw range as 11' 9" to 24' 2" but seems to show the mid-point as 15' 11". Clearly this is not the mid-point of the possible throw ranges. It appears they are using some nolinear scale on their throw distance slider bar.

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post #198 of 292 Old 05-05-2011, 09:27 AM
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Attached is another update (May 5, 2011 version) of the Excel spreadsheet for doing the Lux measurement to projector lumens calculation. This new version provides an estimate of what the peak lumens (i.e., center screen measurement) would be if you were to move the projector to the shortest throw distance possible for your screen size (i.e., with the lens set for maximum zoom).

 

Lux to Lumens Calc.zip 3.380859375k . file

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post #199 of 292 Old 05-06-2011, 10:34 AM
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Quote:
Originally Posted by Ron Jones View Post

I noted that if you use the Projector Central calc for the RS40 in combination with a 120" diagonal 16 x 9 screen it correctly shows the throw range as 11' 9" to 24' 2" but seems to show the mid-point as 15' 11". Clearly this is not the mid-point of the possible throw ranges. It appears they are using some nolinear scale on their throw distance slider bar.

Hi Ron,

I sent the following question to the Projector Central folks:

Subject: JVC DLA-RS40 throw distances

I have a curiousity question about what the value that appears in the center of the throw range graphic is supposed to represent. For example, for a 120" diagonal image the minimum throw distance is shown at 11'10" and the maximum throw distance is 24'2" with the value in the middle at 15'11". The mid-point of the throw range is actually 18' so I was wondering what the 15'11" is supposed to represent.

Thanks.

Larry


Here is their response:

The throw range slider is adjusting the zoom ratio of the projector. Throw distance dowa not change in a straight line as you asjust the zoom, which means that the half-way point (half the lens' zoom ratio) is not the middle value in the throw distance range.

Tim

--- ProjectorCentral Staff
http://www.projectorcentral.com


So it seems the value in the middle of the throw range is the point at half the len's zoom ratio and not the mid-throw distance.

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post #200 of 292 Old 05-06-2011, 11:32 AM
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Quote:
Originally Posted by LarryChanin View Post

Hi Ron,

I sent the following question to the Projector Central folks:

Subject: JVC DLA-RS40 throw distances

I have a curiousity question about what the value that appears in the center of the throw range graphic is supposed to represent. For example, for a 120" diagonal image the minimum throw distance is shown at 11'10" and the maximum throw distance is 24'2" with the value in the middle at 15'11". The mid-point of the throw range is actually 18' so I was wondering what the 15'11" is supposed to represent.

Thanks.

Larry

Here is their response:

The throw range slider is adjusting the zoom ratio of the projector. Throw distance dowa not change in a straight line as you asjust the zoom, which means that the half-way point (half the lens' zoom ratio) is not the middle value in the throw distance range.

Tim

--- ProjectorCentral Staff
http://www.projectorcentral.com


So it seems the value in the middle of the throw range is the point at half the len's zoom ratio and not the mid-throw distance.

Larry

Perhaps they are using the mechanical center point of the zoom. for example, with a manual zoom lens where you rotate the zoom ring on the lens 300 degrees to go from min. to max. zoom they may consider the mid-point as having 150 deg. rotation. With a power zoom that takes 10 seconds to go from min. to max. zoom they may consider the 5 sec. point as the middle of the zoom.

On the other hand I would consider the middle of the focal length range of the zoom as the middle point. While I haven't seen specific details for the focal length of the lens used in the RS40/50/60 but the spec. sheet for HD990(which also has a 2:1 power zoom lens) lists the focal length of its zoom as:

21.4mm to 42.8mm; and the f-stop changes from f=3.2 to f=4.0 as you zoom.

In the case of the HD990 the middle of this zoom range would be 32.1mm and that focal length would be appropriate to be called the mid-zoom point. Throw distance is directly proportional to focal length so the mid-point for the zoom lens' focal length would also be the mid-point for throw distance.

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post #201 of 292 Old 05-06-2011, 11:55 AM
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I have once again updated the lux-to-lumens Excel spreadsheet. This new version corrects an error in yesterday's (May 5, 2011) version for the estimation of the increased lumens that would be expected by repositioning the prejector to the shortest possible throw location. Based on my measurements reported a couple of weeks ago, going from the shortest throw to the longest throw postions decreases the lumens by approx. 23%. However, if you look at it for going from the longest throw position to the shortest throw this represents approx. a 30% increase in lumens (i.e., 1/0.77 = 1.3 or a 30% increase). I had incorrectly used the 23% value for the calculation in the spreadsheet where it should have been the 30% value since the spreadsheet is attempting to estimate what would be the effect for going from a longer throw to the shortest throw distance possible for the selected screen size. This has been corrected in the attached version (May 6, 2011).

Note the estimate for the increased lumens when using shortest throw that is provided by the spreadsheet is only a rough estimate.

 

Lux to Lumens Calc.zip 3.380859375k . file

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post #202 of 292 Old 05-06-2011, 12:19 PM
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Quote:
Originally Posted by Ron Jones View Post

Perhaps they are using the mechanical center point of the zoom. for example, with a manual zoom lens where you rotate the zoom ring on the lens 300 degrees to go from min. to max. zoom they may consider the mid-point as having 150 deg. rotation. With a power zoom that takes 10 seconds to go from min. to max. zoom they may consider the 5 sec. point as the middle of the zoom.

On the other hand I would consider the middle of the focal length range of the zoom as the middle point. While I haven't seen specific details for the focal length of the lens used in the RS40/50/60 but the spec. sheet for HD990(which also has a 2:1 power zoom lens) lists the focal length of its zoom as:

21.4mm to 42.8mm; and the f-stop changes from f=3.2 to f=4.0 as you zoom.

In the case of the HD990 the middle of this zoom range would be 32.1mm and ???

Hi Ron,

I couldn't find anything on JVC's website for f-stop, but the Projector Central calculator has the same f-stops listed for the DLA-RS40.

Larry
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post #203 of 292 Old 05-06-2011, 12:58 PM
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Quote:
Originally Posted by LarryChanin View Post

Hi Ron,

I looks like your response was inadvertently truncated.

Did you mean to add f=3.6 at the end of the last sentence?

I couldn't find anything on JVC's website for f-stop, but the Projector Central calculator has the same f-stops listed for the DLA-RS40.

Larry

Larry - I did an edit that finished the sentence that was cut off in my earlier post.

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post #204 of 292 Old 05-06-2011, 01:16 PM
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I just got my electronic copy of Twice, an industry trade rag. JVC just anounced a large but unspecified layoff at its NJ headquarters and elsewhere. This is the third layoff in two or three years and reflects further consolidations and sort of substantially exiting the audio market. I have no info as to JVC Pro, the division that handles the RS projectors, a lot of the discussion concerned the comsumer division which handles the X series. Somebody I am sure will post the link here and in the other JVC threads.

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post #205 of 292 Old 05-06-2011, 01:28 PM
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Quote:
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I just got my electronic copy of Twice, an industry trade rag. JVC just anounced a large but unspecified layoff at its NJ headquarters and elsewhere. This is the third layoff in two or three years and reflects further consolidations and sort of substantially exiting the audio market. I have no info as to JVC Pro, the division that handles the RS projectors, a lot of the discussion concerned the comsumer division which handles the X series. Somebody I am sure will post the link here and in the other JVC threads.



Layoffs Come To JVC America

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post #206 of 292 Old 05-06-2011, 08:35 PM
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I finally got my LX1330B, and here's what I got (9-point ANSI using Ron's spreadsheet):

Picture mode: Film
Color space: Standard
Color temperature: 6500K
Gamma: A
IRIS: 0 (fully open)
Throw: 17.7 ft (near shortest throw for image size)
Hours: 104 (almost all hours on the lower lamp setting)

Lamp: High
Lumens: 856 (edit: - in retrospect I didn't really let it warm up in this mode...)

Lamp: Normal (low)
Lumens: 586

With calibrated settings:
Lamp: Normal (low)
Lumens: 577

Iris -5 = 530 lumens (my "brighter" setting for cinemascope at 168" diag)
Iris -10 = 444 lumens (my "preferred" setting for cinemascope at 168" diag - probably a bit dim for some)
Iris -15 = 359 lumens (my "widescreen" setting for 133" diag - too bright for me)

I'm lucky enough to still be able to run with the iris closed or partly closed for much of my viewing. Thankfully my bulb is such that I'm only dropping a few points of gain to reach 6500K at 100%, at least at this point in its life. From the JVC default 6500K settings, I only need -5 green and -1 blue.
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post #207 of 292 Old 05-07-2011, 09:42 AM
 
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Do you guys think a 166" HP (2.35 2.4 gain version) screen would be to much for this PJ at medium throw? Light controlled room PJ at center/eye level
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post #208 of 292 Old 05-07-2011, 10:49 AM
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Originally Posted by d3coy3d View Post

Do you guys think a 166" HP (2.35 2.4 gain version) screen would be to much for this PJ at medium throw? Light controlled room PJ at center/eye level

Is that using an anamorphic lens to do a horizontal stretch or you planning to just zoom the projector's lens to fill the 2.35 screen? How far off the centerline of the screen does your seating extend (since the HP screen gain drops as you move off of the center position)? In any case when seated near the center postion you should get a relatively bright 2D image. If using the zoom method for 2.35 when viewing from the center seating and with the RS40 operating in high lamp mode, with the iris fully open, and with a new bulb you will get nearly 2X above the frequently recommended minimum 12 ft. lamberts light level. This is good since you will be able to tolerate bulb dimming with age and still have an adequately bright image for 2D viewing. For 3D it will be dimmer, but still adequate for most viewers, especially if you don't zoom to fill the 2.35 screen (i.e., keeping the 16x9 format).

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post #209 of 292 Old 05-07-2011, 10:51 AM
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Quote:
Originally Posted by d3coy3d View Post

Do you guys think a 166" HP (2.35 2.4 gain version) screen would be to much for this PJ at medium throw? Light controlled room PJ at center/eye level

Depends on how bright you want the image, whether or not you'll be using an anamorphic lens, and if you want to run on the lower lamp setting.

My screen is very similar in size to what you're looking at (mine is 155" x 65" 2.40:1 versus your 153" x 65" 2.35:1). The old HP material offers me a bit more gain in my prime seats. In cinemascope mode with calibrated settings, I'm getting about 16 Ft-Lamberts on the normal (lower) lamp mode with the iris wide open, which is a brightness level many viewers like. I'm only able to get to this level because I have a fairly fresh and good performing lamp, because I'm near the shortest throw, and because of the level of gain my old HP fabric offers (about 2.6-ish from my viewing position).

I find great satisfaction above 12 Ft-Lamberts with the large image size and my close viewing distance. I turn it up to 14-ish Ft-Lamberts for darker features (i.e. the dim Harry Potter films), but don't often go brighter. But that's my preference. Some like it substantially brighter.

At 153" wide, if you're not using an anamorphic lens you'll require the projector to be illuminating about 92 square feet when throwing a full-width image (works out to about 86 x 153). If you can figure out what sort of gain you'll see from your main seating, you can do a little math to figure out what sort of lumens from your projector will work for your desired brightness.

If I'm doing the math right, this is what I see:

Assuming you want 16 Ft-Lambers
Assuming 2.2 gain from your prime seats
Assuming 92 square feet illuminated for full-width projection

16 / 2.2 = 7.27
7.27 * 92 = 669 Lumens

That would most likely be unachievable in "Normal" bulb mode, but should be easily achievable in "High" bulb mode.

If you use a high quality anamorphic lens, you'll gain some brightness, and the equation changes again. The right lens may provide enough brightness to run your setup in "Normal" bulb mode.
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post #210 of 292 Old 05-08-2011, 04:26 AM
 
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Quote:
Originally Posted by Ron Jones View Post

Is that using an anamorphic lens to do a horizontal stretch or you planning to just zoom the projector's lens to fill the 2.35 screen? How far off the centerline of the screen does your seating extend (since the HP screen gain drops as you move off of the center position)? In any case when seated near the center postion you should get a relatively bright 2D image. If using the zoom method for 2.35 when viewing from the center seating and with the RS40 operating in high lamp mode, with the iris fully open, and with a new bulb you will get nearly 2X above the frequently recommended minimum 12 ft. lamberts light level. This is good since you will be able to tolerate bulb dimming with age and still have an adequately bright image for 2D viewing. For 3D it will be dimmer, but still adequate for most viewers, especially if you don't zoom to fill the 2.35 screen (i.e., keeping the 16x9 format).

At the moment, I plan using the zoom method for 2.35. Seating will be directly center with projector right behind the 2nd row of seating, which is mid throw (24'). I have the JVC RS2 now on a 140" 2.35 2.8 HP gain at max throw and love the image. If i can just calculate what those fL are then Ill have a better understanding of what 12 fL equates too.
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