HP LP2475w (Possible new IPS)

Badd said:
This gets a little confusing. So on the one hand, the results in the review dont look quite right, and it almost looks like the brightness OSD control adjusts contrast and visa versa. see the thread here discussing it:

http://www.tftcentral.co.uk/forum/YaBB.pl?num=1220470066

would be interested to hear your views about the backlight control or lack of it. that link has readings of luminance, black point etc if we assumed the controls were the wrong way round.
Click to expand...


It looks like the contrast control is a digital white level control, which is actually the correct thing to do. The problem is there's no backlight luminance control, which is normally called brightness on most monitors, so there's no way to dim the backlight. That means the only way to reduce the white luminance is to reduce the contrast. That's why the contrast is so poor. That's a serious design limitation. The 30" Hazro only has a backlight luminance control, which is why it's not affected by the problem.
Click to expand...


If what Snowdog and toasty say is true, then i agree that this is such a dissapointment. I am using Dell 2405 FPW which cannot adjust contrast. Why would i jump from one evil to another ? But this time it would be the brightness/luminance control ..... :rolleyes:

I dearly hope the HP does not have such limitation as well :eek:


The NEC 2690 seems to have the best OSD controls for changing everything perfectly. To top it off it has an internal lut and is capable for a 1 push button caliberation which is awesome imho :D
 
Here in Finland few have got LP2475W and except for TFT-standard too high default brightness setting they haven't reported any flaws. One user commented black level to be good when looked in dark room and that black and white (=contrast) look better than in Dell 2007FP.
So I think we can safely conclude that HP has selected reasonable backlight with real brightness control and that contrast controls actual contrast.


Badd said:
This gets a little confusing. So on the one hand, the results in the review dont look quite right, and it almost looks like the brightness OSD control adjusts contrast and visa versa. see the thread here discussing it:
http://www.tftcentral.co.uk/forum/YaBB.pl?num=1220470066
would be interested to hear your views about the backlight control or lack of it. that link has readings of luminance, black point etc if we assumed the controls were the wrong way round.
Click to expand...
Results are slightly curious but still make much sense.
If you look that graph in review contrast stays as ralatively stable from 0 to 50% brightness (which should adjust backlight), above that it looks like panel simply couldn't keep up with light output and backlight just blows though blocking of panel and flushes contrast ratio down from toilet.
In "reverse" test black level stays same all the time regardless of contrast adjustment (which sets difference between black and white) so that hints backlight being at same steady level all the time. And consistent contrast drop below 50% setting hints also that it's panel blocking which is lowering luminance and setting of 60% already maxes amount of light allowed through panel and anything more just starts blending more and more bright shades to white.

Only wague thing is that if you look measured values 400-450cd/m2 luminance looks like some turning point. In original test black level stayed nearly same below that and contrast ratio started dropping at same pace as luminance which might hint panel blocking being used. Now contrast ratio of all LCDs types apparently doesn't stay stable when backlight is dimmed so maybe minimum leakage is just that bad... but still looks like brightness setting might use also panel blocking below that point.

But if 50% brightness gives ~530 cd/m2 luminance maxing it makes you need this!
http://www.baader-planetarium.com/sofifolie/sofi_start_e.htm
 
Ok...so played around with it a lil bit more...getting better not quite there yet...I think I can go lil lower on black point and increase the contrast some more...

this is with brightness at 3 btw...

2827191255_1c57aceaa8_o.jpg
 
E.T said:
Results are slightly curious but still make much sense.
If you look that graph in review contrast stays as ralatively stable from 0 to 50% brightness (which should adjust backlight), above that it looks like panel simply couldn't keep up with light output and backlight just blows though blocking of panel and flushes contrast ratio down from toilet.
Click to expand...

Actually I have looked at the results from changing both the contrast and "brightness" controls with respect to that 26" Hazro (getting further off topic here). I see Zero evidence that there is any backlight control, just changing amounts of panel blocking.

This is a huge gaping design flaw that screams: DO NOT BUY THIS MONITOR! Hazro seriously dropped the ball here.

This is such a gaffe that I would look much more critically at all aspects of any other Hazro product. If we want to discuss this further perhaps the Hazro deserves its own thread.

Back on topic. The HP looks to have proper and good backlight control.
 
Snowdog said:
Back on topic. The HP looks to have proper and good backlight control.
Click to expand...

IT does indeed, you can see it when controlling the OSD. The power usage values posted by someone else a few pages back also back this up (as brightness goes down, so dose the power consumption, down to about 57w at 0%).

I was the first to question if the Hazro used panel blocking over on the OcUK forums - you can tell as the thing stayed very hot (and bright) with the brightness down to 0%.

The HP is also nice in that it doesn't dry my eyes out with heat radiating from the panel.
 
Snowdog said:
Back on topic. The HP looks to have proper and good backlight control.
Click to expand...
Yep, with very good connectivity this looks like the screen what Dell 2408WFP should have been instead of that "lag champion".

It's good thing we're finally getting somewhere in availability of affordable good image quality monitors...
Only input lag is higher at 1-2 frames but if LG's availability keeps going forward long time I'll get this HP instead.
 
This looks like a very promising display. Even without A-TW polarizer it will not suffer from severe washout like the S-PVA panel in the Dell, nor the perceived brightness changes from left to right listed as the problem.

Additionally if it can handle HD sources like gaming consoles with little overscan and proper aspect representation it will be a winner. Judging from older HP models this shouldn' t be a problem.

Hopefully this will lead the charge to a paradigm shift away from the Samsung pattern of having 40 different 22" TN-based models, and we'll see some more competition for IPS monitors worldwide.


E.T said:
Yep, with very good connectivity this looks like the screen what Dell 2408WFP should have been instead of that "lag champion".

It's good thing we're finally getting somewhere in availability of affordable good image quality monitors...
Only input lag is higher at 1-2 frames but if LG's availability keeps going forward long time I'll get this HP instead.
Click to expand...
 
Moogle Stiltzkin said:
this is such a dissapointment. I am using Dell 2405 FPW which cannot adjust contrast. Why would i jump from one evil to another ? But this time it would be the brightness/luminance control
Click to expand...
Relax about "panel dimming". As I told you it's a common thing
used for best monitors including 2490, 2690, etc.
 
albovin said:
Relax about "panel dimming". As I told you it's a common thing
used for best monitors including 2490, 2690, etc.
Click to expand...

Why? Pixel dimming will, by default, reduce the contrast ratio and produce a worse black level, which is already a weak point of IPS panels. I cannot believe that the NEC's don't have a dimmable backlight, can you provide a source please - I'm genuinely interested?
 
Agreed,

In the case of the Hazro, where only panel dimming seems to be used to lower brightness, it is a disaster. 0.60 cdm/2 blacks ????????

The NECs don't use it solely though. Snowdog's review of his LCD 2490 showed that contrast is not affected until less than 175 cdm/2 white brightness is used on the 2490, and I've found the same thing on the 2690, approximately. This means that panel blocking is not employed until below that level is reached. In my NEC's case, I find it turns the whites a tiny bit pink/yellow and contrast begins to reduce accordingly.

This is the case with other monitors of different technologies where backlight regulation is not wide enough to go from 500 cdm/2 (!!!) to 140 cdm/2. The fact that the HP gets close is very good (judging from H3ndrix's screenshot), especially with no measurable loss of contrast.

But this is why earlier in this thread, in my extended diatribe about energy use, I mentioned it is difficult to calculate purely from a technology standpoint (ie. IPS vs TN vs *VA) because in those (seemingly rare) cases where certain manufacturers use panel blocking exclusively, power usage is equal at all brightness levels. For others they generally will go down to near the limits of the backlight regulation, THEN employ blocking.

All told, the HP's approach is the proper one seemingly, methinks :)


philjohn said:
Why? Pixel dimming will, by default, reduce the contrast ratio and produce a worse black level, which is already a weak point of IPS panels. I cannot believe that the NEC's don't have a dimmable backlight, can you provide a source please - I'm genuinely interested?
Click to expand...
 
10e said:
Additionally if it can handle HD sources like gaming consoles with little overscan and proper aspect representation it will be a winner. Judging from older HP models this shouldn' t be a problem.
Click to expand...

I think this is the only bit of information/confirmation I am waiting on before I pull the trigger. Specifically PS3 over HDMI, although with 2 DVI connections i guess it may not matter that much.
 
albovin said:
Relax about "panel dimming". As I told you it's a common thing
used for best monitors including 2490, 2690, etc.
Click to expand...

Not from the brightness control. The brightness control only changes the backlight output as it should on the 2490/2690.

After that point you can resort to a custom profile or "low brightness mode". if you need it. I only need to do this if I am working at night. The minimum 170 cd/m2 brightness from the backlight control alone is fine for working in daytime or entertainment (movies/games) anytime.

Having a panel with backlight that is stuck on high permanently (Hazro) and uses panel blocking to change brightness is idiocy in so many ways. Poor contrast, poor black, high heat, wasted power.

IMO there is no excuse for this. You don't release a product this flawed under any circumstance.
 
philjohn said:
Why? Pixel dimming will, by default, reduce the contrast ratio and produce a worse black level, which is already a weak point of IPS panels. I cannot believe that the NEC's don't have a dimmable backlight, can you provide a source please - I'm genuinely interested?
Click to expand...
Pixel dimming will, by default, reduce the contrast ratio
Click to expand...
Yes, it will. But CR is nothing. You cannot put it on bread and eat. This is abstract math, indirect, just supportive statistics.
Panel quality and depth of black - that is what you really "consume".
produce a worse black level
Click to expand...
It doesn't do anything to black level.
which is already a weak point of IPS panels
Click to expand...
???
It was 10 years ago. Modern panels have impressive 0.2 cd/m2 and even lower. 2490/2690 - outstanding in that regard.
I cannot believe that the NEC's don't have a dimmable backlight
Click to expand...
2490/2690 combine both in their OSD controls: backlight dimming and "panel dimming". There are three brightness modes - you are free to play with combinations to get what you desire. Backlight dimming reduces brightness to a particular level. Further reduction is done with "panel dimming" involved. Minimal black level (2490 ~0.19) remains with no change - whatever you do with "panel dimming".
Deep reduction of brightness by backlight only usually comes at a cost of bad backlight flickering (poor eyes!).
A bunch of popular monitors are not able to achieve acceptable brightness level at all by their backlight dimming. So "panel dimming" is used, leaving "contrast ratio" somewhere on the bottom of their packing cartons.
 
Seems like Hazro hired the wrong tech engineers for their monitors. I hear they are a small company, someone should tell them. :p
 
Sorry for finding this thread late, but I'm very interested in the HP LP2475w as a possible good gaming monitor. Has anyone done some careful input lag measurements yet, hopefully compared to a CRT?
 
Snowdog said:
Having a panel with backlight that is stuck on high permanently (Hazro)
Click to expand...

To all.
Forget this damn 26" Hazro. It's either a broken product or the reviewer has to read what he writes and think before publishing.
I would issue a good penalty point to the noob who brought that irrelevant distracting garbage to this thread.
 
X-ray Doc said:
Sorry for finding this thread late, but I'm very interested in the HP LP2475w as a possible good gaming monitor. Has anyone done some careful input lag measurements yet, hopefully compared to a CRT?
Click to expand...

They have, Browse back a few pages or check the ocuk forum that was posted with the results :rolleyes:

Anyway just wondering, on my HP status order it says

(Promotion Item) HP LP2475w Widescreen LCD Monitor KD911A4

RM2,447.00


On the website it quoted the price as RM 3056

http://h10010.www1.hp.com/wwpc/my/en/sm/WF05a/382087-382087-64283-444767-444767-3648442.html




Since it says promotion item is this the cheaper package compared to what business companies are paying for, so did i get the right one ? :confused: The part number KD911A4 was all that i could find on the HP Malaysian site.

Snowdog said:
http://www.cendirect.com/main_en/fi...W2=&rSfr=0&rSto=100000&rPar=&rCompList=&rNav=

See the Hp lp2465, lp2065, lp3065, L1745,L1750, L1950 .... etc ...

This has been discussed on numerous occasions about HPs other monitors. This is just the way they do business.

Every monitor in their "business" line has two prices. One has promotional pricing built in.

IIRC they use the higher price one on big quotes, then they negotiate a set percentage off the whole order price (which may knock it below the price of the lower one anyway). I think they do this to equalize margins on bulk purchase order, so they don't end up selling anything below cost.

No one buying an individual monitor should look at the higher price it is a business to business thing.
Click to expand...



Snowdog said:
HP has two numbers for practically every monitor. One has the "promotional" price built in. I think the other one they sell to corporations in volume,so they can then give them a discount. All rather pointless. But the two numbers mean nothing.
Click to expand...

DrRetina said:
There are two model numbers for this screen.

Try to open the link here and here.
Only difference in the URL's is the last number is 0 and 1.

The modelnumbers are KD911AT and KD911A4, and the specs are 100% identical.

Only difference on the website is "Buy online from an HP preferred partner" and "Find a local partner"
Maybe HP has different modelnumber for different sales channels?
Click to expand...





By the way the HP DreamColor LP2480zx Professional Display seem to have a internal lut :D wish i had the money for it.
Click to expand...
 
albovin said:

To all.
Forget this damn 26" Hazro. It's either a broken product or the reviewer has to read what he writes and think before publishing.
I would issue a good penalty point to the noob who brought that irrelevant distracting garbage to this thread.
Click to expand...

apologies if you dont want to talk about it, but i find it quite an interesting topic, so thanks for your input so far. Can i pick your brains about it a little more please? :)

So the NEC models do adjust "brightness" in the OSD menu as a combination of both backlight dimming (actually reducing dc voltage to the CCFL's to lower output) and digital "panel blocking" / backlight regulation or whatever one might want to call it? I notice that "backlight control" is listed as a feature for the 3090WQXi for instance at some places, so that model must have it. Do many screens actually offer backlight control, or is it mostly done using digital white / black level adjustment from the OSD contrast and brightness controls? (if you know)

on a note about the review, to be fair there is just a table showing the various luminance, black point and contrast ratio readings recorded as the OSD brightness control was altered from 100 to 0. There isn't a conclusion as such or explanation about panel dimming, CCFL dimming, whether Hazro have done some stupid or not. it just gives the results (which people have picked up on it seems).
 
Practically all panels have the brightness control as a direct backlight control.

I have owned 5 panels, all of them behaved this way, including the NEC 2490. The brightness control never controls panel blocking with the brightness control. If you want to do panel dimming, you have to dig into the menus and find "low brightness mode"

Only cheap junk and design mistakes controls panel dimming with the brightness control.

The NEC 3090 is something of an exception. It first controls backlight and when it hits minimum, it will start panel blocking, but the control changes color to let you know that it is happening.
 
trza2k said:
Where did you purchase from? Cheapest i've found in Aus is AUD $1,032 (ex tax wholesale) but currently has no stock.
Click to expand...
I don't think anyone has them in stock, they'll always say 10 days. Which was exactly the time I got mine in.

Got mine from IT national which wasn't the cheapest, but service was good.

Basically I didn't trust any of the random online retailers for something this expensive. So I phoned up HP looking for a reseller and they pointed me to IT national (which turned out to be an online reseller anyway :p).

I was really hoping for a big business like Harvey Norman, but it turned out great anyway. Willing to spend an extra $50 for peace of mind :p
 
I asked hp and they forwarded me to a reseller who was only selling 2465 ............ i got fedup so i asked HP again to buy from directly instead. This time they finally said their selling the 2475 Anyway my cc has been cleared so they said i have to wait for the freight forwarding company and for the standard turn around time to schedule delivery will be 14 working days.

:X im counting down the seconds...


My thoughts about the purchasing experience.

Their website updated the price and have a look for reseller to buy from. The link to buy is useless since their manually asking you to look for the reseller which may or may not have stock of it.

Also their online shop wasn't update selling the 2475 .....

Alternatively i tried calling direct sales but they had no clue about the 2475. They just say they aren't selling it :confused:

I then mailed before sales enquiries and you can select either buy direct from hp or buy from reseller. Anyway i finally select hp and they finally quoted the actual 2475 i was looking for.

Imho they need a little more communication between the departments so that all depts know when 2475 is being sold and availability rather then oh not being sold when in fact they are ......... :eek:
 
A quick note on my initial impressions...

Everything about this monitor is great, expect for:
- Stand is too deep, as in, you end up being too close to the screen, especially if ur desk isnt huge.
- Having quite a serious problem with the input selection

360 and comp, both on DVI (tested both ports, doesn't matter which one)

When I turn on my comp it works fine, then I switch to 360, then back to comp...

No input detected...

I have to restart my computer to have its input re-detected.

This might just be limited to the Analogue and Digital detection in DVI, so I'll have to buy a HDMI cable and test that port later.

This only happens with my comp's digital connection and not the 360's analogue.

But quite a serious problem.... a little concerned right now
 
ShadowFusion said:
A quick note on my initial impressions...

Everything about this monitor is great, expect for:
- Stand is too deep, as in, you end up being too close to the screen, especially if ur desk isnt huge.
- Having quite a serious problem with the input selection

360 and comp, both on DVI (tested both ports, doesn't matter which one)

When I turn on my comp it works fine, then I switch to 360, then back to comp...

No input detected...

I have to restart my computer to have its input re-detected.

This might just be limited to the Analogue and Digital detection in DVI, so I'll have to buy a HDMI cable and test that port later.

This only happens with my comp's digital connection and not the 360's analogue.

But quite a serious problem.... a little concerned right now
Click to expand...

Get a PlayStation 3 seriously .... Analog is a crap input anyways.

I have a PS3 at home so i will test if the switching between PS3 and the pc works or not. I will use a HDMI to HDMi cable for the PS3 and a dvi cable for my pc.

I will also try the PS3 using HDMI to DVI since i got that cable as well :eek:

1-14 days for my monitor to arrive :(
 
I've done lots of testing and I think everyone else is in the clear, its just my computer.

Done simultaneously (got 2 360s):

360 (HDMI->DVI [digital])
360 (VGA->DVI [analogue]) works fine

comp (DVI->DVI [digital])
comp (VGA->DVI [analogue]) Digital not available after changing input

The thing is it worked fine changing input on my Dell WFP2007, and its the same setup.

Anyone have any ideas :confused:

Is this the monitors fault or my comps!?

Thanks!

Moogle Stiltzkin said:
Get a PlayStation 3 seriously ....
Click to expand...
Not a chance, but lets not go there :p
 
ShadowFusion said:
A quick note on my initial impressions...

Everything about this monitor is great, expect for:
- Stand is too deep, as in, you end up being too close to the screen, especially if ur desk isnt huge.
- Having quite a serious problem with the input selection

360 and comp, both on DVI (tested both ports, doesn't matter which one)

When I turn on my comp it works fine, then I switch to 360, then back to comp...

No input detected...

I have to restart my computer to have its input re-detected.

This might just be limited to the Analogue and Digital detection in DVI, so I'll have to buy a HDMI cable and test that port later.

This only happens with my comp's digital connection and not the 360's analogue.

But quite a serious problem.... a little concerned right now
Click to expand...

Are you sure your computer just hasn't gone into "display sleep" mode. Mine does that, and all I have to do is move the mouse whilst the 2475 is detecting inputs and it finds the computer input as active again.
 
Remember the Hp Lp2475W has a software that acts like a screensaver.

Has anybody checked whether the screensaver software conflicts with windows screensaver ? Does it help disable the windows when you use the HP one instead ?
 
Shadow couple questions on the input detect problem

1. Does it matter if you do an auto detect or manual change?
2. What video card are you using?
I think I remember reading some other monitors having similar issues with one manufacturer but not the other, can't remember which though
 
I just got off the phone with HP, my order has been sitting for a few days as status "Backordered". The customer service rep didn't have an ETA on when this status would change but is going to research and call me back.

Anyone else in the US get this monitor yet?
 
ShadowFusion said:
A grand Australian dollars
Click to expand...

So, Monopoly money? ;)

ShadowFusion said:
- Stand is too deep, as in, you end up being too close to the screen, especially if ur desk isnt huge.
Click to expand...

VESA mount though, right? I have enough stands and arms around here I can deal with that as long as it's not like those artsy Samsung units without a proper mount.

hektorrr said:
Can anybody confirm for sure the HP LP2475W got S-IPS not H-IPS? Cause according http://www.tftcentral.co.uk/search.php?query=&select=model its H-IPS and according to http://h10010.www1.hp.com/wwpc/uk/en/sm/WF06b/382087-382087-64283-444767-444767-3648442-3726480.html its S-IPS.
Click to expand...

In general, any x-IPS tends to get labeled as S-IPS. It's not an error, just a somewhat imprecise way to refer to the class that is well known to be often used. TFT Central is usually right, although it's not impossible for them to have bad data. It'll out as soon as someone here takes a macro shot of it, though. :D
 
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