Showing posts from September, 2022

LG 32DL655H review: input lag, deinterlacing and upscaling using the piLagTesterPRO

This 720p TV from 2012 is the most mediocre TV ever, with variable input lag, aliasing, and in general very little to recommend it for gaming, retro or otherwise.

Image quality

Good upscaling is critical for retro gaming. Ideally, all pixels should appear equally sharp and bright (no aliasing), and angled lines should appear smooth, with no jagged, irregular steps. Also important is that the display shows most or all of the pixels it is sent. Often, this is not the case, with some number of pixels cropped from the bottom or top edges. Shockingly, these tests are relevant for modern gaming as well, because even at their native resolution many TVs have aliasing and cropping.


480p/i 480i cropped but decent upscaling A-480p cropped with noticeable softness AND ringing, noticeably less good than 480i, but no aliasing. B-
720pbad aliasing at 720p (supposed native) but no cropping if selecting just scan. Allowing cropping does not improve the aliasing, just changes it. Seems to have an "intelligent" upscaler which converts 1-pxiel wide lines gray blur some of the time but not always. C+
1080pAlthough above the native resolution this actually looks a bit better than 720p.
I attempted to adjust the set to minimize cropping and aliasing.

The display has 2 HDMI ports. I neglected to check if it has more as it's such a terrible TV. Likewise I'm not bothering to upload a photo of it's upscaling results. 

Input Lag

I used a piLagTesterPRO to measure input lag. This device sends a frame of video over HDMI and measures how long it takes to display it. This display does not have a game mode; just a game 'color' preset that does not impact lag at all. I toggled all the display quality settings and did not see a consistent effect on lag, however the tests reported are with every "enhancement" set to off.

Complicating things significantly, this is yet another display that does not actually sync refresh to the input signal - instead it fills its own internal frame buffer from the video input and then draws that with an additional delay that is randomly determined each time you turn on the set or switch inputs, and slowly changes over time.  Take one example, input lag for 720p can vary from 28.4ms to 43.0ms. What you get seems to be entirely up to chance. It can't even properly synchronize the display of this buffer with the refresh rate of the input: it drifts out of sync every 10 seconds or so and has to drop or double a frame, no matter what the input refresh rate (60 or 59.94). Who knows what actual refresh rate this junk uses.

I've elected to report the average lag values here, since that seems fairest, but there's no right answer; for more discussion of this issue see the above link. It's worth noting however, that this kind of changing lag is the hardest for your brain/hands to adapt to. I'd much rather have an extra 16ms of fixed lag added to the display than one like this where sometimes the extra lag is 0, and sometimes it's 16ms.


Input Lag Test Results

I report two kinds of values. 1st response measures how long it takes for the TV to start responding (I use a 5% change in display brightness). This overly optimistic value doesn't tell how long it takes to see anything useful, but matches what other reviewers call input lag. full response is a more realistic measure of lag, and requires the display to reach 80% of full brightness. This combines both input lag and response time, and is closer to what you would actually experience in a game.

top bottom
Resolution 1st resp. min 1st resp. (average) full response 1st response full response
480i 74.8 81.8 90.8 96.8 105.8
480p 28 35.0 44.0 50.0 59.0
720p 28 35.0 44.0 50.0 59.0
1080p 28 35.0 44.0 50.0 59.0

The 1st response min column shows the lowest lag measured over several minutes, but as discussed above this is far from typical and so instead all the rest of the columns refer to the average lag. 

ALSO: That's some really slow deinterlacing. At least the response time is reasonable, at 9ms.

Results compared to other displays

To allow quick comparison between many displays I've summarized the results across all the displays I've personally tested with the piLagTester Pro. Min lag is the time to the first response, measured where the screen starts drawing (typically, the top); real lag is the time to the full response, measured where drawing finishes (usually the screen bottom), i.e. input lag + scan out + response time. Numbers in red denote average values that can vary by up to 8ms between power cycles.

DisplayYear made (TV?)Native Resnative min lagnative real lag480i real lag480p real lag720p real lag1080p real lagnative response timenative scan out
Dell E198FPb20081024p2.720.439.035.05.0012.70
Planar PLN220020211080p2.422.624.123.322.922.85.0015.17
Samsung 2494sw20111080p2.822.726.526.526.58.0013.30
Vizio VO370M20101080p2.523.683.
Dell S199WFP2009900p3.624.228.527.827.327.18.0012.60
Dell E228WFP20101050p3.024.226.526.75.0016.90
LG W1953T2010768p2.625.628.728.710.0013.00
Dell U2410 (game)20101080p4.
TCL 40S32520211080p6.527.360.629.027.927.76.0014.83
TCL 49s40320184k6.130.276.830.930.330.78.0016.13
AOC/Envision G19LWK2010900p3.131.239.538.738.437.815.5012.60
Dell E2211H20141080p3.033.634.734.534.133.815.0015.57
Panasonic TH-58PE75U2008720p28.
Dell 1907FPc20081024p3.034.035.934.815.0016.00
Panasonic TH-42PX75U2008720p28.
Panasonic TH-50PZ80U2008720p28.
Corprit D157 (hdmi)20211080p3.134.534.934.834.633.916.2515.13
Samsung S27C23020141080p2.936.036.636.136.118.1014.97
Vizio E470VL (vga)20111080p22.
Samsung LN32D4032012720p20.941.258.942.440.740.75.5014.83
Dell U2410 (sRGB)20101080p20.542.862.445.
ACER AT326520121080p19.543.862.745.343.843.88.0016.27
sony XBR 43X800D20174k24.544.346.546.044.644.75.0014.83
Element elst5016s20171080p21.445.163.546.445.145.38.0015.73
RCA L40FHD4120101080p20.346.665.
Sony 40VL130 (game)20081080p22.847.366.349.047.347.39.0815.43
Polaroid FLM-373B2007720p28.
Philips 42PFL3603D/F720091080p29.
Sony KDL-40V300020081080p22.250.168.450.650.549.811.0016.93
LG 42LC2D2006720p28.350.654.650.850.46.3015.95
GPX TDE3245W2016720p28.051.0102.
Sony KDL-46EX40020101080p28.
Toshiba 40L2200U20141080p30.
Vizio E261VA2012720p19.359.061.160.459.258.925.0014.67
LG 32DL655H2012720p35.059.0105.859.
Emprex HD 32022007720p27.066.0126.
Samsung LN32B3602010720p37.660.062.161.860.560.18.0014.40
Vizio VO22L FHDTV10A2008720p28.
Vizio E261VA2007720p28.
Samsung P2570HD20101080p37.
Sharp LC-C3234U2009720p33.064.683.666.664.615.0016.60
Samsung LN46B61020121080p53.
LG 42PT35020121080p63.567.785.968.967.767.74.200.00
Mitsubishi LT-4614420081080p51.
Toshiba 46L5200U20131080p55.
Sony 40S20L12007720p48.472.090.172.973.49.6014.00
Samsung LN46C63020121080p54.572.190.790.388.572.310.007.63
SANYO DP507492010720p67.075.0103.
Samsung HP-T425420111080p69.775.794.
LG 47LW6500-UA20121080p66.680.7149.7149.081.780.92.2711.83
Vizio E470VL (hdmi)20111080p69.086.0128.
Vizio xvt4735v20111080p67.688.688.889.288.688.69.0012.00

This list is sorted by real lag for each display's native resolution and max refresh rate (usually 1080p60 but some sets are 720p60, and other monitors support > 60hz). As you can see you have to scroll way down to find TVs as bad as this one and that's not even considering the variable lag issues. 


This would be a poor choice for gaming of any type. It's fine as a TV watching TV shows or movies though.

Email me


Email *

Message *