Optoma HD25 1080p Full HD 3D DLP Projector Review

When Optoma released their HD33 1080p 3D projector back at the end of 2011, there was very little in the way of competition. As a result, Optoma's entry level 3D projector set a new benchmark in terms of price point and performance, picking up a Best Buy award, when we reviewed it here. However, 18 months later the market place is very different with a number of manufacturers releasing 1080p 3D projectors in the sub-£1,000 price bracket. At just £795 the HD25 certainly hits the spot when it comes to price but with so much competition around, Optoma is going to need more up its sleeve if it wants to go toe-to-toe with the likes of BenQ. The HD25 is a single-chip DLP projector, with a resolution of 1920 x 1080 and full 3D capability; it also has a claimed brightness of 2,000 ANSI lumens, 2 HDMI v1.4a inputs and a built-in 10W speaker. All fairly standard at this price point these days but perhaps more unusually the HD25 also has a colour management system, something that the more expensive HD33 didn't have. Given that the HD25 also comes with a pair of glasses and emitter, this sounds like a very attractive package. Let's find out just how attractive...

The HD25 uses the kind of utilitarian chassis that is fairly typical of the cheaper end of the projector market. Many of these projectors recycle the same chassis design used for projectors aimed at the data grade market and, as such, have inherited many of the same features. So you get an all-white chassis, with an offset lens, plenty of ventilation grilles and built-in 10W speakers that you will almost certainly never use. The HD25 incorporates similar sporting curves to those found on the HD33, which at least helps differentiate it from its less home cinema orientated brethren. The use of a white chassis probably won't be an issue if you plan on using the HD25 in a normal living room with white walls or a white ceiling. However if you would rather have a black chassis, Optoma also make the HD131X, which appears to have exactly the same specifications as the HD25. The build quality and styling are rather plastic in nature but despite this, the HD25 does have a surprisingly solid construction. The chassis measures 324 x 234 x 97mm and weighs 3.1kg, so at least mounting on the ceiling should be easy. There are some basic controls at the top rear of the chassis, in case you lose the remote, and all the connections are situated at the rear.

There are adjustable feet under the chassis for tilting the projector when it is mounted on a table or shelf. There is a large air intake on the right hand side and corresponding exhausts at the front and on the left, out of which hot air vents when the projector is in use. The HD25 is fairly noisy, with the fans being audible during very quiet passages in films but it isn't any nosier than the competition. There is a fair amount of light spill from the air vents however and whilst this won't be an issue if the projector is behind you or up on the ceiling, it is worth bearing in mind if the HD25 is table mounted in front of you. Given the HD25's relatively limited throw ratio (1.5 - 1.8), it is quite possible that the projector will be positioned in front of you, unless you are using a very small room. As is common with the majority of Optoma's projectors, the lens is off-centre on the right hand side of the chassis and above the lens mount there is a manual zoom control and the lens mount itself can be rotated manually to focus the image. The HD25 doesn't have any lens shift and this, coupled with the narrow throw range and off-set lens, means that positioning the HD25 correctly is essential for an effective installation of the projector.

The HD25 has an interesting set of connections, including two HDMI inputs (v1.4a for full 3D support) and a composite video input using a RCA connector. The projector's data grade ancestry is revealed by the presence of two VGA inputs and a VGA output, along with analogue audio in and out connectors. There is also a RS232 connector for system control, a 3D-Sync Out (3-Pin VESA) connector for the RF 3D emitter and a USB port for firmware updates. In addition, the HD25 comes with a three pin power cord that connects at the rear of the chassis. We found that our review sample was somewhat temperamental when it came to HDMI handshaking and sometimes the HD25 couldn't detect the attached device. In addition the projector could be a little slow at handshaking and sometimes it showed an hourglass, which was actually more annoying.

The accompanying remote control is small, comfortable to hold and includes backlighting. At the bottom are buttons for directly selecting the inputs (HDMI1, HDMI2, VGA1, VGA2 or Video) which is preferable to cycling through a single input button. The middle of the remote control comprises of the navigation and enter buttons and, at the bottom left of the navigation buttons, is the menu button. We found this to be a slightly annoying location for the menu button, which was hard to find in the dark, even with backlighting. We would recommend moving the input buttons further down the remote control to allow for a bigger menu button directly below the navigation buttons. Above the navigation controls there are buttons for direct access to selections such as Native, LBX and 3D Format, as well as key controls like Brightness, Contrast and Lamp Mode. Finally, at the top of the remote control are the on and off buttons. There is no dedicated button for turning on the backlight which means you need to know the location of the button you initially want to press when using the remote control in the dark.

The HD25 ships with one pair of glasses and the emitter, more glasses can be picked up for about £70. The RF sync emitter is very small and since it doesn't use infra-red and thus doesn't need line-of-sight, it can be placed anywhere. The range of the RF emitter is big enough for even the largest room and we never once had a problem with a loss of sync. The RF glasses themselves are rechargeable and can be turned on by pressing a small button on the top of the left hand arm, a LED light flashes once to indicate the glasses are ready for 3D use. The glasses themselves are black with reasonably large lenses, which is good because it provides a wide field of view, and a soft rubber nose piece and they fit comfortably over normal glasses. They also have very wide sides which is excellent for blocking out ambient light. Our only complaint would be that the lenses are very dark which seemed to rob the 3D images of some of their impact.

The HD25 uses a simplified menu system compared to some of Optoma's other home cinema projectors and as such it consists of only four primary menu pages. The first is Display, where you will find the controls for selecting the format (4:3, 16:9, LBX, Native, Auto, Superwide), with native the best choice for high definition content. There is also a control for masking the edges of the image and another for zooming (scaling) it. In addition there are controls for shifting the image vertically or horizontally, as well as for vertical keystone adjustment. Finally there is a 3D menu where you can select some basic 3D controls including 3D Mode, 3D to 2D, 3D Format and 3D Sync Invert.

The second menu screen is Setup and this relates to selecting the language, projection position, the menu location, the audio settings, the security features and the projector ID. The third menu relates to Options and includes controls for selecting the input source, as well as the source lock. There is a high altitude option, a control for hiding the information screen, a keypad lock, test patterns and a control for the IR function.

The final menu page is Image and as the name suggests it includes all the calibration controls for picture accuracy. Here you can select the Display Mode, with a choice of Cinema/Reference/Photo/Bright/3D/User, although if you make any changes the mode automatically defaults to User. There are also the standard controls for Brightness, Contrast, Sharpness, Colour and Tint.

Within the Advanced sub-menu there are controls for noise reduction, selecting the appropriate gamma curve (Film/Video/Graphics/Standard), the BrilliantColor feature and the dynamic black control (Off/Low/High). You can also select the colour temperature (Warm/Medium/Cold), the colour space (Auto/RGB (0-255)/RGB (16-235)/YUV) and the colour settings.

Unusually for a projector at this price point, the Colour Settings menu provides access to a colour management system where you can adjust the hue, saturation and gain (luminance) of the three primary colours (red, green and blue) and the three secondary colours (cyan, magenta and yellow). There is also a control for adjusting white, which acts as a basic white balance control, allowing you to adjust the amount of red, green or blue in the entire greyscale.

The HD35 actually delivered a rather impressive performance when it came to 2D, creating bright and accurate images that had plenty of impact. There are certain areas where a single-chip DLP projector is strong and one of them is in terms of the sharpness of the image. Thanks to the use of a single chip, the HD25 delivered some very detailed images, despite the use of a cheap lens array. Another area of strength is in terms of motion handling, with smooth camera pans that were free of smearing or loss of detail. Finally, although the absolute blacks might not be as good as some other projection technologies, the ability to reproduce blacks within the frame and maintain shadow detail can be quite effective, even in very dark scenes. The HD25 also had plenty of brightness, allowing it to light up a reasonably big screen, whilst still retaining plenty of punch.

All of these factors, combined with the accurate greyscale and colour gamut, certainly benefited whatever content we were watching although the HD25 obviously performed best with high definition material. Here the detailed and bright images were coupled with wonderful motion handling, especially with 24p discs to deliver some great pictures. Recent Blu-ray purchases like Zero Dark Thirty and Les Miserables looked great on the HD25 and we often found ourselves forgetting how cheap it is - relatively speaking. Whilst blacks may not be inky, there was detail in the shadows and the images always felt as though they had sufficient dynamic range. Colours also looked natural and the whites were free of any unwanted discolouration, resulting in a very pleasing 2D performance.

Of course the HD25 isn't perfect and the rather average deinterlacing and scaling meant that standard definition content didn't look as impressive, nor did some 1080i content, where the occasional deinterlacing artefact was apparent. The big problem with single-chip DLP projectors is the use of a colour wheel which can cause rainbow artefacts that some people are susceptible to; there's nothing you can do, it's a limitation of the technology but it is worth bearing in mind. The other problem, which we mentioned earlier, is that the HD25 can be rather noisy and is certainly louder than the 26dB that Optoma claim. However we have yet to hear a budget projector that was quiet, they are all bright and, as such, run hot so you're always going to get a lot of fan noise.

The other area where DLP projectors have a definite edge is in terms of their 3D performance where, thanks to their faster response times, they can deliver images that are free of [tip=crosstalk]crosstalk[/tip]. This proved to be the case with the HD25 and yet, despite the relative accuracy of the 3D Display Mode and the potential brightness of the projected image, we found ourselves slightly underwhelmed. Quite why this was we weren't entirely sure but it might well be due to Optoma's glasses, which have very dark lenses. It seemed to us that the lenses on the glasses were robbing the 3D image of some of its brightness and thus its potential impact. There was nothing wrong with the 3D, the images were accurate and detailed, there was plenty of depth, the motion handling was great and there was absolutely no crosstalk but for some reason recent purchases like Life of Pi and Wreck It Ralph just weren't wowing us the way they had on other projectors. You also need to make sure you select VESA 3D rather than the default DLP-Link setting in the 3D menu, otherwise you get inverted 3D images. Apparently there has been a firmware update to address a bug where the HD25 kept defaulting to DLP-Link whenever it was turned off but we didn't have any such issues on our review sample.

When you first turn the HD25 on you have a choice of four Display Modes - Cinema, Bright, Photo and Reference. Interestingly Optoma claim that the Cinema mode is for home theatre use but they also claim that the Reference mode is designed to reproduce as closely as possible to the tip=IndStand]industry standards[/tip]. That sounds like the one for us but we did measure both Cinema and Reference to see which was the most accurate and it turned out to Reference. If you change any of the settings, the HD25 immediately defaults to User, so all we could do was select the Reference Display Mode for the out-of-the-box measurements. We also selected the Native Picture Format with high definition content to ensure the image wasn't being scaled.

As you can see from the top left graph, the [tip=Greyscale]greyscale[/tip] performance of the HD25 in the Reference Display Mode was actually very good for an out-of-the-box setting. All three primary colours are tracking close to each other, although there is a slight lack of red. However the overall [tip=DeltaE]DeltaEs[/tip] (errors) are all less than three, which is the tolerance level for the human eye, meaning that these errors are too small to really see without a direct comparison. Aside from a slight dip at 90 [tip=IRE]IRE[/tip], the [tip=gamma]gamma curve[/tip] is also tracking our target of 2.2 very closely. The [tip=gamut]colour gamut[/tip] wasn't quite as accurate, although the [tip=cie]CIE Chart[/tip] above right does show that the [tip=Colortemp]colour temperature[/tip] is at [tip=D65]D65[/tip], which reflects the accurate greyscale. There is a clear over-saturation in the colour of green, which in turn is causing an error in yellow. Conversely there is an under-saturation of blue which is causing an error in the saturation and hue of magenta. The luminance or brightness of all the colours, with the exception of blue and magenta, was underpowered, which offset some of the over-saturation.

For these measurements we used the User Display Mode and set the Brightness and Contrast correctly, whilst leaving the Colour and Tint controls at their default settings. We set the Sharpness to 9 which gave us the best results, any lower and the image was softened, any higher and there was ringing. We turned the Noise Reduction down to zero, selected a Gamma setting of Film, turn BrilliantColor down to 1 and turned the Dynamic Black feature off. We selected a Colour Temperature of Warm and a Colour Space of Auto. We then used the Colour Settings menu to access both the [tip=WhiteBal]White Balance[/tip] control and the [tip=CMS]Colour Management System[/tip] (CMS).

The HD25 doesn't have a proper two-point white balance control but within the Colour Settings sub-menu there is a basic white balance control which allows you to adjust the amounts of the primary colours across the entire greyscale, rather than at two specific points. Since the greyscale was already very accurate, all we needed to do was boost red slightly and the errors all dropped to below 1, which is essentially perfect. Whilst the gamma curve does have a slight dip at both 10 and 90 IRE, it is tracking 2.2 perfectly from 20 to 80 IRE which is the most important part of the image. Overall this is a fantastic performance from what is essentially a budget projector and a great achievement by Optoma.

We were pleased to see a colour management system on the HD25, especially as there wasn't one on the more expensive HD33 and we were even happier to discover that it worked. Not only was the CMS capable of delivering accurate colours but it also did so without introducing any unwanted picture artefacts. We found we were able to get the luminance measurements for all the colours spot on and most of the colour and hue measurements were also excellent. As a result the majority of colours were hitting their target for [tip=Rec709]Rec.709[/tip] and the overall errors were below one which is superb. The only colour we had trouble with was blue, which was under-saturated, but since it's the smallest part of the visible spectrum this under-saturation wasn’t really apparent. It also caused a slight under-saturation in magenta but again this wasn't visible with real world material.

This excellent overall colour performance also extended to the saturation sweeps, where despite the HD25's budget status and use of a colour wheel, the tracking was very impressive. There were no hideous errors lurking at 25, 50 or 75% saturation and whilst the under-saturation of blue was still in evidence, the other colours all tracked very closely to their targets. We've seen far more expensive projectors that haven't performed this well.

If there is one area where DLP projectors tend to struggle it's black levels and the HD25 was no exception. We measured the black level at 0.06 cd/m2 which might seem low but when actually viewed appears like a dark grey rather than black. Optoma claim a contrast ratio of 20,000:1 for the HD25 but once calibrated and with any dynamic contrast features turned off, it actually measures closer to 1,400:1. However on the plus side, once the brightness control was set correctly, the shadow detail was actually quite good. One area where the HD25 did perform well was in terms of brightness and even after calibration it could still easily output 1,000 lumens on a sensibly sized screen. This added brightness helped mitigate the black and create images that had a reasonable dynamic range.

The HD25 performed reasonably well in these tests and was able to fully reproduced the SMPTE colour bar tests for both PAL and NTSC, correctly scaling the full 576i and 480i images without any loss of detail or unwanted ringing. The video deinterlacing test was reasonably good, although on the motion adaptive deinterlacing test the projector introduced some jaggies. However it had no problems in resolving all the fine brickwork in the detail tests on both the PAL and NTSC discs. On the film detail test the HD25's performance was good and in the cadence tests the projector correctly detected the 3:2 (NTSC - USA/Japan) format as well as the 2:2 (PAL - European) format. The projector also had no problems displaying mixed film material with scrolling video text and was able to reproduce the text without any shredding or blurring.

The HD25 performed well in the tests using high definition content and with the player set to 1080i, the projector correctly deinterlaced and displayed both the video and film resolution tests and showed good scaling and filtering performance as well as good resolution enhancement. With 1080i material the projector had no difficulties in showing video text overlaid on film based material and also handled 24p content without any problems. The one area where the HD25 fell down was the Dynamic Range High test showing video levels above reference white (235) up to peak white (255). This test showed that the HD25 was clipping all three primary colours and white, thus losing detail above video level 235. Whilst it would be nice to be able to see all the way up to peak white, because otherwise you might lose some detail in bright whites, it isn't a problem and certainly wouldn't adversely affect the projector's overall performance.

Optoma HD25 1080p Full HD 3D DLP Projector Review