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Ease of Use
Intended Use:
Mobile Presentation
Optoma ML550 Projector Optoma ML550
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10000:1 Contrast Ratio
500 Lumens
PC 3D Ready
$479 Street Price
$799 MSRP

Optoma ML550
Portable LED Projector

Marc Davidson, December 16, 2013

Setting up the Projector

Good Connectivity. The ML550's back panel offers just a few connectors, but they're all you need.

  • 1 HDMI, MHL enabled, so it can work with, for example, a Roku stick for streaming video.
  • 1 proprietary I/O port paired with an adaptor that plugs into the port on one end and combines a 42" cable ending in a VGA connector for a computer with a 6" cable ending in a female mini-jack for audio output.
  • 1 MicroSD card slot
  • 1 USB A (For a USB memory key, a $99 optional Wi-Fi dongle, or direct connection to a PC to upload files to memory. Free Wi-Fi apps are available for Windows, Mac, iOS, and Android OSs.)

    Setting up. One minor setup issue is that if you want to show files directly from the projector's 1.5GB internal memory, you need a USB A to USB A cable to transfer the files. Optoma doesn't include one, however, so you need to buy one separately if you want to take advantage of the feature. You may also want to get the optional $20 tripod or $99 Wi-Fi dongle.

    The vertical offset for the ML550 lines up the bottom of the image with the center of the lens. This is ideal if you're using a table-top screen on the same table as the projector. If you need to adjust the image position and don't have the tripod, however, you can either use the screw adjustment on the projector's front foot to raise the image, or simply rest the front or back of the projector on something to change the image height. You can then square off the image with the manual keystone control.

    Setup is otherwise simple, with the focus tab offering just enough resistance for sure control. There's no zoom, however, so you have to move the projector to adjust image size. For an extended session in moderate ambient light, I settled on a 48" diagonal image, with the projector just over 6' from the screen.

    As with any projector this light, the ML550 tends to pivot if there's any tension on the cables plugged into it. I usually solve that problem for testing by taping the cable down. However, putting something on the cable, like a paper weight, works just as well.

Previous Page
The Viewing Experience
Next Page
Key Features and Testing
Review Contents: Introduction The Viewing Experience Setup Key Features and Testing
  Limitations and Conclusion

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Comments (7) Post a Comment
Tony Posted Dec 17, 2013 10:54 AM PST
Why would you buy the ML550 when for $100 more you could buy the ML750?
frank Posted Dec 28, 2013 3:21 AM PST
price quotation and conditions of transportation
Jeff Posted Dec 30, 2013 5:33 AM PST
If the ML550 is the projector you are saying I am getting for $100 more than projector X to get 500 Lumen (and any of the other features) over the 300 or 400 lumen projector you were originally looking at.

You can keep saying well, this one is only $X more....
Nabi Posted Jan 10, 2014 5:30 PM PST
You've got to watch the claims of long LED lamp life. It's more than a bit of a scam: over time the lamp gets dimmer and dimmer. On my Acer unit a note popped up on the screen at around 2000 hours advising that it would no longer produce the light necessary for bright mode and suggesting lamp replacement. It was impossible to get hold of Acer to make my complaint. The performance of that projector is now increasingly wishy-washy so I'd suggest you view LED projectors as primarily good for portability particularly as more conventional projectors have lamps that last over 4000 hours now.
JD55555 Posted Feb 24, 2015 2:45 AM PST
Have a problem with my Optoma ML550. The projector work great when directly connected to different sources with HDMI - roku, HTPC, PS2, chromecast. However, when an HDMI switch is used, no video is displayed by the projector. A TV connected with the same cables, works perfectly. I've tried 3 different HDMI switches, including a powered J-Tech "matrix" one. I've swapped all the HDMI cables and tested with the projector AND the TV. TV works, projector doesn't.

It is not an HDCP issue - I've seen the "non-compliant hardware" warning from the roku connected to a computer monitor. That isn't it.

Swapping the HDMI cable to use another device is getting old.

Does anyone have an HDMI switch that actually works with the Optoma ML550 projector?
xxx Posted Nov 15, 2016 4:46 PM PST
Does anyone know if this projector reads subtitles files ( .srt)?? Thanks in advance
Ron Posted Nov 19, 2016 9:56 AM PST
These are cross-branded... ACER seems to be the originator - it's identical to the K series... in this case a K135. Acer spec's theirs at 600 lumens, but other than that, it's the same beat... different skin. Look at all of the physical aspects... connectors, card slot, IR sensor, cooling openings, lens, etc. I have the K132 which is why I recognized it.

It would be interesting to know who actually makes these... when I mod'd my Acer (to get direct audio output), I saw no names internally.

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