Equipment Review No. 2  June 2001
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Silicon Image Iscan Pro Line doubler/upconverter
SRP $900
Silicon Image, Inc.
1060 E. Arques
Sunnyvale, CA 94085
408-616-4000 (voice)
408-830-9530 (fax)


Description and Specifications: Possible uses include: HD (digital ready) televisions, progressive scan and multimedia televisions, data projectors, plasma televisions, and computer monitors. Unit converts 480I (Standard Definition) signals to 480P (higher definition progressive) signals. Works with PAL/ NTSC/ SECAM. Motion-adaptive video deinterlacing; works with film sources, computer graphics, and video; 3:2 pulldown, diagonal processing; 10-bit DACS; adaptive 2D comb filter; s-video, composite, and component input with auto sensing and switching; 15-pin VGA-type output with RGB or component output; picture controls (brightness, contrast, color, tint, sharpness); normal or squeeze aspect ratio; external power supply. 8.3" L x 5.8" W x 1.4" H. 1 year warranty.

Equipment Used: Barco 808, Toshiba M754 VCR, Comprehensive 5' and 25' VGA-5 BNC cable, PS Audio P600 power generator, Marantz PD-4292D plasma television, Nakamichi Soundspace 11 DVD changer, Monster Video 2 component, M500V S-video, Audioquest VSD-1, Toshiba CW34X92, Toshiba TW65X81, Nakamichi DVD-10, Toshiba SD6200, Audioquest YIQ1, Marantz DV7100, Marantz PV5580W, Echostar 6000.

Setup/ Operation:

I.TV compatibility. The first and most important thing regarding the Iscan's operation is to make sure it will work with your television! If your TV is not HD ready then most likely it will not work. There is a TV compatibility chart on the Silicon Image web site located at Another question that may come to mind is why use an external doubler when almost every HD ready TV has its own doubler built in? The simple answer is: better performance. Also, if you own a data projector then most likely you do NOT have a doubler built in, and need something to upconvert the image in order to improve brightness and make scan lines much less visible. For those who own 7" gun (or larger) projectors with a scan rate that supports higher than 31.5 kHz, then a tripler or scaler is recommended over a device such as the Iscan.

II.Types of cables. It will be necessary to determine what type of connection is on your display device. On my projector it was necessary to use 5 BNC cables, so I used a VGA-BNC cable. The other options would be a VGA-VGA cable, or as in the latter part of the review, I used 3 BNC-RCA plugs and converted the VGA-BNC cable for use with the Toshiba and Marantz televisions having 3 RCA type inputs. In this configuration it will be necessary to flip the switch on the front of the Iscan for proper operation. And lastly, for those who have devices that require composite sync, or sync on green (and you know who you are), then it will be necessary to change some jumpers inside the Iscan. This procedure is detailed in the manual.

III.Input connections. As noted in the Description, there is only one of each type of video input (composite, S-video, component) on the Iscan. If you have more than one device that uses the same type of input, then a video switching device will be necessary. Most surround receivers/ preamps offer some kind of video switching capability; otherwise an outboard video switcher will be necessary.

IV.Automatic Input Selection and Priority inputs. The Iscan automatically looks for an active video signal and begins from the component to the s-video and then to the composite video. If a device is to be constantly on, and you want to set the Iscan Pro to check for a different input, then you can set the priority switch to that input.

V.Aspect ratio control and the Squeeze Mode. This function is strictly for use with Widescreen televisions. If the television does not have a way to change the aspect ratio to allow for a 1.33:1 image to fit within the larger width of the Widescreen set, then the squeeze mode will allow this to occur. UNFORTUNATELY, if you have a Widescreen set that automatically expands images to fill the full width of the set, and DVD's that are in a wide format but are NOT enhanced for Widescreen sets (aka not anamorphic), then you will not be able to get them to fill the screen and be in the correct aspect ratio. This is more of a fault of the television, but there are probably at least a few people who would buy this device in a second if it had some sort of expansion circuit to fit the letterboxed movie into the 1.78:1 frame of the widscreen set. Are you listening Silicon Image? Of course, many would say that most DVD's these days are Widescreen enhanced, but that does not help with all the others that are not.

VI.The good ole gray bar vs. black bar debate. The Iscan offers a choice of either gray or black sidebars when using the squeeze mode. This is nice for a couple of reasons. For the person who owns a widescreen CRT/ Plasma device and is worried about burn-in, it is a good idea to use the gray bars in order to burn the phosphors or plasma more evenly. For DLP and LCD users, the black bars are ok. Or, for those not caring about the possibility of burn-in they can eliminate the usually very bright bars (ala Toshiba) and watch 1.33:1 material with black on the side. (This only applies to a non-progressive/ HD signal on the Toshiba).

VII.The Manual. The manual is very helpful and has not only a complete troubleshooting section, but pictures for hookup and suggestions on the best ways to hook up the Iscan. Also, there are 2 pages devoted to explanation on how TV works and how the Iscan Pro will enhance the performance in a typical system.

VIII.Picture controls. The Iscan Pro has adjustments for color, tint, contrast, brightness, and sharpness. The sharpness and hue controls do not function with a component input. It would seem to make sense to adjust the TV set for proper color balance with this input and then adjust it differently (if necessary) for the composite/ S-video input. Being that the Iscan has only one set of adjustments, it is less flexible in terms of picture controls than televisions that have separate controls for every input. Some televisions (especially projectors) don't allow color adjustments for high scan rate inputs, so they can definitely help in this situation.

Video System #1: For the first set of tests I used the Iscan with a Marantz plasma television that has a rated resolution of 853x480. I ran the 5' VGA-BNC cable directly to the RGBHV inputs on the television. I ran the component cable from the DVD player to the component input on the plasma directly. When I wanted to change to the Iscan, I would move the component cable connected to the TV to the Iscan. I used the AVIA disc or Video Essentials to match the contrast, brightness, color, tint, and sharpness on both sources. Note: The contrast control did not seem to work like conventional contrast controls. When you turn it up it makes the picture darker. Most controls when turned up make the whites brighter. It seemed like the control was wired backwards and I never got a satisfying explanation, but it was no big deal to turn it the opposite way than I would normally when adjusting the contrast. It was probably just my sample that exhibited this behavior, but I can't be sure. Viewing distance from the plasma was approximately 6 feet.

I put on the Eagles' Hell Freezes Over DVD, and put the TV in Full mode and flipped the squeeze switch on the Iscan to set the picture to the proper 4x3 aspect ratio. Personally I don't know how people can watch 4x3 material in the dark with big gray bars on the side of the image. The word on the street is burn-in is just around the corner, but I say burn baby, burn. I won't recommend you watch with the bars off, but I did. With the Iscan, picture definition was better and colors appeared a tad more vibrant. Jagged lines on the guitar were apparent with the Iscan or direct from the DVD player. There was also a better sense of depth to the image and background and foreground seemed to separate. For some reason there seemed to be more video noise and the image was slightly fuzzier without the Iscan in the system.

Next up was the Dances With Wolves clip from DTS Sampler #4. Without the Iscan connected, the people and objects had more of an outline around them like the sharpness control was turned up. The image looked more like video (tape that is) than film. In the part of the scene where a rope is next to a horse, the rope appears jagged without the Iscan, but was smooth and looked more accurate with the Iscan in the system. Overall the image was subtly easier on the eye and more natural looking.

Two things come to mind in this setup. The first is that the Marantz has some of the best video processing (scaling) built in of any of the plasma sets I've seen, and yet the Iscan made the image subjectively better. With a cheaper set the improvements would no doubt be even more obvious and worthwhile. The second has to do with changing inputs on the television. Some TVs have direct input selection so they can be programmed via macro into learning remote controls. In other words, when you select a certain video source the remote will change inputs on the TV accordingly. However, some TV's make this difficult or almost impossible. And for anyone who is tired of constantly changing the input on the television each time they go from DVD (component) to satellite (S-video) and then to VCR (composite), this will solve that problem. Set the priority input on the Iscan and each time you turn on the appropriate component for viewing, the Iscan will select it and output it to the TV. The only thing you may have to change is the aspect ratio that would either mean another button on the TV or a switch on the front panel of the Iscan. I guess we are a long way from an easy solution for all the different video formats.


Video System #2: System 2 consisted of the Nakamichi DVD-10 and the Toshiba CW34X92 34" direct view set. For this test I tried using an S-video and composite connection from the DVD player as well as the component connection. In System #1 I used component exclusively. This disabled the sharpness and hue adjustments. While adjusting the picture controls on the Iscan, I noticed a couple of interesting things. When turning the sharpness down, the image began to blur and ghost severely. It was as if the image doubled as soon as the control was turned down. When it was turned up it had the usual effect of halos forming around objects. The television has SVM (Scan Velocity Modulation) and it could have been reacting strangely to the changed sharpness, but I don't really know. The controls themselves are small knobs that turn smoothly but seem to act like stepped controls as far as the effects visually. They are hard to adjust just right and except for the center position are hard to keep track of. It would have been much nicer to have a button with some kind of indicator (either on the front panel or on-screen) to help set the controls. Or even have a few preset settings!

I put on chapters 7-10 from Starship Troopers and went back and forth several times. With the DVD player feeding the Iscan with an S-video cable vs. an S-video cable into the TV, the Iscan looked better, had less interlace artifacts, looked less digital, and had a softer, smoother look to it. There were occasional jagged edges present with either the Iscan or direct into the TV. With the component connection the image was more colorful, had better depth, and looked more natural. The differences were less with the better connection. This just goes to show you should always use the best connection available for every source. I also compared the image from the Iscan with the S-video and the composite connection from the DVD player. Either I was tired or there wasn't a big difference. I used a few moving patterns in AVIA and film as well, but didn't see huge differences. Normally I'd expect much more dot crawl or other artifacts caused by the DVD player's circuitry changing the signal to composite. In either case, you'd definitely want to use the component connections from the DVD player.


Video System #3: Next I moved onto a progressive scan DVD player vs. the Iscan. The Marantz PV5080W rear projection set was used along with a Marantz DV7100 DVD player. Unfortunately I didn't have a VGA-VGA cable that was long enough of any kind of quality. This meant going behind the set and changing connections each time I wanted to make a comparison. This made making a good comparison difficult. With the Marantz there are no gray bars, period! Instead a 4x3 image inset in the 16x9 screen moves left and right slowly. In any case I only used Widescreen material with this set of testing. On chapter 4 from Pink Floyd's The Wall, I noted a few less jagged lines along with some softening of the video image. If I had to choose I would probably go for the slighter sharper image of the DVD player directly in this case. This was confirmed when I put on chapter 14 from A Thin Red Line. Again, the image had a bit more jaggedness to it without the Iscan, but also appeared to have better color saturation.


Video System #4: Another rear projection set by Toshiba, the TW65X81, was used along with the Toshiba SD6200 and Echostar (Dish Network) 6000 Receiver for System 4. In this system there was a clear preference for the progressive scan DVD player vs. the Iscan. Of course the interlaced image used for the Iscan was fed out of the same player, so with another player the tables may have been turned, but I was unable to try this. With chapter 2 from The Messenger, the SD6200 looked sharper and had better color definition and depth. These are the same advantages observed when the interlaced output is fed directly into the Toshiba TV vs. the progressive output fed directly into the TV. With chapter 5 from the Eagles' Hell Freezes Over the video looked softer with the Iscan, and jagged lines were present with both players. Perhaps a proper comparison would be with a player that sources their progressive circuitry from Silicon Image.

The Echostar 6000 satellite receiver offers component, S, composite, and RF outputs. The component output with SD (standard definition) material is typically worse looking than the output with an S-video connection into the TW65X81. So I compared the S-video connection into the Iscan vs. directly into the television. With channel 144 (an espn channel) there was a boxing match on. The image was more digital looking without the Iscan. On channel 300 (HBO) Galaxy Quest was playing and the image was smoother and more natural with the Iscan in the system. Lastly I viewed channel 690 (iSHOP). With the Iscan the image was far better on this channel. Without the Iscan the image had shiny white digital artifacts in bright sections all over the picture. When the image was moving, the Iscan had the most profound effect.

I spent some time experimenting between setting the TV to Full and the Iscan to squeeze, and vice versa. In the end I suppose it would be worth experimenting with assuming your TV allows aspect ratio adjustment with progressive images. I was unable to use the gray bars with the satellite image on the squeeze mode because there was a thin black line to the left of the image that was easily noticeable and even more distracting than the gray bars themselves! The satellite source provided the most obvious benefits with the Iscan. I'm sure some will find its value alone in this application.


Video System #5: This system utilized the Barco front projector along with the Toshiba VCR. These days there are only a few devices that would use a composite video connection. Even video game systems seem to offer at least S-video. Laserdisc, VCR, and possibly cable TV would be candidates for connection to this input. I can connect the VCR directly to the projector but the image is rather dim and I just see a bunch of scan lines. This projector really needs an image with a much higher line rate.

I connected the VCR to the Iscan and was having some difficulty getting a picture, but it was due to a bad connection on the back of the VCR. Once this was fixed the image came right up and the projector locked onto the signal. I watched a couple of videotapes and they looked much better than with a direct connection to the projector. The truth is that the picture was still dim and I could see scan lines. I decided to watch the first half hour of Serial Mom. I didn't notice any motion artifacts, and overall the image was pretty good considering the source. I played around with the controls on the front of the Iscan to subjectively improve the image. I was able to get a very viewable image, but if I were serious about watching a composite source I would be looking for a unit with a higher line rate. With a 7" projector or a smaller rear projection set this would not likely be a big issue, if one at all. I should mention that the image is approximately 110" in a 4x3 aspect ratio from the projector.

Conclusion: Minus the few shortcomings and/or limitations mentioned in the review, the Silicon Image Iscan Pro is an impressive piece of equipment. I should note that the Iscan's performance would be dependent on not only the display device used, but the source component as well. I was only able to use it with a few modest priced DVD players. With higher performance players (or just different units) the results obtained may vary. In short, the differences wrought by the Iscan were the most noticeable with the lowest quality sources. It appears that the processing in the various display devices give less improvement with poor source material. If your prime viewing material consists of standard definition satellite, cable, laserdisc, videotape, or videogames (which weren't tried so I'm just extrapolating) then I would suggest you check out the Iscan Pro. It is compact, well made, simple to set up, and does everything it is supposed to do with aplomb.

- Brian Bloom

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