Question: We just upgraded our digital SLR to a Canon Digital Rebel T2i. It uses SDHC memory cards with Class 6 being recommended, especially for video use. All we have are Class 4 SDHC cards left over from the prior digital SLR. Do you think it is OK to use them?

K.K. and A.K.
Venetia

Answer: As you probably know, the SDHC Class rating refers to the card's read/write speed. Processing video, especially high-quality video from a large sensor camera like the Rebel T2i, takes up a lot of memory space and requires a lot of data to be crammed on the card as you record video. That's why the Class 6 cards are recommended. They are significantly faster than the Class 4 cards, which are pretty speedy to begin with.

You can use your Class 4 cards with your camera for still photographs, and they will work just fine. If you plan on doing video you really should use Class 6 cards or even Class 10 cards. I did some research on the subject, and it seems that there are a few Rebel T2i users who are able to record video on their Class 4 cards, but there are a lot more who ran into trouble when trying to do so. What's more, certain brands seem to work better than others, with some users reporting problems with Class 6 cards from budget brands. Sandisk was reported to be very reliable, and Lexar cards are always a good choice as well.

When you start using your new camera, be sure to format all your memory cards, both new and old. After you insert the card, go into the setup menus and find the format command. Formatting will erase the memory card and set it up for optimum operation for your make and model of camera. Just be careful because formatting erases everything on the card, including photographs you locked with the protect command.

Question: We have two TVs. On one television, we have a Comcast HD converter box. On the other, a Sony KV-20FS120 tube TV, there isn't a Comcast HD converter, and so do not get the HD channels on that television.

Is there a way to get the HD channels on the second television without having to pay Comcast for a second HD converter box?

NEAL ROTH
McMurray

Answer: Your TV does not have a digital tuner so at the least you would need an HDTV tuner. By tuner I mean a full-fledged HDTV tuner, not a $60 converter boxes, and HDTV tuners are getting expensive and hard to find since all TVs have them built-in now.

Even with the tuner you would only be able to get free local HDTV channels, whether you got them from Comcast's feed or an antenna. Comcast used to broadcast the local digital stations for free on the coaxial cable, but I do not know if they still do so. Everyone I know with Comcast got switched to converter boxes (some against their will) and lost their free HDTV as a result. Your best bet is to get another TV with a built-in tuner and try it with your cable line. If it does not work, get an antenna to receive free local HDTV.

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