What is the maximum length for HDMI cables?

[Norman Willis]

Here is Canon’s response.

**

Dear Nazarene Israel:

Thank you for writing to us. We value you as a Canon customer and
appreciate the opportunity to assist you.

The 12 minute limit is imposed by the buffer (filling up), not the
memory card or HDMI out.

You should be able to use an HDMI cable of up to 158 meters before you have to boost the signal.

Please let us know if we can be of any further assistance with your EOS 5D.

Thank you for choosing Canon.

Sincerely,

Richard
Technical Support Representative

I really appreciate the fact that Canon gets back to one so quickly.

It sounds like the 12 minute limit exists regardless of the target. I wrote him back to confirm.

Norman

[Norman Willis]

I mean, I wrote him back to ask if the 12 minute limit exists independent of whether the target is internal or external flash card, or HDMI OUT. I guess still camera circuitry might work differently than video camera circuitry?

Also, does anyone have experience with maximum HDMI cable lengths?

[Brian Louis]

Usually the max length with high quality cable is 100′, longer runs like 150′ have built-in digital Signal Boosters

[Norman Willis]

Hi Brian.

How well do those Cat 5e signal extenders work?

https://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=4389487&sku=M501-4022

Is there any degradation of signal due to conversion/compression of the signal to Cat 5e, and then reconversion/decompression back to HDMI?

Or am I just asking for signal degradation with these?

Norman

[Norman Willis]

Cool. Thank you very much.

Gefen sells an ‘HDMI Super Booster Cable’ up to 150′.

https://www.gefen.com/kvm/dcable.jsp?prod_id=5736

Quote “Only cables up to 100′ will support HDMI 1.3 at 1080p.”

Quote “The 125 and 150 foot cables will support HDMI 1.2 at 1080p.”

So it looks like I could get a 50′ run for sure without signal loss?

And I can probably get a 100′ run without appreciable loss?

[Bob Zelin]

Hi Norman –
this is a very good question. I have never tried this particular unit, but at the InfoComm show in Orlando, there were at least 20 companies selling HDMI extenders just like this, that used 2 CAT 5e cables for the extention, and were all inexpensive. So at this price, I would definately try it. These are all probably made by one company in China, with different company names stamped on them.

So, try it, and let us know how it works. I bet it works just fine.

Bob Zelin

[Norman Willis]

Hi Bob.

>>So at this price, I would definately try it. These are all probably made by one company in China, with different company names stamped on them.

Funny. And you are probably right.

>>So, try it, and let us know how it works. I bet it works just fine.

I would, but now that I think about it, the boxes I saw need 110V on either end in order to make them work. I won’t have that in some of the locations I am looking to film (outdoors) and will barely have one 110V stand for the workstation. So I guess I am looking at the ‘Super (Duper) Booster Cables’ instead.

https://www.gefen.com/kvm/dcable.jsp?prod_id=5736

I can let you know how those work, if I end up going that route. As of last night I am trying to forestall all purchases for two months, just in case I might be able to get my hands on a nanoFlash unit instead, or in case the Canon EOS 5D comes out with a new model that does not have a 12 minute capture limit.

Thanks for your good thoughts.

Norman Willis
http://www.nazareneisrael.org

Dedicated System
Dell T3400
Q9650 CoreDuo Quad 3.0
8GB RAM + 4GB ReadyBoost RAM
Vista 64 Ultimate
BFG GTX260 OC Edition
C: Two 250GB WD Caviar 7200 RAID 0
D: Two 1TB Seagate Barracuda 7200 RAID 0
All backups external

[Brian Louis]

I never tried the cat5 extenders, I use a 50′ cable and I know someone who uses a 75′ with no problems, I don’t know about the 100′ but the Co. below has a 100′ which they claim shouldn’t be a problem.
https://www.abccables.com/home-theater-hdmi-cables.html

[Norman Willis]

I guess what they were saying was that if one goes too far, then the signal degrades from 1080p to 1080i. I am not at all sure how I would know if the signal degraded from p to i (i.e., I am not at all sure how I would know if my cable was ‘too long’ for my signal, and was not working for me). Is that something I could detect with my eye?

[Brian Louis]

What they are implying is the bandwidth capabilities deteriorate the longer the cable, 1080p is a much higher bandwidth than 1080i