These are variations of the TTL flash developed by Canon. They are available on some Canon camera bodies and dedicated flash units. The differences can be summarized as follows: TTL measures light reflected off the film plane during flash exposure. Once enough light has reached the film for proper exposure, the flash pulse is cut short. A-TTL uses a pre-flash and a light sensor on the flash unit to evaluate the proper illumination needed.

These are generally used by people using either the parallel port on their computer, or a special purpose i/o board. We can provide cabling for either case.

When using advanced interface (you have a checkbox in your preference panel), SOA and TTL will be modifiable.

If you're using a modifier that goes over the main flash head (filters, Sto-Fen Omnibounce, etc.), note that the preflash in direct mode comes from the IR sensor below the main flash head. This can confuse the A-TTL programme since the IR preflash will not be filtered, giving inaccurate results. By tilting the head up slightly, or using something to release the bouncelatch, the 420EZ/430EZ will assume you are bouncing the flash and will fire the preflash through the main head.

The A-TTL sensor, being in the flash and not in the camera may yield bad apertures if filters are being used over the lens. In this case, you'll have to find some way to put a similar filter over the sensor.

The torrent's Time To Live, in hours. It means the torrent will be deleted from the tracker after that many hours have elapsed Note that this a maximum value, the torrent may be deleted at any time if it's inactive.

here we have a new 'type' of torrents, which have their time to live for ever, and that is until mod or sysop deletes them. otherwise no timelimits specified. usually it will be a mix by one of our featured djs, or it can be a very popular torrent, which was so in-demand, that sysop decides to let it live longer. if you really fill your torrent deserves to live forever - let us know.

DNS records are cached on the Internet DNS servers after the IP address is found. TTL is the amount of time that a DNS record for a host will remain in the cache of a DNS server after it has found the IP address of that host or server. The TTL on the Smart DNS server can be adjusted through the user interface.

MTU stands for Maximum Transfer Unit. RWIN for Receive Window and TTL for Time to Live .Details are available in the documentation provided with the program.

For normal operation, it's no big deal; it will cause your packets to bounce around locally a bit more than necessary, but that's a local decision. However, the impact of a high TTL can be far more significant in long-range networking. During periods of network flakiness (which seem to be happening at an ever-increasing rate), a high TTL can cause the packet to bounce around far more than necessary.

The sensor on the flash is required for A-TTL metering. That's when the 430 EZ emits a preflash, checks the return signal with its own sensor, and then computes an aperture that will work. It's best to think of the A-TTL preflash/sensor combination as a kind of reflected light flash meter built into the flash itself (and it's supposedly quite accurate too). By blocking the sensor, the A-TTL program will definitely get confused.

When you are using the TTL Hot Shoe Adaptor 2 with the Off-Camera Shoe Adaptor, you lose A-TTL. The A-TTL assumes the flash is in the camerashoe, or at least near it. It can be wildly inaccurate when far off camera, so it is disabled when using the off-camera TTL accessories. There is also the problem of multiple flashes returning conflicting information on the data bus. [Again, I don't know how flash exposure compensation is affected by this.

From Chuck Westfall: During A-TTL or TTL flash photography with the EOS-1, ambient light is measured by the peripheral metering pattern regardless of the user-selected metering pattern, including center-weighted average metering selected by CF8. RMA

The Multicast TTL (which is specified on the cache_host line of your multicast group) determines how ''far'' your ICP queries will go. In the Mbone, there is a certain TTL threshold defined for each network interface or tunnel. A multicast packet's TTL must be larger than the defined TTL for that packet to be forwarded across that link. For example, the mrouted manual page recommends: 32 for links that separate sites within an organization.

TTL stands for Time To Live. All IP packets have a TTL field and as IP packets get passed around the Internet, this TTL value is decreased, usually by one at every hop. If this field ever gets down to zero, the IP packet is discarded and does not reach its destination. What this means to you is that if you ever try to connect to a site on the Internet that is at a hop level greater than your TTL, your connection will fail.

You can get them on-line pretty easily. Digikey has a nice selection of readers Personally I have 2 readers, both from Omron's V3A Family of readers. I will try and post a larger list of on-line stores later. Until then. I recommend calling Omron and other OEMs and asking them for a list of distributors. Both the V3A and V3B family of readers are exactly the same physically. The V3A family is white or cream colored, while the V3B family is black.

In order be able to make short-term changes, the TTLs should be adjusted rather short. 30 or 60 seconds seem to be appropriate values.

TTL settings allow you to control how long objects stay in your cache. They should be set according to object type to maximise the efficiency of your cache. Hypertext (.html) objects should have a low TTL while most others can be set higher. If you do not use TTL settings, pages may become outdated in the cache. Your customers will realise this and reload pages in order to ensure they have up-to-date data, defeating the purpose of having a cache.

If we assume that A-TTL requires a separate sensor, then there are a few reasons that Canon may choose to avoid putting the sensor in the body itself: Cost: Including an extra sensor would incur an extra cost on every body manufactured. This could make Canon's bodies marginally less competitive. This is especially true if the majority of Canon owners do not wind up using A-TTL.