<?xml version="1.0" encoding="UTF-8" ?><rss version="2.0" xmlns:content="http://purl.org/Rss/1.0/modules/content/" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:trackback="http://madskills.com/public/xml/rss/module/trackback/"><channel><title>Vincent&#39;s life</title><link>http://www.i170.com/user/weichengyan/Rss</link><description></description><language>zh-cn</language><pubDate>Sat, 05 Jul 2008 21:04:56  +0800</pubDate><generator>i170.com</generator><image><title>Vincent&#39;s life</title><url>http://www.i170.comattavatar_1/weichengyan_Src.JPG</url><link>http://www.i170.com/user/weichengyan/Rss</link></image> <item><link>http://www.i170.com/Article/108181</link><title><![CDATA[留恋]]></title><author>weichengyan</author><category></category><pubDate>Thu, 03 Jul 2008 14:44:32  +0800</pubDate><description><![CDATA[<p align="center">昨天，是我从公司辞职后的第一天,</p>
<p align="center">忽然之间，感觉自己又回到了无业游民的行列，有些无所事事的韵味．</p>
<p align="center">于是拿起相机，出了门，漫不经心地游走于海口的大街小巷之间，想记录下些什么?</p>
<p align="center">也许是即将要离开了，对这个生活过的地方，或多或少有些留恋吧!</p>
<p align="center">&nbsp;</p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/38592e000d0db9ca3df6e820fccdcf0da5340b4a137c0700418e/0/CRW_3371.jpg"></p>
<p class="partingline">[separator]</p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/545247db352f45339dc91c86e4b44f1adf453ca5c237070080d2/0/CRW_3372.jpg"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/d8128211892a5cd093e0a85a607ae7db64bfdaccd7a507005355/0/CRW_3373.jpg"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/ea816505a9692f7f7ed1f2f61e2c5d51613d447ba3960600af7f/0/CRW_3374.jpg"></p>

]]></description><guid>http://www.i170.com/Article/108181</guid><trackback:ping>http://www.i170.com/Article/108181/trackback</trackback:ping><comments>http://www.i170.com/Article/108181#comment</comments><wfw:commentRss>http://www.i170.com/Article/108181/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/108143</link><title><![CDATA[新旧交替]]></title><author>weichengyan</author><category></category><pubDate>Wed, 02 Jul 2008 14:10:04  +0800</pubDate><description><![CDATA[<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/f896932437fd6cf40ab21ed5c6d607af8838e6e7add909009652/0/CRW_3370.jpg"></p>

]]></description><guid>http://www.i170.com/Article/108143</guid><trackback:ping>http://www.i170.com/Article/108143/trackback</trackback:ping><comments>http://www.i170.com/Article/108143#comment</comments><wfw:commentRss>http://www.i170.com/Article/108143/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107974</link><title><![CDATA[傍晚]]></title><author>weichengyan</author><category></category><pubDate>Sat, 28 Jun 2008 18:41:23  +0800</pubDate><description><![CDATA[<p align="center">生活于海口也已经有几年了，但一直都没有注意到海口的晚霞竟然有这么漂亮．</p>
<p align="center">也许是要即将离开了，才蓦然发现这片自己生活和工作过的地方，有这么多动人之处．</p>
<p align="center">&nbsp;</p>
<p align="center">日落黄昏后</p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/e258c6eb7f7c635b8f1a8284a7ef6ed088ebd5191c7d0400e283/0/CRW_3353.jpg"></p>
<p class="partingline">[separator]</p>
<p align="center">淡蓝的海水，凋零的黄花</p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/672df768e8f800a75022a6450954f3a3f6b9d9b88cbd0600618f/0/CRW_3356.jpg"></p>
<p align="center">灯光初上，却见黄花怒放．</p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/e8550d829a93f683ad936cb856e55bb2ca7ebaf519ec05008e3a/0/CRW_3358.jpg"></p>

]]></description><guid>http://www.i170.com/Article/107974</guid><trackback:ping>http://www.i170.com/Article/107974/trackback</trackback:ping><comments>http://www.i170.com/Article/107974#comment</comments><wfw:commentRss>http://www.i170.com/Article/107974/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107866</link><title><![CDATA[I miss you]]></title><author>weichengyan</author><category></category><pubDate>Thu, 26 Jun 2008 00:29:39  +0800</pubDate><description><![CDATA[<p align="center"><embed src=
"http://www.8box.cn/feed/F59090_s_93084_/mini.swf" width="160"
height="32" scale="NoScale" loop="loop" wmode="transparent"
quality="1" type="application/x-shockwave-flash"><br>
歌曲 - I Miss You<br>
演唱 - 罗百吉<br>
专辑 - 舞动人生</p>
<p class="partingline">[separator]</p>
<p align="center">这一刻是我给你最后的机会<br>
用不着对我又吼又乱叫<br>
我一定对你是真心真意<br>
这你不用来质疑</p>
<p align="center">你的背叛已经伤了我太深<br>
不知是否应不应该太认真<br>
也许你以后会改变自己<br>
但我已决定必须离开你</p>
<p align="center">I Miss You I Miss You<br>
I Miss You everyday<br>
只想看看你的脸<br>
想念你 想念你<br>
想念你的欢笑<br>
整颗心已属于你</p>
<p align="center">你的背叛已经伤了我太深<br>
不知是否应不应该太认真<br>
也许你以后会改变自己<br>
但我已决定必须离开你</p>
<p align="center">I Miss You I Miss You<br>
I Miss You everyday<br>
只想看看你的脸<br>
想念你 想念你<br>
想念你的欢笑<br>
整颗心已属于你<br>
I Miss You I Miss You</p>
<p align="center">I Miss You everyday<br>
只想看看你的脸<br>
想念你 想念你<br>
想念你的欢笑<br>
整颗心已属于你</p>
<p align="center">罗百吉：I Miss You I Miss You<br>
I Miss You everyday<br>
只想看看你的脸<br>
想念你 想念你<br>
想念你的欢笑<br>
整颗心已属于你</p>
<p align="center">让时间随着音乐流走<br>
我轻轻对你唱着这首歌<br>
I Miss You I Miss You<br>
I Miss You everyday<br>
只想看看你的脸<br>
想念你 想念你<br>
想念你的欢笑<br>
整颗心已属于你<br>
I Miss You 鸣……<br>
想念你 咿……<br>
已属于你……</p>
<p align="center">&nbsp;</p>
<p>&nbsp;</p>

]]></description><guid>http://www.i170.com/Article/107866</guid><trackback:ping>http://www.i170.com/Article/107866/trackback</trackback:ping><comments>http://www.i170.com/Article/107866#comment</comments><wfw:commentRss>http://www.i170.com/Article/107866/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107828</link><title><![CDATA[2008.6.24]]></title><author>weichengyan</author><category></category><pubDate>Wed, 25 Jun 2008 00:11:27  +0800</pubDate><description><![CDATA[<p align="center">傍晚，下班后，于回家的路上拍摄，主要目的还是景深练习．</p>
<p align="center"><embed src=
"http://m1.woyo.com/music--c6f3d40f4d48e88080b771ac200806232250283003LBUL40.mp3"
width="700" height="28" type="application/x-mplayer2" autostart=
"1"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/b8529d0a2151e470a62d8a19ec6b1eb5ace665a0d29405002a30/0/CRW_3332.jpg"></p>
<p class="partingline">[separator]</p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/4da8c6a61488ea34522c2e7af3ece4a92b085e8604480500d790/0/CRW_3334.jpg"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/3e46aec1914cc916925657115ea40887589bbbb223620600afcc/0/CRW_3335.jpg"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/086451c6eab2d49b27459b74e2cd7b7a9c65b6e343d30800eec7/0/CRW_3337.jpg"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/bc881a759b65ef7d52a0bddef5c9bf3bd530762601b10700d4a2/0/CRW_3338.jpg"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/30f141e7732c1f5a9b61b3900440ef2f07732df035e905009b10/0/CRW_3339.jpg"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/7848453d16e75b3f207804d4803f8355674488a23d8d050063a8/0/CRW_3341.jpg"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/0f8b6608d63093fede3b0d332ca159ba649db0f92f760600d2ef/0/CRW_3340.jpg"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/152edab7313f2dc19b170be9f006b098fd3f8cfb04120500fefe/0/CRW_3342.jpg"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/7f671439dfc20d2a9d95128d2b1400cda5d5c4f867ce05003c38/0/CRW_3344.jpg"></p>
<p align="center"><img alt="" align="absmiddle" src=
"http://i.namipan.com/files/75c17eccfa3403c2f5c5bc1e6a5dd44eb141609815c805000a3f/0/CRW_3345.jpg"></p>

]]></description><guid>http://www.i170.com/Article/107828</guid><trackback:ping>http://www.i170.com/Article/107828/trackback</trackback:ping><comments>http://www.i170.com/Article/107828#comment</comments><wfw:commentRss>http://www.i170.com/Article/107828/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107786</link><title><![CDATA[游戏币]]></title><author>weichengyan</author><category></category><pubDate>Tue, 24 Jun 2008 12:58:10  +0800</pubDate><description><![CDATA[<p align="center">游戏币是两个星期前和一好朋友及他的女朋友一起玩剩下的，之后就一直放在我的抽屉．</p>
<p align="center">&nbsp;</p>
<p align="center">游戏币,铅币连成直线．</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/5403f5ffe7f79378366c9af9053dfcb8483af6e562900600bb67/0/CRW_3328.jpg"></p>
<p class="partingline">[separator]</p>
<p align="center">只是拍摄的角度有些不同罢了．</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/549c2d72759a7f18fb00394c083a7da3d63583a82d6f0500aa86/0/CRW_3329.jpg"></p>
<p align="center">游戏币的反面</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/40995894b9dc5709cb7cd24f2b630cb85955dd72feee060066cd/0/CRW_3330.jpg"></p>
<p align="center">大光圈＋近摄距拍摄出来的效果，有些朦胧的感觉．</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/10b78acb0518add3dbbbeee6c3edecc748c3b3098abc0300acab/0/CRW_3331.jpg"></p>
<p align="center">&nbsp;</p>
<p>&nbsp;</p>

]]></description><guid>http://www.i170.com/Article/107786</guid><trackback:ping>http://www.i170.com/Article/107786/trackback</trackback:ping><comments>http://www.i170.com/Article/107786#comment</comments><wfw:commentRss>http://www.i170.com/Article/107786/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107727</link><title><![CDATA[蓝天白云]]></title><author>weichengyan</author><category></category><pubDate>Sun, 22 Jun 2008 21:00:38  +0800</pubDate><description><![CDATA[<p align="center">昨天的天气非常之好，于是走到海南大学校园内逛了一圈，出来的时候，在东门附近拍了几张．</p>
<p align="center">&nbsp;</p>
<p align="center">海南大学校园内的东坡湖</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/3415d29a8df4109a37f651e1a2a98178f7a770177e6f03008d48/0/CRW_3319.jpg"></p>
<p class="partingline">[separator]</p>
<p align="center">海南大学东门对面的小区</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/7891a5e6243c5bc335e7bdcb1f4b6be4636f9794aa330400aef7/0/CRW_3322.jpg"></p>
<p align="center">侨达花园，如三年前下狠买下一套的话，估计现在的价值都翻两倍了．</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/20b7f7ca909f23fe24dfb6e2e6e780e85b2b2932f61d0500c731/0/CRW_3323.jpg"></p>
<p align="center">一柱擎天</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/6ca0d2bf0dc5f9b7b3df73a42ea137a30044daa6c9bd05002b13/0/CRW_3324.jpg"></p>
<p align="center">中国银行海南省分行员工住宅楼</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/766d771a75f0ff047785c0fa3c4f9de4fa198ec58680050088be/0/CRW_3325.jpg"></p>

]]></description><guid>http://www.i170.com/Article/107727</guid><trackback:ping>http://www.i170.com/Article/107727/trackback</trackback:ping><comments>http://www.i170.com/Article/107727#comment</comments><wfw:commentRss>http://www.i170.com/Article/107727/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107705</link><title><![CDATA[景深2]]></title><author>weichengyan</author><category></category><pubDate>Sun, 22 Jun 2008 01:03:53  +0800</pubDate><description><![CDATA[<p align="center">难得的大睛天，决定出去走走，呼吸一下新鲜天气。</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/23c95ddf04fe6fb7280634dadc165c6c8a0e6677c47604005f53/0/CRW_3308.jpg"></p>
<p class="partingline">[separator]</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/cb036999ed97d7a1be163ade65be7612eb9195a1907b0300ed53/0/CRW_3310.jpg"></p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/74d31e36e90aa8253664bbf0e5543bf915b4e5b946860300a89d/0/CRW_3312.jpg"></p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/5ad3fc7fc56f1be422970baf05fc967d4312e8ec3ebc03000caf/0/CRW_3313.jpg"></p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/4fc9e2b02deed1b8c6c8c4a495e92c13f3220f8c8ffb0200299f/0/CRW_3314.jpg"></p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/d438f8a4c0829fb80625f6f06a42e64adbcccc3808200400b388/0/CRW_3317.jpg"></p>

]]></description><guid>http://www.i170.com/Article/107705</guid><trackback:ping>http://www.i170.com/Article/107705/trackback</trackback:ping><comments>http://www.i170.com/Article/107705#comment</comments><wfw:commentRss>http://www.i170.com/Article/107705/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107588</link><title><![CDATA[乌云]]></title><author>weichengyan</author><category></category><pubDate>Wed, 18 Jun 2008 20:37:07  +0800</pubDate><description><![CDATA[<p align="center">这些天一直都在下雨，但今天的整个天空布满了乌云，有些壮观。</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/dca0e4abbcd7d70bfaf77280c3d3a95843f62a4775a603008a8c/0/CRW_3301.jpg"></p>

]]></description><guid>http://www.i170.com/Article/107588</guid><trackback:ping>http://www.i170.com/Article/107588/trackback</trackback:ping><comments>http://www.i170.com/Article/107588#comment</comments><wfw:commentRss>http://www.i170.com/Article/107588/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107485</link><title><![CDATA[雨后天空]]></title><author>weichengyan</author><category></category><pubDate>Tue, 17 Jun 2008 00:15:10  +0800</pubDate><description><![CDATA[<p align="center">十点到客户那帮忙处理一些新中大银色快车SE的数据恢复问题,</p>
<p align="center">在处理这些问题期间，外面的天空不间断的下起了雨，一时间清爽了许多，</p>
<p align="center">最重要的是工作进行得很顺利，也顺便蹭了一顿饭。哈哈！</p>
<p align="center">&nbsp;</p>
<p align="center">这是吃完饭休息时拍摄的，只有一张。</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/9f4ba667c698d84156c155e8b848dca45bb82d872ed804003556/0/IMG_3300.jpg"></p>

]]></description><guid>http://www.i170.com/Article/107485</guid><trackback:ping>http://www.i170.com/Article/107485/trackback</trackback:ping><comments>http://www.i170.com/Article/107485#comment</comments><wfw:commentRss>http://www.i170.com/Article/107485/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107323</link><title><![CDATA[将要饭变成一种艺术]]></title><author>weichengyan</author><category></category><pubDate>Sat, 14 Jun 2008 00:40:24  +0800</pubDate><description><![CDATA[<p align="center"><embed src="http://www.tudou.com/v/469CZ_OrPko"
width="600" height="450" scale="ShowAll" loop="loop" menu="menu"
wmode="transparent" quality="1" type=
"application/x-shockwave-flash"></p>
<p>&nbsp;</p>

]]></description><guid>http://www.i170.com/Article/107323</guid><trackback:ping>http://www.i170.com/Article/107323/trackback</trackback:ping><comments>http://www.i170.com/Article/107323#comment</comments><wfw:commentRss>http://www.i170.com/Article/107323/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107321</link><title><![CDATA[妈咪，别哭]]></title><author>weichengyan</author><category></category><pubDate>Sat, 14 Jun 2008 00:26:55  +0800</pubDate><description><![CDATA[<p align="center"><embed src="http://www.tudou.com/v/0PCoAQhltqs"
width="600" height="450" scale="ShowAll" loop="loop" menu="menu"
wmode="transparent" quality="1" type=
"application/x-shockwave-flash"></p>
<p align="center">很感人的动画，以一个孩子的视角来诉说这段故事。</p>
<p>&nbsp;</p>

]]></description><guid>http://www.i170.com/Article/107321</guid><trackback:ping>http://www.i170.com/Article/107321/trackback</trackback:ping><comments>http://www.i170.com/Article/107321#comment</comments><wfw:commentRss>http://www.i170.com/Article/107321/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107307</link><title><![CDATA[雨天]]></title><author>weichengyan</author><category></category><pubDate>Fri, 13 Jun 2008 20:05:04  +0800</pubDate><description><![CDATA[<p align="center">六月，海南的天气就像孩子的脸，说变就变。</p>
<p align="center">今天的天气尤其如此，</p>
<p align="center">早上，烈日炎炎,晒得人浑身难受，头皮发麻。</p>
<p align="center">如果此刻能身处在空调房中，是一件很幸福的事。</p>
<p align="center">不想，到了下午的4时，</p>
<p align="center">天空中落下了雨滴，竟然稀里哗啦地下起了大雨。</p>
<p align="center">不爽，不爽。</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/60039edaf4f2ae558a9d36895ab06f527b9daf62d26005007c79/0/CRW_3299.jpg"></p>
<p class="partingline">[separator]</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/4ca84b67a79dd503c69bfd0b1c0622b0f9e042d6db9d0400668c/0/CRW_3297.jpg"></p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/4cee61793e8e4c21e021267681cc2be97cb55bae59a20400beae/0/CRW_3298.jpg"></p>
<p align="center">&nbsp;</p>
<p align="center">&nbsp;</p>

]]></description><guid>http://www.i170.com/Article/107307</guid><trackback:ping>http://www.i170.com/Article/107307/trackback</trackback:ping><comments>http://www.i170.com/Article/107307#comment</comments><wfw:commentRss>http://www.i170.com/Article/107307/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107305</link><title><![CDATA[练习]]></title><author>weichengyan</author><category></category><pubDate>Fri, 13 Jun 2008 18:45:55  +0800</pubDate><description><![CDATA[<p align="center">练习景深，于是拿了我的破烂blackberry手机当对象。哈哈！</p>
<p align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/80b2da778df457b47b9c454dfaf0948b87686235fc8a03001a49/0/CRW_3296.jpg"></p>

]]></description><guid>http://www.i170.com/Article/107305</guid><trackback:ping>http://www.i170.com/Article/107305/trackback</trackback:ping><comments>http://www.i170.com/Article/107305#comment</comments><wfw:commentRss>http://www.i170.com/Article/107305/commentRss</wfw:commentRss></item> <item><link>http://www.i170.com/Article/107270</link><title><![CDATA[景深概念与计算]]></title><author>weichengyan</author><category>影技</category><pubDate>Thu, 12 Jun 2008 22:46:08  +0800</pubDate><description><![CDATA[<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center">先介绍几个概念：</p>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center"><font color=
"#FF0000"><strong>1、焦点(focus)</strong></font></p>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center">
与光轴平行的光线射入凸透镜时，理想的镜头应该是所有的光线聚集在一点后，再以锥状的扩散开来，这个聚集所有光线的一点，就叫做焦点。</p>
<div align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/f0ecbc11e986f96a9c316f5bbd344a66de66b3ae4a2200001cac/0/focuspoint.gif"></div>
<p class="partingline" align="center">[separator]</p>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center"><font color="#FF0000"><strong>2、弥散圆(circle of
confusion)</strong></font></p>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center">在焦点前后，光线开始聚集和扩散，点的影象变成模糊的，形成一个扩大的圆，这个圆就叫做弥散圆。</p>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center">
在现实当中，观赏拍摄的影象是以某种方式(比如投影、放大成照片等等)来观察的，人的肉眼所感受到的影象与放大倍率、投影距离及观看距离有很大的关系，如果弥散圆的直径小于人眼的鉴别能力，在一定范围内实际影象产生的模糊是不能辨认的。这个不能辨认的弥散圆就称为容许弥散圆(permissible
circle of confusion)。</p>
<div align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/883243748e487c6a5a5eec8c017c3e787f15813568240000f37a/0/circle-cunf.gif"></div>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center">不同的厂家、不同的胶片面积都有不同的容许弥散圆直径的数值定义。一般常用的是：</p>
<div align="center">
<table cellspacing="0" cellpadding="0" border="1">
<tbody>
<tr>
<td class="ts1" nowrap="nowrap" align="center" bgcolor="#000080">
<p style="margin: 3px 10px; text-indent: 0px; line-height: 120%">
<font color="#FFFFFF">画幅</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="center">
<p style="margin: 3px 10px; text-indent: 0px; line-height: 120%">
<font color="#000080">24mm x 36mm</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="center">
<p style="margin: 3px 10px; text-indent: 0px; line-height: 120%">
<font color="#000080">6cm x 9cm</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="center">
<p style="margin: 3px 10px; text-indent: 0px; line-height: 120%">
<font color="#000080">4" x 5"</font></p>
</td>
</tr>
<tr>
<td class="ts1" nowrap="nowrap" align="center" bgcolor="#000080">
<p style="margin: 3px 10px; text-indent: 0px; line-height: 120%">
<font color="#FFFFFF">弥散圆直径</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="center">
<p style="margin: 3px 10px; text-indent: 0px; line-height: 120%">
<font color="#800000">0.035mm</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="center">
<p style="margin: 3px 10px; text-indent: 0px; line-height: 120%">
<font color="#800000">0.0817mm</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="center">
<p style="margin: 3px 10px; text-indent: 0px; line-height: 120%">
<font color="#800000">0.146mm</font></p>
</td>
</tr>
</tbody>
</table>
</div>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center">
35mm照相镜头的容许弥散圆，大约是底片对角线长度的1/1000~1/1500左右。前提是画面放大为5x7英寸的照片，观察距离为25~30cm。</p>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center"><strong><font color="#FF0000">3、景深(depth of
field)</font></strong></p>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center">
在焦点前后各有一个容许弥散圆，这两个弥散圆之间的距离就叫景深，即：在被摄主体(对焦点)前后，其影像仍然有一段清晰范围的，就是<font color="#FF0000"><strong>景深</strong></font>。换言之，被摄体的前后纵深，呈现在底片面的影象模糊度，都在容许弥散圆的限定范围内。</p>
<div align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/d9cf1ee6dedcea63f196ece09c7e43b481b0a4391c3a00006814/0/depth1.gif"></div>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center">景深随镜头的焦距、光圈值、拍摄距离而变化。对于固定焦距和拍摄距离，使用光圈越小，景深越大。</p>
<div align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/80ddd9aceb05e5bb289128ad8158bfbb9f73a8adf4320000d83b/0/depth2.gif"></div>
<p align="center">&nbsp;</p>
<p><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/bdde0034064c66630c534edd626ec0d1fca0a6f5aa5800002d36/0/depth-1.gif"></p>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center">以持照相机拍摄者为基准，从焦点到近处容许弥散圆的的距离叫前景深，从焦点到远方容许弥散圆的距离叫后景深。</p>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center"><font color="#FF0000"><strong>4、景深的计算</strong></font></p>
<p class="MsoNormal" style=
"margin: 10px 0px; text-indent: 30px; line-height: 120%" align=
"center">下面是景深的计算公式。其中：</p>
<div align="center">
<table cellspacing="0" cellpadding="0" border="0">
<tbody>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
<font color="#800080">δ</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;——</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;容许弥散圆直径</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
<font color="#800080">f</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;——</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;镜头焦距</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
<font color="#800080">F</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;——</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;镜头的拍摄光圈值</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
<font color="#800080">L</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;——</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;对焦距离</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
<font color="#800080">ΔL1</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;——</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;前景深</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
<font color="#800080">ΔL2</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;——</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;后景深</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
<font color="#800080">ΔL</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;——</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
&nbsp;景深</p>
</td>
</tr>
</tbody>
</table>
</div>
<div align="center">从公式(1)和(2)可以看出，<font color=
"#800080"><strong>后景深 &gt; 前景深</strong></font>。</div>
<div align="center">
由景深计算公式可以看出，景深与镜头使用光圈、镜头焦距、拍摄距离以及对像质的要求(表现为对容许弥散圆的大小)有关。这些主要因素对景深的影响如下(假定其他的条件都不改变)：</div>
<div align="center"><font color="#FF00FF">(1)、镜头光圈：</font></div>
<div align="center"><font color=
"#FF00FF">光圈越大，景深越小；光圈越小，景深越大；</font></div>
<div align="center"><font color="#FF00FF">(2)、镜头焦距</font></div>
<div align="center"><font color=
"#FF00FF">镜头焦距越长，景深越小；焦距越短，景深越大；</font></div>
<div align="center"><font color="#FF00FF">(3)、拍摄距离</font></div>
<div align="center"><font color=
"#FF00FF">距离越远，景深越大；距离越近，景深越小。</font></div>
<div align="center"><strong><font color=
"#FF0000">5、一些计算实例</font></strong></div>
<div align="center">网上有些在线计算器，有兴趣的网友可以参考：</div>
<div align="center"><a href=
"http://211.99.196.232/cgi-bin/pgc/test/formular.cgi"><strong><u><font color="#0000FF">
摄影光学计算器</font></u></strong></a></div>
<div align="center">Windows版本的可下载的计数器在</div>
<div align="center"><a href=
"http://www.cameraunion.net/download/fcalc.htm"><strong><u><font color="#0000FF">
f/Calc</font></u></strong></a></div>
<div align="center"><font color=
"#0000FF">(1)、200/2.8对焦在5m时，f/2.8的景深：</font></div>
<div align="center">
<table cellspacing="0" cellpadding="0" border="0">
<tbody>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">δ</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;0.035mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">f</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;200mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">F</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;2.8</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">L</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;5000mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">ΔL1</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;60mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">ΔL2</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;62mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">ΔL</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;122mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF0000">结论</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF0000">：</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color=
"#FF0000">&nbsp;该镜头在用f/2.8拍摄时，清晰范围是从4.94m~5.062m，景深很浅。</font></p>
</td>
</tr>
</tbody>
</table>
</div>
<div align="center"><font color=
"#0000FF">(2)、200/2.8+2X=400/5.6对焦在5m时，f/5.6的景深：</font></div>
<div align="center">
<table cellspacing="0" cellpadding="0" border="0">
<tbody>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">δ</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;0.035mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">f</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;400mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">F</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;5.6</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">L</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;5000mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">ΔL1</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;30mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">ΔL2</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;31mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#FF00FF">ΔL</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">=</p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;61mm</p>
</td>
</tr>
<tr>
<td class="ts1" align="center">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
<font color="#FF0000">结论</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
<font color="#FF0000">：</font></p>
</td>
<td class="ts1">
<p style="margin: 3px 5px; text-indent: 0px; line-height: 120%">
<font color=
"#FF0000">&nbsp;该镜头在配合2X增距镜后，主镜头用f/2.8拍摄时，景深是(1)的一半。</font></p>
</td>
</tr>
</tbody>
</table>
</div>
<div align="center"><strong><font color="#FF0000">&lt;next
page&gt;</font></strong></div>
<div align="center"><strong><font color=
"#FF0000">景深的实际拍摄照片</font></strong></div>
<div align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/ace35750ec757c2778a6603d00675f812427eed463a0010024fe/0/f11.jpg"></div>
<div align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/e7101bcb7876f6022d0b908ed0cb1c7d610024b005b901007e59/0/f22.jpg"></div>
<div align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/00a5572d180a0c867bb707cd3b9fffc41b7eeadb454f01008de8/0/f28.jpg"></div>
<div align="center"><img align="absmiddle" alt="" src=
"http://i.namipan.com/files/4c6d23ea54f93fa0527940741f7d0d77d8ae7d80c9850100795e/0/f56.jpg"></div>
<div align="center">&nbsp;</div>
<div align="center"><a href=
"http://www.cameraunion.net/book/optical/depthoffield.htm">http://www.cameraunion.net/book/optical/depthoffield.htm</a></div>
<div align="center">
<table cellpadding="0" width="70%" border="1">
<tbody>
<tr>
<td>
<div align="left">
<table cellspacing="0" cellpadding="0" border="0">
<tbody>
<tr>
<td class="ts1" nowrap="nowrap" height="18">
<p class="MsoNormal" style=
"margin: 0px 5px; text-indent: 0px; line-height: 120%" align=
"center">&nbsp;</p>
</td>
<td class="ts1" nowrap="nowrap" align="center" height="18">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#000080">FδL<sup>2</sup></font></p>
</td>
<td class="ts1" nowrap="nowrap" align="right" height="18">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;</p>
</td>
</tr>
<tr>
<td class="ts1" nowrap="nowrap" height="18">
<p class="MsoNormal" style=
"margin: 0px 5px; text-indent: 0px; line-height: 120%" align=
"center"><font color="#000080">前景深 ΔL1=&nbsp;</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="center" height="18">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#000080"><span style=
"letter-spacing: 0px">——————</span></font></p>
</td>
<td class="ts1" nowrap="nowrap" align="right" height="18">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color=
"#000080">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&nbsp;&nbsp; &nbsp;&nbsp; (1)</font></p>
</td>
</tr>
<tr>
<td class="ts1" nowrap="nowrap" height="18">
<p class="MsoNormal" style=
"margin: 0px 5px; text-indent: 0px; line-height: 120%" align=
"center">&nbsp;</p>
</td>
<td class="ts1" nowrap="nowrap" align="center" height="18">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%"
align="center"><font color="#000080">f<sup>2</sup> + FδL</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="right" height="18">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%"
align="center">&nbsp;</p>
</td>
</tr>
</tbody>
</table>
</div>
</td>
</tr>
<tr>
<td>
<div align="center">
<table cellspacing="0" cellpadding="0" border="0">
<tbody>
<tr>
<td class="ts1" nowrap="nowrap" height="18">
<p class="MsoNormal" style=
"margin: 0px 5px; text-indent: 0px; line-height: 120%" align=
"left">&nbsp;</p>
</td>
<td class="ts1" nowrap="nowrap" align="center" height="18">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
<font color="#000080">FδL<sup>2</sup></font></p>
</td>
<td class="ts1" nowrap="nowrap" align="right" height="18">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
&nbsp;</p>
</td>
</tr>
<tr>
<td class="ts1" nowrap="nowrap" height="16">
<p class="MsoNormal" style=
"margin: 0px 5px; text-indent: 0px; line-height: 120%" align=
"left"><font color="#000080">后景深 ΔL2=&nbsp;</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="center" height="16">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
<font color="#000080">——————</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="right" height="16">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
<font color=
"#000080">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
(2)</font></p>
</td>
</tr>
<tr>
<td class="ts1" nowrap="nowrap" height="17">
<p class="MsoNormal" style=
"margin: 0px 5px; text-indent: 0px; line-height: 120%" align=
"left">&nbsp;</p>
</td>
<td class="ts1" nowrap="nowrap" align="center" height="17">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
<font color="#000080">f<sup>2</sup> - FδL</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="right" height="17">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
&nbsp;</p>
</td>
</tr>
</tbody>
</table>
</div>
</td>
</tr>
<tr>
<td>
<center>
<table>
<tbody>
<tr>
<td class="ts1" nowrap="nowrap" width="101" height="18">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
<font color="#000080">ΔL2 + ΔL2&nbsp;&nbsp;=&nbsp;</font></p>
</td>
<td class="ts1" nowrap="nowrap" align="center" width="82" height=
"18">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
<font color="#000080">——————</font></p>
</td>
</tr>
<tr>
<td class="ts1" nowrap="nowrap" width="87" height="19">
<p class="MsoNormal" style=
"margin: 0px 5px; text-indent: 0px; line-height: 120%" align=
"left">&nbsp;</p>
</td>
<td class="ts1" nowrap="nowrap" width="101" height="19">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
&nbsp;</p>
</td>
<td class="ts1" nowrap="nowrap" align="center" width="82" height=
"19">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
<font color="#000080">f<sup>4</sup> -
F<sup>2</sup>δ<sup>2</sup>L<sup>2</sup></font></p>
</td>
</tr>
</tbody>
</table>
</center>
<div align="center">
<table cellspacing="0" cellpadding="0" width="276" border="0">
<tbody>
<tr>
<td class="ts1" nowrap="nowrap" width="87" height="19">
<p class="MsoNormal" style=
"margin: 0px 5px; text-indent: 0px; line-height: 120%" align=
"left">&nbsp;</p>
</td>
<td class="ts1" nowrap="nowrap" width="101" height="19">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
&nbsp;</p>
</td>
<td class="ts1" nowrap="nowrap" align="center" width="82" height=
"19">
<p style="margin: 0px 5px; text-indent: 0px; line-height: 120%">
<font color="#000080">2f<sup>2</sup>FδL<sup>2</sup></font></p>
</td>
</tr>
<tr>
<td class="ts1" nowrap="nowrap" width="87" height="18">
<p class="MsoNormal" style=
"margin: 0px 5px; text-indent: 0px; line-height: 120%" align=
"right"><font color="#000080">&nbsp; 景深 ΔL =&nbsp;&nbsp;</font></p>
</td>
</tr>
</tbody>
</table>
</div>
</td>
</tr>
</tbody>
</table>
</div>

]]></description><guid>http://www.i170.com/Article/107270</guid><trackback:ping>http://www.i170.com/Article/107270/trackback</trackback:ping><comments>http://www.i170.com/Article/107270#comment</comments><wfw:commentRss>http://www.i170.com/Article/107270/commentRss</wfw:commentRss></item> </channel></rss> 