{"id":575,"date":"2007-09-17T18:05:01","date_gmt":"2007-09-17T09:05:01","guid":{"rendered":"https:\/\/regex.info\/blog\/2007-09-17\/575"},"modified":"2007-12-18T23:34:01","modified_gmt":"2007-12-18T14:34:01","slug":"tripod-stability-tests-part-i","status":"publish","type":"post","link":"https:\/\/regex.info\/blog\/2007-09-17\/575","title":{"rendered":"Tripod Stability Tests, Part I"},"content":{"rendered":"\n\n

(Note: this post will be of interest only to camera geeks)<\/b><\/p>\n\n

My previous post contained a superficial listing of considerations for\nbuilding a tripod<\/span><\/a>, and\nleft off wondering how to test the effect of various ways to use a tripod.<\/span>\nFor example, how detrimental is it to add a center<\/span> column? How beneficial<\/span> is mirror lock\nup<\/a>? Since getting my really nice tripod<\/a>, I find myself<\/span> wanting to learn how to use it properly, and these questions are a\nbig<\/span> part of that.<\/p>\n\n

I tend to dive into things looking for answers, as evidenced by the posts in my photography-tech category<\/a>, such as\nmy auto-focus test chart<\/a>,\nmy\nanalysis of NEF compression<\/a>,\nmy seven-page writeup on\ndigital-image color spaces<\/a>,\nor\nmy Lightroom metadata-panel presets builder<\/a>. In this case<\/span>, I'm not really<\/span> sure how to proceed,\nbut I've come up with some tests and results that at least form a basis<\/span> for further study.<\/p>\n\n

I'm not really sure how relevant the test I'm about to present are, both\nin theory and in how I executed<\/span> them. One of the<\/span> reasons for my writing\nthis post is to solicit comments on the validity of my methodology and\ninterpretation.<\/p>\n\n

The Tests<\/p>\n\n

I created a simple test-pattern image, shown here at quarter size (click to see the full-sized version):<\/p>\n\n

<\/a><\/div>\n\n

I set up my tripod at one end of the longest hallway in my home, and\ndisplayed the test pattern on my laptop's<\/a>\nscreen at the other end 16m (53 feet) away. I mounted<\/span> the big Nikkor\n70<\/span>-200 f\/2.8<\/a> onto my D200. My goal was<\/span> to get something that had bulk\nto challenge the tripod support system, and also reach (high magnification)\nto exaggerate the effects of any instability. (Frankly, a 200mm<\/span> lens is not\nreally very much magnification, but it's the best that I have<\/span> at hand.)<\/p>\n\n

To give you an idea of what I am testing with, here's a picture<\/span> from my tripod post<\/a> showing the\ncamera and lens mounted on my ballhead.<\/p>\n\n

<\/a>\nKodak DX6490 — 1<\/sup>\/<\/big>500 sec, f\/4.5, ISO 80 —\nfull exif<\/a><\/span>\n<\/div>\n\n

I took dozens and dozens of one-second test exposures under various\nconditions. (See this post<\/a> for a discussion<\/span> of why a one<\/span>-second shutter speed was chosen,\nand for other technical details about how the tests were performed.)<\/p>\n\n

For reference, here's what one of them looked like, with my\nlaptop showing the test screen in the center:<\/p>\n\n\n\n

Cropping out all but the center part of interest, the result might look\nlike this:<\/p>\n\n

\nNikon D200 + Nikkor 70-200mm f\/2.8 @ 200mm — 1 sec, f\/8, ISO 100 —\nfull exif<\/a><\/span>\nTest Pattern, from 53 Feet Away<\/span>\n<\/div>\n\n

I took long one-second exposures to highlight the ill effects of\nvibration and instability. The example<\/span> crop above might not look very\nsharp, but considering that it's a one<\/span>-second exposure and that it's a\n1\/<\/sup>44th<\/sup>-crop from the full frame, I think<\/span> it's pretty\ngood.<\/p>\n\n

It seems especially good when you compare it to using a bad<\/span> tripod, or\nhandheld without a tripod.<\/span> Mouse over the buttons below this next image, to\ncompare among a few<\/span> different results...<\/p>\n\n

\n\n