Decision help wanted (I've done my homework) - 1Ds MkIII vs 1DMk IV, specifically AF

[scalesusa]

I have a 5D MK II, and had a 40D as backup. i decided to buy a 7D as a birding camera, but decided that it was too specialized and returned it and bought another used 40D. Then, I had a opportunity to buy a almost unused 1D MK III, so I bought it and sold the 40D.


It gets much more use than the 7D did, at a couple of hundred more than the 7d, I much prefer it.


As I see it, the advantage to me of the 1D MK IV is the high iso. When photographing rapidly moving objects, a fast shutter speed is better, 1/2000 sec is often ideal. That combined with a slightly stopped down aperture requires high ISO, so that would be a improvement. My 1D MK III can shoot at ISO 3200 with good results, but not 6400.


I would be able to use 6400 or maybe 12800 on a mark IV. That translates to smaller apertures and or higher shutter speeds and sharper images.

[waltgary]

In what way did you fail? It is hard to say what went wrong without knowing what you were going for and what you ended up with

Seeing what you and Mr Browning wrote, I suspect my using AF or infinityMFwas the isssue, along with many others. I will be using your suggestions in the next week or two and see if I can get something. I wasn't anywhere near a 30 second exposure nor did I try live view/manual focus so this is a good starting point. That was the final piece I was missing before being able to get a decent shot (by my standards) of the moon. I can never seem to get my head around not using infinity focus for something so far away.


gary

[waltgary]

You may want to read this ...





http://www.robgalbraith.com/bins/multi_page.asp?cid=7-10048-10484





Bob

I've bookmarked your link and will review the article as time permits. Thank you, gary

[waltgary]

Interesting. I wonder how the 7d compares? gary

[MikeWhy]

For lack of other answers, I'll throw in my experience this past weekend with the 7D. I'm a complete novice at machinegunning, but took advantage of the uncharacteristic sunny two days shooting my two Labradors playing in a nearby field and small lake. Of about 1200 shots total, I kept 963. Surprisingly few were outright garbage with nothing in focus or focused on the background. Some contained only partial dogs. I kept a few that will print well at small sizes but are slightly out of focus. The remaining 923 are in critically sharp focus. The keeper rate improved greatly as I learned to frame and track, and more importantly figured out the appropriate settings. The bigger problem is what to keep and what to throw away.


The conditions weren't particularly challenging. Some were backlit in full afternoon sun and unbroken snow. Some were shot against competing backgrounds of chainlink, brush, and tall grass. The least challenging were of them running full tilt directly at the camera. I'm guessing they do about 25 mph in full stride, figuring about 3 seconds for 40 yards.


I have little expectation that the 7D is of the same caliber as the 1D4. At the same time, I don't see how the AF tracking can be meaningfully improved. Almost all the garbage shots were made early on as I figured out the settings and how to frame and track. A bit more practice and I'll be ready to go pro. As it stands, the 7D is already ready.