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Old Jul 18, 2007, 11:42 PM   #1
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Last week I decided to see what would happen if I were to add my homemade extension tube to the A*300. My extension tube started out in life as a very poor PentaxK-mount 2X TC but works as an extension tube now that I've removed the glass.

It seemed like the closest focusing distance went from 11-15 feet down toaround 5 1/2feet or so (a little more than I am tall), not as much as I was hoping for but quite a bit better for close-up stuff.

My experiment took place at lunch time in the botanical garden (a favorite haunt of mine for taking a break at work) so no tripod, everything had to be hand-held. The first thing I really noticed was just how much light I lost due to the tube - it was difficult to keep my shutter speeds up (but did surprise myself by having one picture taken at 1/25 that was actually reasonably sharp). Second thing I noticed was how awkward the lens suddenly became.

My conclusion - this is not a combination for handholding (anyone who can manage this same lens with a real TC has to have awesome technique and be a whole lot steadier than I am!), I got far fewer decent pictures with this combination. I didn't think I got the focusing distance to be close enough to make it worth-while. The pictures that I got were pretty good (better than the Phoenix) but not enough better to replace the dedicated macro lens. But it was an interesting exercise.

Here are a couple of shots:
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Old Jul 18, 2007, 11:43 PM   #2
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Leaf:
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Old Jul 18, 2007, 11:43 PM   #3
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Bark of a gum tree.
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Old Jul 18, 2007, 11:45 PM   #4
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Spray flower. I try to take pictures of these tree flowers quite often (find them fascinating). The color on this one is better than what I usually get with the Phoenix.
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Old Jul 19, 2007, 12:10 AM   #5
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I like them but as you would, I'd opt for a more dedicated short lens. They are sharp.

Dawg
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Old Jul 19, 2007, 12:29 AM   #6
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Hi Harriet,

I think that they're all terrific shots, but if the combo is that cumbersome for you, then that takes the fun out of it.

You might consider this setup for for birds at a feeder with focus trap shots off a tripod though. It's obviously a capable setup from an optical standpoint. With the closer focusing disatnce, a sharp 300mm can do some awesome things.
. . . just a thought. . .

Scott
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Old Jul 19, 2007, 4:53 AM   #7
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mtngal wrote:
Quote:
My conclusion - this is not a combination for handholding (anyone who can manage this same lens with a real TC has to have awesome technique and be a whole lot steadier than I am!),
i'll have to try this with mine. one thing you didn't try was using the flash. it can make all the difference shooting close ups.

roy
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Old Jul 19, 2007, 8:01 AM   #8
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Roy - I didn't think about using the on-board flash, and I still don't have a flash unit. The one or two times I've tried to use the flash with a manual lens, it didn't work right - I'm sure it's what I'm doing wrong because I don't understand it. And my homemade extension tube is a K-mount, so it turns the A lens into a manual K lens. I really should figure out flash and get a unit for these types of things. As everyone noticed, the pictures are incredibly sharp (when there's no camera shake).
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Old Jul 19, 2007, 10:34 AM   #9
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mtngal wrote:
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Roy - I didn't think about using the on-board flash, and I still don't have a flash unit. The one or two times I've tried to use the flash with a manual lens, it didn't work right - I'm sure it's what I'm doing wrong because I don't understand it. And my homemade extension tube is a K-mount, so it turns the A lens into a manual K lens. I really should figure out flash and get a unit for these types of things. As everyone noticed, the pictures are incredibly sharp (when there's no camera shake).
If you look back a few months, there was a very good tutorial posted which dealt with using a flash.



Darren
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Old Jul 19, 2007, 12:07 PM   #10
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In spite of your reservations, Harriet, the results are very encouraging! I'll have to try this with my A* 200mm and tubes.

Kjell
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