Wednesday, June 24, 2009

More fun with superlens

I've decided I'm going to need to go up to the eagles this weekend. I also need to find out when the next full moon is or at least when it's visible at a normal hour. Tonight I was trying for lightning bugs again. This time around, though, they're more difficult to capture because they fly out of frame so fast! So the pictures never come out in focus, because I don't have time to adjust it.

Just playing around...

From across the room, 15 feet. Not zoomed at all, so 200mm:

Some lightning bugs, wide open at f/4 and 25sec:

From the deck, probably 15 feet away, zoomed all the way to 400mm:

just a crop, not a new picture:


Another "stuff in my yard" probably 30-40 feet away:

So here's the comparison of 300mm on the 70-300 lens, and 400mm on the 200-400 (red box is field of view):
400 is 25% bigger than 300, so a first level approximation would say that the field of view should be 25% smaller this seems to be true, when comparing the measurements of the two pictures. Learn something new everyday, I guess.

I think I actually had a dream about this lens. This morning I remembered what the dream was, but now I can't recall it. I can't even remember if it was good or bad.


~~END~~

1 comment:

Anonymous said...

Regarding focus problems, I read about locking the focus if the target is staying roughly at the same distance. Thus, allowing for quicker shots. I can't remember if you lock it on the body or the lens.

Daddeo