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View Full Version : Dancing to a different drummer again



Diane Miller
10-25-2014, 11:52 AM
I appreciate the indulgence here for allowing the occasional skyscape. This isn't the most exciting subject in the normal landscape sense, but it is exciting in that this is the biggest sunspot in many years. Several Earths would fit in the larger hole.

Canon 5D3, Canon 600mmf/4 II + 2X TC, big Gitzo, Wimberley II head, solar filter. ISO 1600, f/9, 1/5000 sec. That may seem extreme, but at that focal length and with only the center support of the lens foot, the lens rings like a bell at the slightest perturbation, and the sun moves through the frame at a noticeable rate. I used Live View to get mirror lockup, and a remote release after a several second pause after the mirror went up. The air was mercifully still -- a light breeze would probably have trashed sharpness.

Having the sun's "atmosphere" in addition to ours is a double whammy.

Don Railton
10-26-2014, 12:58 AM
Hi Diane, considering the distance between you and the subject I find this impressively sharp.. Those that do this sort of photography every day will have a more valued opinion no doubt, but I like what you have achieved anyway... Do you do these shots at night when the air is cooler?

Don


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Diane Miller
10-26-2014, 09:25 AM
Night? Wish I could.... But this is the sun. You're correct though that our atmosphere (and the assorted moisture and pollutants in it) is the limiting factor for IQ. I try to do sun and moon shots when they're at the highest elevation so I'm looking through a thinner layer of atmosphere. And if I can get to a high and dry location, that's excellent, but the best ones are a day's drive or more and, in summer, generally downwind of some big fire.

Don Railton
10-26-2014, 07:01 PM
Hi Diane... WHAT was I thinking..!!! clearly not when this celestial body might be visible. But you are right in that I was considering what conditions limit IQ for these sort of shots. I remember planning a moonrise, borrowing a 2x converter to stack on my 1.4 and 500mm, heading off to a local hilltop, hoping to get the moon rising between some palm trees I could see on the horizon... It was a beautiful warm balmy summer evening. All I got was a big orange blob that looked like a bowl of jelly in a spin dryer. It was hard to tell it was the moon, there was sooo much (I think its diffraction..) from the turbulence generated from hot air rising off the earth into the cooler sky.

Best regards
DON

Andrew McLachlan
10-26-2014, 07:04 PM
Hi Diane, very cool sun-scape...I think it might be the first one we've had here :S3:

Dvir Barkay
10-26-2014, 07:27 PM
very nice, and I think a job well done Diane! For a second I forgot you used a filter and thought, wow, she must have had a hard time focusing on the sun looking at it through a viewfinder with a 1200mm worth of focal length, she must have been blinded, than I remembered you used a filter. I can imagine it would only take mere seconds to really hurt your vision looking at the sun without a filter at such a focal length. Anyhow, well done, like this one very much.

Diane Miller
10-26-2014, 07:35 PM
More like milliseconds, or less. Not to mention melting the sensor. This is a special solar filter designed for photography, not just viewing. It filters out IR (for heat) as well as visible light. You can get the material as coated mylar sheets fairy inexpensively from www.thousandoaksoptical. Just stretch and tape over the lens hood - carefully.