OT: Small Astronomical Treat - Moon & Venus in Conjunction

[polaraligned]

Also digital cameras are great and digital image sensors can be used for longer exposures, but for really dim, far off objects I suspect that actual film cameras are still used, at least for some long term exposures like all night long and even multiple nights in some cases.

I highly doubt film is being used anymore. CCD's are superior in resolution, they are more sensitive, have much higher quantum efficiency, and their response is linear. They also have greater dynamic range and do not suffer reciprocity failure. The only advantage of film is size of sensor area. Nobody takes an "all night" exposure anymore. You take multiple exposures and stack them. This is very easy to do with digital images.

Amateur astronomy is what got me into machining, and I have seen amateurs take pictures that are far better than some of the old glass plate pictures that came off of the 200" Hale telescope.

My dream project is to take this 29.5" f/3.3 mirror I have and turn it into an astrograph. I have big $$ invested in the optics, but little time to move it forward. It was cast from borosilicate by Dream Cellular and the optics were figured by Lockwood Optics.

[Ringo]

Err, not so fast. Yes, amateurs can take some spectacular photos of the heavens. But forty years ago (71 actually) we did have the 200", Hale Telescope on Mt. Palomar and I can guarantee you that it was and still is a LOT better than anything that anyone has in their back yards today and probably for the foreseeable future. It was preceded by the 100", Hooker telescope at Mt. Wilson Observatory which also totally outclasses any and all amateur scopes.

And we, of course have even better scopes today.

Also digital cameras are great and digital image sensors can be used for longer exposures, but for really dim, far off objects I suspect that actual film cameras are still used, at least for some long term exposures like all night long and even multiple nights in some cases.

https://en.wikipedia.org/wiki/Palomar_Observatory

https://en.wikipedia.org/wiki/Mount_Wilson_Observatory

Err, I'm still thinking yes so fast,
40 years ago Hales/Palomar was using film and analog computers and slide rules. They had a really big mirror, but their processing was still basic film.
today, amateurs have backyard mirrors, plus modern CCD cameras, modern photo processing, and I believe they can surpass what Hales/Palomar did 40 years ago.

BUT, TODAY, Hales/Palomar has CCD cameras, modern computers, and they got got everything the backyard guy has, plus more, AND a really big mirror.

[J Tiers]

Well for some events, no particularly special equipment is needed!

[aostling]

That's a great photo. But in Phoenix, AZ, you have the home field advantage, in spades!

Thanks to Marv's recommendation (#9) I have now increased that advantage. By installing the Stellarium Plus app on my iPhone I can now name any star I can see in the sky. The app puts the LCD screen in reddish "night mode" so that your night vision is not impaired. You simply point the screen anywhere to see a rendering of what surrounds the axis of the camera. It shows all the planets and constellations, even those that are below the horizon (on the sunny side of the earth).

I want to see the Pleiades. My father once pointed them out to me from the backyard of our house in Seattle. In 1952 Seattle skies were dark, unpolluted by street lighting. I only recently learned that Subaru is the Japanese name for this star cluster, which also inspires the six stars in the company's logo. I have just returned from a 10 P.M. walk on the nearby Foothills Golf Course https://goo.gl/maps/4LQnJNrt5XUD5c7FA. The moon had not yet risen so the sky was rather dark (but too close to the light pollution of Phoenix on the north side of South Mountain to see much of the Milky Way). Stellarium informed me that the Pleiades will be rising shortly after the moon.

What I find astounding is that the app shows trees and house shapes on the horizon. Is this just a cartoon? I wondered. It is not -- somehow my iPhone camera is sensitive enough to populate the silhouette with the actual trees and houses which are on both sides of hole #6, where I was plopped down on the grass!

p.s. Perhaps you think 10 P.M. is too early for dark skies in the summer. Not a problem in Phoenix -- along with Hawaii, Arizona never changes the clocks forward or backward. The summer sun is the "enemy" so nobody here wants to "save" it. Sometimes it stays above 100ºF until midnight.

[Paul Alciatore]

That is one beautiful piece of glass. Yea, yea, I know it is not common glass. I am just saying I'm impressed. I bet it cost a nickle or two.

I highly doubt film is being used anymore. CCD's are superior in resolution, they are more sensitive, have much higher quantum efficiency, and their response is linear. They also have greater dynamic range and do not suffer reciprocity failure. The only advantage of film is size of sensor area. Nobody takes an "all night" exposure anymore. You take multiple exposures and stack them. This is very easy to do with digital images.

Amateur astronomy is what got me into machining, and I have seen amateurs take pictures that are far better than some of the old glass plate pictures that came off of the 200" Hale telescope.

My dream project is to take this 29.5" f/3.3 mirror I have and turn it into an astrograph. I have big $$ invested in the optics, but little time to move it forward. It was cast from borosilicate by Dream Cellular and the optics were figured by Lockwood Optics.

[fjk]

Someone mentioned the 200” telescope
theres a great book about its construction “The Perfect Machine”