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John Jarosz
2-Jan-2021, 12:25
Today on APOD they feature the moon taken with wet plate

https://apod.nasa.gov/apod/ap210102.html

Tin Can
2-Jan-2021, 12:35
Like!




Today on APOD they feature the moon taken with wet plate

https://apod.nasa.gov/apod/ap210102.html

Vaughn
2-Jan-2021, 14:32
Linda Conner had access to some of the glass plate negatives from the Lick Obsevatory. She made some excellent POP images from them.

https://library.stanford.edu/blogs/special-collections-unbound/2020/10/starstuff-science-meets-art-print-meets-photography

ic-racer
2-Jan-2021, 14:36
Not sure I understand. Even in one second the moon is pretty blurred. How would that image be made with an 8x10 camera?

Joe O'Hara
2-Jan-2021, 14:49
Telescope with a tracking motor. With the right telescope mount, only one axis of rotation is needed.

goamules
2-Jan-2021, 17:20
Wetplate was used for astronomy for many decades, even after film. But this part of the caption has me scratching my head, what are "modern chemicals?" "This modern version of a wet-plate collodion image celebrates lunar photography's early days, reproducing the process using modern chemicals to coat a glass plate "

Ron in Arcata California
2-Jan-2021, 22:03
211108
This is a series of wet plate images I made in Oregon during the total eclipse. I custom made the camera using a 47.5 Red Dot Artar and used a half plate holder.

I was in a serious car accident that left me with a broken arm, 13 broken ribs and a pulverized heel only 5 months before the eclipse but managed to build the equipment I needed and get it to Salem Oregon in time. I made 6 images with the exposure at f/128 for 1/10 second. It would have been better to have opened the lens and shoot faster but the shutter was acting up and I ended up just capping the lens. At one point I had a plate soaking in the silver nitrate for the next shot while I was exposing the first shot. I didn't want to be stuck in my darkbox and miss the big event outside so I held off developing as long as possible.

De La Rue did a better job in 1860 but he had a crew helping him shoot the 40 8x10 plates that were made. I hope to do the same in 2024. The ether fumes in the collodion helped ease the pain in my broken leg. It was a fun project.

Fr. Mark
2-Jan-2021, 22:52
Wow! What scope mount did y'all use to facilitate tracking? I'm initially assuming the 8x10 camera is stationary. I recall seeing a mount on the Stellafane website where the axis corresponding to the north/south angle was rotating a mirror to get a bit of sunlight into a shed for observation and the remainder of the equipment or observer stays stationary. That's not common gear these days. Most scopes if they track at all (my 2 Dobsonians don't (yet!)), they move the eyepiece which means you have to drag the camera around while tracking. Adding an 8x10 to either of my scopes would mess up the balance, badly.

tgtaylor
3-Jan-2021, 12:07
You can piggyback off a telescope if the mounts motor is strong enough to carry both the OTA and camera while remaining balanced. I can piggyback a 35mm SLR with 300mm lens on my Meade 10" SCT and probably the P645NII with 400mm lens and 2x tele-extender. Check your mounts weight specifications beforehand. With the appropriate adapted you can also shoot prime focus using the telescope as your lens. On my scope that is equivalent to a 2500mm lens. With the correct adapter you can also shoot high power close-ups via eyepiece projection. For medium format photography through the telescope you will need the appropriate adapters and a scope with a 4" focuser (http://www.company7.com/astrophy/refractors/155f7-4.html#:~:text=The%20giant%204%22%20focuser%20is%20silky%20smooth%20and,camera.%20Field%20coverage%20is%203%20x%203.5%20degrees..

A relatively inexpensive option, which would be necessary for 8x10, is a dedicated mount to drive just the camera such as this mount which can handle a 22lb payload: https://www.bhphotovideo.com/c/product/1404592-REG/sky_watcher_s30500_eqm_35_mount.html/specs?msclkid=cfefd8ddfde310bb5f71872ff1eafe1b

William Whitaker
3-Jan-2021, 17:08
Perhaps a "barn door tracker (https://nightskypix.com/how-to-build-a-barn-door-tracker/)" to support an 8x10?

Fr. Mark
3-Jan-2021, 23:31
I'm amazed. I've snapped a few iPhone pics through my scopes and some friend's scopes but I never thought to mount an 8x10! Amazing!

Alan Klein
4-Jan-2021, 09:14
Today on APOD they feature the moon taken with wet plate

https://apod.nasa.gov/apod/ap210102.html

Reminds me of those old moon photos from the 1930's.

Alan Klein
4-Jan-2021, 09:15
I just bought a 10x30 binoculars. Not received yet. Could I use it for moon shots? Best way?

tgtaylor
6-Jan-2021, 13:01
Here are some images by David Malin from glass plate negatives:

Astronomical images contain light from objects covering an enormous range of brightness, far wider than found in 'everyday' photography. Of course, in astronomy, there is no way to alter the lighting, indeed it is the light itself that is the subject of the photograph.

The photographs on these pages were made in pre-digital days, using glass plates specially designed for scientific purposes, and to capture the faintest light, rather than the beauty of the night sky. However, it was possible to control the contrast and dynamic range of the image by copying the original plates through a blurred, positive copy of the original, and this has the effect of subtly sharpening the scene and revealing detail in the brighter regions, which correspond to the blackest parts of the original plates.

https://images.datacentral.org.au/malin/UKS/001

Fr. Mark
6-Jan-2021, 19:34
Here are some images by David Malin from glass plate negatives:

Astronomical images contain light from objects covering an enormous range of brightness, far wider than found in 'everyday' photography. Of course, in astronomy, there is no way to alter the lighting, indeed it is the light itself that is the subject of the photograph.

The photographs on these pages were made in pre-digital days, using glass plates specially designed for scientific purposes, and to capture the faintest light, rather than the beauty of the night sky. However, it was possible to control the contrast and dynamic range of the image by copying the original plates through a blurred, positive copy of the original, and this has the effect of subtly sharpening the scene and revealing detail in the brighter regions, which correspond to the blackest parts of the original plates.

https://images.datacentral.org.au/malin/UKS/001

y'all need to follow that link, there are TONS of great images there, I could spend a lot of time I don't have going from one link to the next!