[Phaser]

It was very hard to focus the camera properly on the tripod since it was pointing upward.

Manuell focus set to infinity?

Here it's to light to make shots of the moon this days but i have borrowed a Tamron 400mm 5,6 which i think would do the job.

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Last edited by Phaser; 06-20-2008 at 11:58 PM.

[boren]

I made several attempts. At 1/125 I couldn't quite keep the shots sharp. But at 1/180 they were.

I had to use F9.5 instead of F11 which was recommended earlier. F11 was underexposing with the DA 50-200.



Nice shots. It sure looks like the magnification helped !



How much does that telescope cost ?

I'm not sure why stopping down the lens is a good idea. The moon is at infinity, open it up to the lenses best aperture (on mine it's closer to f6-f8).

The magnification does help, but it's also the light gathering abilitf that a 10" scope brings. The full moon is so bright that it will almost blind you, and you'll have moon ghosting on your retina for an hour afterwards. It's a hell of a lot cheaper than a $6000 lens holly crap, seriously. If you want to do astrophotography you can almost buy a mount and scope for that

The setup is an Orion Skyquest xt10i. You can almost the same scope from a different vendor for $600, and $100 for the eyepiece and afocal mounting ring. This isn't a good general astrophotography rig though, it only works on really bright things like the moon and maybe saturn/jupiter.

The "right way" to do it though is prime focus. When I took the pictures the camera was mounted to an eyepiece with 8-12 elements in it, then through a lens with ~5-6 elements. That's a LOT of glass to go through. In prime focus you mount the camera without lens straight to the scope then use the telescope as a 1250mm lens. This way you have only defects in the mirror to worry about, and it projects a great image right onto the sensor. Sadly though it's setup for visual use, and I would need to shorten the optical path to achieve prime focus. That means a new focuser or moving the main mirror about 2". A pain just to take moon shots.

Beats the pants off of a $6000 lens, probably better pictures too.

[kmccanta]

If prime focus works... then you can use the DSLR as the eye piece right?

[boren]

If prime focus works... then you can use the DSLR as the eye piece right?

Correct.


The telescope in this case preforms the exact function of a lens.

[kmccanta]

Can you post a picture of your setup... hopefully you have another camera you can use...

I am curious what this rig looks like.

[boren]

Here you go, I'm not fond of using the 18-55mm, I only have the 52mm ring. I have the 49mm ring on order so I can use the 50mm f/1.4.

Eyepiece, lens and mounting ring:



The two mounted together:



Lens eyepiece assembly on the telescope:



Camera, lens, eyepiece, telescope:

[DJey]

When I saw the thread, I thought it was moon scenes! Ahahah..

[LeoTaylor]

Here is a video of the February Lunar Eclipse taken with my filterless K110D and a 8 inch Schmidt Cassegrain Telescope. The normally f10 scope had an f6.3 reducer for an effective focal length of 1250 mm. I used prime focus as described by Boren. The camera attaches to the scope with a T-ring thus there is no glass in the path, only two mirrors between the sky and the sensor. The scope is motorized to track the movement of the heavens.

Eclipse of the Moon Video

A DSLR without Live View is at a disadvantage in Astrophotography, focus becomes very tedious. I usually do Moon craters with a Phillips ToUcam which I can view live on a computer. I take hundreds of frames per photo at 6000mm then average them together.

I can take a photo of the Pentax/SCT and Pentax/Refractor setups I use if you would be interested. I bought my first refractor when I realized a 400mm f/5 telescope at $199 cost far less than an equivalent lens. It also doubled as a telescope. Years later the Pentax and Tamron 75-300mm came out at $129 each from B&H. I should try a Moon photo with with my 300mm lens and see how it performs. Next clear morning I'll take the waning Moon.

[vizjerei]

Here you go, I'm not fond of using the 18-55mm, I only have the 52mm ring. I have the 49mm ring on order so I can use the 50mm f/1.4.

Eyepiece, lens and mounting ring:

Wow this is interesting, is it easy to find those mounting rings?

[boren]

For the hyperion line of eyepieces yes. They are threaded so they can take an adapter. I don't know of any others that are though. Great overall eyepieces too.

Link: Digital Photography T-Rings and Adapters

[LeoTaylor]

I took photos of my filterless K110D attached to my SCT (2000mm f10) and Refractor (480mm f6). I use Prime Focus, the only adapter is a T-ring, under $15. Most of my telescopes came to focus with a camera as is. Only a 4.5 in reflector needed a optional focuser to focus a camera at infinity.

Efforts to take a Moon shot with the Tamron 70-300 are being thwarted by early morning thin clouds. I got up at 4 AM and could only see 2 bright stars overhead. I went back to bed.

[kmccanta]

Cool, thanks for showing off your setups!!

This is very interesting, I will have to learn some more...

-k

[LeoTaylor]

Finally I had a clear night to take two Moon photos with my K100D. Both used an equatorial mount that tracks the heavens. Both are processed with Paint Shop Pro 11. Note I did not use my modified K110D to keep the colors "normal" but the time of day changed the color anyway. It was not truly dark when I took the smaller image.

The smaller image was taken with a Tamron 75-300mm lens ($129) at f 5.6. The Moon is about 327 pixels wide, not enough magnification to do the camera justice.

The larger images was taken with a Stellarvue 480mm Telescope ($399) using a 2x Barlow (AKA teleconverter) resulting in 960mm at f12. The photo is scaled down to 750 pixels suqare since the Moon was 1580 pixels wide. For some reason the forum kept scaling it smaller, so I placed it on the web.

The craters always show best near the light/dark terminator when the Moon is not full. Shadows give you some idea of height and shape.

http://pages.cthome.net/astroleo/moon960mm.jpg