Maybe not so exciting an image to some, but I have never tried anything like this before and tried this tonight as Jupiter was so bright.
Canon 7D
Canon EF400mm f/5.6L + 2X TC
1 sec f/11 ISO 800 MLU
Huge crop in CS5
NR in Noiseware Pro
Maybe not so exciting an image to some, but I have never tried anything like this before and tried this tonight as Jupiter was so bright.
Canon 7D
Canon EF400mm f/5.6L + 2X TC
1 sec f/11 ISO 800 MLU
Huge crop in CS5
NR in Noiseware Pro
You do have a nice diagonal with the planet and stars. If you were able to get a whole sky full of stars with this - that would be something.
Hi Ian, Agree with Robert about having more interest within the image. The diagonal alignment is interesting...
Thanks for the comments, folks. These were Jupiter's moons and not stars, so a different layout would have been tough. I took this because I had never seen the moons so clearly as last night. It was a relatively starless night. I might take a trip out into the desert this weekend to see if I can get this with stars around it.
Hey Ian,
Agree with the comments above......but given your limitations.....still quite interesting. I'm impressed that you got such a good image......you had to be a good distance from Pheonix because of all the light pollution. Having more stars in would be a great idea Robert gave you!
Ian,
The 1 second exposure time is too long. You've staurated both Jupiter and its moons. Also, such a long exposure time at these magnifications result in motion blur due to the Earth's rotation. Jupiter appears about 40 arc-seconds across, and the Earth rotates (on the celestial equator) at a rate of 15 arc-seconds per second. So Jupiter moves about 1/3 its diameter in one second. Try keeping your exposure to shorter than about 1/15 second.
Imaging the planets with a telephoto lens is quite a technical challenge. There is a thread in the gear forum about stacking 2x TCs. Her is my first attempt at Jupiter with stacked 2x TCs on a 500 mm lens:
http://www.birdphotographers.net/for...70294#poststop
It is a 1/50 second exposure (I think the ISO was 200 or 400--need to check). You can faintly see 3 moons. If the atmosphere and camera were more stable, the moons would be sharper and appear brighter. So one can image both Jupiter and its 4 Galilean moons in one exposure and maintain detail on Jupiter.
For computing the exposure time, Jupiter is not quite 5 times further away from the Sun than the Earth, but its clouds are a little brighter than an 18% gray card (same with the moons). So 5 times further away would mean 25 times less sunlight, so 25 times longer exposure than sunny f/16 rule, but then a little faster than that, so 15 to 20 times longer than the sunny f/16 rule. In my image above, I was underexposing to keep the exposure time short to reduce motion blur.
Roger
Wow, Roger. Thank you so much! I was getting trails with 10 second exposures and thought my tripod was moving! If I get a chance, I'm going out again tonight to try your method! This was the best I got the other night. This was 1 sec, f/11, ISO 1000 and now I know that's way too long.
EDIT: I just tried controlling focus on my 7D with my laptop and liveview and it works well. I think I'm going to have to try that with the camera on the tripod tonight too.
Last edited by Ian Cassell; 09-26-2010 at 08:26 PM.