Nightscape photography - What am I doing wrong?

[limvo05]

Hello Experts,

My first night in Zion National Park was a disaster. I tried to take photos of the night sky but to no success. Despited the fact that I thought I did everything right to get a decent photo of the stars, the photo came out BLACK!

Below are the settings:

1. Manual settings.

2. Focal length was 24mm

3. Applied the 500 rule, i.e. 500/24 = roughly my shutter speed (21 seconds).

4. ISO 2000

5. Aperture 2.8

6. Manual focused on the distant star.

7. Steady tripod.

There was no wind, or cloud of any kind. Granted there was no milkway to been seen, that said, I was expecting to have at least captured all the stars when looking with my naked eyes.

Please let me know what I am doing wrong? I am heading over to Bryce Canyon tomorrow morningm hopefully, I'll figured out what I am doing wrong by then.

Thank you,

LV

[kvbarkley]

Hard to say.

I took the following (after a moon shot - hence the long lens) with my 150-600 lens at 150mm, f/5, 15 secs, ISO 400.  It is a shot of Orion. Note that star trails are visible. You should have gotten more than me.

You only took 1 shot?

[ebiggs1]

"1. Manual settings.

2. Focal length was 24mm

3. Applied the 500 rule, i.e. 500/24 = roughly my shutter speed (21 seconds).

4. ISO 2000

5. Aperture 2.8

6. Manual focused on the distant star.

7. Steady tripod."

8. Bracket  <--- you new best friend  

[kvbarkley]

Sounds like you did enough right to be close and get *something*.

If your camera is an APS camera, you need to use the equivalent focal length for your calculations.

http://learn.usa.canon.com/resources/blogs/2016/20160812-schall-star-shooting-blog.shtml

[limvo05]

I am using the Canon 5Ds.

I am begining to wonder if I have to do a whole lot of post processing to get anything decent?

Will try again tonight. Last night in Zion before heading over to Bryce.

Stay tune for uodate, thanks

LV

[limvo05]

FYI. I tried ISO 3200 and it was horrible, so grainy.

[ebiggs1]

With the exposure you listed you should have gotten some stars.  Something else is wrong so you need look elsewhere for the issue.  What was on the LCD back?

[RobertTheFat]

---

@kvbarkley wrote:

Sounds like you did enough right to be close and get *something*.

If your camera is an APS camera, you need to use the equivalent focal length for your calculations.

---

Why? The APS-C sensor size affects neither the shuttrer speed of the camera nor the aperture of the lens.

[limvo05]

Does the sky has to be pitch black? Unfortunately, where my camp site is at, there is this bright street light, that said, if i can see it with my naked eyes, should the camera not able to pick up the same?

[kvbarkley]

Because the F/500 rule is dependent on the angle of view.  I.e., the stars move at so many degrees per second, so to prevent star trails you want the amount of time it takes to move one pixel.