a6400 astrophotography noob

[FowlersFreeTime]

Hey fellow Alpha Shooters,
I was up in Vermont last weekend where there were some suitably dark skies and I thought I might try my hand at photographing the stars. I did not have a good tripod or a star chart, I just wanted to see how it would turn out with my kit lenses. So I took these two shots with the Sony 10-18mm at f4. I wish I had reviewed properly at the time because it looks like I didn't quite get the focus right. I'm very open to constructive criticism!

• ILCE-6400
• E 10-18mm F4 OSS
• 16.0 mm
• ƒ/4
• 25 sec
• ISO 3200

• ILCE-6400
• E 10-18mm F4 OSS
• 16.0 mm
• ƒ/4
• 25 sec
• ISO 3200

 

[Ivanturas]

Yeah... you don't need to wait for the pic to be ready and review it, just zoom in on your screen to focus in detail. Also, see what's the longest exposure you can use without getting stars trailing. There's quite a bunch of exposure calculators online.

Last but not least, you can try stacking several exposures, in order to minimize noise. It's similar to other stacking processes, but if you haven't stacked anything at all, I'll happily help you out.

 

[FowlersFreeTime]

Thanks Ivan! I thought about stacking, but realized I was moving my camera too much between shots. I will definitely be using manual focus next time as well.

 

[Astrnmrtom]

Great first shots! Yes, when it comes to shooting point sources of light like stars, exact focus is critical, and is the most difficult part of astrophotography, well, that and tracking. A couple tricks for getting good focus: First, pick the brightest star or stars in the area, and as suggested, zoom in on the screen to focus and when you do focus, rock your focus ring back and forth to pass back and forth through best focus while watching the screen. You'll be better able to zero in on best focus using this technique. Another trick is to slightly bracket your focus. I found turning off focus assist actually helped because the highlighting pixels in the viewfinder prevented me from seeing point of best focus. Always use a remote, or the camera's self timer to prevent shake. I've found Sony's remote trigger app that uses the viewfinder eye sensor to trigger the shutter works quite well. As Ivan mentioned, there's online calculators to help you determine the maximum exposure time you can use with your lens before the stars start to trail. Another trick you can do if you are using a cheaper lens that has some chromatic aberration, giving you purple halos around stars, is to set your camera to mono or black and white mode. Try to find a balance between sensitivity and ISO settings to minimize noise - I usually stay at 1600 or below. Attached is a photo taken last month of the Orion area. I was using a manual focus 12mm f/2.8 lens on my a6000. To start, I suggest you keep it simple. don't worry about getting a special lens, just use what you have and refine your basic techniques. When the time comes, one manual focus lens that gets good reviews for wide field astrophotography - and landscapes - is the Rokinon 12mm f2.0. I didn't want to spend that amount of money for casual wide field shots, so I got the cheaper, and slightly slower, Meike 12mm f/2.8. It's the lens used in the attached photo. It costs $169 vs the Rokinon's $300+ So far I've been pleased with the results. I've even been pleased with the kit lens that came with my a6000. It produces purple halos around the stars, but I remove them in software, or use the mono mode trick. One important thing to note when comparing my photo to your own is that this image was taken far away from any city lights. The glow at the horizon is from a small town about 25 miles away. Note the winter Milky Way passing diagonally through the photo. If you zoom in, you'll see my focus was a tiny bit off, and at a 30 second exposure, my stars are just beginning to elongate. This was shot at ISO 3200.

Once you have your techniques down with your existing equipment, and you want to go to the next level, look at a fast lens and try your hand at stacking. Until that, keep it basic so you don't pile one learning curve on top of another. I've been doing specialized astro-imaging for years, but wide field astrophotography with the Sony is new to me, and I have to keep reminding myself to keep things simple, that I'm a beginner in this type of imaging as well.

Tom

 

[FowlersFreeTime]

Many thanks Tom, some good tips there.
I wish I could try it more often, but living in South Florida, our skies are full of light pollution and clouds (oh that humidity!). So I likely won't be able to try again until my next trip to my sister-in-law's cabin in Vermont. I will definitely be paying closer attention to manual focus and will pack my Sigma 16 f1.4 instead of my Sony 10-18 f4.