Full Moon and Solar Setup

Sony a6000, Canon 400mm f5.6 L lens              

First, while my dislocated thumb heals I'm limited in what I can get accomplished around the house so I wanted to write a little bit about a photo of the full moon that I shot a few months ago. 

I belong to a few different astrophotography and astronomy groups and someone was asking about lenses for photographing the moon so I helped them out with a few tips. Afterward, I got to thinking that the info I shared with that astronomy group would probably be good to share here too. 

The main reason for the request for help was to help the person choose a lens that would be good for photographing the moon. For this type of photography, most people recommend a 70-300mm lens but I've never been happy shooting with a standard 70-300mm lens. That being said, I have managed to get a few decent shots over the years using a 70-300mm lens on a smaller 4/3-sized sensor. The advantage of the smaller sensor is it doubles the equivalent focal length so my shots with that particular lens and camera were the equivalent of shooting with a 600mm lens. The disadvantage was that I was stuck using a smaller sensor which significantly impacts image quality. I did, however, manage to get a few decent shots over a few years. Most of my shots, however, were poor and were worthy only of the trash bin. 

If you are using an APS-C sized sensor...  which is the size sensor in most dSLR's... the quality improves but you lose some focal length compared to the smaller sized 4/3 sensor. Aside from losing some reach, the biggest problem here is that most 70-300mm lenses are only of "kit lens" quality... which means "fair" quality for the price. As a result, I've never really been happy with my long shooting until I purchased a used 400mm prime lens. There is a world of difference in image quality and reach.

Even with the longer 400mm f5.6 L lens, I still had to crop the above moon image to only 25% of its original size to get what we see above (a 24 megapixel image cropped to only 6 megapixels). That's still throwing away a lot of pixels even with a very large lens. A 70-300mm lens simply cannot match what we see here under the same conditions.

Another thing I wanted to point out is a terrible mistake I see in about 90% of all moon images I see online... It is very easy to overexpose moon images!  This big rock orbiting Earth is reflecting the bright sun so it is exceptionally bright. In fact, when the moon is full, it lights up the sky and the ground and is even painfully bright to view through a telescope! You really need to dial down the exposure time which means shooting in manual exposure mode and manual focus mode.

As an example of proper exposure for the moon (although it will vary a bit depending upon atmospheric and weather conditions), I shot the above image at f8, ISO 100, and at a shutter speed of only 1/640th of a second. The exposure was so short that I was able to hold my camera and big 400mm lens in my hand rather than mount it on a tripod and yet I still captured a crisp photo with no signs of camera shake. 

So... you need to shoot in manual mode... choose the correct exposure... focus manually... white balance on auto or daylight... and purchase the best and longest lens you can afford. If necessary, mount your camera and lens on a tripod to avoid camera shake. 

            Explore Scientific 102mm ED telescope, Sony a6000 camera

Another option would be, rather than shooting through a lens, you shoot through a telescope. 

This image, at left, was shot through my Explore Scientific 102mm ED telescope which has a focal length of 714mm. This telescope is far larger than the lens I used for the shot of the moon at the top of the page and the quality of this telescope is outstanding so, naturally, we see a marked improvement in image quality. 

I shot a series of ten or so images and stacked them to create a super-resolution image. I still used the same camera as I did in the image at the top of the page but because I stacked the images, the resulting resolution is at 85 megapixels rather than 6 megapixels that we see in the top image. The result is a far more detailed view of the moon. Even though this image, above on the left, is already very detailed, I'm hoping to get even better results in future astrophotography sessions. Admittedly, I am a perfectionist and I'm always looking to improve... which can be exhausting.

I also meant to share a photo of the setup I used yesterday when I was outside for my solar astrophotography session. I meant to share it in yesterday's blog entry but I had forgotten to include this image strip. 

I had setup the telescopes on our front deck. A deck is typically not advised for telescopes because any footsteps will vibrate the telescope but, since I was alone on the deck, I knew when to move around and when to stay perfectly still. The deck was convenient because I had easy and fast access to the house. 

The image on the left shows our deck with the telescopes...  the center image shows my new Meade Solar Wedge with the sun illuminating the back of the Wedge... and, on the right, is my first view and photo of our sun. The resulting solar image... my first image and my first view of the sun... actually... looks great! 

I'm looking forward to more astrophotography as the weather, atmosphere and my health allows. I'd like to get more closeup images of the moon, more detailed images of the sun, and a few images of some deep sky objects. 

This is a great hobby but, because so many conditions must be just right all at the same time, it really is a frustratingly slow moving hobby.