What focal length lens do I need for photographing the moon?

Question

I would like to know whether it is possible to photograph moon without any flaws with a canon EOS 550d..

Also to get an image of the moon as close as the following image, what kind of equipment(lens,etc) is need to be used with the 550d Body

Answer 1

You can certainly take such an image with a 550D, but to get it that size without cropping will take a lens of about 1200mm or so. The moon occupies about one-half degree of arc, and a 1200mm lens on the 550D's sensor will yield a (short-side) field of view of just under three-quarters of a degree, which is just a little bit tighter than the framing here. An 800mm lens with a 1.4x teleconverter will yield almost exactly the same framing as this picture. A 600mm with a 2x teleconverter will be just a bit tighter.

If the image is for screen display or a small print, don't be afraid to shoot at 300mm and crop. You'll still wind up with an image that's about 1730x2600 pixels, which is bigger than most monitors and will print a reasonable-quality 8x10 or 8x12 (or a superb 6x9).

Answer 2

You found the image at Mansurov's How to Photograph the Moon, so I think that's a good place to look for answers. Since he suggests using a 300mm lens and 1.4x or 2x teleconverter, I would bet those were used. Additionally, he also mentions that regardless of focal length, you are likely going to want to crop to get a tight photo.

Answer 3

See my answer over here... I explain in detail how to get this kind of shot. Basically a good quality long lens (NOT cheap nasty 75-300 type thing), with it in manual focus mode and Manual mode on the camera too.... Read the post for information.

Answer 4

Ideally, if you want to get as close as possible with minimum noise, you should rent out a high-quality 600mm lens like the Canon 600mm f/4L IS, the kind wildlife photographers use (typical 2012 rate: $400 for 5 days). The moon occupies a very small angular range and the less cropping you have to do the better. However if you're willing to raise ISO a little bit you can use a 300mm with a 2x teleconverter, and this is cheaper.

Also remember that there's more to shooting the moon than filling the frame - you have to choose your time carefully to get good shadows, and meter correctly to get good exposure.

Answer 5

A correction: the Moon subtends 0.5 degrees, not "about 1".

I have taken good Moon shots using my Celestron C8 telescope OTA in conjunction with a focal reducer - equivalent to 1000mm / f/6.3 - using my Pentax K100D at prime focus. The image closely fills the 2/3 sensor, maximizing the use of the available pixels. Which is only 6M for the Pentax, but still a pleasing result.

see reduced resolution for web at:

http://davidwarman.net/Pictures/Astronomy/slides/Snow-Moon-hi.html

Ask me for the full-resolution (3000x2000 with full EXIF info) version if you want to analyze the original.

Answer 6

Here is an uncropped photo I had taken of the Moon about a year ago.

^{_{(Be forgiving of the softness)}}

As you can see, it fits cozily within the frame.

This was taken using a Canon EOS 600d, which is comparable to the 550d, and using a t-ring setup attached to the Celestron Nexstar 4se, which has a focal distance of 1325mm. I wouldn't want to get much closer than this, as the Moon moves quite quickly at this focal distance - camera shake can be a real problem and the Moon can move completely out of the frame within 10 seconds.

Answer 7

Here's a rule of thumb: you need about 100 mm of focal length per millimeter of sensor height in order for the moon to fill just under 90% of the height of the image frame (i.e., mostly fill it up).

A bit more precisely, you need approximately 115 mm of focal length / mm of sensor height to completely fill the frame.

So for a Canon APS-C camera with a sensor height of 14.9 mm, you need a 1500 mm lens (or equivalent lens + teleconverter) to frame the moon to 90% of the height of the image. A full-frame camera body with 24 mm sensor height would need a 2400 mm lens to achieve the same image, without cropping.

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This rule comes from the angle of view formula: AoV = 2 * atan(d/2ƒ), where d is the height of the sensor, and ƒ is the focal length of the lens. Since we already know that the moon subtends an angle of about 0.5° of arc, we just solve the equation for ƒ/d, which yields ƒ = 114.6 mm / mm of sensor height.

Just multiply that ƒ/d number by the fill ratio/percentage if you don't want the moon to fill the image. For instance, if you want the moon to fill only 50% of the height of the image, just multiply 115 by 0.5, or about 57 mm per mm of sensor height.

Answer 8

You won't be capturing the amount of detail in the example image. If you happen to have:

• A crop sensor camera
• a 55-250mm zoom lens
• A quality tripod, not a cheapo one

...you can take pretty okay picture of the moon but no way will it have the amount of detail in the example image.

Use f/8 to get most out of the lens, larger apertures (smaller F-numbers) have blurrier pictures due to the lens and so do smaller apertures (larger F-numbers) due to diffraction. At f/8, 1/200 s and ISO 100 you get the optimal exposure. Turn off image stabilization if the tripod is a high-quality one. Use 10-second selfie timer or a remote shutter release to avoid shaking the tripod. Do manual focusing and refocus for every shot. Keeping live view mode always on avoids shaking the camera on first curtain. 10x magnification is required for focusing in live view mode.

Without a tripod, turn on image stabilization and you also could use autofocus because manually focusing without a tripod isn't practical. However, it may be difficult to get autofocus to work on the moon.

Here's an example image of what the crop sensor equipment gives you if you take 20 shots on tripod manually refocusing every time and pick the best (768 x 768 crop from 6000 x 4000 image):

Here's also an example image of what you can do with 10 shots and picking the best, autofocus and no tripod, image stabilization on (800 x 800 crop from 6000 x 4000 image):

For more detail, you need to take as many as 100 shots, pick the 20 best, and combine them in a picture-combining software to increase detail.

Hope these examples explain what the limits of standard crop sensor equipment are. Longer focal lengths are always an option, but e.g. Canon 500mm prime costs nearly as much as a very small car! 100-400 could be an option, but even it is somewhat expensive.