Shooting the moon & avoiding glare

[padrepaul77]

I was trying to shoot the moon over the cathedral last night. Unfortunately, there was a bit of glare; I'd like the moon to look smooth. Is this caused by the UV filter being on the lens? Or simply because it's a 40-second exposure and the earth is moving so the moon has slightly moved in those 40 seconds? Any suggestions?

 

[Turnerea]

I'm sure some more experienced folks will comment as well, but yes... 40 seconds at pretty much any setting will greatly overexpose the moon, and that is definitely long enough to allow the moon to move through your picture.

I read someone on this forum had come up with the rule of thumb that your shutter speed has to be faster than 600/35mm equiv focal length. For estimate sake, let's say you're at 100mm 35mm equivalent, that'll give you a max shutter speed of 6 seconds. I believe this was developed for star trails, so the moon, being a whole lot closer, would require an even faster shutter speed.

The UV filter may cause some additional reflections as well, but your shutter speed is the main problem I believe. Should ditch the filter for night shooting though.

The moon is difficult to capture without silhouetting everything else around it...

 

[padrepaul77]

Thanks for the tips; though if I lower the shutter speed the moon might look good, but wouldn't the top of the cathedral be underexposed then? I like the exposure on the cathedral in the pic. Tough situation.

 

[Big Mike]

Thanks for the tips; though if I lower the shutter speed the moon might look good, but wouldn't the top of the cathedral be underexposed then? I like the exposure on the cathedral in the pic. Tough situation.

Not much you can do about that...unless you can add more light to the cathedral. Remember, the moon is being lit by direct sunlight....so it's basically as bright as anything would be at noon on a sunny day here on earth.

For something like this, you could take two shots and just combine them later.

 

[pkirchner]

I was trying to shoot the moon over the cathedral last night. Unfortunately, there was a bit of glare; I'd like the moon to look smooth. Is this caused by the UV filter being on the lens? Or simply because it's a 40-second exposure and the earth is moving so the moon has slightly moved in those 40 seconds? Any suggestions?

Take two shots, one of the church another of the moon. Combine them in PS. The moon will be properly exposed using this method. Also loose the uv filter. Pete

 

[KmH]

The Moon only reflects about 11% of the Sunlight that hits it. The technical term is albedo.

Still, it's WAY brighter than the cathedral, and as mentioned the cathedral doesn't move in a 40 second time span, but the Moon did.

Oh ya......+1 on loose the UV filter, but make sure you have the lens hood on.

 

[Dwig]

Thanks for the tips; though if I lower the shutter speed the moon might look good, but wouldn't the top of the cathedral be underexposed then? I like the exposure on the cathedral in the pic. Tough situation.

That would be "raise the shutter speed", not "lower ...". But yes, setting the correct exposure for the moon would undoubtedly result in an underexposed cathedral.

The solution is to take two exposures, one set for the moon and one for the cathedral, just as you made in your example. It would then be a simple matter to composite them in Photoshop, each on a separate layer, and use a layer mask to mask out the mis-exposed portion of the upper layer.

Back in ancient times when people used film the technique was to setup the camera and shoot the first exposure for the moon. You would then wait, preferably with a flashlight & good book to read, for a few hours until the moon moved out of the frame. You could then make a second exposure on the same frame (required a camera that allowed double-exposures with perfect registration) to get the proper exposure for the cathedral.

 

[eric-holmes]

When I shoot just the moon, I have to use a shutter speed of ~1/250 or faster to get good detail of the moon without it being blown out.

 

[pkirchner]

the UV filter being on the lens?

As I understand it, digital sensors cannot see uv light. This is a carry over from the old film days. Film can be sensitive to uv light but not digital cameras. So toss the uv filter, the more glass on your lens the better the chance for unwanted flare.

 

[Inst!nct]

couldn't you take a picture with a fast shutter speed (for the moon)
and a picture with a low shutter speed (for the cathedral)

and photoshop them together?

 

[lawrencebrussel]

i guess Big Mike is right. You won't get both in single exposure because light difference between a bright moon and cathedral is large. It's really difficult job to get the moon and the earth objects in the same exposure.

 

[480sparky]

The moon is simply another sunlit object, just like taking a photo of anything sunlit here on this planet. So exposures of the moon is the same as exposures of the kids in the back yard.