Question: FA 77 and moon, exposure problem

kamisu · 04-30-2018, 08:32 PM

Hi,

FA 77, K3, AV mode, spot metering: full moon is all white, overexposed. Is this as it should be or I am doing something wrong?

Also, with underexposing, I can get a good exposure for the moon, but then the small star/planet close to the moon completely disappears. Anything I can do to have them both in the picture?

Thanks.

Last edited by kamisu; 04-30-2018 at 08:42 PM.

Adam · 04-30-2018, 08:46 PM

I would just meter manually until you get a good result. Try to keep the shutter speed fast enough to avoid motion blur.

As for the background, I'd shoot a separate exposure for that, then combine the two.

stevebrot · 04-30-2018, 09:05 PM - **1 Like**

Originally posted by kamisu

FA 77, K3, AV mode, spot metering: full moon is all white, overexposed. Is this as it should be or I am doing something wrong?

Where was the center spot metering? If on the the moon, one would expect at least two stops underexposure. If on the black of space, the moon should be completely blown out overexposed. Conventional wisdom around these parts is ignore the meter, shoot in M mode, and calculate the exposure using the Looney 11 rule for exposure estimation.

Think of it this way, the surface of the moon is basically a sunlit desert landscape and may be treated as such, exposure-wise. There is no need for high ISO or fast lenses. The full moon has an LV (EV at ISO 100) of about 15.* That is only one stop less than sand or snow in full sun. LV 15 translates to a good starting point exposure of 1/250s and f/11 at ISO 100. Using traditional Looney 11, LV 14 would be the starting point (1/125s and f/11 at ISO 100).

Originally posted by kamisu

Also, with underexposing, I can get a good exposure for the moon, but then the small star/planet close to the moon completely disappears. Anything I can do to have them both in the picture?

Show the star, blow the moon...show the moon, clip the star. If you want them both, do what the pros do and make a composite based on two different exposures.

Steve

*
Exposure value - Wikipedia
Looney 11 rule - Wikipedia

kamisu · 04-30-2018, 09:34 PM

Thanks Adam.

Steve, thanks for the complete explanation. Center spot metering was on the full moon, so may be the sensor for spot metering is not small enough (for FA 77/moon) and covers dark sky too. With 60-250 at 250 mm I did not have such problem.

How can I make the composite image if I already have two images with different exposures for the moon and star? Does it need a software?

Last edited by kamisu; 04-30-2018 at 10:09 PM.

**BWG** · 04-30-2018, 10:38 PM - **1 Like**

When shooting the moon think of the sunny sixteen rule. It’s a face in direct sunlight, so you shoot it at f/16 and your shutter speed is one over your ISO (f/16 at 1/100th of a second). Even that may over expose a little on a full moon, but it will be close.

pschlute · 05-01-2018, 01:51 AM - **1 Like**

Originally posted by kamisu

How can I make the composite image if I already have two images with different exposures for the moon and star? Does it need a software?

You will need some editing software, payware like photoshop, or freeware.

Here is a composite image I took earlier this year. In the original shots when the moon was correctly exposed, the trees and clouds were all completely dark, and when the clouds and trees were exposed as here to bring out detail , the moon was overexposed. I cut the moon from the first exposure and popped it onto the second.

Billk · 05-01-2018, 02:20 AM - **2 Likes**

DA 300mm plus 1.4X TC, ISO 100, f 5.6m 1/800s

Manual everything, mirror up, camera K1 mounted on a tripod and remote shutter release.

PP in Lightroom with chromatic aberration reduction and profile correction, dehazing and boosted clarity and vibrance.

The moon moves through the sky very quickly and it is very bright so you need to have high shutter speed and under-expose reltive to what you expect to be correct.

Attached Images

View Picture EXIF

**MossyRocks** · 05-01-2018, 05:47 AM - **1 Like**

When shooting the moon I usually follow the looney 11 rule. Typically I use f/8, ISO 200 and 1/400s and get good results. Those settings where used for this moon picture (100% crop) which was taken with a M42 mount Vivitar 200mm f/3.5 lens.

For pictures with the moon in them it is going to likely have to be a composite image as the moon is so much brighter than everything around it so expose for the moon in one picture and then expose for everything else. Personally I like the dark silhouettes of things in front of the moon so that is what I have typically gone for when shooting scenes with the moon in them.

stevebrot · 05-01-2018, 07:49 AM

Originally posted by kamisu

so may be the sensor for spot metering is not small enough (for FA 77/moon)

Good point!

Steve

kamisu · 05-01-2018, 07:51 AM

BWG, Pschlute, Billk, Mossyrocks; thanks for the comments.

**MossyRocks** · 05-01-2018, 11:20 AM - **2 Likes**

Originally posted by kamisu

BWG, Pschlute, Billk, Mossyrocks; thanks for the comments.

Always happy to help and share things I know something about which seems to be far too little here.

leekil · 05-01-2018, 02:42 PM

The last two moon photos seem to have the moon positioned at 90-degree angles to each other. I didn't know it rotated that much!

**squareeyes** · 05-01-2018, 03:06 PM - **1 Like**

Originally posted by leekil

The last two moon photos seem to have the moon positioned at 90-degree angles to each other. I didn't know it rotated that much!

The pics were a month apart in time and nearly opposite sides of the earth, It's a wonder you couldn't see the back side of the moon!

Billk · 05-01-2018, 04:13 PM - **1 Like**

Originally posted by leekil

The last two moon photos seem to have the moon positioned at 90-degree angles to each other. I didn't know it rotated that much!

We both shot it correctly and didn't flip it in post processing (which has been suggested to me every time I post a moon shot).

The water also runs down the plug hole the other way around here and we get the best views of the Milky Way.

**squareeyes** · 05-02-2018, 04:10 AM - **1 Like**

From Spaceweather.com:
The rocking motions are called libration; because of libration we can observe not just 50% but rather 59% of the Moon's surface.

Spaceweather Glossary: Lunar Libration

04-30-2018, 08:32 PM	#1
kamisu Senior Member Join Date: Feb 2012 Location: Iowa Posts: 130	Question: FA 77 and moon, exposure problem Hi, FA 77, K3, AV mode, spot metering: full moon is all white, overexposed. Is this as it should be or I am doing something wrong? Also, with underexposing, I can get a good exposure for the moon, but then the small star/planet close to the moon completely disappears. Anything I can do to have them both in the picture? Thanks. Last edited by kamisu; 04-30-2018 at 08:42 PM.

04-30-2018, 08:46 PM	#2
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,597	I would just meter manually until you get a good result. Try to keep the shutter speed fast enough to avoid motion blur. As for the background, I'd shoot a separate exposure for that, then combine the two. Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

04-30-2018, 09:05 PM - 1 Like	#3
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by kamisu FA 77, K3, AV mode, spot metering: full moon is all white, overexposed. Is this as it should be or I am doing something wrong? Where was the center spot metering? If on the the moon, one would expect at least two stops underexposure. If on the black of space, the moon should be completely blown out overexposed. Conventional wisdom around these parts is ignore the meter, shoot in M mode, and calculate the exposure using the Looney 11 rule for exposure estimation. Think of it this way, the surface of the moon is basically a sunlit desert landscape and may be treated as such, exposure-wise. There is no need for high ISO or fast lenses. The full moon has an LV (EV at ISO 100) of about 15.* That is only one stop less than sand or snow in full sun. LV 15 translates to a good starting point exposure of 1/250s and f/11 at ISO 100. Using traditional Looney 11, LV 14 would be the starting point (1/125s and f/11 at ISO 100). Originally posted by kamisu Also, with underexposing, I can get a good exposure for the moon, but then the small star/planet close to the moon completely disappears. Anything I can do to have them both in the picture? Show the star, blow the moon...show the moon, clip the star. If you want them both, do what the pros do and make a composite based on two different exposures. Steve * Exposure value - Wikipedia Looney 11 rule - Wikipedia Last edited by stevebrot; 05-01-2018 at 07:52 AM.

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04-30-2018, 09:34 PM	#4
kamisu Senior Member Join Date: Feb 2012 Location: Iowa Posts: 130 Original Poster	Thanks Adam. Steve, thanks for the complete explanation. Center spot metering was on the full moon, so may be the sensor for spot metering is not small enough (for FA 77/moon) and covers dark sky too. With 60-250 at 250 mm I did not have such problem. How can I make the composite image if I already have two images with different exposures for the moon and star? Does it need a software? Last edited by kamisu; 04-30-2018 at 10:09 PM.

04-30-2018, 10:38 PM - 1 Like	#5
BWG Loyal Site Supporter Join Date: Feb 2007 Location: Monterey County, California Posts: 165	When shooting the moon think of the sunny sixteen rule. It’s a face in direct sunlight, so you shoot it at f/16 and your shutter speed is one over your ISO (f/16 at 1/100th of a second). Even that may over expose a little on a full moon, but it will be close.

05-01-2018, 01:51 AM - 1 Like	#6
pschlute Moderator Loyal Site Supporter Join Date: Mar 2007 Location: Surrey, UK Photos: Gallery Posts: 8,210	Originally posted by kamisu How can I make the composite image if I already have two images with different exposures for the moon and star? Does it need a software? You will need some editing software, payware like photoshop, or freeware. Here is a composite image I took earlier this year. In the original shots when the moon was correctly exposed, the trees and clouds were all completely dark, and when the clouds and trees were exposed as here to bring out detail , the moon was overexposed. I cut the moon from the first exposure and popped it onto the second.

05-01-2018, 05:47 AM - 1 Like	#8
MossyRocks Loyal Site Supporter Join Date: Nov 2017 Location: Minnesota Photos: Gallery \| Albums Posts: 2,982	When shooting the moon I usually follow the looney 11 rule. Typically I use f/8, ISO 200 and 1/400s and get good results. Those settings where used for this moon picture (100% crop) which was taken with a M42 mount Vivitar 200mm f/3.5 lens. For pictures with the moon in them it is going to likely have to be a composite image as the moon is so much brighter than everything around it so expose for the moon in one picture and then expose for everything else. Personally I like the dark silhouettes of things in front of the moon so that is what I have typically gone for when shooting scenes with the moon in them.

05-01-2018, 07:49 AM	#9
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by kamisu so may be the sensor for spot metering is not small enough (for FA 77/moon) Good point! Steve

05-01-2018, 07:51 AM	#10
kamisu Senior Member Join Date: Feb 2012 Location: Iowa Posts: 130 Original Poster	BWG, Pschlute, Billk, Mossyrocks; thanks for the comments.

05-01-2018, 11:20 AM - 2 Likes	#11
MossyRocks Loyal Site Supporter Join Date: Nov 2017 Location: Minnesota Photos: Gallery \| Albums Posts: 2,982	Originally posted by kamisu BWG, Pschlute, Billk, Mossyrocks; thanks for the comments. Always happy to help and share things I know something about which seems to be far too little here.

05-01-2018, 02:42 PM	#12
leekil Pentaxian Join Date: May 2016 Photos: Albums Posts: 2,003	The last two moon photos seem to have the moon positioned at 90-degree angles to each other. I didn't know it rotated that much!

05-01-2018, 03:06 PM - 1 Like	#13
squareeyes Site Supporter Join Date: Aug 2010 Photos: Gallery Posts: 189	Originally posted by leekil The last two moon photos seem to have the moon positioned at 90-degree angles to each other. I didn't know it rotated that much! The pics were a month apart in time and nearly opposite sides of the earth, It's a wonder you couldn't see the back side of the moon!

05-01-2018, 04:13 PM - 1 Like	#14
Billk Veteran Member Join Date: Jun 2012 Location: Melbourne, Victoria Posts: 349	Originally posted by leekil The last two moon photos seem to have the moon positioned at 90-degree angles to each other. I didn't know it rotated that much! We both shot it correctly and didn't flip it in post processing (which has been suggested to me every time I post a moon shot). The water also runs down the plug hole the other way around here and we get the best views of the Milky Way.

05-02-2018, 04:10 AM - 1 Like	#15
squareeyes Site Supporter Join Date: Aug 2010 Photos: Gallery Posts: 189	From Spaceweather.com: The rocking motions are called libration; because of libration we can observe not just 50% but rather 59% of the Moon's surface. Spaceweather Glossary: Lunar Libration