{"id":33750,"date":"2022-07-20T00:00:00","date_gmt":"2022-07-20T00:00:00","guid":{"rendered":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/?post_type=purple_issue&p=33750"},"modified":"2022-07-21T14:15:42","modified_gmt":"2022-07-21T14:15:42","slug":"capture-bright-moon-not-a-problem","status":"publish","type":"post","link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/2022\/07\/20\/capture-bright-moon-not-a-problem\/","title":{"rendered":"Capture: Bright Moon? Not a problem"},"content":{"rendered":"\n

Take the perfect astrophoto with our step-by-step guide <\/p>\n\n

ASTROPHOTOGRAPHY <\/span><\/h5>\n\n

CAPTURE<\/span><\/h2>\n\n
\n\n

Bright Moon? Not a problem <\/h2>\n\n

The Moon may wash out this year\u2019s Perseid meteor shower, but there\u2019s always hope <\/p>\n\n

\"\"
Composite Perseid image captured on the night of 12\/13 August 2014, with a 92%-lit waning gibbous Moon lighting up the sky <\/figcaption><\/figure>\n\n

Visually, this year\u2019s Perseid meteor shower will be something of a washout due to the presence of a bright Moon around the period of peak activity. Photographically, however, there is hope. <\/p>\n\n

A camera set up to do a multi-second exposure of the night sky will typically return a bright, overexposed frame if the Moon is nearby. However, with careful tuning of the camera\u2019s settings, it is possible to reduce the intensity of the recorded background sky so that it doesn\u2019t overexpose. For example, reducing the camera\u2019s sensitivity (low ISO, small aperture) will deliver a multi-second exposure without overexposure. Under normal nighttime conditions, such settings probably wouldn\u2019t record many meteors. <\/p>\n\n

To work here, the camera needs to be set to the settings you would normally use for meteor imaging \u2013 high ISO and wide aperture \u2013 but the exposure time needs to be reduced to prevent sky overexposure. In this way, if a meteor trail passes through the camera frame, it should record just as it would if the sky were darker and the exposure longer. There are caveats hough. Shorter exposures mean more shots will be taken. The ideal filetype here is your camera\u2019s RAW image format, and such files tend to be on the large side. Lots of large image files means you need plenty of storage available, but for modern cameras this shouldn\u2019t be too much of an issue. More frames also require more time to check afterwards.<\/span><\/p>\n\n

Mind the gap <\/strong><\/h4>\n\n

The use of RAW means that at the end of each shot a fair amount of data needs to be transferred to your camera\u2019s storage card. This can create a \u2018gap\u2019 in your camera\u2019s imaging capability, a period when no image is being taken. Under normal \u2018dark sky\u2019 meteor exposure settings, this gap will be far shorter than the exposure time. However, when the Moon is about and exposure times need to be radically shortened, the gap becomes significant. <\/p>\n\n

For example, a one-second gap vs a 29-second exposure means that only two seconds of imaging time is lost per minute (3.3%). However, if the exposure time is reduced to one second, this equals the gap time. Consequently, 30 seconds are lost per minute of imaging time (50%). A shorter exposure also raises the probability of truncating a meteor trail mid-flight, something that increases for brighter and longer meteor trails. <\/p>\n\n

Although not ideal, it is still possible to set up a camera to record this year\u2019s Perseid shower and, given clear weather, there\u2019s every chance that you will be able to record some trails. And as it\u2019s likely there will be fewer people out having a go on the night of the 12th\/13th, if you do capture a bright trail you may well be the only one to do so. Follow our How To guide opposite and see what you can catch. <\/p>\n\n

Equipment: DSLR camera, MILC camera, tripod or tracking mount, remote shutter release <\/p>\n\n

Send your images to: gallery@skyatnightmagazine.com<\/a><\/strong><\/strong><\/p>\n\n

\n\n

Step by step <\/strong><\/h4>\n\n

STEP 1 <\/strong><\/p>\n\n

Choose a lens that will give you a good field of view but avoid going too wide as the trails will appear small and unimpressive. Something around the 14\u201318mm mark would be a good compromise. Have a set of charged batteries ready as well as plenty of storage cards and a lockable remote shutter cable.<\/span><\/p>\n\n

\"\"<\/figure><\/div>\n\n

STEP 2 <\/strong><\/p>\n\n

The camera will need to be mounted on a stable platform. A tripod will keep the camera still as the sky moves through the field of view. A tracking mount will keep the camera pointing at the same area of sky. If using a tracking mount, make sure the camera doesn\u2019t end up pointing at a foreground object. <\/p>\n\n

\"\"<\/figure><\/div>\n\n

STEP 3 <\/strong><\/p>\n\n

Set camera and lens to manual and check the camera clock. <\/p>\n\n

Pre-focus at infinity using a bright target such as Jupiter. Older cameras should be set to an ISO value of 3200 or 6400, while more modern bodies can go further, eg 5000-10,000. Fully open the aperture, reducing by a stop or two if edge stars distort. <\/p>\n\n

\"\"<\/figure><\/div>\n\n

STEP 4 <\/strong><\/p>\n\n

Aim at an area of sky that won\u2019t bring the Moon into frame. Set a test exposure of 5s and take a shot. Examine the sky. If it\u2019s overexposed, reduce the exposure. If it appears dark, consider increasing exposure. Reduce ISO or aperture only if you can\u2019t get a non-overexposed sky with less than a 1s exposure. <\/p>\n\n

\"\"<\/figure><\/div>\n\n

STEP 5 <\/strong><\/p>\n\n

Set the camera to continuous shutter mode and lock the button down on a connected remote shutter cable. The camera should continuously take shots at the pre-set exposure. Routinely check the lens for moisture, using a 12V hairdryer to remove any. A 12V heater band is a recommended alternative if you have one. <\/p>\n\n

\"\"<\/figure><\/div>\n\n

STEP 6 <\/strong><\/p>\n\n

Capture for as long as you can. Download the results. Using a viewing app, examine each image in turn. Renaming any suspected trail images with a prefix (eg \u2018meteor_\u2019) makes them easier to find later on. Perseid trails should align with the radiant and often show green-pink coloration. <\/p>\n\n

\"\"<\/figure><\/div>\n\n

<\/p>\n\n

\n\n
\"\"<\/figure><\/div>\n\n

Pete Lawrence is an expert astro-imager and a presenter on The Sky at Night<\/p>\n\n

<\/p>\n\n

<\/p>\n\n

Photos: PETE LAWRENCE <\/p>\n\n

<\/p>\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

The Moon may wash out this year\u2019s Perseid meteor shower, but there\u2019s always hope<\/p>\n","protected":false},"author":24,"featured_media":33742,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ub_ctt_via":"","purple_page_number":"76","purple_custom_meta_purple_page_number":"76","purple_seq_number":"1","purple_custom_meta_purple_seq_number":"1","purple_source_article":"article_76-1.xml","purple_custom_meta_purple_source_article":"article_76-1.xml","purple_source_issue":"August-2022","purple_custom_meta_purple_source_issue":"August-2022","purple_external_id":"August-2022-76-1","purple_custom_meta_purple_external_id":"August-2022-76-1","purple_issue_code":"|0000086555||","purple_custom_meta_purple_issue_code":"|0000086555||","purple_android_product":"com.im.skyatnight.207","purple_custom_meta_purple_android_product":"com.im.skyatnight.207","purple_ios_product":"com.im.skyatnight.207","purple_custom_meta_purple_ios_product":"com.im.skyatnight.207","purple_web_product":"","purple_custom_meta_purple_web_product":"","purple_publication_id":"075fab74-0a21-4201-866a-899d6c41c40c","purple_migrated":"","kt_blocks_editor_width":""},"categories":[34],"tags":[14],"featured_image_src":"https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/07\/0b74e6f8-78cd-4194-ba3e-58d93c7e973e.jpg","author_info":{"display_name":"importmanagerhub@sprylab.com","author_link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/author\/importmanagerhubsprylab-com\/"},"acf":{"readingTimeMinutes":"5","apple_news_title":""},"uagb_featured_image_src":{"full":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/07\/0b74e6f8-78cd-4194-ba3e-58d93c7e973e.jpg",1397,869,false],"thumbnail":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/07\/0b74e6f8-78cd-4194-ba3e-58d93c7e973e-150x150.jpg",150,150,true],"medium":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/07\/0b74e6f8-78cd-4194-ba3e-58d93c7e973e-300x187.jpg",300,187,true],"medium_large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/07\/0b74e6f8-78cd-4194-ba3e-58d93c7e973e-768x478.jpg",768,478,true],"large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/07\/0b74e6f8-78cd-4194-ba3e-58d93c7e973e-1024x637.jpg",800,498,true],"1536x1536":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/07\/0b74e6f8-78cd-4194-ba3e-58d93c7e973e.jpg",1397,869,false],"2048x2048":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/07\/0b74e6f8-78cd-4194-ba3e-58d93c7e973e.jpg",1397,869,false]},"uagb_author_info":{"display_name":"importmanagerhub@sprylab.com","author_link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/author\/importmanagerhubsprylab-com\/"},"uagb_comment_info":0,"uagb_excerpt":"The Moon may wash out this year\u2019s Perseid meteor shower, but there\u2019s always hope","_links":{"self":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/33750"}],"collection":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/users\/24"}],"replies":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/comments?post=33750"}],"version-history":[{"count":11,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/33750\/revisions"}],"predecessor-version":[{"id":34222,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/33750\/revisions\/34222"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media\/33742"}],"wp:attachment":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media?parent=33750"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/categories?post=33750"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/tags?post=33750"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}