- ページ 9

アクセサリー DayStar Filters Magnesium Quark EyepieceのPDF ユーザーマニュアルをオンラインで閲覧またはダウンロードできます。DayStar Filters Magnesium Quark Eyepiece 17 ページ。

ページを印刷する

Lucky Imaging:

Virtually all solar imaging can benefit from the technique of Lucky

Imaging, where a high speed camera is used to capture hundreds or

thousands of frames in a short time span. Then

software can be

used to select and stack just the frames least affected

atmospheric

this

function

include

Exposure time:

Imaging solar vs. nighttime astrophotography is very different.

Dark sky

long exposure times to capture

light.

Solar

offers ample light, so exposures should be very short.

Plus,

fluctuations in

dictate that short <1/10 second frame rates will be

better, as seeing cells move quickly to distort the image and can come

and go during a long exposure.

• Short exposure webcam

are beUer than long exposure

CCD cameras when imaging

sun.

• Because the sun has a range of

automatic

exposure doesn't work well. A software interface that allows the

user to control the exposure settings manually is very important.

Exposures in Magnesium should be kept to 1/30 second or less in order

to capture the fleeting moments of good seeing. Increasing camera gain

or addition of a focal reducer AFTER the Quark can improve exposure

times.

Bit depth:

Solar activity encompasses a wide dynamic brightness range from bright

solar flares to faint eruptive or floating prominences quite a distance from

the solar limb (in Hydrogen Alpha). In order to

all these

we recommend the use of 12 bit or 16 bit cameras.

Normal 8 bit

cameras can be

but will typically only be able to image either the

surface or

in Hydrogen

multiple

bracketed exposures and subsequent recombination in a com puter. 12

bit or 16 bit cameras enable capturing these features in the same

exposure, simplifying the image processing.