Humayun QureshiHumayun Qureshi

Delivering Aesthetically-Delivering Aesthetically-Pleasing DSLR ImagesPleasing DSLR Images

About MeAbout Me

What I’m Going to PresentWhat I’m Going to Present

Software ListingSoftware Listing

IntroductionIntroduction

About MeAbout MeTechnicalTechnical

CreativeCreative

What I’m Going to PresentWhat I’m Going to PresentWhen Mark Approached Me...When Mark Approached Me...

Theory, in Practice (pre), and In Practice (post)Theory, in Practice (pre), and In Practice (post)

Disclaimer: Right or Wrong?Disclaimer: Right or Wrong?

Software ListingSoftware ListingIRISIRIS

Adobe PhotoshopAdobe Photoshop

Diffraction Limited MaxIm DLDiffraction Limited MaxIm DL

Simulation Curriculum Starry Night Pro PlusSimulation Curriculum Starry Night Pro Plus

Canon EOS Utility & Digital Photo ProfessionalCanon EOS Utility & Digital Photo Professional

TheoryTheoryCompositionComposition

CompositionCompositionWhat is Composition?What is Composition?

What is Composition?What is Composition?““The organisation or grouping of the different parts The organisation or grouping of the different parts of a work of art so as to achieve a unified whole.”of a work of art so as to achieve a unified whole.”

What is Composition?What is Composition?The The pleasant arrangementpleasant arrangement of of subject mattersubject matter in a in a frameframe which has a which has a powerfulpowerful ability to ability to attractattract the the eye and keep it eye and keep it exploringexploring the image for as the image for as longlong as as possible.possible.

The Rule of ThirdsThe Rule of ThirdsFocal points in a composition should fall on lines of thirds.Focal points in a composition should fall on lines of thirds.

Example: at least one eye in a portrait.Example: at least one eye in a portrait.

Example: the Sun or Moon or planets in a terrestrial image.Example: the Sun or Moon or planets in a terrestrial image.

Example: bright stars or object of interest in an Example: bright stars or object of interest in an astrophotograph.astrophotograph.

FramingFramingWhat is Framing?What is Framing?

What is Framing?What is Framing?Framing is what you do with your camera, with Framing is what you do with your camera, with regards to orientation.regards to orientation.

The aim is to try and present the simplest and most The aim is to try and present the simplest and most balanced scene.balanced scene.

CroppingCroppingThe easiest way to frame your scene in a balanced and pleasing The easiest way to frame your scene in a balanced and pleasing way is to crop your final image.way is to crop your final image.

We’re often hesitant to throw away all that precious sensor space, We’re often hesitant to throw away all that precious sensor space, but, thinking about the way some bright objects may appear in the but, thinking about the way some bright objects may appear in the frame with relation to the main subject matter, may assist in frame with relation to the main subject matter, may assist in providing for a more pleasing composition.providing for a more pleasing composition.

Using Planetarium Software Using Planetarium Software for Compositionfor CompositionCamera OrientationCamera Orientation

Non-centred compositions work if other objects can be included to Non-centred compositions work if other objects can be included to balance.balance.

Harder for long focal length imaging due to guide star constraints, Harder for long focal length imaging due to guide star constraints, but, cropping the final image appropriately can help here.but, cropping the final image appropriately can help here.

In Practise (pre)In Practise (pre)CaptureCapture

CalibrateCalibrate

Register, Crop, Normalise, Stack and StretchRegister, Crop, Normalise, Stack and Stretch

CaptureCaptureUsing Software to Gauge ExposureUsing Software to Gauge Exposure

Using Software to Gauge Using Software to Gauge ExposureExposureExposure LengthExposure Length

Histograms and Simulated Exposure LengthHistograms and Simulated Exposure Length

Highlight and Shadow ClippingHighlight and Shadow Clipping

Exposure LengthExposure LengthDark Skies vs Suburban SkiesDark Skies vs Suburban Skies

ISO Limitations and Capabilities in Older and New ISO Limitations and Capabilities in Older and New CamerasCameras

(ISO-400=300 seconds; ISO-800=150 seconds; ISO-(ISO-400=300 seconds; ISO-800=150 seconds; ISO-1600=75 seconds)1600=75 seconds)

Histograms and Simulated Histograms and Simulated Exposure LengthExposure LengthExample: Digital Photo Professional show’s a good histogram Example: Digital Photo Professional show’s a good histogram at 30 seconds for a test exposure taken at ISO-6400.at 30 seconds for a test exposure taken at ISO-6400.

ISO-6400=30 seconds; ISO-3200=60 seconds; ISO-1600=120 ISO-6400=30 seconds; ISO-3200=60 seconds; ISO-1600=120 seconds.seconds.

Exploit RAW latitude to work out your optimum exposure.Exploit RAW latitude to work out your optimum exposure.

Highlight and Shadow Highlight and Shadow ClippingClippingAlt+M and Alt+N in DPP will show where clipping is Alt+M and Alt+N in DPP will show where clipping is occurring as a blue and red mask; adjust your occurring as a blue and red mask; adjust your exposure until clipping is minimised.exposure until clipping is minimised.

Inevitability of Highlight ClippingInevitability of Highlight Clipping

CalibrationCalibrationDark FramesDark Frames

Flat Frames (And, Associated Dark Frames)Flat Frames (And, Associated Dark Frames)

Dark FramesDark FramesWhen and What to CaptureWhen and What to Capture

The Use of Dark LibrariesThe Use of Dark Libraries

Flat Frames (And, Associated Flat Frames (And, Associated Dark Frames)Dark Frames)How and What to CaptureHow and What to Capture

Software-Assisted CaptureSoftware-Assisted Capture

How and What to CaptureHow and What to CaptureThe Use of Lightboxes, Light Panels and Computer The Use of Lightboxes, Light Panels and Computer ScreensScreens

Capture somewhere in the vicinity of 16-25 frames and Capture somewhere in the vicinity of 16-25 frames and median combine.median combine.

At lowest native ISO setting of your system.At lowest native ISO setting of your system.

Software-Assisted CaptureSoftware-Assisted CaptureUse histogram displayed in DPP to fine tune your Use histogram displayed in DPP to fine tune your exposure.exposure.

Register, Crop, Normalise, Register, Crop, Normalise, Stack and StretchStack and StretchIRIS’ Powerful Registration CommandsIRIS’ Powerful Registration Commands

Crop Redundant AreasCrop Redundant Areas

NormaliseNormalise

Kappa-Sigma StackingKappa-Sigma Stacking

StretchingStretching

IRIS’ Powerful Registration IRIS’ Powerful Registration CommandsCommandscoregister2 <input> <output> <numfiles>coregister2 <input> <output> <numfiles>

coregister4coregister4

Crop Redundant AreasCrop Redundant AreasFor normalising and for the kappa-sigma stacking For normalising and for the kappa-sigma stacking routine.routine.

window2 <input> <output> x1 y1 x2 y2 <numfiles>window2 <input> <output> x1 y1 x2 y2 <numfiles>

Ignore Black PixelsIgnore Black Pixels

NormaliseNormaliseNormalising (or, offsetting) sets median value of the Normalising (or, offsetting) sets median value of the background in each image to 0.background in each image to 0.

This aids in increasing dynamic range and allows kappa-sigma This aids in increasing dynamic range and allows kappa-sigma stacking to work optimally.stacking to work optimally.

noffset2 <input> <output> 0 <numfiles>noffset2 <input> <output> 0 <numfiles>

Kappa-Sigma StackingKappa-Sigma StackingIdeal solution is the sum of all images (caveat: cosmic rays, satellite trails, aeroplane Ideal solution is the sum of all images (caveat: cosmic rays, satellite trails, aeroplane trails, outlying data).trails, outlying data).

Median is a better option, but, still not the best as it has low signal-to-noise compared Median is a better option, but, still not the best as it has low signal-to-noise compared to summation.to summation.

Kappa-sigma takes the best of both of the above algorithms.Kappa-sigma takes the best of both of the above algorithms.

composit command.composit command.

MaxIm DL SD Clip.MaxIm DL SD Clip.

StretchingStretchingarcsin hyperbolic stretching -- form of non-linear stretching.arcsin hyperbolic stretching -- form of non-linear stretching.

asinh <alpha> <intensity>asinh <alpha> <intensity>

Same result acheivable in MaxIm DL by using DDP but disabling Same result acheivable in MaxIm DL by using DDP but disabling the kernel filters.the kernel filters.

Click background point and mid-level.Click background point and mid-level.

In Practise (post)In Practise (post)LevelsLevels

CurvesCurves

Vibrance and SaturationVibrance and Saturation

LevelsLevelsUse levels adjustment layer to fix colour balance.Use levels adjustment layer to fix colour balance.

Select each individual channel, hold the Alt key down, and move the Select each individual channel, hold the Alt key down, and move the mouse in from the left to see where clipping starts to occur in the mouse in from the left to see where clipping starts to occur in the shadows.shadows.

Do the same from the right hand side of the levels dialog to see where Do the same from the right hand side of the levels dialog to see where highlights start to clip -- typically, stars will be clipped a bit.highlights start to clip -- typically, stars will be clipped a bit.

CurvesCurvesUse curves adjustment layers to increase brightness.Use curves adjustment layers to increase brightness.

Try using the built-in Photoshop default curves Try using the built-in Photoshop default curves adjustments such as lighten, and also the linear adjustments such as lighten, and also the linear contrast curves adjustments layers.contrast curves adjustments layers.

Vibrance and SaturationVibrance and SaturationUse the vibrance adjustment layer to handle vibrance and also saturation.Use the vibrance adjustment layer to handle vibrance and also saturation.

Increasing vibrance takes the dullest colours in the image and increases Increasing vibrance takes the dullest colours in the image and increases their saturation.their saturation.

Take care not to overdo it as you will start to introduce artefacts in your Take care not to overdo it as you will start to introduce artefacts in your image (I use a vibrance setting of 20<x<50 and saturation 10-20% of image (I use a vibrance setting of 20<x<50 and saturation 10-20% of vibrance).vibrance).