Friday night I tried a little camera experiment that really shouldn't work. The idea being that I'd try the little trick of capturing hundreds of untracked 1-sec exposures - if you grab enough, there's a chance of getting some detail.
I've managed to stack the 600 images into one single image and processed some levels/curves to bring out the detail.
Canon 200d, Samyang 135mm lens
F/2.0. 1600iso, 600x (raw) 1sec exposures (+ 10x dark frames). - images were taken on a standard (untracked) tripod.
Stacked in Deep Sky Stacker, 32-bit Tif Levels & Curves processed In Photoshop CS3
Orion Nebula [600x 1sec images]
The Running Man Nebular is just starting to appear above Orion. It's only faint - but the purple nebulosity is definitely there
lzkaPIW.jpg
WORKFLOW:
CAPTURE:
♦ Equipment: Canon 200d, Samyang 135mm lens, Tripod (untracked mount), Hahnel Captur intervalometer (any remote shutter release will do)
♦ Camera settings: F/2.0 (aperture), 1600 (iso), 1sec (exp) - if your lens doesn't have an F/2.0 aperture, don't worry - set it to the lowest value you have. Additionally, the iso value may need to increase beyong 1600 (32000 or 6400) to compensate a little.
♦ Camera and Lens set to Manual.
♦ Manually focus the camera on the brightest star closest to your target. Star focussing is tricky - if you camera has an LCD - you're aiming to make the star look as small as possible (use LCD zoom if you have one).
♦ Images Required: 200-600x images, 10x dark frames, 10x flats
♦ make sure your camera is set to capture Raw images - Jpegs are redundant for this exercise.
(In the bitter cold I completely forgot to take "flats")
Although I captured 600 image files, 200-300 should be plenty.
♦ Position Orion slightly left of centre - this will save you having to adjust the camera position as the target slides off the right of frame.
♦ set intervalometer @ delay = 00:00'00", long = 00:00'01", interval = 00:00'02", shots = 300 (or desired value)
♦ press Start button
♦ if you've opted to capture 600 or so, remember to STOP intervalometer at 300 and reposition camera/tripod
♦ press START again.
when done press STOP and prceed to Stacking.
STACKING:
I use Deep Sky Stacker [DSS] - it's a freeware app and it removes all of the hassle from the process - when compared to trying to stack from within your imaging application.
DSS takes your images files and subtracts your darks and flats to "average out" noise while "averaging in" signal, thereby increasing the signal to noise ratio.
Load up DSS and follow these steps:
♦ click Open picture files - select all Raw images from your folder
♦ in the lower window > highlight top image > scroll to bottom > using left-shift click bottom image and click Open.
♦ Right-click and select Check
♦ You also need to load in your calibration frames, repeat the above selecting Darks and Flats separately (no need to select Check this time)
♦ From menu, select Register Check Pictures
♦ In popup box ensure all three tickboxes are checked and set Select the best to 95%
♦ Click Advanced > Click the number of detected stars button > ideally you'll need around 100. If more or less are found, move the slider and try again (80-120 is good).
♦ Click Recommended Settings > Where any item is shown in Red Click the blue link immediately below it to automatically/instantly fix these. Once done, click OK - this returns you to previous menu, click OK again
♦ This returns you to the Stacking Steps screen, click OK and away we go!
This could take a couple of hours or more. If there's loads to stack and your pc is a little older - you can leave it overnight, or alternatively go and have several cups of tea while you wait. When done DSS will have created an autosave.tif image (usually around 100-250mb). Make a note of the file location (top status bar).
♦ We're now done with DSS - close the app.
PROCESSING:
I have two old versions of PS - CS2 & CS3 - both work fine for this. I've also got Affinity and although I've not used it for this, the process is very similar - using the same functionality.
♦ Open your autosave.tif file in PS
♦ Goto Image > Mode > and change image mode from 32bit to 16bit > change Method to Exposure & Gamma > click OK
♦ Crop the image so that your 3x3 grid occupies only the point of interest and 8 identically-sized spaces around it. Ideally, you're looking at a width reduction of around 2/3 and height reduction of around 1/3.
♦ Once you have your cropped image create a duplicate layer > Always apply edits to your Working Layer - this makes it easier to back out any changes you're not happy with.
♦ Now - the fun part: bringing out the Nebulosity
♦ Image > Adjustments > Levels
> move the right-hand slider to the far right point of the histogram data display > click Ok
♦ again...Image > Adjustments > Levels
> now move the left-hand and centre sliders closer to the main histogram display - do this a little at a time. click OK
♦ Repeat the above two Levels adjustments as often as you like until you're happy with the result - but only a little adjustment each time.
♦ if the sky colour looks wrong you can adjust this by; Image > Adjustments > Levels > select middle eyedropper > find and click a part of the sky where it should be completely black > click OK
♦ Create a new layer
♦ at this stage you can adjust the hue/saturation/vibrance to suit selecting
♦ Image Adjustments > Brightness & Contrast or Image Adjustments > Hue/Saturation - do not over-egg this
Some final adjustments...
♦ next to bring out more detail click...Image Adjustments > Curves
♦ click (newer versions with Ctrl) eyedropper somewhere that the nebula appears more faint.
♦ click the histogram and pull the band up slightly (from middle-ish) to adjust the nebulosity.
♦ in the same histogram click slightly further down the band and drag it below the line > this will help to rectify the sky tone altered by previous step. when happy click OK
♦ some final fixes: create a duplicate layer and again...Image > Adjustments > Levels
♦ move the centre slider to the right to darken the sky
♦ make any final desired adjustments to hue/saturation and vibrance.
All done! - don't forget to save.
I've managed to stack the 600 images into one single image and processed some levels/curves to bring out the detail.
Canon 200d, Samyang 135mm lens
F/2.0. 1600iso, 600x (raw) 1sec exposures (+ 10x dark frames). - images were taken on a standard (untracked) tripod.
Stacked in Deep Sky Stacker, 32-bit Tif Levels & Curves processed In Photoshop CS3
Orion Nebula [600x 1sec images]
The Running Man Nebular is just starting to appear above Orion. It's only faint - but the purple nebulosity is definitely there
lzkaPIW.jpg
WORKFLOW:
CAPTURE:
♦ Equipment: Canon 200d, Samyang 135mm lens, Tripod (untracked mount), Hahnel Captur intervalometer (any remote shutter release will do)
♦ Camera settings: F/2.0 (aperture), 1600 (iso), 1sec (exp) - if your lens doesn't have an F/2.0 aperture, don't worry - set it to the lowest value you have. Additionally, the iso value may need to increase beyong 1600 (32000 or 6400) to compensate a little.
♦ Camera and Lens set to Manual.
♦ Manually focus the camera on the brightest star closest to your target. Star focussing is tricky - if you camera has an LCD - you're aiming to make the star look as small as possible (use LCD zoom if you have one).
♦ Images Required: 200-600x images, 10x dark frames, 10x flats
♦ make sure your camera is set to capture Raw images - Jpegs are redundant for this exercise.
(In the bitter cold I completely forgot to take "flats")
Although I captured 600 image files, 200-300 should be plenty.
♦ Position Orion slightly left of centre - this will save you having to adjust the camera position as the target slides off the right of frame.
♦ set intervalometer @ delay = 00:00'00", long = 00:00'01", interval = 00:00'02", shots = 300 (or desired value)
♦ press Start button
♦ if you've opted to capture 600 or so, remember to STOP intervalometer at 300 and reposition camera/tripod
♦ press START again.
when done press STOP and prceed to Stacking.
STACKING:
I use Deep Sky Stacker [DSS] - it's a freeware app and it removes all of the hassle from the process - when compared to trying to stack from within your imaging application.
DSS takes your images files and subtracts your darks and flats to "average out" noise while "averaging in" signal, thereby increasing the signal to noise ratio.
Load up DSS and follow these steps:
♦ click Open picture files - select all Raw images from your folder
♦ in the lower window > highlight top image > scroll to bottom > using left-shift click bottom image and click Open.
♦ Right-click and select Check
♦ You also need to load in your calibration frames, repeat the above selecting Darks and Flats separately (no need to select Check this time)
♦ From menu, select Register Check Pictures
♦ In popup box ensure all three tickboxes are checked and set Select the best to 95%
♦ Click Advanced > Click the number of detected stars button > ideally you'll need around 100. If more or less are found, move the slider and try again (80-120 is good).
♦ Click Recommended Settings > Where any item is shown in Red Click the blue link immediately below it to automatically/instantly fix these. Once done, click OK - this returns you to previous menu, click OK again
♦ This returns you to the Stacking Steps screen, click OK and away we go!
This could take a couple of hours or more. If there's loads to stack and your pc is a little older - you can leave it overnight, or alternatively go and have several cups of tea while you wait. When done DSS will have created an autosave.tif image (usually around 100-250mb). Make a note of the file location (top status bar).
♦ We're now done with DSS - close the app.
PROCESSING:
I have two old versions of PS - CS2 & CS3 - both work fine for this. I've also got Affinity and although I've not used it for this, the process is very similar - using the same functionality.
♦ Open your autosave.tif file in PS
♦ Goto Image > Mode > and change image mode from 32bit to 16bit > change Method to Exposure & Gamma > click OK
♦ Crop the image so that your 3x3 grid occupies only the point of interest and 8 identically-sized spaces around it. Ideally, you're looking at a width reduction of around 2/3 and height reduction of around 1/3.
♦ Once you have your cropped image create a duplicate layer > Always apply edits to your Working Layer - this makes it easier to back out any changes you're not happy with.
♦ Now - the fun part: bringing out the Nebulosity
♦ Image > Adjustments > Levels
> move the right-hand slider to the far right point of the histogram data display > click Ok
♦ again...Image > Adjustments > Levels
> now move the left-hand and centre sliders closer to the main histogram display - do this a little at a time. click OK
♦ Repeat the above two Levels adjustments as often as you like until you're happy with the result - but only a little adjustment each time.
♦ if the sky colour looks wrong you can adjust this by; Image > Adjustments > Levels > select middle eyedropper > find and click a part of the sky where it should be completely black > click OK
♦ Create a new layer
♦ at this stage you can adjust the hue/saturation/vibrance to suit selecting
♦ Image Adjustments > Brightness & Contrast or Image Adjustments > Hue/Saturation - do not over-egg this
Some final adjustments...
♦ next to bring out more detail click...Image Adjustments > Curves
♦ click (newer versions with Ctrl) eyedropper somewhere that the nebula appears more faint.
♦ click the histogram and pull the band up slightly (from middle-ish) to adjust the nebulosity.
♦ in the same histogram click slightly further down the band and drag it below the line > this will help to rectify the sky tone altered by previous step. when happy click OK
♦ some final fixes: create a duplicate layer and again...Image > Adjustments > Levels
♦ move the centre slider to the right to darken the sky
♦ make any final desired adjustments to hue/saturation and vibrance.
All done! - don't forget to save.
Comment