Tag Archives: GIMP

Geminid Photobombing Orion 14 December 2020

Canon 60D, ISO 1600, f/2, 15 seconds, Sigma 30mm F1.4 EX DC (HSM).* The lens is 48mm equivalent field of view with the 60D’s 1.6X crop factor. For meteors, a wider lens is better but this is what I have in sharp, fast glass. I got a couple of meteor images at 30 seconds but the stars are little glow worms.

Geminid meteor photobombing Orion

No post processing other than resizing.


Geminid meteor photobombing Orion

I’ll list post processing below.


Some of the stars in the original, particularly Orion’s belt, have red halos so looking at them zoomed out they look pink.

First, I desaturated the red channel on selected stars.

Next I used the Focus Magic filter to undo some motion blur (about 7 pixels). I’m using a demo version and still learning my way around it. It tends to oversharpen but I think that’s more a function of my ignorance than anything wrong with the algorithm. The demo is nice. It doesn’t cripple the software or add a watermark, you just have a limit of 10 images.

Pixel-peeping to see how well the blur removal worked, I found more red halos and did another round of selective red desaturation.

In GIMP, I adjusted the exposure to -0.750. An un-adjusted image comes up with exposure ‘0’. I’m not sure what the units are but I tweaked to taste. The trees lost a little glow but the sky looks more like what my eyes saw. I’ll probably play some more. If anything worth seeing comes out of it, I’ll update this post.

* This lens is discontinued. I got mine as a Sigma factory refurbished lens when the model was still current. Some “new old stock” is available depending on mount and mint used ones can be picked up inexpensively. The newer version is part of Sigma’s “Art” series. It costs a bit more (MSRP $499) and is tweakable with their USB dock.

Trip MD – Playing With GIMP Filters On A Ruined Roll

Kind of a long post so scroll down or go back if you get bored.

I mentioned the failed 1st roll (Alaris 200 color print film) in the Olympus Trip MD post. My C-41 developer was too old so most of the negatives came out really bad. The scanner has to boost the gain to get something and it introduces a lot of noise. Once I saw them, I didn’t really take care of them and they got dust and scratches. I scanned them any way but results were not pretty. While another roll was scanning, I played with some GIMP filters to kill time.

Peach tree.

Peach tree.


Peach tree - edge detect filter.

Peach tree – edge detect filter.


Peach tree - neon filter. I can't remember if neon was added to edge.

Peach tree – neon filter. I can’t remember if neon was added to edge.


Most of the filters can be tuned so the effects aren’t so drastic but I was messing with scans I didn’t really care about any way.

Our friend's horse. I seem to have gotten my shadow in a lot of these too.

Our friend’s horse. I seem to have gotten my shadow in a lot of these too.


Our friend's horse - "old photo" filter.

Our friend’s horse – “old photo” filter.


Grass & Flower.

Grass & Flower.


Grass & Flower - cropped to the grass.

Grass & Flower – cropped to the grass.


These filtered versions of the grass aren’t really identifiable, but they came out kind of cool.
Grass - "circuit" filter.

Grass – “circuit” filter.


Grass - "lava" filter.

Grass – “lava” filter.


Mean turkey and a rooster - a lousy image without the dev problem.

Mean turkey and a rooster – a lousy image without the dev problem.


Mean turkey and a rooster - edge filter.

Mean turkey and a rooster – edge filter.


Propane tank, apple tree, & truck.

Propane tank, apple tree, & truck.


Propane tank, apple tree, & truck - "graphic pen" filter.

Propane tank, apple tree, & truck – “graphic pen” filter.


Dragon kite.

Dragon kite.


Dragon kite - cropped & neon filter.

Dragon kite – cropped & neon filter.


And the best for last.
Trinity is not happy.

Trinity is not happy.


Trinity is not happy - cropped & neon filter.

Trinity is not happy – cropped & neon filter.


Trinity is not happy - cropped & "little planet" filter.

Trinity is not happy – cropped & “little planet” filter.

GIMP has gotten really good. I can’t find the Photoshop Elements 8 installer I got with the Canon Scanner. I re-bought PSE (version 15) since Adobe doesn’t have installers going back that far, even if you have your serial number. I think it was installed on a drive I wiped without freeing up the license so I don’t know if it’s doable even if I find the disc. PSE 15 kind of sucks compared to the older version. I just have GIMP 2.10 on the laptop. The workflow is different but it easily rivals PSE now and maybe full Photoshop. I hate the software as a service model so even if I thought PS “Creative Cloud” was worth the extra money, I probably wouldn’t get it.