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Diffraction spike collection - add yours!

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#1 Falcon-

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Posted 12 February 2013 - 03:32 PM

Inspired by this post regarding spikes from a camera lens I started hunting up examples of diffraction spikes from my various lenses. Rather then go (somewhat) off topic there I figured I would start a new thread.

So here it is, a somewhat random collection of examples of diffraction spikes my optics have produced over the years.

Please post some examples of your own!

Edit: the 44M-4 is really at f/5.6 not f/5.8 - but kinda hard to correct it after you toss out the "temporary" document I used to add the text to the image. :shrug:

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#2 nwinston

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Posted 12 February 2013 - 04:35 PM

Here's my collection:

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#3 Falcon-

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Posted 12 February 2013 - 05:53 PM

Neil: Spikes from an 80ED? Interesting! Screws in the optical path?

How do you find the 70-200 f/4L? I recently picked up one of those myself but not had the chance to use it for astro yet.

#4 nwinston

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Posted 12 February 2013 - 07:30 PM

It's not a screw in the optical path. I've had a screw that was too long in the optical path before, and the spikes were much larger and totally different looking. I'm not sure exactly what they are, but I think the spikes are caused by three little flat spacers or holders that are along the edge the front element. I attached a picture of one of them.

I like my 70-200 F/4L. It's okay at F/4, and when stopped down to F/5.6 it's pretty sharp. Very good for a zoom lens.

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#5 jwheel

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Posted 12 February 2013 - 08:14 PM

http://www.flickr.co...57600237071127/

#6 Dave Venne

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Posted 12 February 2013 - 11:10 PM

Overhead power lines. Thank goodness they're parallel to each other.

Sorry if this is a bit off-topic, but they're a permanent part of my optical train. :(

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#7 Falcon-

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Posted 12 February 2013 - 11:26 PM

Not off topic at all, those *are* diffraction spikes after all!

Interesting effect. I wonder what would happen if you just put a small wire in front of your scope/lens perpendicular to the direction of the power lines to make that into a 4-point star instead of 2 point.

#8 Dave Venne

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Posted 12 February 2013 - 11:56 PM

I wonder what would happen if you just put a small wire in front of your scope/lens perpendicular to the direction of the power lines to make that into a 4-point star instead of 2 point.


It'd probably never look quite right...one pair would be thicker, and getting them perpendicular would be difficult. Besides, it's sort of a signature on my images. I'll keep it just the way it is. Although if the power company decides to bury the lines that would be fine with me.

#9 mmalik

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Posted 13 February 2013 - 03:54 AM

I hardly ever see diffraction spikes in my images; here is one I could find. (Alberio)

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#10 Campos

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Posted 13 February 2013 - 05:01 AM

Hi there,

I have big ones!...Difraction spykes that is :)

Here's an image I made in 2011 of the horsie with huge spykes from Alnitak.

Greets,

Luís

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#11 Tonk

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Posted 13 February 2013 - 07:49 AM

I get multicoloured ones

Posted Image

#12 bilgebay

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Posted 13 February 2013 - 08:25 AM

Tony, it is the first time I am seeing a photo of yours and it is a beauty!

You should post more often!

#13 jwheel

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Posted 13 February 2013 - 10:14 AM

Here is an odd pattern that captured last year when imaging Venus and The Pleiades:

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#14 Hilmi

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Posted 13 February 2013 - 10:34 AM

jwheel,

Now that's a funky pattern. Looks like an 80's circular wall paper pattern.

#15 Tonk

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Posted 13 February 2013 - 11:39 AM

Tony, it is the first time I am seeing a photo of yours and it is a beauty! You should post more often!


Thats because I stopped processing new images 3 years ago while doing my PhD - I had to exert some serious discipline :( else work would come second. I have to confess that I actually started processing again last week as my back log is now enormous!! (I didn't stop imaging)

See here

#16 pfile

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Posted 13 February 2013 - 01:01 PM

jwheel,

Now that's a funky pattern. Looks like an 80's circular wall paper pattern.


i've seen this when taking pictures toward the sun with my iPhone. i think it might be reflections of the microlenses over the sensor.

#17 srosenfraz

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Posted 13 February 2013 - 05:02 PM

Some really nice images in your collection. So, are you Dr. Tonk now? (if so, congrats!)






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