24 replies to this topic

[mloffland]

Introduction to Fishing For Photons

By: Craig Stark

[Doug76]

Nice reading.
Knew I'd heard that name before. I was a bigtime fan of Stereo Review, and got started in my first career, Audio Technician, because of that mag, and The Beatles. As with any gear head, the equipment reviews were my favorites.

[chboss]

Looking for more of Craigs Writing.
Both entertaining and full of good information.

Cheers
Chris

[Jim Rosenstock]

Ummmm....you won't find "the glow of the Triangulum area" anywhere near M42....

Trapezium , perhaps??

[John Wunderlin]

Craig- I thoroughly enjoyed reading your history. I think many of us share similar experiences to your own first light with the camera. I'm looking forward to your 'official' contributions to CN!

[psetnik]

Welcome, welcome, welcome. I, too, remember your father's writings.

I congratulate you on following in his footsteps. And if your writing in general is as clear and engaging as your introduction, I will look forward to reading and learning.

Regards,

Phil

[jrbarnett]

Welcome Craig.

Regards.

Jim

[quantumac]

Thanks Craig. Fishing for photons in the dark is indeed a challenging pastime.

Some of my relatives and friends wonder why I do it. They point to books and the internet, saying I could see it all in pictures taken by professionals.

I explain my hobby like this: imagine trying to take a picture of something blacker than tar moving across the sky. Imagine you must take multiple long exposures, at night, while compensating for mechanical deflections measured in thousandths of inch, wild temperature variations, camera noise, light pollution, shifting winds, clouds, dew and bugs, all constantly trying to foul you up. Imagine waiting until the skies are clear, it's the weekend (so you can stay up late), and there's no appreciable moonlight. After overcoming adversity, the end result is something your human eyes could never see on their own, and you were the one who captured it.

I think it's worth the effort, and it's far more entertaining than most of the mind-rot on television.

[RHK]

Craig, I enjoyed your column. I'm just starting to consider doing some astrophotography and look forward to your future articles.
I just have two requests. First, please don't assume that everyone is using Windows-based PCs for image processing. I use Macs. Second, when you get around to discussing specific hardware and software, please address the ranges of hardware and software available in terms of cost, features, capabilities, etc. Too many AP articles I've read expect that everyone will be using the top-of-the-line equipment, or nearly so.
Thanks.

[Craig]

Ummmm....you won't find "the glow of the Triangulum area" anywhere near M42....

Trapezium , perhaps??

Doh! Just wait until a buddy of mine sees this. I've still not lived down the craterlets inside the crater Pluto (posted to a group 2x).

Craig

[Craig]

Craig, I enjoyed your column. I'm just starting to consider doing some astrophotography and look forward to your future articles.
I just have two requests. First, please don't assume that everyone is using Windows-based PCs for image processing. I use Macs. Second, when you get around to discussing specific hardware and software, please address the ranges of hardware and software available in terms of cost, features, capabilities, etc. Too many AP articles I've read expect that everyone will be using the top-of-the-line equipment, or nearly so.
Thanks.

It'd be tough for me to make the first assumption as I'm writing this on my MacBook Pro. Guess where I do all of the software development work (including my Windows development)... As for the second -- that's always on my radar as well.

Craig

[Craig]

Phil & Doug,

It's nice to hear of folks who knew of my dad. I certainly learned a lot from him over the years and it's neat to see this sort of thing come full circle.

Craig

[sh00ter80]

Welcome to Cloudy Nights Craig,

I've been using Craig's software for about 6 months or so. It is really easy to use yet very robust when you get down to the nuts and bolts. I'm a regular in his group on Yahoo, what he says about a "sales pitch" is absolutely true. His software is top shelf and 9 times out of 10 if you have a legitamite issue with the software and it can be fixed it is done within the next version update.

It's great that you are on this forum to share your thoughts about AP, its direction and explain its complicated theories in a clear easy to understand form.

Thank you and welcome.

Bob
74°59’72.17”W 41°14’94.25”N
Hardyston NJ

[auriga]

Introduction to Fishing For Photons

By: Craig Stark

"Before we dive into the meat..." Eh?
Bill Meyers

[dwang]

Welcome to Cloudy Nights. Hope to hear more from you.

[quantumac]

By the way, I didn't mention it before, but I noticed the article is filled with strange characters, at least from a Safari/Mac OS X point of view. Looks like the breaks between sentences are a capital "A" with a caret on top. Also, quotation marks look similarly strange with a lower-case "a" followed by an epsilon character.

[Midnight Dan]

I see the same thing with the caret over the capital A's.

-Dan

[telstar9]

Great read.

[starbob1]

Thanks Craig for your help and contribution to this hobby.Your work is outstanding.I am just now getting into guiding and PHD software.Hope to read more from you.BOB

[Craig]

I'm working with the Mike Loffland on the odd characters. Things got lost in translation a bit. In general, those are quote marks. So, you'll have things like 8" f/5, etc. FWIW, I've put PDFs of them up here:

http://www.stark-lab...s/articles.html

Craig

[Psyire]

Great article! I enjoyed the read & am looking forward to the next installments.

[bill w]

great article craig
look forward to many more good reads

[Tim Gilliland]

Craig, I can't thank you enough for P.H.D. guiding. I am looking forward to your articles. I expect to improve my images with their help.

[Heine DK]

Thanks Craig for sharing your passion for astronomy here on CN and a big thanks for sharing your great software (PHD guiding in particular) for free.

Your history and background has many similarities to my own journey to astronomy. Early interest in astronomy, playing around with old dusty telescopes in high school, studying astrophysics at the university but ending up becoming an engineer.
A colleague of mine unpacking a meade N6 and Lxd75 at the office and showed me PHD guiding. This brought me back to the hobby again.(thanks Mark). Last spring I bought a 10" newton on a EQ6Pro to pair up with my DSLR. My first long exposure PHD guiding completely blew me away. Ever since I have been hooked. It's just amazing what is possible with todays equipment.

Thanks for helping making astro photography so accessible.
Looking forward to your future articles here on CN.

[Barry E.]

Craig,
A discussion has come up about a quick, yet accurate, way to analyze our raw images in the field to answer questions like, "Should I shoot 5m subs @ ISO1600 or 10m @ ISO800?". Theory aside, we are trying to determine a quantitative way to check the SNR of a given image that doesn't involve dark frames, spreadsheets, graphs, etc.

Since you say that SNR=Mean/StdDev, we agree that since this information is readily available, we can use it to analyze an image. But, WHERE in the image to use this formula is the question. We've identified three important areas of interest for a given image: Background, Strong DSO area, Weak DSO (transition) area. We could calculate the SNR of each of these areas and just average them, but the background should have no signal, so it really doesn't make sense to include it in the "goodness" number for the image.

Do you have any input into how to analyze a given image for SNR that is straightforward enough to allow us to make decisions in the field?

It would also be good to have an algorithm that is consistent enough to allow us to analyze our imaging over time to see if a given change was beneficial or not. Or to be able to compare our images to a friend's.