DSS text and master dark files.

[Larry 1969]

So, I've been going through my data and trying to organize it all and I found all these text documents in along with my raw data.
I deleted them all (quite time consuming). I think DSS puts them there after "registering" them? Not sure why though.

I have folders titled by the object then sub folders titled by date, sub folders within them titled raw, darks and processed image.
I noticed DSS also creates a "master dark" that gets stored as well. Can I save these "master darks" and discard the individual dark frames?

How do you guys and gals do it?

Thanks!

Larry

[bladekeeper]

Data organization is definitely an individual thing. I'm not especially organized. Mine, right now, is pretty much organized by date. Definitely need to get that arranged in a more optimal fashion.

As for the DSS text files, if you delete those, and then you choose to go back and restack a set, you will need to re-register. Not a deal killer, though.

Yes, you may keep the master dark/flat/dark flat/bias and delete the individual subs.

[Larry 1969]

Thanks Bladekeeper!
I'll work on that tomorrow!

Larry

[bobharmony]

Larry, before you delete all your darks, consider that you can reuse them on other images that have the same ISO/exposure length/temperature settings. They do have a shelf life of a few months, depending on how quickly your camera changes characteristics like number of hot pixels, etc.

I keep my darks in a separate folder structure than the lights and flats, and I try to collect them at times other than when I am set up and imaging. It may be a small thing, but it allows for more time collecting lights when the weather is good. And they are ready to use when I am ready to process.

For images that I have stacked and created a master dark for, I save the master dark and use that if I decide to re-stack at a later time.

Bob

[Larry 1969]

Thanks Bob!
So, if I want to re-stack an image with DSS I can add all the light frames and then just the master dark?
I don't have to enter all the individual dark frames? This applies to a master bias as well?

Larry

[bobharmony]

Thanks Bob!
So, if I want to re-stack an image with DSS I can add all the light frames and then just the master dark?
I don't have to enter all the individual dark frames? This applies to a master bias as well?

Larry

Larry, that is right, once you have built master bias, darks, and flats ( if you are using flats), you can use those masters if you go back and reprocess the lights.

For bias frames, I create a master bias out of a couple of hundred individual bias frames, and use that master for all image processing over the next few months.

Bob

[Larry 1969]

Larry, that is right, once you have built master bias, darks, and flats ( if you are using flats), you can use those masters if you go back and reprocess the lights.

For bias frames, I create a master bias out of a couple of hundred individual bias frames, and use that master for all image processing over the next few months.

Bob

Thanks again Bob!
Just so I have this right.
If I want to re-stack an image in DSS I would click "open picture files" and enter all my raw data. Then click "dark files" and add my single master dark from that session. Then click "offset/bias" and enter my single master bias?
I can use that bias for a few months but the dark frames should be taken each session? (As I understand it, dark frames are temp sensitive while bias is not so much?)

Larry

[bobharmony]

Larry

You are correct on the master bias. The Master created by DSS using one set of short images (I use 201 images at 1/8000 second and ISO 800 (to match my lights and darks)) can be used for several months for any new data or target.

You are correct that dark files temperature should match the temperature of the lights and be stacked together. For me, I fire off a few darks early in the evening that are the same length and ISO as my lights while I am tweaking balancing and polar alignment. My usual exposure time is 180 seconds, so I take darks of that length and pause a minute between darks to allow the sensor to cool as it does between lights while PHD2 is dithering and allowing the scope tracking to settle. If there is time at the end of the session, I will collect another set of darks in the same way. This will give me 10-25 darks to use with that nights lights.

Another method for dark capture is to set up the camera on days or nights that may match the ambient temperature over the next few months on a day when you aren't imaging and start up a sequence of darks that can serve as a library to pull from when stacking a set of lights in DSS. Selecting a group of darks that have the same temperature reading as the lights allows you to spend more time when the sky is clear collecting lights, which should make the final image less noisy. Once you have created a master dark with a certain temperature setting, you can use that master to restack the lights later on, or it can be used if you have another imaging session where the lights are in that same temperature range.

It has been pointed out to me that the "camera temperature" reported by Canon cameras does not reflect the actual sensor temperature, and may not be reliable for matching darks and lights. My experience with the 60D is that when I collect lights and darks on the same night under the same conditions, and provide time between images for the camera to cool, the temperature reported during light and dark capture trend very close to each other, so my tendency is to rely on the camera temperature readout to match my lights and darks. Your mileage may vary - if you feel the combination of a certain light and dark set result in excessive noise, feel free to experiment with other temperature combinations to see if they yield less noisy results.

Bob

[JayTee]

Hey gents,

This really does belong in the Image Processing subforum. Look for it there. By tomorrow.

Cheers,
JT

[Larry 1969]

Sorry JayTee.....

Larry

[Graeme1858]

I never delete anything and my hard drive is full!!! You can however, sort the files in a folder by type and then delete the text files in one swift move.

How I file stuff has evolved into Target Name/Date/Type(Lights, Darks, Bias, Flats etc) Then PIPP creates a sub folder, AS2! creates a sub folder and I usually finish off with Gimp and save processing attempts in Final Images/Target Name/Date/Type.

I'll be following this thread, wherever it goes, looking for improvements to my system!

Regards

Graeme

[Larry 1969]

I just got started in this so my data set isn't too extensive. Plus most of it is garbage compared to what others are getting so I may just delete most of it and start over.
I just got a new computer. I told the wife the old one was just out dated but, secretly, it was because DSS and StarTools would run out of memory!
I captured my best subs ever 2 weeks ago on M27 and I can't wait to see what I can do with it! :cool:

Larry

[JayTee]

I knew I was forgetting something -- this thread (topic) just got moved to "Image Processing".

Cheers,
JT

[Larry 1969]

I thought you were sleeping! :asleep: