Tuesday, October 28, 2008

More on MMV Project

I'm learning a great deal from this project.

More to be updated

Monday, October 27, 2008

Email on MMV project

Today I emailed prof. Miloslav Druckmuller about his stunning eclipse images and asked him if he can share his techniques. This is the email I received:

Dear Paul,

I am a daughter of prof. Miloslav Druckmuller and I cooperate with him on the MMV project. He forwared me your email.

The image on the web address you sent in the email, was quite good. I think, we can make a good corona image from that. We have experience with processing images from Canon 350D, it's a good camera for eclipse images.

Do you have CR2 files? These are necessary, we cannot make any good results from JPG's.
And what ISO setting did you have? We need ISO 400 maximum.

Do you also have flat-field, dark-frame or bias images? If not, take several tens of bias images. They are images taken with lens covered with a cap at the shortest exposore the camera enables. Take them at a similar temperature which was at the observing place.

Where did you obsere the eclipse?

Send us the images and the calibration images on a CD or a DVD. However, I cannot tell you when we will process the images. I still haven't processed all our images and we still have excelent images by other people to process. I think we will process them in several months.

Best regards
Hana Druckmullerova

.......NOW I'm really impressed

Another emailed that follows up:

Dear Paul,

please send me the images to
Czech Republic

Please attach a file with descriptive information like the author, location with coordinates, camera, optics, name of the observing place and any other information like the observing conditions.

I know that you have sent me almost all these information, but we really have many CDs and DVDs from various observers and eclipses and this will help us to have the data organized. It would also help me if you attached a file with a list of all eclipse images with their exposures and the time when they were taken. Either the time from the EXIF information or even better how many seconds after the second contact each image was taken. This would save me some time when processing the images.

Best regards
Hana Druckmullerova

PS: Could you please use a post stamp on the package? I do not have any Chinese stamp. Do you have Chinese post or a separate one? :-)

I'm suddenly so excited to be able to participate in such kind of world class multi national scientific project XD

Monday, October 20, 2008

Suddenly realized...


and then I found that it is useless...

Monday, October 6, 2008

Deepskystacker -- Bayer Drizzle vs Non-Bayer Drizzle

The following images are acquired by:
Modified 350D, 135F2L @ F2
Exposure: 5x4min @ ISO400 + 5x4min @ ISO800
Registering and stacking: Deepskystacker

There is a feature in the software called Bayer Drizzle which I haven't noticed before. According to the name of teh feature itself, its function seems to be performing a calculation which allows the Bayer grid of a DSLR to maximize its resolution so that it can perform on par with mono colour CCD. (I'm a total idiot on this kind of stuff.... for the detailed explanation on how it is done please refer to the help manual.. or if i have time I will try to understand it and talk about it later)

To activate the feature you can go to the Raw and DDP settings and check the box "Bayer Drizzle"

So this is what it is like:


Bayer Drizzled

It seems that I had a problem with the little blue and red squares after the stacking... and Wei-Hao Wang explained to me the reason of the problem is the brightness difference of the raw frames. Then I stacked the ISO 400 and 800 frames seperately and then combined them together and got the following result.

Bayer Drizzle version 2

The square pattern is gone and the stars are much tighter than the original... nice!