Newbie attempt at Saturn

universe24 · Post by **universe24** » Fri Nov 14, 2003 6:45 am

adree wrote:I think the image was taken from a 10" teleport scope

10" scope impossible to take such small Mars. Unless it has been resize. If not, it should be as big as 2" diameter ball when we see on monitor.
Any barlow used to take the Mars image? Or it just prime focus?

universe24 · Post by **universe24** » Fri Nov 14, 2003 6:55 am

weixing wrote:Hi,
I think the image is the result of excellent image processing.... It is nearly impossible to take a image like this without any image processing. Anway, the image is very detail, but may be a bit too detail that look unnatural...

By the way, I always wonder how you guys manage to process the image... it just incredible... May be you guys should post some article or tutorial showing us how to do image processing

Image processing is too subjective. Everyone got their different way on image processing. Some people think that details is more important than just look natural and some people think the other way round.
Actually if the weather is good, the main part in image processing is to stack as many frames as possible to reduce signal of noise. Further adjustment like colour balance, contrast, brightness and others is too subject to individual decision.
Anyway, before you process any astro images, please calibrate your monitor screen to get the optimum contrast and brightness.

elton · Post by **elton** » Fri Nov 14, 2003 9:23 am

it was taken at prime focus 1270mm focal length. tried using a barlow but the image was impossible to find. agreed it looks a little artificial but I would give Sam the credit of coaxing out quite a bit of detail from a small image. The point i was trying to make is that it is possible to image from an un-driven mount (even a dob). no guiding was done, we just imaged as Mars drifted across the ccd. The short exposure time of the toucam allowed for rather sharp images at this focal length. At higher focal lengths, it gets quite impossible to focus and find the object and you can expect that the image smearing caused by using an undriven mount to be greater.

dew · Post by **dew** » Fri Nov 14, 2003 11:35 am

Sam Chng tried once to use the toucam on my teleport to image mars. Even at f5 (1250mm), placing the image on the chip was tough but we managed to grab a few dozen frames. Focus was dubious. I tried to guide by manually moving the dob with some success but we ended up letting the image drift across the ccd while imaging. This is the result of his image processing. Still possible i guess...

wow.. i gotta say, thats a really really great pic of mars! its amazing! just for comparison, heres one i took in august with my ETX-125 and nikon 4300 digital camera.. its a stack of about 90 pics i think.. and had some very amaturish processing done by me on regristrax.. any comments, criticisms and suggestions are most welcome, i would love to learn more and improve my photo quality..

actually sam chng was the one who taught me how to use the basic functions of regristrax.. thanks sam!

Post by **Airconvent** » Sat Nov 15, 2003 12:52 am

dew wrote:wow.. i gotta say, thats a really really great pic of mars! its amazing! just for comparison, heres one i took in august with my ETX-125 and nikon 4300 digital camera.. its a stack of about 90 pics i think.. and had some very amaturish processing done by me on regristrax.. any comments, criticisms and suggestions are most welcome, i would love to learn more and improve my photo quality..

actually sam chng was the one who taught me how to use the basic functions of regristrax.. thanks sam!

wow...if that's amatuerish, then I don't dare show mine!
I've taken quite a few shots on my ETX105 with the same Nikon 4300 camera but the results in ANY setting is a relatively blurred blob although you can make out the polar caps and surface features.
You can see my even more amatuerish attempt here :

www.pbase.com/airconvent

Yours has one of the finest details I have seen taken by an ETX. If you don't believe it, check out all the attempts by other ETX users around the world posted on www.weasner.com (The Mighty ETX Website).
Out of curiosity, can you also post one raw unprocessed image?
I'm thinking if I take 90 of those blurred blob shots, and stack it, can I achieve the same effect?
Do let me know when you will try again in Dempsey...want to drop by and learn from the "ex-student" of Sam Chng....

rich

dew · Post by **dew** » Sat Nov 15, 2003 1:41 pm

hmm.. there seems to be a problem with my first post.. the first paragraph was supposed to be a quote from eltons first message.. just to clear any possible confusion..

I'm thinking if I take 90 of those blurred blob shots, and stack it, can I achieve the same effect?
Do let me know when you will try again in Dempsey...want to drop by and learn from the "ex-student" of Sam Chng....

you can stack your photos but i think gotta use photos taken within about 7-10 min max so you wont get a blurred image due to the planet rotation of mars.. actually what enabled me to take so many shots was the camera remote i bought from chuang yee.. that was seriously one of the best investments i made.. with it i can take about twice as many photos in 2/3 the time as when i did without the remote..

anyway, elton i gotta say again, i think your photo is bloody amazing! i mean i actually prefer it to some of those from sky and telescope.. there seems to be some 3-D effect in it.. i mean it actually looks like a sphere, or at least thats my impression.. amazing!

eu-wen

dew · Post by **dew** » Sat Nov 15, 2003 1:44 pm

and heres the single unprocessed image you wanted rich..

universe24 · Post by **universe24** » Sat Nov 15, 2003 1:54 pm

This should be a very good Mars image when go through a certain process!!!
Could I see the final result?

Post by **weixing** » Sat Nov 15, 2003 2:02 pm

Hi,
For those who know how to use regristrax, can post some sort of tutorials on regristrax??? I try to use it, but the result was just bad...

Anyway, care to share with us the setting of the camera for your shot, such as resolution, shutter speed and ISO??? This will sure help us who are new to Astrophotography....

Post by **Airconvent** » Sun Nov 16, 2003 1:56 am

dew wrote:and heres the single unprocessed image you wanted rich..

holy cow! you mean you under-exposed all the images by so much? this must be at least a 1/750 - 1/1000 sec shot to be so dim.
heh heh, so you are the one who bought Chuan Yee's remote. I nearly bought one together with him (we bought our 4300 around the same time) when we went to buy a spare battery in sls but the $150+ price tag turned me off...
Already invested quite a bit on the digi-T, so do not want to spend too much more...

back to the photo, so you are saying that you kept on clicking for up to 70 images and then use registrax to merge them?

rich