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jsmoraes
27-12-2014, 05:34 AM
Spiral galaxy located in constellation Cetus that has nucleos crossed by a wide dark lane of dust and gas.
It is a binary system together with galaxy M77

GSO 305 mm - Canon T3 - 7 x 4 min (28 min) - ISO 800 - OAG - Skyglow filter - Coma corrector


note: clouds, focus and guiding (winds) didn't let me take many photos.

tonybarry
28-12-2014, 01:44 PM
Hi Jorge,

Nice galaxy, close to M77 but I haven't seen it before. The image you have posted looked more compact than M104 (the Sombrero).

Thanks for the image - I will have a look at it when the clouds go away from Sydney and we get to see stars again.

Regards,
Tony Barry
WSAAG

Marios
01-01-2015, 05:14 PM
Hi Jorge

Good effort however you will need to accumulate at-least 2 hours minimum to give these DSO's some detail. Id suggest a ISO of 1600 for galaxy's to increase that photon response.

How are you focusing you're camera??

jsmoraes
02-01-2015, 12:48 AM
With wich camera ?

Canon, for example, don't like too much time of exposition. The stars will be RGB saturated, showing all stars with only white color.

Actually, I think that too much time can be not good for any color camera. This situation is very different if you work with mono-camera and LRGB filters.

ISO 1600: It is not true that high ISO will enhance your capture. It depends from light pollution, sky glow, temperature, model of camera and others.

For my set and site of my observatory I have ISO 400 and 800 as the better ISO to use. I use ISO 1600, also, but only in special condition and with few targets.

Today, I am having much more noise in red channel than normally. With or without sense, I am thinking about the atmosphere condition at Atlantic near South America. It seems that I am having more intensity of iR or NIR radiations that are causing some influence in the result of my captures.

My last try with ISO 1600 - Horse Head published here, also - was terrible with this issue ! And only in red channel.


Many people ask about this. I use FWHM of BackyardEos and short capture to analyse the shape of star (round or not) and the single line in spikes. After this I always check the quality of the first frame of a session.

What happens here is refraction. As I am near of the beach I have much umidity and therefore much refraction. I use 10 frames for FWHM in BackyarEos, and I haven't a stable reading of FWHM. Maybe I must use more frames. I will try with 20 or 30 frames.

I tried mask, but it is the same for FWHM. You haven't a stable image to tell: ok, good focus !

Did you saw how Jupiter dances when we want to shot him ? Ok, the stars, with my set of equipment of 0,7 arcsec/px and my normal refraction, dance alike... or more !
An example:
http://astronomia-e-astrofotos.1069742.n5.nabble.com/file/n1069/RiguelCent_193335.00.gif

So my stars are more chubby and seems to be out of focus: http://astronomia-e-astrofotos.1069742.n5.nabble.com/file/n1069/riguelcent_rgtx.jpg

Some times, I see a good image ... a lucky frame. I think it is a good focus, but it is only a lucky frame !

I always try to publish the full resolution of my set. I crop the image to publish it. Therefore you can perceive any problem with the photo. If I reduce the photo, perhaps you will never will perceive the problems.