Jump to content

NLCbanner2024.jpg.2478be509670e60c2d6efd04834b8b47.jpg

Orion Nebula - Single Shot, AZ Mount

theodoros1978

By theodoros1978
in Imaging - Deep Sky

Recommended Posts

RikM

RikM

Posted
Posted

Incredible shot for a single exposure on a tracking Dob. Hat's off....

Now you just need to take 20-30 of them and a bunch of darks and flats, throw them into Deep Sky Stacker and you will be able to pull out loads of faint nebulosity.

Welcome to the dark side.

Link to comment
Share on other sites
theodoros1978

theodoros1978

Posted
  • Author
Posted

I believe for a single shot it picked lots of detail. Take into consideration that i was on a city light sky, moon was setting and near the sea plus the AZ mount which kind of limits exposure time.

My camera is a Pentax K-x, not modding, no filters - out of the box. I took few of these shots and maybe i will stack later on, however i really like the beuaty of single shots.

Link to comment
Share on other sites
Brumtaffy

Brumtaffy

Posted
Posted

Really impressed by this image! I would though, as I'm dyed in the wool Pentax too :)

Pentax get overshadowed by the marvellous support there is for Cannon (esp. modded ones) in the Astro world/community. I want my DSLR day and night, though :)

I just moved up from a k200 to a k5 and was wooed into also buying the 0-GPS-1 unit. This allows the GPS data 'in' (via a small hotshoe attachment) to move the CMOS, allowing exposures of up to 5 mins on a fixed tripod (dept. on dec of object).

This is a single shot with a 200mm lens, on a tripod, 60sec, f8, ISO 100. Not nearly as detailed as Theo's, but this is a cropped image. The device is really good for wide field stuff too.

Pentax :) Pentax :)

:)

post-28834-133877690629_thumb.jpg

Link to comment
Share on other sites
theodoros1978

theodoros1978

Posted
  • Author
Posted

The 0-GPS-1 unit is awesome, too bad is not for K-x, i think k5 and kr only. I would try to image milky way shots if i had this unit :)

Pentax's marketing and support is not that good as Caninikon but they make really good DSLR's, check in dpreviews for comparisons.

thank you guys for comments. when weather is clear i will try to capture the horsehead nebula with my AZ setup.

Link to comment
Share on other sites
Superewza

Superewza

Posted
Posted
Sorry to be numb, but why does pushing up the ISO help so much?

The k5 can, apparently, go to very high ISO without too much noise creeping in. I wonder, then, what optimal ISO might be? I'll just have to have a play! :eek:

800 1st!

ISO is (basically) sensitivity to light. A low ISO, say from 50-100, would be your eyes adapted to a bright afternoon. ISO 400 is roughly mid evening/twilight, 800 would be a dark room and 1600 and above are after you're eyes have been adapting to the darkness for a good quarter of an hour. It works in stops though, it's not a linear scale. ISO 102,400 is only two or three stops above 3,200. If i understand it correctly, one ISO stop is equivilant to one aperture stop, so an image taken at ISO 100, f2.8 would be 'the same as' an image taken at ISO 200, f4, Going up or down one stop should be the same as doubling or halfing the amount of light light.

A higher ISO means fewer photons are needed to make the full image. But astrophotography is all about light - and thus also sensor size. If you have a tiny mobile phone camera sensor then very few photons are going to hit it, a webcam sensor is slightly better, a DSLR sensor is huge by comparison. 35mm film is a world away, MF a world away from that and LF is just the holy grail.

*might not be entirely right, it's late and i'm tired :D

Link to comment
Share on other sites
JimStan

JimStan

Posted
Posted

Well, Medium Format and Large Format cameras are probably wasted on the typical telescopes available to the amateur community. The reason for this is that the projected light cone will not cover the entire sensor of those larger cameras, and the result is the well-known "vignetting", that shows up as a falling off of light in the corners of the image. Some techniques and software can be used to minimize the effects of vignetting, but it is quite difficult to remove the artifacts completely.

Jim S.

Link to comment
Share on other sites
Superewza

Superewza

Posted
Posted

I think sometimes vignetting is a good thing, especially when you're meant to be focussing on an object in the middle of the frame. Would probably go with 6x6 though. What are the calculations for coverage?

The fact that it is probably film also means it has a much higher resolution, so even for the same size you could, with the right equipment, end up with a much larger print.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.