DSLR DSO Images

[JohnSadlerAstro]

Hi Guys,

In the book, 'Making Every Photon Count,' there's a list of good DSO imaging targets but it doesn't give the exposure or lens details for the pictures that are shown for each object. I'm wondering what DSOs would be the best ones to try to capture with an un-modded DSLR and a 200mm lens, with sub-exposures of less than 2 minutes. Does anyone have any suggestions, or any pictures, of bright DSOs that I can capture with subs of that length, as I'd really like to know what to expect out of that sort of equipment?

Thanks,

John   

[badger111]

Try M31 Andromeda Galaxy - Nice and bright

[baggywrinkle]

Are you using a driven mount or a tripod?

I usually would use 20 secs or less with a 35mm lens, the longer the lens the shorter the exposure if undriven.

If driven then ISO1600 and a good polar alignment to get above 1 min to 2 min.

Andromeda is nicely placed in the evening sky and the Pleiades are rising by 21:00 but a bit low until 22:00 or catch the Pleiades and M42 in the morning.

[Stub Mandrel]

I got rewarding results from M31 with 64 subs of 80 seconds each, ISO1600, 500mm f6.3 lens, unguided. No problems with 'unround' stars.

M57 and M27 will both show nicely using a scope instead of a lens with exposures of about a minute.

M33 and M101 both show up at such exposures, but I reckon 2 minutes will be needed to get decent results.

I have fairly high levels of light pollution too.

[D4N]

As a rule of thumb avoid emission nebulae with an unmodded DSLR as most of the light will be blocked by the IR cut filter.

Galaxies and reflection nebulae will be good though.

Quite a few planetarium programs will overlay field of view to help frame targets, Stellarium CDC and Sky Safari will all do this.

You could also use the online field of view calculator on the FLO site.

http://astronomy.tools/calculators/field_of_view/

Select your camera and enter the focal length of your lens. Select different targets to see how well they will frame.

/Dan

Sent from my iPad using Tapatalk

[Knight of Clear Skies]

I assume you are using a tracking mount? Your maximum exposure time will depend on the focal ratio of your lens and local sky brightness (light pollution and moonlight if it's up), if you overexpose then stars will start to blow out. From a dark site I can take 3m30s exposures at ISO 800/f4 without problems, but from around here I have to drop the ISO to 400 and reduce the time.

The Pleiades are a good target for a 200mm lens, nice and bright and containing reflection rather than emission nebulosity. Of the emission nebula M42 is bright enough to image with an unmodded camera and possibly the North America nebula too.

[JohnSadlerAstro]

Yes, I'm going to be using a driven Equatorial mount.

John

[laser_jock99]

M42 in Orion is bright enough to record some red without a modded camera. NGC7000 North America Nebula in Cygnus can also be picked up easily with an un-modded camera.

NGC7000 North America Nebula, Cygnus - 157 seconds, Fuji S5 Pro DSLR, Nikon 300mm F4, ISO800.