Pleiades wide field

TidaLpHasE · #1 01-10-2006, 10:28 AM

X marks the spot, nearly.

Took this today with the 5d, 50mm at f3.2, 390 seconds ISO 800, single image.
Not sure what the red neb is, it shows up nice though.

Now why couldn't those sats collide in the frame

iceman (Mike) · #2 01-10-2006, 10:49 AM

Wow, now that is a wide field.

There's really horrible compression artifacts though - how are you reducing it to websize?

Beautiful image Trevor.

Lester · #3 01-10-2006, 12:15 PM

Nice image Trevor,

the red nebula I think is the California Nebula

Octane (Humayun) · #4 01-10-2006, 01:17 PM

Trevor,

Those diffraction spikes are all mangy and the red smear are bleeding pixels.

The camera's no good, I think you'll have to offload it to me for nothing plus postage.

Wonderful image, as per the norm!

I believe Lester is correct, it's the California Nebula.

Regards,
Humayun

[1ponders] (Paul) · #5 01-10-2006, 02:28 PM

Busy spot over you place for spy satellites last night hey Trevor

Nice shot though, shame about the compression. Ditto to what Mike asked, how do you resize?

Can anyone identify the small open cluster to the right of The Pleiades in almost a straight line from the CN through the Pleiades? There is a satellite track going right through the middle of it. I've looked in SN and can't seem to find anything relating to it. It's not the Hyades as they are to the righ and up from The Pleiades.

matt · #6 01-10-2006, 02:57 PM

OK... for my own enlightenment...

can someone please point out the compression artefacts which folks are referring to???

I'd like to know what they look like so I can identify 'em myself in my own images.

Image looks OK to me

h0ughy (David) · #7 01-10-2006, 03:49 PM

Quote:

Originally Posted by TidaLpHasE

X marks the spot, nearly.

Took this today with the 5d, 50mm at f3.2, 390 seconds ISO 800, single image.
Not sure what the red neb is, it shows up nice though.

Now why couldn't those sats collide in the frame

LOL awesome shot!!! lots of activity there, look at all that neb stuff in the image wow

.

janoskiss (Steve H) · #8 01-10-2006, 03:54 PM

Quote:

Originally Posted by matt

OK... for my own enlightenment...

can someone please point out the compression artefacts which folks are referring to???

I'd like to know what they look like so I can identify 'em myself in my own images.

It's hard to describe. If you look closely, there aren't many well defined stars but mostly noise. If we could compare with the uncompressed original it would be obvious.

ballaratdragons (Ken) · #9 01-10-2006, 04:30 PM

Niiiiice!

4 Satellites in the one pic too!

That small cluster to the right is the 3 stars HIP 16891, 16924, 16985, and a few very very faint stars around them.

Star Map below shows the cluster.

ballaratdragons (Ken) · #10 01-10-2006, 04:54 PM

and a wider view

[1ponders] (Paul) · #11 01-10-2006, 05:28 PM

It came up well in the photo then.

I count 5 satellites

Calin · #12 02-10-2006, 01:11 PM

Quote:

Originally Posted by matt

OK... for my own enlightenment...

can someone please point out the compression artefacts which folks are referring to???

I'd like to know what they look like so I can identify 'em myself in my own images.

Image looks OK to me

Hi Matt,

An easy was to determine compression artefacts is to move closer to your monitor (very scientific) and eye-ball the image close up, you can easily see the 'mess' of poor compression compared to say other images also compressed (using different software) when viewing close up. Poor compression looks more like a mosaic of approximated colour and shape - after a little while you can pick this out without getting right on top of your monitor by just looking at the image from the usual distance. As my art teacher use to say many moons ago - "anything looks good when your standing 20 feet away and can't see the detail" ... she wasn't convinced I meant my art work to be veiwed from another room, preferably in the dark.

+

=

matt · #13 02-10-2006, 01:17 PM

Cheers Paul.

Nice to hear from you.

I think it'll make more sense when I can do something of a "compare and contrast", but I think I understand where you're coming from

fringe_dweller · #14 02-10-2006, 03:19 PM

thats a beauty Trevor, looks like your gettting there with tracking

man, stack several of those (minus sat's) and whoa!

spearo (Frank) · #15 02-10-2006, 03:59 PM

I like the shot, with the sattelite trails!
frank

spacezebra (Petra) · #16 02-10-2006, 09:43 PM

I agree Paul

Being new to this - I would like to see a compare and contrast too.

Cheers Petra

Quote:

Originally Posted by matt

Cheers Paul.

Nice to hear from you.

I think it'll make more sense when I can do something of a "compare and contrast", but I think I understand where you're coming from

TidaLpHasE · #17 04-10-2006, 01:35 PM

G'day all thanks for looking, and the nice comments.

Mike i have tried 16 and 8 bit tiff to jpeg in pscs2, also in m$oft digital image pro to resize my images.

I think the problem is cutting a 50-70 mb image down to 150k, and doing that without any jpeg artifacts seems a no go for me anyway.

Thanks for the i.d. Lester

O.K. Octane it's a deal, worked out postage to your door 1st class at $5500, not including insurance

Well spotted Paul, i have way overprocessed this image though, so it isn't as noticable in the normal image.

I have uploaded a higher res image here http://www.southernblueastro.com/M45%20wide.jpg

Only slight adjustments have been made to this one, about 1.5 meg.
should notice the difference in quality between the 2 pics.

Thanks again all for your comments.