Wider Coal Sack

[xelasnave]

Thru the cheap but great in my opinion Nikon 70 - 200 lens a heap of 15 second exposures with no darks etc.
I liked the detail of the various dust lanes.
alex

[xelasnave]

Looking at the image here it really did suffer from my downsize.
but the original is beyond compare:rolleyes::D
alex

[raymo]

Good job Alex, although I personally prefer the cross upright.
raymo

[bojan]

Green.....

I rad somewhere the colour of the universe is pink-ish...

Beige actually.. see here (https://www.newscientist.com/article/dn2013-the-universe-is-not-turquoise-its-beige/).

[xelasnave]

Maybe this is better in detail...

alex

[xelasnave]

Thanks for the attempt to help me Bojan but the colour blindness prevents me even seeing a difference in many cases.
Blue can be purple or green can be brown..I just cant tell unfortunately.
I play with the colours until more detail jumps out..to me..which may not jump out for others..I dont know.

I try to get my daughter to help but I have exhausted her patience it seems.

I said somewhere else here today I am probably best just imaging in Ha so I get detail and dont mess up the colour.

alex

[xelasnave]

Which way is upright Raymo?
The thing rotates and stands on its head at times:D
But thank you for the encouragement I sure do appreciate your taking the time to do that.
alex

[xelasnave]

I was particulary trying to bring out that dust lane to the left in the photo.. I dont know if it has a name...but its the one on the left.
alex

[bojan]

North, by standard...

[bojan]

This is much better, even colour is closer

The dust lane is in Musca, NGC4372
http://www.irida-observatory.org/DSLR/Dark_Doodad/Dark_Doodad.htm

[PKay]

Get outa here mate!

I have never seen so many stars in a single image :eyepop:
It's like a beach of sand or something.

Incredible dude :thumbsup:

Sorry bout the eyepop, I thought it was cool.

[xelasnave]

Thank you Peter..the Deep Sky Stacker count was about 13000 stars I recall.
Please tell me do you see anything that indicates a problem with the lens..Its a $200( approx) Nikon 70 - 200 lens and well I really like the results I am getting but I am not sophisticated enough to see the flaws..Can you detect something that says spend $1000 on a lens to replace it.
alex

[raymo]

When its upside down I do a headstand to take the photo.:)

[xelasnave]

Thats ok for you nimble young fellas but not an old fella like me.
alex

[bojan]

No problems with lens at this scale...

Give us 1:1 crops from corners of the frame, any flaws will be visible there

[xelasnave]

Here is the image as it can out of DSS downsized to upload it only.
alex

[xelasnave]

The first is the left side and the second is the right side
alex

[bojan]

Yes... there is some coma at lower left, it could also bi some tilt - but all in all very good lens.

[bojan]

Oh yes... that one is almost perfect.

What could be the purple band at the bottom?
Mirror vignetting?

As to uploading... you can reduce the quality in jpg (higher compressing) while retain the size.
Also, forum will accept 1~2MB, and the image will be automatically compressed further, down to ~200kB

[JA]

Only one problem Alex:D, the price. Nikon's 70-200 ain't $200 ish.

Nikon's only 70-200 is the 70-200 f/2.8 (and more recent 70-200 f/4) which has existed/exists in various Full frame versions and depending on model is $2000-3500 new. Even second hand they are $1500-2000 depending on which model/age. You may mean the Nikon 55-200 or 55-300 or 70-300 which are all good lenses and designed for the DX / APS-c format. Unfortunately they are not in the same league as their fullframe friends the 70-200 f/2.8 VR or VRII or their predecessors 80-200 afs, afd, af, BUT they are extremely good and very sharp. I have seen remarkable images taken with some of these lenses (55-200, 55-300, also 18-140). I've also seen them coupled to an astrocam with great results.

Lookin' Good :thumbsup:

Best
JA

[xelasnave]

I use a little baffled dew tube as am am convinced it helps keep stray light off the lens and hopefully minimises reflections...it can however get in the way of the light coming in if its not on properly and the purple may be attributable to it being in the way.
Alex

[xelasnave]

Thank you JA for taking your time to educate me on the len pricing and performance.
Fortunately I am happy with things so far or not unhappy enough to go into $2000 bracket.
I am considering (today so this could change tomorrow) a Pentax full frame ca.era and noticed a lens around the $800 mark which I thought probably worthwhile when , if I buy that camera.
Its 50 to 200 I think and that range appealled because I really like wide fields ...the wider the better with the Milky Way.
What I would like to do some day is to narrow band a wide field as I think that could be something.
Plus I would like another camera maybe to poggy back when imaging thru say the 80 mm scope...it may cause vibration issues with two cameras clicking away but that is sort of the general idea.
Alex

[raymo]

Alex,If I, an octogenarian, am a nimble young fella, how old must you be
for goodness sake?
raymo

[xelasnave]

Well I am only 71 years old but I was born at a very young age.

My legs are a problem Raymo...I had a back problem which threatened to make me drive a wheel chair and although the operation was a sucess my legs still burn non stop and generally add a century on how I feel.

The numbness in my feet would cause me to topple if I tried your suggested acrobatics.

I could rotate the image in gimp which I should do to make you happy by presenting an upright cross:).

But I decided to stop processing a little while ago as I was in what may be my future home and observatory, a little shed that has a good power supply, but I looked up and there was a little snake in the rafters above me...it put me off so I packed it in and came down to the house.

I think its only a green snake but as I cant tell green from brown I work on the basis it could be a brown snake...and even a little one can kill you and I want to avoid that.
Alex

[JA]

I wasn't suggesting you were or should be unhappy with the lens. I think the 55-200 is a very sharp lens, that I have recommended with some other DX lenses quite a few times. My real point was only that the 70-200 isn't a 55-200, nor does it have the $200 ish price tag.



I think some of those Pentax DSLR models are excellent and the astrotracer function could be very useful in travelling light in the field by using a fixed tripod. Also their pixel-shift function (models?) can be useful for ultrahigh resolution still images. I'm not sure if it could be used well with the astrotracer function, but might offer some benefit on a tracked mount (test required). It would be wonderful to see this implemented in the other major brands as well.



I'm Not sure if you are referring to a new lens for your possible new Pentax or your current Nikon 55-200 DX lens. If you want a little more reach at the same quality level there is also a Nikon 55-300 DX lens. Also excellent and very well priced. Second hand they are almost for free :D

I don't recall if it was a 55-200 or 55-300 (EDIT: Just checked it was the Nikon 55-300MM F/4-5.6 AF-S VR DX), but Diego, one of our members here used one with an astrocam, motorised focus, filterwheel setup, etc, that was remarkable in nice tiny-ish stars, sharpness and lack of obvious abberation, just that given its relatively modest aperture for a 55mm lens (f/4) it would require longer exposure than your typical 50mm-ish prime lens.

I will see if I can link it for reference....
EDIT: see ......
http://www.iceinspace.com.au/forum/showthread.php?p=1342739&highlight=nikon#post1342739

Best
JA

[raymo]

I can sympathise with you Alex, I had a horrendous 175kmh motor cycle bingle some 57 yrs ago, which brought an abrupt end to my career of choice, and left me with chronic back and hip pain.
raymo

[xelasnave]

Thanks JA
That feature to follow the stars could be handy and I bet I could make a go of it with short exposures , high iso ( high iso is not as noisy as I remember...I use 1600 mostly now although I tried a 400 iso on Omega C the other night whilst waiting for the lobster to climb out of the trees...and 400 iso did not seem to offer any noticable benefit..yet I have to go back to it as I got tired up with the lobster neb and up to now forgot about the Omega images...I did stack them but the final image from dds did not hrab me because the center was burnt out...so I did not bother to process it...if it gets cloudy I may try..oh it is cloudy what a surprise.
I have had a few goes going up to 3200 iso and I think even the next up and those seemed ok...depands on what the noise is in the K1 (?) Pentax but static would be great.
I would lie to be able to demonstrate and encourage folk considering astro photograpy by demonstrating a relatively cheap entry level via camera and a tripod.
Alex

[xelasnave]

Wow 175 kph..I have never been over 165 on a bike...a road not dirt bike..moto cross was never over 110 in the straight...but I have come off at between 80 and100 kph more times than I can remember..pretty routine in moto cross and never broke anything fortunately.

And the funny thing at a track riders would have the same sort of crash in the same corner as would I ....they would get broken legs and arms but I never did...very sore but no broken bones.
Very lucky guy I am.
Alex