Orion Arm Panorama

[gregbradley]

I did a series of nightscapes about 3 weeks ago.

A lot of air glow was present at the time.

This is with a new Sony A7r3 using its pixel shift technology which is not dissimilar to LRGB imaging like we do with deep sky objects. It takes 4 images each one moved one pixel so each colour gets al 4 pixels when combined.

Sigma Art 14mm F1.8 30 seconds tracked at ISO6400. 3 panels.

http://www.pbase.com/image/167076502/large

Greg.

[zardos123]

thats some serious air glow, it will be interesting to see some more from the pixel shift, i find it pretty good. Is the Sony stuck at a maximum of 30 second subs like the Pentax, I have sent a request up stream to ricoh asking for a software fix

[gregbradley]

Yes it is limited to 30 seconds.

Not a problem for me as I have settled on 30 second subs and doing 4-6 subs and stacking them and either using a fast lens or a longer lens with a reasonably fast aperture.

I see a K1 mark 2 is out with handheld pixel shift now.

Greg.

[gregbradley]

Here's another one:

Sony A7r2 Zeiss Loxia 21mm F2.8 tracked, 5 panels of 4-6 images each.


http://www.pbase.com/gregbradley/image/167079977/large

Greg.

[Atmos]

You've got some really nice panoramas going Greg.
What are your thoughts on the correction of the Sigma Art 14mm?
I've had it on my short list for a landscape lens for a while and one to play with for the up and coming Milky Way season.

[zardos123]

I will wait and see how effective it is, i am impressed with the loyalty pentax/Ricoh are showing those invested in the system , being able to send the k1 in to get the body upgraded to the mark 2 at 20% of the cost of a new body is awesome :thumbsup:
and another nice shot, will see you at SPSP?

[gregbradley]

Its fabulous. A bit of coma right in the corners wide open. I did some experimenting and was able to focus on the worst corner and got round stars all over. Tried that again at my dark site and ended up with a night of out of focus stars!

Its a very good lens and deserves the crown of best ultra wide Astro lens.
I did have to return my first copy as it wasn't good enough in the corners (much worse on one side than the other). The 2nd copy is quite good and pretty even left and right.




That is a good deal. 20% is very cheap. No sure about SPSP. When is it?

Greg.

[zardos123]

10th-13th may
registrations open now http://www.asnsw.com/node/712

[Ryderscope]

Hi Greg, I like the way that these images have turned out.

With the composition process, are you saying that you produced a 5 panel mosaic comprised of 4 - 6 images per panel? I have thought about doing this and figured that you would have to limit the number of images per panel otherwise the sky would have moved too much against the foreground by the time the last panel was taken.

[RickS]

Beautiful images, Greg!

[gregbradley]

Hi Rodney,

With an ultra wide lens it does not seem to be too much of a factor. But you will get a blurry background so unless you want to blend a mosaic of landscape only which is not tracked (I have found this to be very difficult so far) then it is best to limit the number. That's why a faster lens is helpful here. Getting a low noise shot quickly is important.

Greg

[gregbradley]

Thanks Rick. I enjoy taking these types of images. Once the scope is running and doing its programmed exposure run there is plenty of time to do something like this. It gets harder in winter though!


Greg.