Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
03-09-2019, 07:17 AM   #1
Forum Member

Join Date: Jan 2008
Location: Dorset
Posts: 63
Sigma 8-16 for star photography?

I realise the Sigma 8-16 is a bit slow but is it a complete loss for star photography?

03-09-2019, 07:34 AM - 1 Like   #2
normhead's Avatar

Join Date: Jun 2007
Location: Near Algonquin Park
Photos: Gallery | Albums
Posts: 37,082
QuoteOriginally posted by Arbalist Quote
I realise the Sigma 8-16 is a bit slow but is it a complete loss for star photography?
I've used it before, but my star photography is pretty primitive, and I've bought the Rokinon 14 2.8, which one astro-photography site deemed the best astro-photography lens ever for all systems, not just for Pentax. I just thought, "it's not that expensive, give yourself a chance."
03-09-2019, 09:29 AM   #3
photoptimist's Avatar

Join Date: Jul 2016
Photos: Albums
Posts: 4,529
No lens is a complete loss for star photography but lesser lenses require darker skies, longer exposures, more stacking, more post-processing, and tracking mounts to get decent images.

One major issue with astrophotography is that the physical aperture (focal length divided by f-stop) really matters in terms of bring out the stars against the backdrop of the sky. By that measure the Rokinon 14/2.8 gathers nearly 8 times as much star light as the Sigma 8/4.5.
03-09-2019, 10:52 AM   #4
Loyal Site Supporter
Loyal Site Supporter

Join Date: Jun 2009
Location: Tumbleweed, Arizona
Photos: Gallery | Albums
Posts: 5,552
No, nothing is ever a complete loss. What you are doing, is essentially trading Field of View width, for aperture (collecting light). There are a number of things that you can do to recover. Bottom line is that with astro, collecting light is paramount, because there is so precious little of it from the stars (with no moon).

Take a look at this website Using - crop: 1.5, megapixel: 16, focal length: 8, pixel tolerance: 4 you can get 20seconds of exposure. Just lock the mirror up and using an external shutter release, just lock-it in continuous and take a number of images back to back. Then use Sequator (free download) to stack them.

You can also use the O-GPS1 startracer and get up to about 60 seconds of exposure. You can also stack those images too.

There are ways around the limitations. You will just essentially get dimmer stars, and these are ways to gather additional light to make them brighter.


  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
k-mount, pentax lens, sigma, slr lens, star
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
Thematic Post & Discuss Your Astro Tracer Star Trails & Star Shots wtlwdwgn Mini-Challenges, Games, and Photo Stories 48 2 Days Ago 01:47 PM
DA Star 16-50 power zoom contacts Daedbird Repairs and Warranty Service 2 12-24-2017 01:35 PM
Night Star Bright Star Night AussieTrev Post Your Photos! 4 03-28-2017 03:58 AM
Shootout #2 - DA 15 Ltd / Tamron 17-50 @17 / DA* 16-50 @16 / Sigma 10-20 @16 EarlVonTapia Pentax SLR Lens Discussion 4 06-23-2013 10:17 PM
Star light Star bright Scootatheschool1990 Monthly Photo Contests 0 07-26-2012 06:29 AM

All times are GMT -7. The time now is 12:25 PM. | See also:, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]