Horsehead(IC434) and Flame(NGC2024)

Oleg Novoselov

2795558

Deep Sky

Nov 18th, 2025

1012

NGC 2023NGC 2024IC 431IC 432IC 434IC 435

Resolution:: 2887x2831 px
File size:: 1857 KB

Show astrometry on hover

Photo description / processing

Finally tried the Samyang 135, which I modified back in the fall. I was very surprised by the spikes on Alnitak, it turned out the aperture was at 2.2. Actually, this is a mix from two filters: 7 frames with OPTOLONG L-eXtreme 2.0 and 10 with Optolong L-Ultimate. The difference is noticeable but not that significant. You can view and download it here, there are 7 frames each, the file names include the filters and exposure time. https://cloud.mail.ru/public/DfTu/TpXSJ8UG1

Technical information

Telescope/Lens: Samyang 135mm f/2 ED UMC
Camera: ZWO ASI676MC
Mount: JUWEI 14
Guide Scope: 30mm Finder
Guide Camera: Datyson T7C
Software: N.I.N.A., Pixinsight, Adobe Photoshop

Location: Екатеринбург, район озера Глухое.,, Россия

Light pollution

Orange, Bortle 6 zone

Date taken: Nov 16th, 2025

Exposure

17 × 180″ · ISO/Gain: 180 · OPTOLONG L-eXtreme 2.0 · Nov 16th, 2025

Total exposure: 51 m

Comments

UrmasX

To prevent spikes from appearing, if you need to stop down the aperture, you can screw rings onto the front.
It just seems like the "final" ring needs to be as close as possible to the lens. I haven't gotten around to testing this setup yet.

Nov 18th, 2025

Oleg NovoselovReply to UrmasX

I know this and have done it on previous samyang lenses, cutting a ring from plywood down to f/2.9, and there were no spikes. But back then, I needed to stop down the aperture because there was an issue with the stars. In this particular copy, the stars are almost perfect, so there's no point in stopping down the aperture.

Nov 19th, 2025

dmclReply to Oleg Novoselov

This lens allows easy removal of the front lens group—just unscrew a single ring from the front. Once this group is taken out, you can install an aperture diaphragm in the same position as the original one. There's a section about this modification at the end of this article: https://dzen.ru/a/Zn4-V-k1ZBytPJgn

Nov 19th, 2025

Oleg NovoselovReply to dmcl

Thank you, I've posted the link on the forum.

Nov 19th, 2025

Oleg NovoselovReply to Oleg Novoselov

in the topic Samyang 135mm f/2 ED UMC Four Thirds (Olympus 4/3)

Nov 19th, 2025