[kayasaman]

Hi all,

just wondering if anyone out there is doing deep sky astro work on the K1?


Having recently grabbed the K1 mkII mainly for night and astro imaging I am now starting to think about and research lenses and Go-To mounts.


Currently my thoughts are to go for either the William Optics RedCAT:

RedCat 51 APO - William Optics

or the Askar ACL200:

ACL200|ASKAR|Jiaxing Ruixing Optical Instrument Co., Ltd.-Jiaxing RuiXing optical instrument co., LTD


then later on go for something with further reach.


What mount would be a good one? So far I am looking at these -

Ioptron GEM28:

GEM28

Sky-Watcher EQ6R Pro:

Sky-Watcher | Sky-Watcher Global Website

Explore Scientific EXOS2:

Explore Scientific EXOS2-GT Equatorial Mount with PMC-Eight GoTo Syste ? Explore Scientific LLC


Ideally would like something portable as in backpack friendly (yes Astrotracer... I know lol), computer controlled, and that can take a payload of around 10kg/22lbs


Though I think with what I have in mind portability maybe wishful thinking as most of these guys come with a dedicated tripod, though fitting them into the trunk shouldn't be an issue


I also have gone through the indilib supported mount list: Telescopes
to see what is available to me. This is important as I only use Linux on my laptop so something that is only supported for M$ or Mac isn't gona work.


Anyway, just wondering if anyone out there can suggest anything??


Also it seems with these guys that the shutter release cables are for many other brands including Olympus and Fuji but Pentax seems to not be mentioned anywhere
- important if taking multiple 10 minute (or longer) shot sequences of stellar objects like planets or galaxies.

[ProfessorBuzz]

It's a fun hobby - the question is - What are you trying to do? Wide field astrophotography - milky way shots, extended objects like the Veil Nebula, or deep sky objects like galaxies and planetary nebulae?

Those scopes are too small for deep sky; the Red Cat is the better built of the 2. You need more glass to do anything useful. You might want to just start with Pentax lenses you own, and figure out which ones are sharpest. Then get yourself a better scope (100mm+ diameter).


I had an iOptron 25 and it was ok but the software in the hand controller was buggy; some of the gears/drive parts were mostly plastic. I sold it and don't miss it at all.
The EQ6 variants are solid and heavy; many suffered from backlash problems due to their belt drive, and so people have come up with modification kits. The newer versions are better.

I have no experience with the Explore mounts.
All this stuff is built in China, and quality is not good on much of it.

Good luck, have fun!

[kayasaman]

It's a fun hobby - the question is - What are you trying to do? Wide field astrophotography - milky way shots, extended objects like the Veil Nebula, or deep sky objects like galaxies and planetary nebulae?

Those scopes are too small for deep sky; the Red Cat is the better built of the 2. You need more glass to do anything useful. You might want to just start with Pentax lenses you own, and figure out which ones are sharpest. Then get yourself a better scope (100mm+ diameter).


I had an iOptron 25 and it was ok but the software in the hand controller was buggy; some of the gears/drive parts were mostly plastic. I sold it and don't miss it at all.
The EQ6 variants are solid and heavy; many suffered from backlash problems due to their belt drive, and so people have come up with modification kits. The newer versions are better.

I have no experience with the Explore mounts.
All this stuff is built in China, and quality is not good on much of it.

Good luck, have fun!

Thanks so much for the response. At present I don't have any Pentax lenses outside of the 28-105mm, the only other lens I have is the Samyang 24mm f1.4 which I got for wide angle sky shots to be used with Astrotracer. Though as of now I seem to be using for everything :P

At the moment I just want to get into the subject and learn before buying anything larger.

My Pentax kit is new and I don't even have a photo tripod yet so I'm just looking and studying right now.


I'll probably go for the RedCAT lens as my next lens which can also double up as a terrestrial telephoto on the odd occasion that I need one - I prefer wide angle scapes in general so most use of the RedCAT would be pointed upwards towards the sky.


Not sure if Astrotracer will be able to work with the 250mm focal length but initially I'll test it and see what happens.


Later on though once I am more experienced and understand a lot better I'll probably go for a lens that can grab planets and galaxies.


Yeah it's a shame that all these mounts are almost brand ordered from somewhere, a few of the ones that I've seen are $10k+. Though they're more for research and observatory purposes, unless you're absolutely loaded and have the space to fit a 100kg scope.


Just having read the manuals of different mounts, it looks like the Ioptron GEM28 is going to be the best solution for my needs down the line.

[MossyRocks]

There is a lot being asked here. As far as chasing DSOs there are a lot that can be had with fairly short (300mm and under) lenses. The RedCat 51 is as very good lens but if wanting to stay fairly wide another good option would be the Rokinon/Samyang 135mm F/2 UMC. That is a great lens that can be run wide open and there my only complaint is the vignetting which isn't too bad but I personally dislike. Beyond that I would look for some good used 300/4 lenses or even a 300/2.8, I have the Sigma 300mm f/4 APO Tele Macro and at f/5.6 is is a good astro lens that I got at a stole it price. It was my primary big glass until it got vastly outstripped when I got my A* 400/2.8 and there is just no comparison between the 2 as that 400 really is about is good as it comes for astro lenses.

I've looked into jumping up to a big equatorial and have asked around in the astro group and probably the best bang for the buck would be getting the Sky-Watcher EQ6R Pro and adding the MGEN-3 with a guide scope. However big equatorials like that are not what I would call terribly portable and I would view them as being car luggable as in drive to a location and then lug them a few hundred feet.

[AstroDave]

I'll probably go for the RedCAT lens as my next lens which can also double up as a terrestrial telephoto on the odd occasion that I need one - I prefer wide angle scapes in general so most use of the RedCAT would be pointed upwards towards the sky.

Not sure if Astrotracer will be able to work with the 250mm focal length but initially I'll test it and see what happens.

For similar prices, and perhaps a lot more flexibility, I'd suggest either of the Pentax DA* 200mm or DA* 300mm. Both of these work well on full-frame (i.e. K-1), despite nominally being APS-C lenses. And. both are highly rated in the camera reviews here for sharpness.

Astrotracer works fine with the DA* 300mm: First try of Astrotracer - Venus in the Pleiades - Not too bad! - PentaxForums.com

[kayasaman]

There is a lot being asked here. As far as chasing DSOs there are a lot that can be had with fairly short (300mm and under) lenses. The RedCat 51 is as very good lens but if wanting to stay fairly wide another good option would be the Rokinon/Samyang 135mm F/2 UMC. That is a great lens that can be run wide open and there my only complaint is the vignetting which isn't too bad but I personally dislike. Beyond that I would look for some good used 300/4 lenses or even a 300/2.8, I have the Sigma 300mm f/4 APO Tele Macro and at f/5.6 is is a good astro lens that I got at a stole it price. It was my primary big glass until it got vastly outstripped when I got my A* 400/2.8 and there is just no comparison between the 2 as that 400 really is about is good as it comes for astro lenses.

I've looked into jumping up to a big equatorial and have asked around in the astro group and probably the best bang for the buck would be getting the Sky-Watcher EQ6R Pro and adding the MGEN-3 with a guide scope. However big equatorials like that are not what I would call terribly portable and I would view them as being car luggable as in drive to a location and then lug them a few hundred feet.

Yeah the EQ6R is around 17kg / 37lbs. Definitely not something that would be able to be placed in an overhead bin of a plane, unless you want on your head after takeoff provided that it actually manages to get there unnoticed in the first place!

For a telephoto / longer reach lens I have been looking up and down the review section here but with so many choices it's easy for someone starting out to get lost.

The 135mm Samyang/Rokinon is on my list of "to-gets" in anycase as I absolutely love the 24mm f1.4. I think that Samyang is actually doing a really great job with their lenses though there are some people who claim that there is quite a bit of sample variation.


Ps. my newest images using the 24mm are these:

_IMG0662-5.jpg - Google Drive

_IMG0665-1.jpg - Google Drive

_IMG0666-2.jpg - Google Drive


where I have been experimenting with image mood. Though the last two nights I have been learning how to use bulb mode which was really cool

---------- Post added 08-04-21 at 10:10 AM ----------

For similar prices, and perhaps a lot more flexibility, I'd suggest either of the Pentax DA* 200mm or DA* 300mm. Both of these work well on full-frame (i.e. K-1), despite nominally being APS-C lenses. And. both are highly rated in the camera reviews here for sharpness.

Astrotracer works fine with the DA* 300mm: First try of Astrotracer - Venus in the Pleiades - Not too bad! - PentaxForums.com

Yeah, I thought about this already and read the reviews and looked at lots of pictures. They are great lenses and work well with the K1!

Actually the 200mm is around the same price as the RedCAT. I just thought that something more dedicated to the astro field might be a better option.

However, seeing your image of Venus is pretty nice! I have also seen people use the Pentax 100mm and Irix 150mm Macro lenses to get pretty good results when pointed up towards the night sky.

I have the Irix 150mm on my to-get list for macro lens so that could be a possible go-between for now (astro) option??


Difficult decisions to make!! That's what I really appreciate about this place is that there's someone who's been there and done that and can offer advice on their experience.

[AstroDave]

Actually the 200mm is around the same price as the RedCAT. I just thought that something more dedicated to the astro field might be a better option.

I don't see why. There's only so much diddling lens designers can do with glass, and this plus the Pentax (or any other good lens) have all pretty much reached the limits (minimal distortion, color-corrected, ...). And, either Pentax telephoto is intrinsically faster then the RedCAT.

And, here's Andromeda with my Pentax DA* 300: M31 - The Andromeda Galaxy - PentaxForums.com I've done a lot better since.

[kayasaman]

I don't see why. There's only so much diddling lens designers can do with glass, and this plus the Pentax (or any other good lens) have all pretty much reached the limits (minimal distortion, color-corrected, ...). And, either Pentax telephoto is intrinsically faster then the RedCAT.

And, here's Andromeda with my Pentax DA* 300: M31 - The Andromeda Galaxy - PentaxForums.com I've done a lot better since.

Wow!


Ok I'm sold


I guess I can grab the RedCAT later once and if I have spare change.


Though the game probably changes once you get into the more serious scopes.... for example: William Optics Zenithstar 73 APO Review | AstroBackyard

or this extremely large/powerful and expensive one: Photographing Orion with a William Optics Fluorostar 132

[VoiceOfReason]

Here's some of my stuff with the K1ii



And finally, something that was more of an experiment than anything and is ridiculously overprocessed,

I also have stuff on there from the K1 mk 1, K3, K5, and K-01 too for Pentax stuff.

As far as what you were looking at, get the mount with the highest capacity you can, so the EQ6R (though the iOptron GEM28 would be a good one if you wanted a light mount that is easier to handle) and the Redcat. I also have a Redcat and have gotten great images with it.

[Botanizer]

Andromeda Galaxy - Pentax K1ii with Pentax *300mm @ f4, ISO 800, 30 sec., using astrotracer for tracking. I took 47 lights, culled 25, and stacked 22 with DeepSkyStacker, with 8 darks, 8 flats, and 8 bias. Processed with StarTools and tweaked with Photoshop Elements 21.

[VoiceOfReason]

Ohh, and of you think photography is expensive, wait until you go down the rabbit hole of astrophotography. Here's my equipment list:

Cameras: Pentax K1ii, K1, K3, K5 astro mod, K-01 full spectrum, Samsung Mini, ZWO ASI178MC, ZWO ASI290MC, ZWO ASI533MC, QHY 5III 178 mono, QHY 5III462C, Astrel AST183-X-M-FW-7F, QHYCCD 294 M-Pro with Antlia SHO 3nm 36mm Pro, and Antlia LRGB 36mm Pro.

Scopes: TMB 92SS, Meade LX850 12", Orion ST 120, Celestron CR 150-HD, ES David Levy Comet Hunter, Lunt LS50THa, Meade SN10, Tak Epsilon 160, SharpStar 15028HNT, WO Redcat, Daystar 80mm, Skywatcher MN190, Orion 10RC, Borg 55FL, ES 127CF FCD100, RASA 11, Meade LX200 10".

Mounts: Modded go-to CG5, iOptron CEM25EC, CEM25P, CEM40, IEQ45, GEM45, CEM60 Pro with tri-pier, CEM70G with tri-pier, 2x Meade LX850 with Starlock, Orion HDX 110. 4x MGEN II autoguiders.

Feel free to check out my Astrobin here: https://www.astrobin.com/users/ImNewHere/

And

[cdd29]

Ohh, and of you think photography is expensive, wait until you go down the rabbit hole of astrophotography. Here's my equipment list:

Cameras: Pentax K1ii, K1, K3, K5 astro mod, K-01 full spectrum, Samsung Mini, ZWO ASI178MC, ZWO ASI290MC, ZWO ASI533MC, QHY 5III 178 mono, QHY 5III462C, Astrel AST183-X-M-FW-7F, QHYCCD 294 M-Pro with Antlia SHO 3nm 36mm Pro, and Antlia LRGB 36mm Pro.
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And

You forgot the Polaroid...

[VoiceOfReason]

You forgot the Polaroid...

lol, I don't think those would do too well for astro and probably couldn't be hooked up to a telescope

[cdd29]

lol, I don't think those would do too well for astro and probably couldn't be hooked up to a telescope

oh, but they can...

[damianc]

This is important as I only use Linux on my laptop

Indilib allows you to control shutter via USB thus obviating the need for a cable release/intervalometer. For my setup I have a rugged Intel NUC running Indiserver attached to the telescope, mount and guidescope and connect remotely from my desktop indoors where it's warm (important in winter!).
I guess you already read recommendations to prioritise the mount. I can't say I have a vast range of experience, but it looks like the soundest of advice.
The K1 being full frame gives telescopes a wider field of view than APSc, and I'm finding my Askar FRA400 to be quite a useful focal length