Astrophotography Japan / MK105 Planetary Imaging (Episode 26)

[@txdave2]

I have been considering purchasing this scope. I am new to astronomy and feel this scope offers a tremendous value. I enjoyed your video and images.

[@jpastroguy]

Thank you. I am glad to hear you found the video enjoyable. The MK105 is an excellent value for viewing double stars, globular clusters, planets and the moon. But of course, it is too high power for viewing many asterisms or other commonly viewed star clusters (Pleiades, Hyades, etc.). Thanks for watching. Clear skies!.

[@adventuresofshadowdog]

Another excellent video! Thanks Paul!

[@jpastroguy]

Thanks (again), and best wishes in 2024! Give my regards to "Shadow", too!

[@Paul-ds9fh]

Hi Paul, Thanks for another inspiring video and your detailed explanation. Impressive results.

[@jpastroguy]

Thanks Paul. I gathered some new planetary data today and am planning a follow-up soon! Clear skies!

[@sekitv]

Thank you for very nice and interesting story Paul san!! I love your video every episode !!

[@jpastroguy]

I am happy to hear that! Thanks!

[@matthiasharbers2533]

Happy new year! Your new video was a very enjoyable start for 2024. Looking forward to seeing more of your videos as the year progresses.

[@jpastroguy]

I have gone a bit crazy lately.....several videos completed just during the Winter break. But I have many other ideas! Happy New Year!

[@matthiasharbers2533]

Looking forward to your next videos!@@jpastroguy

[@jpastroguy]

Gimme a break!

[@captaincook6666]

Great images. I also have a flip mirror for this. I only have a C90 but still can see the ring changes on saturn over last 3 years.

[@jpastroguy]

Hey Captain, nice to hear from you. It’s sad that we are going to miss those beautiful rings for a while. Thanks for watching again!

[@AmatureAstronomer]

Very nice.

[@jpastroguy]

Thank you. All for fun!

[@davido2644]

Great video! Just a detail: setting the camera to a smaller ROI doesn't change the resolution. Each pixel is still covering the same area in the sky, and it's only that your total covered area is smaller. For higher resolution you need to increase sampling, typically by using a barlow or focal extender (within certain limits given by the scope and the atmospheric seeing), and/or using a camera with a smaller pixel size. The most common rule of thumb calls for using a focal ratio equal to (in practice, close to) 5 times your pixel size in microns. A 3.75 micron pixel size would require an f-ratio close to 18.75. So on an f/6 scope, a 3x barlow will give you close to optimal sampling, if seeing allows), while on an f/10 a 2x one will do. Others use a 7x criterion for excellent conditions, which seem to work better with Mars and Venus.

[@jpastroguy]

Thanks David for the mathematical details of the optimal OTA/ camera spec relationship. I think that my video was generally consistent with your explanation, but without the specification explanations. I have to admit, the concept of "sampling" is not so intuitive to me; mainly "over-sampling". I just don`t quite fathom why there should be a concern in "that" direction. Thank you for watching and sharing your knowledge. Clear skies! PAUL

[@jpastroguy]

David, I just realized that it was the follow-up planetary imaging video (#27), that clarified some of the word choices (like “resolution “) that you mentioned in your comments. Have a look at that video if you have time. Unfortunately, the views are a bit less, so not all viewers got the clarification message. I appreciate more experienced viewers like yourself offering clarifying comments and helpful details! Best wishes!

[@HollomanUFOLanding]

Happy New Year! Congratulations on a very well put together video and great images of the solar system objects. I employed a similar technique to get planets into the field of view of my camera, using a flip mirrow. Aligning eyepiece to the camera during the day helps a lot. For those not familiar, first of all simply focus the camera on a distant terrestrial object. Once the camera is focused, adjust the eyepiece in the flip mirrow. The goal here is to have the eyepiece and camera focused such that they match each other IE when the flip mirror is changed between the tow, the image is in focus in each. In focusing the eyepiece, it may be necessary to use a helical focuser and / or extension rings (Svbony sells these) to help the eyepiece reach focus. The important thing though, is to always to focus the camera first, then the eyepiece. Otherwise one can get in an annoying focusing loop! Instead of a laser finder, I use a Telrda mounted on top of the OTA. Align the Telrda with the OTA during the day - this is a crucial step. Then, once dusk or darkness comes, the OTA can be slewed towrard the planet and then centered in the Telrad and, hopefully, you should see the planet in the field of view of the eyepiece - after having adjusted the focus from tererrstrial focus to space focus. Having a mount hwere sidreal racking can be enabled helps a lot here, or use a simple 1 or 2 star alignmnet to get tracking started. I prefer the Telrad to a laser as it's a little more 'organic' for me and very simple to install. You can leave the Telrad base installed on top of the OTA and then use it on other OTAs if you wish.

[@jpastroguy]

Excellent Points - all of them - it's exactly how I do it, too - Your description is more tutorial-like and provides excellent supplemental content. You have described a more deep step-by-step outline of the process. My video focus was a bit more idea and story-telling entertainment than instructional; I guess it is just my style. Thanks for the rich comments and for watching Astrophotography Japan!

[@lpaelke]

I have a similar telescope (Skywatcher Skymax 102 Mak) and use it with the ZWO ASI678MC camera for planetary imaging. Like you, I also had problems with the small field of view when using an ASIAIR. My solution was to adjust my guide scope really well so that it points at exactly the same point as the main scope. Then I set the guide camera (a ZWO ASI120MM mini on a 50mm f/3.5 finder scope) as the main camera in the ASIAIR. With its much wider field of view, plate solving works much better. So when the planet is centered in the guide scope, I switch the setting to the 678 on the Mak as the main camera and start imaging. Cheers, Lutz

[@jpastroguy]

Hey Lutz, thanks for the comments. Your automation approach using a guidescope and guide camera to do the target centering sounds great! Thanks for the tip! I think I tried that in video #6, but I still could issues - probably because it was not PERFECTLY aligned. Also, as I determined in that prior video (#6), there does not seem to be much difference between the 533MC Pro and the 678MC camera in terms of resolution for planetary imaging. However, I want to try again with the 678MC camera when I get a night of really really good seeing. Perhaps then it will provide an advantage (?).... Theoretically, it should.

[@psuaero100]

Great video. I'm curious if you tried sending the ASIAir to a temporary target near (1-2 deg) the Moon, Jupiter, or Saturn. Just a plain starfield and then allowing it to plate solve and know the mounts precise position. Then it's just a short slew to the primary target which should be very accurate. I did that with my Esprit100 (only 550mm) when imaging the Moon. I don't recall having any issues.

[@jpastroguy]

Good point. I have done that using Mount-based goto function for visual astronomy. It definitely works fine at low focal lengths. I just never thought of doing that with the ASIAIR. Duh! I will definitely give that a try next time! Thanks!

[@psuaero100]

@@jpastroguy Also, I'm curious why you said you took a higher resolution image at 640p rather than the larger 1080p. If you're just reducing the region of capture on the sensor you're speeding up the frame rate but the pixels are still the same size and the focal length/magnification is the same, right? I think zooming/cropping on the 1080p should result in the same magnification. I'll admit I'm a little rusty on my planetary as I've been without a long focal length scope for a while (something I'm hoping to rectify this year with a new SCT). I've been concentrating on DSOs for a few years.

[@jpastroguy]

Good questions. Please do not consider me an expert in planetary imaging. I have literally only done it 3-times. The points you make are sensible and logical and I have thought about it as well. However, it seems to me that somehow the video image processing algorithm reacts to them differently. If you take a 1080P video and a 640P video of exactly the same length and on the same night (identical conditions), and compare the processed images, there are subtle differences in the quality and resolution. I am not entirely sure if this is my imagination, but it led me to look for the optimal point which I usually see around 640P or a stop below that. I honestly do not know if this description and phenomenon is real or not (my imagination?). And if it is, it may also depend on the processing software, I would guess. If you want more than that explanation, you will have to find an expert.......and that is not me. I am a KZbin storyteller mostly (entertainment) but sometimes I enjoy doing experiments and sharing the data in a video format, as well. However, I try to be absolutely honest in my assessments and data and speculation. Thanks for you questions, comments and interest in Astrophotography Japan.

[@HelmutBemboka]

Hi - have you ever collimated your mk105? Mine is out and I was just wondering how this was done.

[@jpastroguy]

Hello Helmut. I have never needed to collimate my MK105. Sorry, but I cannot help you. But thank you for watching Astrophotography Japan! PAUL

[@HelmutBemboka]

@@jpastroguy ok thanks for getting back to me 🙂. Excellent videos!

[@jpastroguy]

@@HelmutBemboka Thanks Helmut. I really appreciate hearing that! Clear skies!

[@GeraldXD]

Hi! Can it be used with a focal length reducer to watch big things, for example Andromeda or Pleiades?

[@jpastroguy]

I do not think so. I tried a cheap focal length reducer lens that I bought off AliExpress. It worked, but it was like looking down a tunnel. I am not aware of any reducers designed for MAK telescopes that work. But I am not an optics expert; so you might want to ask that question on Cloudy Nights. Thanks for watching Astrophotography Japan! Clear skies! PAUL

[@jpastroguy]

BTW, my recommendation is to buy a refractor, like the new SV48P 102mm scope and boost the magnification with a good 3x Barlow lens. That works very well for sure.

[@GeraldXD]

@@jpastroguy oh i see, and yeah i saw that SV48P 102mm too it looks a good telescope, thank you for your advice man, good video btw.

[@jpastroguy]

@@GeraldXD Thanks. One more thing. I k know that focal reducers do exist for mirrored scopes (of course) but they are all designed for 2 inch barrels. The MK105 only has a 1.25 inch eyepiece barrel size.

[@GeraldXD]

@@jpastroguy oh ok, i'll keep it in mind 👌🏻

[@Rizqi_jo]

Apakah Anda mengambil video memakai kamera handphone ?

[@jpastroguy]

Saya biasa menggunakan ponsel untuk mengambil foto ketika pertama kali memulai astrofotografi sekitar 3 tahun yang lalu. Tetapi sekarang, saya secara eksklusif menggunakan kamera khusus astro dan mengambil semua foto dan video dengan kamera tersebut.