Celestial hemisphere:  Northern  ·  Constellation: Leo (Leo)  ·  Contains:  Leo Triplet  ·  M 65  ·  M 66  ·  NGC 3623  ·  NGC 3627  ·  NGC 3628
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The Leo Triplett (M65/M66/NGC3628) in LRGB with Televue 2x Powermate at 1850mm FL and f/14, Uwe Deutermann
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The Leo Triplett (M65/M66/NGC3628) in LRGB with Televue 2x Powermate at 1850mm FL and f/14

Revision title: 1x stars with 2x galaxies

Getting plate-solving status, please wait...
The Leo Triplett (M65/M66/NGC3628) in LRGB with Televue 2x Powermate at 1850mm FL and f/14, Uwe Deutermann
Powered byPixInsight

The Leo Triplett (M65/M66/NGC3628) in LRGB with Televue 2x Powermate at 1850mm FL and f/14

Revision title: 1x stars with 2x galaxies

Equipment

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Acquisition details

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Description

My first image solely taken with the new setup using the 2x Televue 2" Powermate to increase the focal length to 1850mm with my WO FLT132 (did I ever mention that I just love this scope? 😊). 
So this is my desperate trial (one of several to come) to overcome buying an 8" refractor (or even larger) to be able to "compete" with an SCT. Many people might say: why don't you get one? Well ... one day I certainly will, but for me there is nothing that can compare with a wonderful refractor, the images just look different, smoother in general, they have a touch that I love, cannot really explain it. Maybe because my main instrument that I did visual observations with during my university time was a huge refractor, nostalgic I am.
I chose multiple targets for the trials, this is my first one, the "easy" one since all 3 galaxies are fairly bright and have some nice structures that are so awesome when looking at galaxies far far away 😊.
Main obstacles/refinements/etc. were:
1. Flats: as already shown in the M42 image that I recently posted, the flats are enormously important when using the 2x, it seems that it just brings out the tiniest of dust particles that reside on your glasses. And no, my environment is not a dirty one, flats taken at 1x do not show those at all. So every night after my sessions I took flats, and they definitely helped me a lot when stacking the images together.
2. Settings in SGP (and certainly in all other auto capture programs as well): Beside the normal adjustments to the new FL and pixel size, it was very important to adjust the autofocus. The step size needed to be lowered since just a 1000 steps in or out resulted in images that the star detection mechanism could not deal with anymore. Also, increase the exposure time for plate solving and autofocus, at f/14 everything is much less intense.
3. Plate Solving: even with the prolonged exposure time, it was for some targets (I targeted 8 in total so far) not possible. Luckily, my mount is adjusted well enough to point to the correct destination within a few hundred pixels by itself.
4. Integration time: Yes, you need much more than what you would need with an SCT, but I take it, especially since the weather was just phenomenal the last month, many clear nights for us here in Florida.

All in all, I am quite impressed on how this trio turned out (compare with my "old" image from March 2020 in Version B)! I know it is not a special target, I believe almost everybody on Astrobin has it on her/his catalog, but I wanted to get as best as possible details out of the galaxies, which I think was successful. The stars are not as nice as they could be, mainly because this trio spanned across the whole frame, and at the edges the back focus adjustments are super sensitive with the 2x. Smaller targets are in the making, where this does not play such a role anymore.

A sneak peek on my next targets show that there is a limit at f/14, but this is "reserved" for the projects that will be presented in the following weeks. I collected quite some data in the last weeks, cannot process them fast enough, which is good since Summer will be upon us soon (actually, the next 4 days show already thunderstorms after thunderstorms), and then I will share the suffering that a lot of you had in the last 2–3 months, no clear skies.

In my next clear nights I will try to get the same area at 1x and see if I can use at least the stars from those images and integrate them in this one, this might be possible, and it would probably enhance the overall image quality. It will be also interesting to see the difference in resolution inside the galaxies, is it really better at 2x?

Let me know if you have any questions about the setup (Version C) if you also want to dare to take the route of very high f ratios from your light polluted backyard.
* This image was not submitted for IOTD consideration

Comments

Revisions

  • The Leo Triplett (M65/M66/NGC3628) in LRGB with Televue 2x Powermate at 1850mm FL and f/14, Uwe Deutermann
    Original
  • The Leo Triplett (M65/M66/NGC3628) in LRGB with Televue 2x Powermate at 1850mm FL and f/14, Uwe Deutermann
    B
  • The Leo Triplett (M65/M66/NGC3628) in LRGB with Televue 2x Powermate at 1850mm FL and f/14, Uwe Deutermann
    C
  • The Leo Triplett (M65/M66/NGC3628) in LRGB with Televue 2x Powermate at 1850mm FL and f/14, Uwe Deutermann
    D
  • Final
    The Leo Triplett (M65/M66/NGC3628) in LRGB with Televue 2x Powermate at 1850mm FL and f/14, Uwe Deutermann
    E

B

Title: Comparison of the same area: 2020 vs. 2022

Description: I took the 2020 image with the ASI1600 and the Explore Scientific with FL 714mm, also less integration time. So this is a bit comparing apples with bananas, still ... they must compete since they are both mine 😊.

Uploaded: ...

C

Title: How I used the Televue 2x Powermate in my imaging train

Description: Actually, I added one more spacer of 3 mm since this was still not enough. I believe I could use even a tick more after processing more images, but well, it is quite close to the perfect distance.

Uploaded: ...

D

Title: 1850 mm vs 925 mm FL comparison.

Description: Needed to do the comparison since I was curious what the main difference between a 1x and the 2x Powermate setup is.

Differences:
app 5h with the 2x Powermate (L subs) at bin 2x2, app 2h with the flattener alone at bin 1x1

Identical:
1. Everything else, from the filter to flattener to scope to camera.
2. Processing: Absolute identical steps from the stacked image, same noise reduction routines (to the point), stretching, etc. I processed both images in parallel to guarantee that there will be no changes.

Result: as expected, the stars look much nicer in the 1x1 at 925mm, but I am impressed although not understanding at all that the signal for the 2x looks stronger, I am puzzled. A close look at details shows that the 2x does not seem to be better. Interesting though was that I could not get the same nice image together using the L from the 1x setup and using the RGB data from the 2x, it just did not come out right.

Conclusion: not sure if I continue using the 2x on DSOs. It certainly was worth the try, and in some ways it looks like that it was better to process, but I do not have enough experience with it, hence I still have to wait for more examples. The next image was not that bad either, so definitely not a failed try. Was way more work (at least it seemed like it) involved. With the new filter wheel that might get a bit easier then. I definitely will give the 2x a go for the moon and the planets, this will be interesting!

Uploaded: ...

E

Title: 1x stars with 2x galaxies

Description: Of course I could not resist to use the stars from the 1x L data and integrate them into the 2x version. I extracted the 1x stars and the 2x stars and applied only the color of the 2x stars (from the previous final image) to the 1x stars so that L suddenly became LRGB 😊. Then integrated them back into a starless version.

Uploaded: ...

Sky plot

Sky plot

Histogram

The Leo Triplett (M65/M66/NGC3628) in LRGB with Televue 2x Powermate at 1850mm FL and f/14, Uwe Deutermann