Experience and recordings with ACUTER Elite Phoenix 40 H-alpha solar telescope

Hello Karl,

The Acuter arrived safely, of course. I did the first tests today in beautiful sunshine:

Comparison
- Lunt LS50 with B600
- Coronado PST with BF10
- Acuter Elite with its 8mm BF

... what can I say, I have no idea how they managed it technically - but:
- the Acuter is worlds superior to the other two; the bandwidth is roughly equivalent to a PST double stack, which I also had.
- there is no visible sweet spot like with the PST or LS50. Only when you move the sun disk to the edge of the field of view does the halo pass visibly flatten.
- the illumination is absolutely flat, also no comparison to the other two. We'll see if it even needs flats for photographic use.
- there are no brightenings around the sun disk (like with the PST), there are no reflections, or Ghost images
- For full-disk photography, this thing is a dream; even with the current sun position and a Hyperion zoom at 24mm, the solar disk is still sufficiently bright - this gets even better at higher sun positions, of course.
- The included accessories can be put in a drawer and forgotten. The zoom eyepiece isn't that great, but at least it's a good starter, the phone holder - well, if you need it :)
- The Acuter Etalon appears to have an ERF or red filter installed.
- An unnamed UV/IR cut filter (KG3?) is screwed in front of the Acuter BF.

For fun, I tested a few more combinations.
- Acuter Etalon + Lunt B600: unusable, image is much too dark.
- Acuter Etalon + BF10: slightly better, but also quite dark.
- Lunt LS50 with BF10 delivers a better, brighter image. Image taken as a Lunt LS50 with B600
- Acute standard on the LS50 - the front standard, so to speak, as a double-stack standard in front of the LS50: very high contrast, unfortunately very dark, reflections between the standard and the front lens of the LS50... that was actually the combination I wanted to use - but because of the reflections, I think it makes little sense.

Summary:
- Absolutely thrilled, from a technical perspective, there are a few question marks here and there (air-spaced standard and 0.6A? How?
- In terms of price/performance, neither Lunt nor Coronado can compete (in this price range, mind you).

If the weather cooperates, I'll do some photographic comparisons with the PST and LS50 and the Acuter in the next few days...
...

And here are the first pictures

- Acuter Phoenix Elite 40
- ZWO ASI 178mm
- Skywatcher SolarScout
- 25% of 2000 frames each

Pretty great - I think, considering the current position of the sun...

Jonas

Link to the ACUTER Elite Phoenix 40 40MM F/10 H-alpha Solar telescope:

https://www.teleskop-spezialisten.de/shop/Sonnenbeobachtung/H-Alpha/Komplette-Teleskope-fuer-H-Alpha/ACUTER-Elite-Phoenix-40-40MM-F-10-H-alpha-Sonnenteleskop::7135.html