Lee_P

I cover mine with a Cygnus Astro cover. More details and photos here.

I thought that Askar were the first to try this but I've just seen that IDAS have already released an OIII+SII dualband filter -- the NB3, although I gather it's been discontinued. I wonder why...

I think for me the interesting thing about the filter is that it moves away from what I consider to be the benefits of OSC -- namely simplicity of data acquisition, and avoiding having to buy lots of filters. But if the end results are good that it could be an appealing halfway-house between OSC and Mono in those regards. I'm really curious to see how well it works under real-life conditions.

Here's something interesting: Askar are releasing a new type of dualband filter. It's OIII+SII, designed to be used in conjunction with the regular H-a+OIII. Askar are sending me one, so I'll give it a good test and will report back in the Members' Reviews section.

Sure, I've done this using SharpCap. It came out as something crazy-low like 10 seconds... just shows how bad my light pollution is! But just imagine an integration time of 20 hours composed of 10-second subframes 🥴

Oh yes, I actually screenshotted my WBPP Execution Monitor report, but forgot to include it on my site. Thanks for the reminder! My computer is an i5-8400 2.80GHz with 48GB of RAM, and all my astro processing runs off an NVMe drive. So fairly beefy, but WBPP still takes an age. Good question. I experimented with different exposure times a few years back when I first got a bunch of new kit; specifically, my ASI2600MC-PRO camera and Askar FRA400 telescope, along with an Orion Sirius EQ-G mount. I found that subexposure length didn't really matter; it was all about total integration time. I settled on 120-seconds as a sweet-spot for not being too taxing on my mount, making the most of gaps in clouds, and not resulting in so many subs that it filled my PC's harddrive / melted it during processing. Sticking with one subexposure length regardless of filter or target also kept things simple. The results have always been fine (gallery here). Having said that, I'm now using a new telescope and mount, so perhaps it's time I reran the experiment just to be sure. If my mount can reliably handle longer subexposures then I could be tempted to go to perhaps 180-seconds as standard, just to keep the total number of subs down.

It's great, and really quite something to behold in person! I'm writing a full review of it, just need a few more clear nights to produce a broadband image. Keep an eye out in the Members' Review section of the forum 😁

I've tested some light pollution filters from my Bortle 8 city centre, but found that they didn't actually help. So now I shoot broadband targets without one. More info here.

For the past few weeks I've been busy testing two new dualband filters, the Optolong L-Ultimate and Askar Colour Magic 6nm, to see how they compare with the classic Optolong L-eXtreme in real-world conditions. The review is now ready here: https://urbanastrophotography.com/index.php/2022/10/22/dualband-filter-shootout-l-extreme-vs-l-ultimate-vs-colour-magic-6nm/

The Elephant's Trunk Nebula from a city centre using an OSC camera. Lots more info here. * October 2022 * Bristol, UK (Bortle 8 ) * Telescope: Askar 130PHQ Flatfield Astrograph * Camera: ZWO ASI 2600MC-PRO * Filter: Optolong L-Ultimate and Askar Colour Magic 6nm * Mount: Sky-Watcher EQ6-R PRO * Guide: William Optics 50mm Guidescope with 1.25″ RotoLock; ZWO ASI 120MM Mini * Control: ASIAIR Plus * Software: PixInsight, Lightroom * 330 x 120 seconds (Optolong L-Ultimate) plus 330 x 120 seconds (Askar Colour Magic 6nm) Total integration time: 22 hours By Lee Pullen

Ah, good question! I've written about exactly that here: https://urbanastrophotography.com/index.php/2021/06/14/how-to-get-long-integration-times/

The first image using my new Askar 130PHQ telescope! Data was taken using Optolong L-Ultimate and Askar Colour Magic 6nm dualband filters. Imaging details below, and lots more info on my website. * October 2022 * Bristol, UK (Bortle 8 ) * Telescope: Askar 130PHQ Flatfield Astrograph * Camera: ZWO ASI 2600MC-PRO * Filter: Optolong L-Ultimate and Askar Colour Magic 6nm * Mount: Sky-Watcher EQ6-R PRO * Guide: William Optics 50mm Guidescope with 1.25″ RotoLock; ZWO ASI 120MM Mini * Control: ASIAIR Plus * Software: PixInsight, Lightroom, * 330 x 120 seconds (Optolong L-Ultimate) plus 330 x 120 seconds (Askar Colour Magic 6nm) Total integration time: 22 hours By Lee Pullen

Try as I might I just can't reproduce that colour palette! So no tiny stars for this picture, but I'll keep them in mind for future imaging projects 👍

This is an unusual one! An app for stacking has recently been released for Android smartphones. Is it any good? I've written a review here: https://urbanastrophotography.com/index.php/2022/10/22/review-eagle-image-stacker/ (The short answer for anyone that doesn't want to click through: it's got potential but needs more development).

Thanks @vlaiv, here's Option 2, binx2 -- whaddya reckon?

@vlaiv Thanks, yes, I see that now in those comparisons. Is there any benefit to binning an image at the end of processing, or has the ship sailed by that point?

Option 4: @vlaiv I binned this integrated stack before processing with editing. Not sure I did it right though as I can't honestly say I noticed a lessening in noise / boost in SNR.

Help me SGL, I've been editing this image for so long that I can no longer see the wood for the trees. Which version do you prefer? Option 1: Option 2: Option 3:

I'm currently writing a review that directly compares the L-eXtreme with the L-Ultimate and the Askar Colour Magic 6nm. It should be ready in a week or so.

I've been testing this filter extensively. In practical use there are no halos; but if you really stress test it with a bright star (e.g. Vega) then you will see halos.

In action right now!

The metal of the stock EAF bracket is quite soft. It's possible to use a small file to widen the gaps, perhaps enough to line up with the focuser screw holes. You may need to use a washer to ensure the screws are then tight against the metal bracket's widened gaps, but that's no biggy.

Mind you, if you're thinking that 1000mm is too long, you might be better off with the 107PHQ. I doubt that would fit an ASIAIR in the same way, but can't say for sure.

If you have an ASIAIR Plus then it'll fit beneath the OTA -- but only just. An ASIAIR PRO wouldn't fit. You could attach items to the handle, but I wouldn't recommend it if you plan on actually using the handle! Yes, the tube rings are threaded, so you could use those as attachment points. FWIW I've found the guidescope attached to the finder bracket to be stable enough.

Yep, I'm an imager. I don't have the reducer. (Note that if using the reducer, you need to achieve the specific backfocus). There's a standard bracket for a guidescope near the back.