tooth_dr

I was sent a screenshot of an email:

Apologies for not getting back to you. I concur that these are my settings too, however I still dont fully trust it yet! Never had these reservations with my EQ6

Happy Christmas Richard. A very nice sharp image indeed. I’d go as far to say it’s the best M45 I’ve ever seen. Something very delicate about it. Good to see you got some clear skies. The forecast didn’t hold last night and I only managed 45 minutes on M45!

My first triplet refractor, replacing a very reliable doublet. 94mm F5.5 with optional 0.8x reducer giving F4.4 @ 413mm.

Well guess what it came yesterday! The weather was clear very briefly last night between heavy heavy showers so I did get a test shot too

Haloes apparently. New one minimises them?

This is of interest to me as I have one on back order. Apparently they are accepting back the current batch of filters and exchanging for new improved versions. There was a statement from Ted Ishikawa. Anyone heard anything?

Thanks 👍🏼 Scope from FLO, but they dont list the reducer so suggested purchasing elsewhere. It was dispatched yesterday from 365 so will be tight if it arrives before Xmas.

There will always be those astro produces that are expensive, just as there will be cheaper ones. This has always been the case - a few years ago it was the price of large CCD sensors (before that it was the cost of refractors) - most of us bought DSLRs to get the large sensor at a fraction of the price and accepted the compromises. Your choice for not entering the hobby cant be based on the price of Chroma filters surely, when there are many many avenues to get started today, as @david_taurus83 says QHY/ZWO has revolutionised access to astro cameras.

Thanks Nicolàs, this is all very clear and I understand what you are saying. 30 step size currently gives me somewhere between a curve and V shape - much like my post above. I'll try 11 data points later along with a slightly smaller step size. I dont mind if it takes 5 minutes longer, as at F2.8 it is very finickity, so a few minutes getting exact focus is not an issue. I appreciate the help. Adam

Thanks, I have my backlash set to 50 and 'IN'. I may increase it though as I dont think having too much matters. I'm not sure it is a backlash issue though

It's forecasting clear skies tonight unbelievably - so my plan is to reduce the exposure time and try this again. Using SGP - i went through the instructions (in focus then move to 4 x HFR) - the calculations give a 30 step size. Will I just stick with this? If I make it 11 points, does that mean the total excursion is the same, but points of the graph are just closer together? This has got to be a benefit? Thanks in advance Adam.

The focuser is just back from Moonlite following an upgrade and I would have no reason to suspect any issues. In fact the whole thing, stepper motor and all, was setup by Ron, I just unpacked it and fitted it to the tube! I’m well below the weight limit that it has been set at so I don’t suspect slippage, but I can do a check tomorrow. It does give a good v curve though, I regret not taking a photo of the screen last night. It just seems to lack precision when selecting the best fit points, and ultimately the exact focus position. Perhaps my exposures are too long. I really need a clear spell to check these suggestions.

Very nice Richard, a real beauty and a piece of art.

I agree, and I was off work. Finally 2020 has come good 😋

This is my first light with my new SharpStar 94EDPH scope. Unbelieveably it was clear on the night of receiving a new piece of astro kit Camera: 290MM, 1000 frames with 50% stacked Scope: SS94, prime focus 517mm F5.5, stacked in AS!3 and processed in Registax and PS. Thanks for looking Adam.

It’s a bit like Sii, but I’d go as far to say that looks like luminance.. This is my Sii: and my Ha

Thanks Dave. I did have an issue in the beginning with my Hitec Astro Mount Hub Pro and Moonlite. The CFZ of the Epsilon is 17um, and the focuser originally went in steps of 10um. I sent the MHP back to HA and they updated the firmware to accommodate 2um steps. I will try shortening the exposure time and increasing the steps. I've noticed that sometimes it selects two stars as one star - if there are a couple of stars close together it puts a circle around both of these.

Ok, thanks. I'm using 2x2 binning, 8 seconds on luminance and 15 narrowband. Perhaps this is too long for the scope 180mm/F2.8

Very interesting! Would you have any input into the value to use for min star detection? I wonder why it's not going to the point of best focus?

Hi Starflyer - thanks for the reply. 30 steps gets me an increased HFR of x 4. I've been using that, but changed it last night to see if it worked any differently - actually to see if the sharp curved helped! Hi blinky - I actually have a second autofocusing unit running simulataneously on another scope, using the DeepskyDad AF3 system. It is operating a much slower F ratio but appears to be accurate. I set them both up the same way. The problem with the focusing has been there for a few months so I think conditions arent a contributing factor. I dont have an example of the focusing from last night, but have attached one from a few weeks ago on the other scope below. Just to reiterate this isnt the focuser/scope that is causing me the bother. Thanks Nicolas - I note that you are using 7 points and the difference between the in focus HFR and the end points is only 0.5. What setting are you using?

That’s a fabulous image Stuart. One of the best I’ve seen on this. Well Done on the Tip Pick.

Any tips of fine tuning it? I have followed the SGPro instructions and set up my autofocus routine according to that. I've ran the focusing routine a few times tonight, and it never seems to find what I would visually determine as the best point. Just now the computer settled on position 2415 based on the V-curve, however I could clearly see my diffraction spikes werent merged. I subsequently ended up moving it to 2422 and the spikes merged. My settings are 30 steps and 9 points, have tried upping it to 42 also (this gives me a 4-6x HFR increase over focus). When I watch the best fit curve, it doesnt always seem to be the best fit if that makes sense, in that the lowest point according to SGPro isnt what I would say should be the lowest point. I use 8s exposures, 2x2 binning. Any help very gratefully welcomed.

I received my SharpStar 94 today, a replacement for the ED80. It’s very similar focal length, 517mm, F5.5. It’s clear tonight so hopefully can start a thread on it later. The 0.8x reducer should have been here but alas it wasn’t in stock (despite being listed as several in stock) so fingers crossed it arrives before Xmas

I do something similar, except I hang it upside down by the dovetail and balance it across my index fingers 🤪