thomasv

Would have thought it depended on the reflectivity of the blind. If the blind is ideal black, i.e. was absorbing all of the light that falls on it, and assuming no light is reflected back from the windows after opening the blind, then it should appear the same?

However, if the curtain was made of aluminum foil, it would make a difference opening the blind?

Thanks StargazerUK, I was looking under the 'Camera' tab only and missed the focus setting under the 'Night Sight' tab.

Brilliant, I shall try to repeat my with filter experiment, was going to try a dual band filter too, maybe when the milky way is visible again.

I have the Pixel 7 pro and had a few experiments just on its own, no scope, mounted on a tracking mount. Below is a single AP shot from Bortle 5 zone. Not great, just wanted to see if it picked up the comet that was not visible by eye. 

I was then hoping to use it with a 2" light pollution filter blue-tacked over the lenses, but that did not work, as it messed up the focusing, with light from the time of flight sensor reflecting back I think also. I could not find a way around this, not sure, why they don't just fix the focus at infinity once it goes into AP mode. There is no way to override the auto focus. AP mode is good, but the lack of manual mode do annoy me a bit.

This looks very impressive, thank you for publishing.

Wonder if it would make sense and be possible to add a feature that allows the stacking of light frames captured 'offline', as opposed to live stacking. Suspect that wouldn't be too difficult, as all the underlining algorithms are already there. Given the recent improvements in camera phone performance,  that would make it possible to use a smartphone for both capture and stacking, which may be fun to play with.

Regards.

Interesting.

" this filter is not suitable for fast ratio systems ". Wonder if it's possible to quantify this a bit more precisely, what f number should be the limit? I know it's not a hard limit, but what would be still acceptable, is there any guideline?

Thanks.

On 30/05/2022 at 08:29, icpn said:

i think you are getting confused with the La Palma observatories on a different island. The Teide observatories are on Tenereife and are mostly small telescopes devoted to the Sun..

Absolutely, sorry, I did get confused. I did do the tour around Tenerife observatories too, but you are right, probably less interesting than on La Palma. Still great skies, of course, we drove up one night, and enjoyed the sight, that is until a group turned up with their laser pointers. 😬

There are organized guided tours that you can book in advance, which also let you have a peek inside GTC. I do recommend it, let me know if you can't find the link. 

The highest point is on a different peak, 4000+ meters, you can take the cable car to near the peak, but if you then want to walk to the peak you will need to book a permit for the day, as there is a limit on the visitors per day. And don't forget that despite it being Tenerife, at 4000m in December it will get pretty cold, so even if you book in advance, some days the access to the peak or even taking the cable car may not be possible. 

Looks great! Is it cropped or does it come out 'that big' with 135mm focal length?

May I ask if you've stopped down the Samyang, just wondering if potentially there are color gradient issues with fast optics and these dual band filters?

Thank you.

Thanks Vlaiv. 

Do people have an opinion whether my camera has too many defective pixels? This is a 1min dark, ISO800, screenshot of the raw file, showing about 1/4 of the frame. Taken at room temperature, no stretching applied.

Hi, does using bias frames only deal with defective / hot pixels?

My camera has a few of these, especially when exposing for several minutes. I've tried using a defective pixel map in Astroart, but it doesn't fix them perfectly, still get some faint trails without dithering. Dithering does help, but it's a bit annoying as I'd like to use my 6D with portable mounts without dithering.

3 hours ago, gorann said:

Hi Thomas,

I could not find anyone selling such an adapter so I made one by taking apart an EOS-FD adapter from ebay (image below) and attaching it to this adapter from FLO:

https://www.firstlightoptics.com/adapters/astro-essentials-samyang-lens-to-m48-adapter.html

Had to drill three holes and put it together with three M1.6 screws and nuts.

Cheers, Göran

Thank you very much for the reply, I shall attempt the same. Regards.

Hi Gorann,

Cool setup, good luck. A side question, how did you connect the FD lens to the ZWO camera, do you know where to get the adapter from?

Thank you.

Do you mean the larger ones, or their portable trackers?

I have a Lightrack II and I'm very happy with it. I've posted some performance data and pictures with it on this forum, let me know if you can't find them.

t 

Yes, it consists of two lenses held at a distance by a spacer ring. Sorry my first picture is not very sharp, the middle bit between the lenses is the spacer ring. I've moved all three parts over to the extension tube, so hopefully will be OK. 

The SW field flattener for Evoguide 50ED is not suitable for DSLR or mirrorless cameras, as it's backfocus is 17.5mm. My mirrorless camera (Fuji X-T1) has a flange to sensor distance of 17.7mm and the T2 to camera adapter ring that I have on order is 8.3mm thick, so the original flattener tube is too long by 8.5mm. I've noticed however that the extension tube that comes with the evoguide is approx. the correct length. Unfortunately, the internal diameter of the extension tube is slightly (by about 0.3mm) smaller than the diameter of the lenses, nothing that cannot be solved by a couple of hours of sanding.

Next step will be to 3D print a couple of rings that hold the lens assembly from each side. Conveniently these rings can be fixed in place by the two sets of  3 grub screws, one set in the extension tube another in the scope itself, allowing for an easy way of adjusting the exact position of the lenses.  

Showing the length difference between the flattener and the extension tube below, and the lenses now inside the extension tube. Will report back on progress and performance, unfortunately the T2 to fuji adapter is going to be 2 weeks wait.

Hi, great picture. Just a question as you have obviously captured well the Ha wavelength, do you have the EOS R or EOS Ra ?

Thanks.

Hi, great photo. Just wondering why you convert first to tiff, AA7 does handle RAF files. Interested in any benefit as I also have XT1 and AA7, but always just work with RAF out of the camera. 

Thank you for the reply. I wonder if I should get Astro Pixel Processor, I hear from more and more people who use it, might as well try the free 30 day license. I have AstroArt, maybe I'm just not good enough at using it.

Beautiful. Wonder how dark your sky is and are you using any LP filters? Do cal with darks / flats, etc? Thanks.

Wow, how lucky is that? Are you going to stack the comet subs and combine it with the meteor picture? I wouldn't even know where to start ...

I would say a planetary camera would probably give you far too small field of view. The tail is at least 6deg long.

I think DSS now supports fuji raw, worked for me.

"The list of the DSLRs supported by the latest version is available on the libraw web site."

Another sleep-deprived night in a muddy field, glad these comets don't come around too often 🤪

Fuji X-T1, Samyang 35mm f1.2 @ f2 & vintage Asahi SMC 50mm f1.7 @ f2.8.

Re-process.

Almost didn't get up when the alarm went at 1:50, but glad I did, first clear morning to see the comet, plus bonus noctilucent clouds.

Fuji X-T1 / Samyang 135mm @ f2.8, 20 x 9sec iso400.