Merlin66

I'm revisiting this topic..... I found that most (All?) CMOS sensors are fitted with microlenses and the immediate chip cover plate can vary in thickness from 1 mm to 5 mm (!!!!) If this was a real problem then surely it would be showing up on more and more images taken with CMOS cameras? It seems strange the the prime example here and CN is of one star - Anitak I've never experienced this type of issue.... we do suffer more from "ripples" in our spectrographic profiles - an intensity waviness - thought to be due to either/ both the internal structure of the silicon chip or interference between the cover plate and the silicon surface. See: https://www.lensrentals.com/blog/2014/06/the-glass-in-the-path-sensor-stacks-and-adapted-lenses/ http://www.astrosurf.com/buil/CMOSvsCCD/index.html https://britastro.org/sites/default/files/attachments/SpectralResponse_WhitePaper_April09.pdf ( thanks to Robin for the link) Is there a real problem here????? Interesting comments here about the KAF 3200ME with microlenses: http://www.wvi.com/~rberry/astronomy/qsitesting/kaf3200me.htm Quote: Micro-Lens Artifacts Micro lenses are tiny cylinder lenses designed to concentrate light on the indium tin oxide half of each pixel in the KAF 3200ME. Although I can imagine scattering from one micro lens to adjacent micro lenses could account for some artifacts, they may also be the astronomical equivalent of the “urban myth.” Because I aligned my camera precisely north-south and east-west, I was not able to attribute possible low-intensity extensions along rows and columns in my images with any certainty to spider diffraction or blooming. If the effect is real, it is very small.

Many of us successfully use EQMod to control our HEQ/NEQ SW mounts. Using a EQDir cable you can bypass the hand controller direct to the mount. You should have the latest ASCOM installed, then EQMod ...... Accessed through a planetarium program (I use Cartes du Ciel), EQMod gives you the opportunity to sync, and control the mount from a laptop etc.

Very nice result! Re AS3! (I use AS3! ) I've done some comparisons on my solar images using 10/50/75 % "best frames" and to be honest the 50% result was probably better than the top ten 10%. Worth trying yourself to see if it works for you. Ken

+1 from me for AstroArt - it does all my acquisition, guiding, preprocessing and post processing. check out the free download - punches well able it’s weight.

Re. Microlens artifacts with the ASI 1600, other than the example on CN I haven’t seen any issue with the multitude of images from this camera..... Maybe I’m missing something??? I use the ASI 1600 ( a replacement for the rejected ASI 183 ) for solar imaging, with no issues.

John, If they are marked "Japan" on the black body, you may be pleasantly surprised!

Back in the 60's I started out with Norton's Star Atlas.....helped me come to terms with astronomical terminology and finding my way around the sky. Now in it's twentieth edition. it has enhanced charts, each chart with a list of "Double Stars", Variable stars", "Clusters nebulae and galaxies" to observe. Highly recommended. https://www.abebooks.com/servlet/SearchResults?isbn=9780131451643&n=100121503&cm_sp=mbc-_-ISBN-_-used

Meade series 4000 "super plossls" - the early smooth sided, marked "Japan" on the black body were actually five element design "Masuyama clone?", the later versions marked "Japan" or "China" on the chrome barrel were four element similar? to the other Series 4000 eyepieces. Which one did you test?

I've been using the Borg equivalent non rotating helical focuser on Spectra-L200 instrument for almost ten years. They work, and work very well. (when connecting to the external T thread, the eyepiece screws need to be removed - and replaced by dabs of BluTak to limit light intrusion)

Well done, Nigella - good to get some recognition!

Bumma!

Kev, Sounds like the grub screws which hold the gears to the shaft may have come loose????? I'd double check that before panic sets in..............

Being a manufacturing/ production engineer for fifty years, I appreciate your frustrations..... BUT you're currently playing with, I think we agree, a scope from the bottom end of the market. There are thousands of amateurs using refractors/ reflectors which although not perfect are capable of performing to their needs. I do have one serious area of "complaint" - the "safety recess" found on eyepieces/ accessories was invented by the Devil - and should be banned. Ken

Onwards and upwards! A centre spotted paper target over the front of the objective - the laser spot should hit centre...... I also use a Cheshire collimating tool - illuminate the side and look at the reflection doughnuts at the objective. Ideally they should be uniform and concentric. That's as good as things need to be. Suiter's "Star testing Astronomical Telescopes", p122

I used to work in Muskoka, Ontario where it got down to -20 deg c in winter!!! I still have a small scar on my eyelid where the skin froze to the eyepiece!! (The grease also froze in my tracking mount....) Things are a bit easier here in Oz, but observing at +30 deg c at night (!!!) has it's issues.

Whooooo!!! That's scary!! I use a very similar power set-up with AstroZap dew heaters and controller (#AZ-720). Never experienced anything like that.

The ZWO website shows 6.5mm camera back focus....this means that the front of the camera should be that distance in front of the prime focus. https://astronomy-imaging-camera.com/product/asi183mc-pro-color An image of your set-up would help.....

Can't solve your SharpCap issue.... Have you tried the camera in FireCapture - just to verify and check the drivers? (I use my ASI 1600 under Firecapture)

I use the ASI 1600 for solar imaging..... I just stick with the Unity gain (139) (In FireCapture) and gamma 50. The exposure set to give a good histogram +/- 80 % Seems to work for me. Ken

I have two set-ups.... My HEQ5 for solar is located on the balcony and connected to the indoor laptop using 5 Mtr extensions - the power (at 15V), the Synscan controller, the focus motor, the tuning motor and the camera. Works well. I also have a NEQ6 pro in the observatory, connected back via a local laptop and Cat 6 cable (Teamviewer) to the office. I use EQmod / ASCOM/ CdC to control the NEQ6 - this arrangement may work for you using an extended cable and powered USB hub. Don't know anything about WiFi connections - sorry.

Well done! Just shows what a good LS50 mod can achieve on a 160mm aperture system. Excellent result.

Fabio has just released his latest update to AstroArt V7. It just gets better and better. You can download a trial version.... http://www.msb-astroart.com/default.htm

I certainly fall into that category!!!! The Quark solar filters - the Chromosphere version has a slightly narrower bandwidth which allows better contrast and definition on surface features - sunspots, filaments, spiculae etc. The Prominence version has a much wider bandwidth which allows the Doppler shift in the proms to be included in the view, giving a more pleasing rendering of the various features - hedgerow, surges and sprays etc. Having said that many (I mean most) users go for the Chromosphere version to try to get the best of both worlds. An energy rejection filter (ERF) is an expensive filter which allows the Ha light to get through but basically blocks all the other light and heat energy. These can cost hundreds of dollars! https://www.baader-planetarium.com/en/baader-d-erf-energy-rejection-filter-(75---180mm).html Without an ERF on a scope like the Mak you run the risk of cooking it! Overheating the secondary etc etc etc. Don't do it! The Quark is basically designed to be used on a >f5 refractor. With smaller apertures <100mm you can get away with using a UV-IR filter close to the Quark as an ERF. Larger scopes need an up-front $$$$ ERF. For solar imaging a fast frame mono camera is the way to go. I use an ASI 174MM and an ASI 1600MM with FireCapture software for my imaging. ( I use a double stacked SM60 on my ED80 with a BF15 blocking filter)

Louise, The good news is light pollution doesn't existing in spectroscopy!! Valerie does her work from the centre of Paris (!!) Christian works from his balcony near Toulouse..... We can remove the unwanted sky glow signal - sodium, mercury lights etc. very easily during processing. LED lights.....well that is more difficult. Ken

Louise, I should also have added that spectral exposures can be very long - to build up the signal and improve the SNR. I use 20 x 240s min subs (!) hence the benefit of a cooled mono camera. I don't know if SharpCap can handle cooled cameras and long exposures.