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Need help choosing EAA camera!

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#1 DeepSkyDiver

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Posted 20 July 2021 - 02:46 PM

Hi all, brand new to cloudy nights and EAA in general. Really need some help choosing a camera. I am using a Celestron c6 on the SE mount, and controlling it all through CPWI/sharpcap 4.0. I bought a ZWO ASI385mc and apertura(GSO) .5x focal reducer two weeks ago without doing a great deal of research based on seeing it recommended all over the place for EAA. Upon receiving it I tried it for 3 nights in a row and really struggled with the small-ish field of view. It was taking me hours to find even one object. Absolutely frustrated I contacted high point scientific who I bought it from, told them I wanted the larger asi294mc and asked to return the 385. They sent me an RMA number and shipping label to send it back.  The night before I sent it back I took a step back, calmed down and really tried to solve the problems I was having. I replaced the cheap wobbly red dot finder on my c6 with a sturdy telrad and Instead of using a low power eyepiece to align I used the camera and the crosshairs overlay in sharpcap. I used a 4 total stars spread across the sky and my go-to accuracy was amazing all night. Everything I slewed to was nearly dead center in the ASI385mc. I had a great night of EAA. But Alas, I had to send it back the next day since high point was expecting it.  
 

So here’s my dilemma, purchase another 385mc, or go with something else entirely? My main interest is galaxies, and planetary nebulae, and color isn’t a huge deal for me. (The 385 didn’t really show color  or a ton of detail in distant galaxies anyway). I’m just looking for the absolute most sensitive and highest res camera for getting the most out of galaxies and nebulae. I’ve seen some people using the asi178/183MM but I am worried the small pixels will take longer to build an acceptable image(field rotation in the se mount shows after 5-10 minutes) I am also worried if I go with the 294mc that small objects will be difficult, which is mostly what I want to observe. 

So, any camera recommendations? Budget is around $700-800 top end.  I want to stay in the ZWO range. 
 

thanks all and I am looking forward to all the good info on cloudy nights! 


Edited by DeepSkyDiver, 20 July 2021 - 02:53 PM.


#2 GazingOli

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Posted 20 July 2021 - 02:57 PM

Hi,

 

I started out with an ASI224 with CPC800 @ f/6.3, which is a very sensitive camera but a small FOV and I know exactly what you mean when struggling to find the objects. Hower I even managed to run the camera at f/10, which is probably the smallest FOV you can get.

 

Now I got an ASI294 MC, which I bought second hand. Gives me a big FOV and a lot of fun. For galaxies I am also using an ASI178 with great results.

 

One of the best choices might be the ASI533 MC pro, but I do not like the price and also not need the cooling, which also requires additional wiring etc.

 

So go on with the ASI294! It is nebulae time and you will enjoy the colours. Some examples are here: https://www.cloudyni...021/?p=11221014

 

Later you could think of a b&w camera which is even more sensitive and great for galaxies like that:

 

M51 C8f6Asi178_50frames_400s_cropresized.jpg

 

CS.Oli


Edited by GazingOli, 20 July 2021 - 03:01 PM.

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#3 Sky King

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Posted 20 July 2021 - 03:05 PM

Welcome to Cloudy Nights! smile.gif bow.gif waytogo.gif  Here's a good video to watch. Gary's more recent ones are good too. I didn't hear "plate solving" in your post. It's free (ASTAP) and works better with a big FOV like a DSLR (in case you have one of those, use it!).  Get started and upgrade later once you get some experience with your gear and stars. The ASI533MC is a popular EAA choice and comes with spacers and adapters to connect it.


Edited by Sky King, 20 July 2021 - 04:30 PM.


#4 Cey42

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Posted 20 July 2021 - 03:28 PM

I started very similarly to you a year ago. I had a C6 with F6.3 reducer using ZWO 178MC. I got very frustrated with the small FOV. I too was interested in planetary nebulae and with galaxies secondary. I upgraded to the ZWO 294MC and I have been very happy with it ever since. The color is great for planetary nebulae. With the 385 your FOV is .55x.31 degrees and going with the 294 it will increase to1.47x1.00 degrees. The larger FOV will make it a lot easier to find your DSOs. I recommend the 294MC.

 

 

Here is an image of M57 with the C6 @ F6.3 with the 294MC with a total exposure of 88 seconds. This is after doing EAA for only 2 months.

M57-2020-10-24-11x88s-_WithDisplayStretch.jpg

 

 

Since you are already using SharpCap, definitely spend time learning the Polar Alignment tool and Plate Solving. These two features will make your life so much easier.

 

 

Then when you have extra money, I agree with GazingOli, buy a mono camera for galaxies. It makes a huge improvement. I went with the 294MM and it has been great for galaxies.

 

 

Have fun.


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#5 DeepSkyDiver

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Posted 20 July 2021 - 03:31 PM

Thank you for the info oli. I have been checking out the ASI533mc pro as well. it is nice new generation camera and is on sale for $100 off right now. I am just not sure how to connect it to my c6. it has the standard celestron 1.25" visual back on it. the asi385mc made it easy, it came with the 1.25" nose that just screwed to the cam and I simply slid it and and adjusted focus. I have no idea how the pro series cameras work in regards to attaching them to a 1.25" receptacle and getting the proper back focus. I am not even sure if it will clear the base on my SE mount towards zenith. 

 

Can you use the ASI294 for smaller galaxies as well or just large objects? I have a large interest in many of the obscure and smaller NGC galaxies/planetary nebula. I would rather a camera that works excellent on smaller objects than compromise and get one with a large FOV for the 4-5 larger deep space objects that cant fit into the view of smaller sensors(m42, m8, M33, M101, etc). I am sure you can just crop the photo, but will it still have good quality and not be pixelated?



#6 GazingOli

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Posted 20 July 2021 - 03:38 PM

I did not compare the ASI294 and ASI178 at galaxies so far. If you are sure you will not miss the color, then the ASI178 MM could be an economic start for you. I got mine second hand for 250 EUR. You might want to check out my gallery with a lot of galaxies in spring this year with the ASI178, link in my signature. However be aware that the C8 has more aperture and thus a better resolution than the C6! Your field of view will be a little larger also.

 

For some time now I am using a wedge and hope to get even better results on galaxies in the future.

 

CS.Oli

 

edit: of course you can use the ASI294 also for smaller objects - see above M57 from Cey. Here is one from me, too, from last Sunday:

 

M57 C8f6.3ASI294UH _26frames_208s_crop.jpg

 

You can also use binning and ROI in SharpCap to improve the results on small objects


Edited by GazingOli, 20 July 2021 - 03:42 PM.

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#7 alphatripleplus

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Posted 20 July 2021 - 03:58 PM

If you want the most sensitive camera for faint galaxies, you will find that mono cameras will go deeper than colour cameras with the same sensor type, because of the Bayer matrix on colour cameras. So for example, the 294MM should see deeper than the 294MC, the 183MM should go deeper than the 183MC, etc.

 

Incidentally, I started EAA with an ASI224MC (similar in pixel sensitivity to the 385MC) which is one of the most sensitive colour cameras, although it has been around for a while. Subsquently I moved to a SX Lodestar X2 mono CCD and an ASI290MMM mini mono. Both the Lodestar X2M and ASI290MM mini are way more sensitive than the 224MC - but you don't get to see things in colour with them. 

 

So you might want to consider which is the more important to you -  sensitivity or colour.


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#8 DeepSkyDiver

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Posted 20 July 2021 - 04:11 PM

Wow oli, those galaxies in your gallery using the asi178 are breathtaking. exactly what kind of detail I am looking for! I understand mono sensors are more sensitive, but the 178/183 have small pixels. wouldn't that just make the sensitivity less? I Definitely want something more sensitive that will show more detail than the asi385mc. Color or no color truly does not matter for me. I am used to mono views from my 12" dob so it is natural to me. I am just looking for the best possible image. I was comparing your image of m101 with the asi224 and asi178 and it is very clear the 178 does a much better job.


Edited by DeepSkyDiver, 20 July 2021 - 04:16 PM.


#9 GazingOli

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Posted 20 July 2021 - 04:53 PM

when I was in your position to choose my first camera I did a lot of calculations about sampling - so I never thought the ASI178 would work well with the C8. But then I got one and gave it a try and it turned out that, at least for EAA the ASI178 MM does a great job despite the FL of the scope and the small pixels of the camera.

 

The ASI294 seems to be a bit smoother, however. B&W cameras tend to be more sensitive without the Bayer mask and probably the ASI294 MM would work even better with the C8, but the price...

 

CS.Oli



#10 barbarosa

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Posted 20 July 2021 - 05:26 PM

The uncooled 294 comes with a 1.25" nosepiece, Just screw it on and insert in the diagonal as you would an eyepiece. There should be no need to move it in and out to obtain focus. A SCT has a considerable focuser travel because of the moving primary.

 

If you want to put the camera on the rear port you should be able to just insert the nosepiece into the VB and still get focus. if not, if the camera needs to be farther out, buy the Celestron T2 adapter. It has SCT threads to go directly on the rear port. The other end has M42 threads that will into the 11mm ring on the front of the camera.

 

To check for clearance problems  push the OTA forward on the dovetail clamp, rotate the rear port down and measure the distance to the top of the mount base. The uncooled 294 is 62mm long. The T adapter is 49.6mm flange to flange. About 113mm total, allow something for the swing.

 

The 294 sensor is 11.7Mega Pixels 4144X2822. The 385 sensor is 2.12Mega Pixels 1936×1096. You have the option to use an ROI with the 294 and essentially duplicate the image scale of the 385.

 

Many perhaps most galaxies have little or no color, but there are very important exceptions that show blue and red areas. The primary reason to buy a mono camera is the increased sensitivity compared to a color camera. You could be the mono 294 and get a tremendous increase in pixel count and in sensitivity, but will you need it for EAA with an SE mount? The mount will be the limiting factor. It is just not suitable for long exposure work. I say that as a former owner of two SE mounts.

 

I was seriously considering selling my 294Pro, but a couple of moonlight sessions with the RASA8 and the NBZ filter persuaded me to postpone that. The first 20s image at gain 300 made the case. For EAA it was just better than the 183Pro, more sensitive and a larger field of view.

 

With DSO work in mind do consider a cooled camera, though it is not needed for planetary work there is a visible benefit with DSOs.


Edited by barbarosa, 20 July 2021 - 05:28 PM.

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#11 DeepSkyDiver

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Posted 20 July 2021 - 06:34 PM

Barbarossa, could you explain what ROI is? Is that just using the zoom feature on sharpcap? Totally new to all this camera stuff. If the 294 can be set to a smaller FOV for small objects it totally makes sense to just go with that camera since it can cover the whole size spectrum. I see now that the 294 has slightly larger pixels than the 385, does that make it more sensitive?


Edited by DeepSkyDiver, 20 July 2021 - 07:28 PM.


#12 barbarosa

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Posted 20 July 2021 - 09:33 PM

In SharpCap the control panel has the option to select parts of the sensor, regions of interest. For example you might select a region of 1920x1080 or 640x480 pixel as the image area, You can position that area anywhere on the sensor. SharpCap now works as if the sensor had been reduced to whatever size you select.

 

This is particularly useful in high frame rate lucky imaging  (capture many frames, throw out the worst, stack the rest). The frame rate generally increases as the image area decreases. This does not magically make a large format sensor as fast as a 290 or 224 but it moves it up by a useful amount.

 

As you know the size of a target relative to the image area in an eyepiece increases as the eyepiece focal length decreases. This is true of sensors also. When I put the 294 on the RASA the field of view is significantly larger than it is with the smaller 183 But by selecting a smaller ROI the image area can be equalized and I get the benefit of the more sensitive 294.

 

The 183 has more pixels than the 294 so it would seem to be a better candidate for zooming without visible pixelation and it is. However the 294 has the wider field of view, so 200% zoom gives a different result than 200% with the 183, However I can select an ROI for the 294 that is a close match for the 183 and then the result is similar.

 

All of these sensors are > than HD so one consideration is whether you will be viewing  them on an HD display or a 4K display or an 8k display. If your display, like my computer display, is 1080p then all of the data above that is lost anyway. If you display is like our big screen, 3840x2160 then you more of your high resolution image is viewable.

 

You can make a larger sensor work like a smaller one, but not the reverse.

 

But to repeat if your are primarily interested in planets, then you should pay great attention to the frame rate at various resolutions.

 

AstronomyTools has a nice field of view calculator that let's compare the relative size of targets with different scope and camera combinations.

 

Pixel size is related to sensitivity, larger pixels are going to be more sensitive than smaller pixels. Photons per unit time will be larger with larger pixels.

 

With an f/6.3 or f/10 scope on an alt az mount sensitivity is not a trivial concern. And in that respect I should have mentioned (software) binning. You can in SharpCap and other apps also bin your camera, that is you can combine in software 2 or more pixels into one If I select 2x binning then the effective pixel count on the camera drops by half and the size of each pixel doubles. The was great feature of CCD cameras, where it could be done in hardware, but it remains useful on CMOS cameras where it is done in software and not quite as effectively.



#13 DeepSkyDiver

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Posted 20 July 2021 - 10:11 PM

Thank you Barbarosa, that clears a ton of questions up I had actually. Looks like the asi294mc is the best option. Huge FOV, you can bin to get more sensitivity, has the ability to do smaller ROI for smaller objects, and its color(I know.. I said color didn't matter for me but it is nice to have) It makes sense that nearly everyone is using it I guess! I run sharpcap and cpwi on a basic HP laptop with a barely hd resolution screen(1366X768) outside while observing, and my desktop inside which I use to view the images after is only 1080p. So if I understand it correctly, the extra pixel count from the 178/183mm cameras wouldn't even show me more detail unless I view the images on a higher res monitor. Even the 385mc wasn't showing me all the detail possible due to my monitor. I would rather the wider FOV the 294 provides and I can do a ROI for smaller objects. Should have bought it from the beginning, but I was apprehensive about dropping $700 for something I have never tried. Now that I have had a taste of EAA with the asi385mc I know that it is for me and worth the investment! 


Edited by DeepSkyDiver, 20 July 2021 - 10:12 PM.


#14 alphatripleplus

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Posted 21 July 2021 - 07:07 AM

Just my 2 cents: The 294MC is not going to be as sensitive as a 294MM. To be honest, I doubt you will find an uncooled  294MC much different than a 224MC or 385MC except for the much larger field of view. The 294MC pixels at 4.63 microns are slightly larger than the 3.75micron pixels on the 224/385MC and the lowest read noise is slightly higher (worse) on the 294MC. The slightly larger pixels of the 294MC mean slightly lower resolution and slightly more sensitivity compared to the smaller pixels of the 224/385MC.

 

You will definitely have more real estate with the 294MC, and maybe fewer hot pixels (which can be calibrated out) but it isn't going to match a mono 294MM in terms of sensitivity.


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#15 DeepSkyDiver

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Posted 21 July 2021 - 08:28 AM

Alpha, I was doing a lot of thinking and plugging in different camera in telescope tools last night and I came to the same conclusion you just said. If my pc can only show up to 1366x768, the only thing the 294 is affording me is a larger FOV. Nearly everything I want to view fits in the frame perfectly of the ASI385mc/asi178mm. There are only a select couple of objects that do not fit(veil, m42, m33, and a few others). Not sure the $400 price jump is worth it for those couple objects... now, I am just deciding between the ASI385mc color with 3.75um pixels/1936X1096p, or the monochrome asi178MM with 2.4um pixels/3096/2080p. Both of those show higher resolution than my monitor can display, but I am not sure how to figure out which is more sensitive, the 385mc or the 178mm. 178mm is monochrome which is more sensitive, but the pixels are smaller. 385mc has larger pixels but is color. Kind of stuck now.

#16 barbarosa

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Posted 21 July 2021 - 09:44 AM

You have pretty much sorted out the advantages and disadvantages of several cameras for your current scope and preferred targets. You can put all the pros and cons in a chart. You can assign weights to each factor. You can search the web for images made with the scope and cameras on you list (tricky because of post processing). You can sleep on it. You can look up analysis paralysis.

 

The answer I see in your posts is a lower cost camera with about an HD pixel count and a sensor diagonal > than 1/3" but < 4/3 or APS C. Mono and not cooled. Second choice same criteria but a color cam.

 

My suggestion is get the color cam unless you are quite certain that you need the added speed of a mono cam or plan on doing narrow band imaging in an EAA style. But either way you are not stuck forever in mono or color. By the way I do have a mono cam. Right now it is on the  guide scope, but it gets used now and again for small DSOs. I don't do much narrow band work. There is no one best answer.

 

Save a few bucks, enjoy whatever camera you buy and  if and when things change sell it or keep it. There are always uses for a second camera while selling it can recoup a large portion of the purchase price. Toss a coin if you must but get to imaging.wink.gif


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#17 alphatripleplus

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Posted 21 July 2021 - 10:01 AM

Yeah, I can certainly understand getting caught in analysis paralysis. My own experience, for what it's worth, was to get the 290MM mini mono. Even though it has 2.9micron pixels compared to the Lodestar X2 mono CCD with its huge 8.4micron pixels (my first mono camera), the 290MM goes just as deep and shows more detail at the typical focal lengths that I use (generally under 800mm). 

 

I don't worry about monitor resolution when considering a camera, as I can always zoom in SharpCap or ASILIve to any scale I want on a monitor. However the pixel scale of your camera/scope set-up  (which depends on the camera pixel size and the scope's focal length) determines how much detail your camera can actually resolve, so pixel size is a consideration. For example, with my C8 reduced to a 750mm focal length, the 290MM's 2.9micron pixels have a pixel scale (or resolution) of 0.8 arcsecs/pixel which gives good sampling with my typical seeing. At that focal length, I won't see any more with smaller pixels. If you operate at even shorter focal lengths, a camera with small pixels will show details (due to its smaller pixel scale) that a larger pixel camera can't resolve.

 

I agree with Dave though - don't worry too much about the camera if it is not too expensive. Try one and change it if you decide it is not for you.


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#18 GazingOli

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Posted 21 July 2021 - 11:07 AM

one thing that might be important is finding the objects. a small FOV can be a curse when looking for dim objects. the ASI224 worked very well in regard to sensitivity and filled the screen but finding objects with 1280 mm FL drove me almost crazy sometimes. goto is hardly ever acurate enough to get the object into the center of the FOV and the bigger the FOV the better the chances that the object is visible at first sight. and even if you are using plate solving there is a minimum FOV required to make it work. just to consider...

 

CS.Oli


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#19 DSO_Viewer

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Posted 21 July 2021 - 11:12 AM

Just my 2 cents: The 294MC is not going to be as sensitive as a 294MM. To be honest, I doubt you will find an uncooled  294MC much different than a 224MC or 385MC except for the much larger field of view. The 294MC pixels at 4.63 microns are slightly larger than the 3.75micron pixels on the 224/385MC and the lowest read noise is slightly higher (worse) on the 294MC. The slightly larger pixels of the 294MC mean slightly lower resolution and slightly more sensitivity compared to the smaller pixels of the 224/385MC.

 

You will definitely have more real estate with the 294MC, and maybe fewer hot pixels (which can be calibrated out) but it isn't going to match a mono 294MM in terms of sensitivity.

The question is do you want to view/observe in near real-time in color or mono? This decision would then allow you to choose between the two very different cameras.

 

Steve 



#20 DeepSkyDiver

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Posted 21 July 2021 - 04:09 PM

Yes I tend to get quite caught up with overthinking and overanalyzing. Really makes the decision hard when there are so many options. I know what the asi385mc can do based on my 3-4 nights with it before returning it. I bit the bullet and just ordered the monochrome asi178mm. They are both on sale right now for $299 so it is not a huge investment like the 294MM to try it out. Astronomy tools sensor calculator says for my seeing conditions, and the c6 with .5x reducer that the smaller pixels of the 178 is actually better. I am about an hour/hour and a half south of Cherry springs PA. It is Bortle 2.5-4, depending on moon phase, but there are horrible LED streetlights shining right into my backyard that block a large portion of the sky. this makes it hard to get good images due to the background glow washing out the object. I have an optolong CLS, and UHC filter to try too. I have read monochrome cameras are a great candidate for using a narrow band H-alpha filter, which nearly negates any kind of light pollution.

In the beginning I struggled with the small FOV. Now that I figured out how to use the sharpcap crosshairs overlay for aligning instead of a low power eyepiece it has gotten much better. Using CPWI I can add as many alignment stars as I want to further add accuracy. Maybe I was just getting lucky all night, but all 12-15 objects I slewed to were all nearly dead center in the 385mc’s frame and only needed very slight clicks on rate 2-3 to be perfectly centered. I was able to go up to 15 second exposures with the Alt/az SE mount too. Although closer to Polaris I had to cut it down to 4-8 seconds max. Field rotation did start to obviously show after 6-10 minutes of stacking. Hopefully the mono camera can capture light a little faster so I don’t have run the stack as long. I know the wedge would help but I want to see if I can get the quality I want out of the normal Alt/az configuration first before spending another $350 on the wedge. I have no plans or interest in getting into full blown astrophotography, just don’t have the time, patience, or energy to do it. EAA is great for me. I got into it because my solid tube 12” Dob was slowly becoming a chore to use. I love it, but 100lbs of scope is quite a bit to lug out into the yard by myself. This 6se setup is under 30lbs ready to go.

Edited by DeepSkyDiver, 21 July 2021 - 04:13 PM.

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#21 alphatripleplus

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Posted 21 July 2021 - 04:49 PM

 I have read monochrome cameras are a great candidate for using a narrow band H-alpha filter, which nearly negates any kind of light pollution.

 

A H-alpha filter is only going to help on targets that emit significantly in H-alpha - typically emission nebulae, and for these it will work great under LP or a full moon.  I use one with my mono camera on emission nebulae. However, for targets that emit broadly across the spectrum (such as galaxies) a H-alpha filter will be of no use, unfortunately.


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#22 dcweaver

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Posted 23 July 2021 - 08:17 PM

Your experience is very similar to mine.  I had an early Nexstar alt-az mount with a 4" Mak and an ASI224.  It was difficult to get my bearings with the small sensor, but it really wasn't the camera.  It was about alignment fundamentals.  Like you, I settled down and worked out a good alignment procedure using a finder and the camera.  This, combined with the focal reducer and plate solving, fixed all my issues getting on target.  A lot of the time plate solving wasn't even needed.

   
Here's what I did.  You will find it was similar to what you discovered, and should inspire some confidence that any camera you pick will work well.  Personally, I would try an ASI290 Mono.  With the 0.5x reducer, it will frame all but the biggest galaxies, and it is relatively inexpensive.  It has produced excellent results for many on the forum. (moot point since you selected the 178... should work well!  The rest still may help)

   
- 8x50 right angle finder with crosshairs.  I can't see squat in my light pollution with a non-magnified finder.  The finder made a huge difference.  Polaris was now easy to see and center.  Do a rough alignment with the main tube using the Moon, and then do a bright star.  Polaris works well because it doesn't move around.  Getting the finder aligned to the main tube will put any star you center in the finder on a small sensor.  You can use the crosshairs in SharpCap to do the final alignment.

   
- Level the mount.  The alignment routines don't absolutely need this.  But I've found things work better with a level mount, especially the auto 2-star align which I highly recommend.

   
- Use Polaris as your first alignment star.  The Celestron sky models like Polaris as the first star.  Also, it's easy to line up because it doesn't move much.

 

- Finish with "up and right" motions of the main tube.  This takes backlash errors out of the alignment.  Very important.  Forgetting to do this has messed up my alignments than anything else.

   
- Use auto 2-star alignment and add more points later.  Leveling the mount makes auto 2-star a breeze.  The second star is always in the finder, and once centered in it's crosshairs, it's on the sensor.  You now have to race the sky to get it aligned, but you never have to worry about not being on the star you selected.

   
- Pick your second star in the Eastern sky.  You want one that is above the "soup".  Don't pick anything too low or too high.

   
- Use the second stars natural motion to put it in the crosshairs in SharpCap.  This means move the scope to a position that lets the star drift into the center of the crosshairs.  Press align a fraction of a second before it crosses center.  Remember, finish with "up and right" then let the star drift across the center.

 

- When you do a goto, give the mount time to settle on the target.  These Nexstar alt-az mounts take a long time to finally settle in.  I have to wait 60-120 seconds sometimes before the mount catches up with the intended targets.

   
- Stay away from zenith.  These mounts don't do well if something is straight overhead.  Look at something else until the object has moved from straight overhead.

   
- Get a plate solver incorporated into SharpCap.  I use Ansvr.  It's pretty robust but can take longer than some other routines.  Others like ASTAP.  I haven't had good luck with ASTAP, but don't let my bad luck discourage you from trying it.  I will continue to try with different equipment in the hope that it works better with those setups.  Too many people like it not to keep trying.

   
A bigger sensor is not a bad thing.  If you have the money to spend, the ASI183MM or ASI294MM would be great choices. (also moot).  I wouldn't worry too much about pixel size.  The read noise on these cameras is so low, it only takes 5-10 seconds to get well above the read noise even with small pixel cameras with a 0.5x or 0.63x reducer (which is what I would switch to with your C6).  The good news is, your experience has already shown you that you can work with the smaller sensors as long as you exercise some care during alignment.


Edited by dcweaver, 23 July 2021 - 08:45 PM.

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