7 replies to this topic

[PJ Anway]

Now that I have retired, I am looking to improve in my solar imaging. Over the years, I have taken many snapshots, but have not used a dedicated video camera.

Not interested in color (I have use Photoshop for that), so I am looking for a mono camera that would fit my setup.

Here is what I have:

Zeiss AS 63/840mm  fl/13.3

Coronado SM60 h-alpha filter

Coronado BF10 blocking filter

 

Thanks for any help.

 

[MalVeauX]

Hi PJ,

 

656nm (HA) critically samples on pixels at the following focal-ratios:

 

2.4um critically samples HA at F9

2.9um critically samples HA at F11

3.75um critically samples HA at F14

3.80um critically samples HA at F14

4.8um critically samples HA at F18

5.86um critically samples HA at F22

 

If you're using your 60mm SM60 on your 840mm telescope, it will produce a disc that is 8.4mm in size approximately, so it will fit within the 10mm of your blocking filter. You would need a sensor that is larger than 9mm basically to image a full disc with this in one shot (rather than producing mosaics). If you are using that 840mm focal length, then the effective focal ratio with your SM60 etalon is F14. This perfectly matches a 3.75~3.8um pixel camera. So you could target a few different cameras that have that pixel size and have a larger sensor (1" or larger essentially). This would be sensors like the 533MC (yes color, only because it's not available as mono) and the 1600MM (no need to get cooling, so get the older non-cool version). There are other 3.75~3.8um pixel cameras but they are smaller sensors, so they would not do a full disc.

 

Alternative, don't worry about critically sampling and just use the largest sensor you can get, like the IMX174, IMX183 (I don't recommend this one due grid artifact issues), etc, for cost. They're only a little cheaper than the 1600MM, but the 1600MM is the ideal camera for your system.

 

Very best,

Edited by MalVeauX, 01 December 2020 - 03:03 PM.

[PJ Anway]

Thank you very much! This sure helps in my search.

[PJ Anway]

Hi PJ,

 

656nm (HA) critically samples on pixels at the following focal-ratios:

 

2.4um critically samples HA at F9

2.9um critically samples HA at F11

3.75um critically samples HA at F14

3.80um critically samples HA at F14

4.8um critically samples HA at F18

5.86um critically samples HA at F22

 

If you're using your 60mm SM60 on your 840mm telescope, it will produce a disc that is 8.4mm in size approximately, so it will fit within the 10mm of your blocking filter. You would need a sensor that is larger than 9mm basically to image a full disc with this in one shot (rather than producing mosaics). If you are using that 840mm focal length, then the effective focal ratio with your SM60 etalon is F14. This perfectly matches a 3.75~3.8um pixel camera. So you could target a few different cameras that have that pixel size and have a larger sensor (1" or larger essentially). This would be sensors like the 533MC (yes color, only because it's not available as mono) and the 1600MM (no need to get cooling, so get the older non-cool version). There are other 3.75~3.8um pixel cameras but they are smaller sensors, so they would not do a full disc.

 

Alternative, don't worry about critically sampling and just use the largest sensor you can get, like the IMX174, IMX183 (I don't recommend this one due grid artifact issues), etc, for cost. They're only a little cheaper than the 1600MM, but the 1600MM is the ideal camera for your system.

 

Very best,

Marty,

 

I'm a novice when it comes to astro cameras, so please let me know if I am understanding this correctly or am I way off?

Let's just say I was going to start with a camera with 5.86um pixel size. I would then need a 1.5x barlow to get my focal length to where I need it, to get critical samples in h-alpha?

[MalVeauX]

Marty,

 

I'm a novice when it comes to astro cameras, so please let me know if I am understanding this correctly or am I way off?

Let's just say I was going to start with a camera with 5.86um pixel size. I would then need a 1.5x barlow to get my focal length to where I need it, to get critical samples in h-alpha?

Correctamundo!

 

Very best,

[PJ Anway]

Hi Marty,

 

Well, I searched everywhere for a ASI533 and no one has one.

So I went with an ASI385 for now. It works for my telescope/h-alpha setup at 3.75µm

I know with the smaller resolution chip I will not be able to image a full disk, but I'm sure I can stitch a mosaic with Photoshop.

This should get me feet wet anyway.

 

Thanks for your help

[BinoGuy]

PJ, LOVE your gif.  

 

Don't forget, the ASI385 is color so resolution is 1/4 what it will be with a mono chip.  Looking forward to your images.

 

 

Clear Skies, BG  {°¿°}

[PJ Anway]

Hi BG - fellow Michigander :^)

 

So little is available from the astro dealers these days, it was hard to find a camera (or anything else for that matter).

I figured I could start out with the ASI385 and get my feet wet and later (after COVID, when they restock) look for something else.