ASI094 and IR filter

[GuLinux]

Hi,

I finally decided on (yet another) upgrade for my astrophotography gear, and I bought an ASI094MC Pro.

The camera just arrived, and it surely looks like a great piece of equipment.

The only big problem so far, is that I misunderstood how filters should be connected to the camera. I bought a 2" IR/UV filter, and it does fit perfectly when you use the 2" nose adaptor (obviously), but I also planned to use this camera with Canon lenses, and of course there doesn't seem to be a way to screw the 2" filter into the Canon adapter.

I saw this that could potentially help: https://www.365astronomy.com/TS-M54-to-M48-2-Filter-Thread-Adapter-for-Filter-Wheels-TS-Adapter.html

Except I can't be 100% sure it does the job, and I might lose precious 1.5mm of optical path, and be unable to focus to infinity.

Any thoughts?

[vlaiv]

How do you connect your Canon lens to camera now?

Probably good solution would be following:

One of these:

https://www.teleskop-express.de/shop/product_info.php/info/p9361_Baader-UFC-Base--Filter-Chamber-.html

And one of these to host filter:

https://www.teleskop-express.de/shop/product_info.php/info/p9362_Baader-UFC-2--M48-Filter-Slider.html

For camera side connection use this one:

https://www.teleskop-express.de/shop/product_info.php/info/p9367_Baader-UFC-M54x0-75-Camera-Adapter--male.html

And for lens side, depending on what connector you have (and I suppose you have M48 to EOS adapter):

https://www.teleskop-express.de/shop/product_info.php/info/p9376_Baader-UFC-S70-M48-Telescope-Adapter--female.html

If you don't have lens adapter, here is one that will work with above setup:

https://www.teleskop-express.de/shop/product_info.php/info/p10146_TS-Optics-CCD-Adapter-for-Canon-EOS-lenses-to-M48---12-mm-length.html

You just need to calculate proper flange distance for your lens (44mm if Canon EOS Lens)

And add up everything to correct spacing, so it will be something like:

17.5mm from sensor to M54 thread + 2mm of M54 to chamber adapter + 13mm Chamber + 1mm for UFC S70 / M48 adapter + X M48 mm spacer + 12mm length of Canon M48/EOS

So total length without M48 spacer is :  45.5

Anyone have -1.5mm spacer?

We probably need thinner M48/EOS adapter, let's see if we can find one ...

No, no luck, everything is longer than 44mm

But you could use adapter you listed in front of camera lens, you just need suitable adapter from your Canon lens filter thread to M54. This has few drawbacks - maybe stopping down lens to 2" filter free aperture (depends on lens and its aperture, maybe you will not stop it down if it is already smaller than 48mm), and your filter will be exposed to elements.

Then again, no need to use adapters, you can use something like this:

https://www.wexphotovideo.com/hoya-77mm-uv-ir-cut-filter-1532793/?pcrid=280614687534&mkwid=GLDGyVY6_dc&gclid=EAIaIQobChMI1dKm8-3o3QIVwrUYCh30iAVXEAAYAiAAEgIpqPD_BwE

With appropriate filter thread size for your lens. This way you will save astronomical filter from elements and use on telescope and have dedicated UV/IR cut filter for camera lens.

 

 

[GuLinux]

Thanks!

I already have this: https://astronomy-imaging-camera.com/product/canon-eos-m54-adapter

which has the exact length required for focusing already.

It is composed by two parts though, and there are threads inside it, so in theory I could screw an adapter with the filter inside it, problem is I have no idea what the thread size is...

[GuLinux]

You're right though, maybe the fastest solution is to just use a full aperture filter. I'm a bit concerned the results won't be the same, quality wise (I think I read full aperture filter introduce more problems, and more importantly, it wouldn't be a filter designed for astrophotography, and might filter out h alpha, for instance)