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View Full Version here: : ZWO ASI 2600MC Pro UV/IR Cut window


Martin Pugh
16-09-2021, 10:57 PM
Hi there.

the subject camera has a UV/IR cut protect window in front of sensor, unlike most OSC cameras where you need to add such a filter in the optical train somewhere.

I am using this camera with a lens and trying to determine whether that protect window is actually good enough and have 'doubled up' on the UV/IR cut need by placing such a filter on the lens.

Anyone with any similar experience or views on this?
thanks
Martin

JA
17-09-2021, 06:22 AM
Hi Martin,
You could always try to find some filter transmission curves for the ZWO UV/IR filter and perhaps compare them with those of the other filter you are using. If the other filter you use is from one of the major brands, or if you have a friend with a handy spectroscope have it measured.

Other than that you could always try to judge the effectiveness oF the ZWO UV/IR by imaging with and without it and check for any bloated stars, and then do the same with ONLY the other filter fitted.

Best
JA

JA
17-09-2021, 06:49 AM
I found a transmission curve for the ZWO 1.25inch UV/IR filter which in all likelihood is identical to yours. Try to compare it with similar data from your other filter.....
https://astronomy-imaging-camera.com/wp-content/uploads/IR-Window-graph1.jpg

Edit...
Surprisingly to me the Badder uv/ir filter, by way of example, shows significantly higher transmission in the visible band ~98% compared with my eyeballed average of around 93% for the ZWO uv/ir filter. If one can rely on manufacturer's data to discern such a difference that is. There's no substitute in testing your own.
https://www.baader-planetarium.com/en/baader-uvir-cut--l-filter.html
Best
JA

Martin Pugh
17-09-2021, 11:34 PM
Thanks JA, that’s good info. I should be able to find the info on the other filter for comparison.
Cheers
Martin

Startrek
18-09-2021, 12:23 PM
Martin,
I’m still trying to get a definitive answer on whether the 60D-2 IR cut protective window which is described in the 2600MC specifications is fact UV/ IR cut
I’ve sent a post on the ZWO forum a few days ago and received only one reply from a member who obviously doesn’t have this camera as they just looked up the specs in ZWO. They attached a link to the ZWO site under filters which shows the D60 UV IR cut filter suitable for the 2600MC and a few other cameras
This is a 60mm diameter x 2mm thick filter accessory for the camera which I assume is screwed into the image train somewhere or in a filter wheel ? It certainly doesn’t fit inside the camera nor on the outside as the outside screws dust cap is M42
See attached photos of my 2600MC pulled apart showing main body of camera with sensor and main cover protective window which is rectangular

The protective window on the 2600MC may very well be UV IR cut , but have not seen any written evidence from ZWO to say it is ( maybe someone has but I haven’t come across it )

One observation is the description on the camera specs say D60-2 IR cut and the filter accessory says D60 UV IR Cut , obviously different

Hopefully ZWO will see my post and reply soon ..... but I won’t hold my breath

Cheers
Martin

JA
18-09-2021, 02:41 PM
Hi Martin,

Although somewhat ambiguous, I found reference to it on page 10-11 of the ZWO ASI2600 manual which covers the MM and MC versions that I annotated in the image below. It would be good if ZWO titled their own graphs, but a little deduction can be used. See.....
280985

Interestingly it looks identical, transmission response wise, to their 1.25inch UV/IR filter that I posted the transmission curve for in an earlier post. So you're good to go guys ...... start clicking away :thumbsup:

Best
JA

Startrek
18-09-2021, 04:16 PM
Thanks JA
Shouldn’t have to delve deep into documentation and graphs , charts and what not etc... to make a learn’ed deduction about something so simple
They should spend more time on correct detailed documentation of their specifications and products to eliminate doubt.
Thanks again
Cheers
Martin

Martin Pugh
18-09-2021, 08:10 PM
Thanks guys.

JA
19-09-2021, 10:11 AM
Martin, Martin ..... :D Sounds like a line from a Chevy Chase movie - Doctor, Doctor :D:D:D

To be ABSOLUTELY certain that there is in fact a UV/IR filter fitted one could test the filter out of the camera or even in the camera using an infrared light source. I was racking my brain earlier, but forgot about the humble infrared remote control trick I've used to test basic remote control function. Most IR TV remotes use something like a 800-900 nm -ish wavelength emitted by the IR diode. Most cameras and even mobile phone cameras can see this wavelength to an extent and it often paradoxically shows up as violet in colour. This is a simple way to test if a remote control is functioning with your mobile phone. Extend this trick to your filter to find out if it is indeed a UV/IR filter or clear glass or use your 2600MC to observe this IR light source and you can conclude whether a UV/IR filter is fitted, given that the camera has an extended IR response.

Here is a video I made on my mobile phone to demonstrate this test for my own and hopefully the interest of others....
https://www.youtube.com/watch?v=REXmjop00kI


Best
JA

xelasnave
19-09-2021, 11:44 AM
JA you are just too clever...that is brilliant:thumbsup:
Alex

The_bluester
19-09-2021, 12:37 PM
ZWO only mention "IR cut" for their stand alone filter, but when you look at the transmission curve it is obviously a UV-IR cut, it might as well be sold as a lum filter. I would expect that the window on the 2600MC would be the same. I have never seen any oddball reflections with the 2600MC that I used to get from the 294MC, which only had an AR coated window, they were resolved by putting the "IR cut" filter in the train.

JA
19-09-2021, 01:32 PM
Thx Alex :thumbsup:..... Anything for a bit of a fun challenge

Best
JA

Hemi
08-10-2021, 08:01 PM
Hah! I very much concur!

Martin Pugh
18-10-2021, 01:20 AM
Thanks JA.